Matsumin's Valve Caster, a 12AU7-based booster and light overdrive running at 9 volts. A very fun little circuit that has a minimal parts count and actually generates a good amount of boost and some overdrive.
It appears Matsumin's site has gone 404'd on us, but here is my redrawn schematic with a few cap substitutions.
(http://www.beavisaudio.com/Projects/ValveCaster/MatsuminValveCaster.gif)
You can even run this one of a 9 volt battery if you don't mind chewing through batteries :) Otherwise, and 9 volt adaptor will be fine.
I was particularly surprised as to the effectiveness of the simple tone control...
Enjoy!
<edit: also simple enough to build 90% of the circuit right on the back of a tube socket>
(http://www.beavisaudio.com/Projects/ValveCaster/MatsuminValveCaster_OnSocket.jpg)
Cool!!! Any soundclips? I have only one tube, and don't know what to built with it, so I ask for soundclips to know how it sounds.
Nice
Anymore pics of the whole circut?
Not that familiar with tubes....
but 12au7....can this be a 12ax7 in this case?
After a little more research, it seems that au and ax are correct pin for pin, and the ax has about 7x more gain than au. However, i dont know if it is possible to run the ax in this circuit due to 9vdc?
Also how will the sound be? If its more overdriven, that could be a good thing. I'm just looking to get into tubes a little
Quote from: dano12 on December 11, 2007, 07:51:24 PM
It appears Matsumin's site has gone 404'd on us, but here is my redrawn schematic with a few cap substitutions.
He moved his site recently to a new address http://www.matsumin.net/ (http://www.matsumin.net/)
Thanks for the schematic! Looks like fun :)
this is getting built this weekend! got all the bits sitting around. Nice bit of tube mojo to add to the pedal board I think :D
Nice work dano!
I was wondering, what needs to be changed say I want to run this at high voltage?
QuoteCool!!! Any soundclips? I have only one tube, and don't know what to built with it, so I ask for soundclips to know how it sounds.
No clips yet, but it sounds pretty nice. On the overdrive side it is a bit raspy, but I think that could be tamed with some filtering caps.
QuoteAnymore pics of the whole circut?
Will try and box it up tonight for pix!
Quotebut 12au7....can this be a 12ax7 in this case?
If I remember correctly, the relative gain of the 12A*7 tubes goes something like this:
12AU7 20
12AV7 40
12AY7 50
12AT7 60
12AX7 100
I built it wih the 12AU7/12U7 as specified on the schematic. I tried a 12AT7 and it was too much gain and sounded really bad. I also tried a couple of 12AX7s and it sounded even worse--pretty much unusable. I'm not really very knowledgeable about biasing tubes, but I suspect using an AT7 or AX7 will require resistor value changes.
QuoteAfter a little more research, it seems that au and ax are correct pin for pin, and the ax has about 7x more gain than au. However, i dont know if it is possible to run the ax in this circuit due to 9vdc?
From the little I know, you'll probably want to go up to 12vDC to use the AX7. Here's a diagram for using a 12AX7 as a clipper pair based on info from another thread here:
(http://www.beavisaudio.com/Projects/ValveCaster/TubesAsClippers.gif)
So 12 volt to heater 4 and heater 5 to ground might work.
QuoteHe moved his site recently to a new address http://www.matsumin.net/
Thanks very much for the link! I'll update my schemo tonight to add the new URL.
QuoteNice work dano! I was wondering, what needs to be changed say I want to run this at high voltage?
I think this design made the usual compromises to run at low voltage. If you are going to create a tube boost/overdrive and are using high voltage, that are lots of better designs out there.
Thanks to Matsumin for this fun circuit.
Could you post a vero layout?
Does the tube light up btw?
Quote from: kurtlives on December 12, 2007, 05:56:33 PM
Could you post a vero layout?
Does the tube light up btw?
The tube will have to light up or it wouldn't conduct....
You could do as the picture above and put most components on the tube socket, or even a nice little tag board layout. Its really such a simple build it might be a good learning excersize to try and make your own layout and then post it here and ask someone to check it over. Should only take a short time ;)
I may try this out. Does anyone have a spare 12au7 or socket?
Vero is left as the dreaded "exercise for the reader". Mainly because I suck at vero. But you can build it entirely on the tube socket, pots and jacks.
And yes, it does glow!
Quote from: Papa_lazerous on December 12, 2007, 08:03:21 PM
Quote from: kurtlives on December 12, 2007, 05:56:33 PM
Could you post a vero layout?
Does the tube light up btw?
The tube will have to light up or it wouldn't conduct....
You could do as the picture above and put most components on the tube socket, or even a nice little tag board layout. Its really such a simple build it might be a good learning excersize to try and make your own layout and then post it here and ask someone to check it over. Should only take a short time ;)
Alright thanks, that is probbly what I will do.
I am new to building frm schems.....Is this negative ground?
How do I wire the 3PDT? WHere is the input and output?
Quote from: dano12 on December 12, 2007, 08:53:35 PM
Vero is left as the dreaded "exercise for the reader". Mainly because I suck at vero. But you can build it entirely on the tube socket, pots and jacks.
And yes, it does glow!
Looks awesome, but have you tried running it on 12VDC? I'm sure you would get a lot nicer response out of it :)
I was just wondering the same thing...
Also, it seems like it could be a fantastic input stage in front of a 386 based practice amp or a speaker simulator. I'll try to get my hands on a 12AU7 and build one of those. Does it require an 8 pin socket? (sorry, completely clueless about tubes...)
Can anyone recommend a good supplier that will ship to Canada?
^tubesandmore.com
If I remember correctly, the relative gain of the 12A*7 tubes goes something like this:
12AU7 20
12AV7 40
12AY7 50
12AT7 60
12AX7 100
If I wanted to use something besides a 12AU7 would I need to do any mods?
Regarding the 386 amp, that's the route I'm taking with my wired tube socket thing. Trying to fit it in a small plastic case.
For the questions about using a tube other than the 12AU7, as said earlier, they are higher gain and won't work nicely unless you modify the circuit, I don't know how to do that part.
tubesandmore.com has the tube and sockets, it is the standard 9-pin tube socket you would use for guitar amp preamp sections.
Here is a rough *unverified* wiring diagram for anyone who wants to try it.
(http://www.beavisaudio.com/Projects/ValveCaster/MatsuminValveCasterWiring.gif)
There are a few other circuits like this...the MarshaValve is one which feeds a JFET, I believe. They're good ones to get started with tube work :o)
I think if you tried to modify the circuit for 12AX7 use, you might end up in a no-win situation....they're really supposed to run on 100+volts, and at 9v, that's just asking a lot! But it's worth a try if you have something sitting on the breadboard. There are also low-voltage tubes that would work nicely for a higher-gain setting.
Expect to blow thru batteries (use wall wart), the heaters draw a LOT of current!
after building 32154 different electra and bazz fuss variations, i think this may end up being the first new kind of project to tackle!
Dano thats a real clean layout you drew, what software you using and how long did you ahve to put into that?
Quote from: dano12 on December 13, 2007, 09:31:09 AM
Regarding the 386 amp, that's the route I'm taking with my wired tube socket thing. Trying to fit it in a small plastic case.
For the questions about using a tube other than the 12AU7, as said earlier, they are higher gain and won't work nicely unless you modify the circuit, I don't know how to do that part.
tubesandmore.com has the tube and sockets, it is the standard 9-pin tube socket you would use for guitar amp preamp sections.
Here is a rough *unverified* wiring diagram for anyone who wants to try it.
(http://www.beavisaudio.com/Projects/ValveCaster/MatsuminValveCasterWiring.gif)
Thanks for the layout. It does however make it look like R2 is connected to pin 5 which is not the case.
Also why is lug 3 on the volume pot jumpered to lug 3 of the tone?
Quote from: kurtlives on December 13, 2007, 05:04:30 PM
Thanks for the layout. It does however make it look like R2 is connected to pin 5 which is not the case.
Also why is lug 3 on the volume pot jumpered to lug 3 of the tone?
R2 IS connected to pin 5, since both (R2 and pin 5) are connected to V+. Lug 3 of tone pot in jumpered to lug3 of volume pot just because the author inverted the order of tone pot & cap, with no remarkable differences.
Quote from: Papa_lazerous on December 13, 2007, 02:57:21 PM
Dano thats a real clean layout you drew, what software you using and how long did you ahve to put into that?
Thanks dude. I use Microsoft Visio. That one took about 20 minutes.
Quote from: kurtlives on December 13, 2007, 05:04:30 PM
Thanks for the layout. It does however make it look like R2 is connected to pin 5 which is not the case.
Also why is lug 3 on the volume pot jumpered to lug 3 of the tone?
Some of the wires follow a rather tortuous route, but I'm pretty sure it is all correct at this point.
I've tried to share lugs as much as possible to reduce the number of wires needed.
Cool
I also just realized there is no bypass switch. So basically I need to know which wire is the effect INPUT and OUTPUT. Thanks...
I am not familiar with Visio at all ???
Quote from: GibsonGM on December 13, 2007, 09:47:24 AM
I think if you tried to modify the circuit for 12AX7 use, you might end up in a no-win situation....they're really supposed to run on 100+volts, and at 9v, that's just asking a lot!
Yeah... I think what you're going to run into is that the 12AX7's gain is high enough (in this topology) that, with only 9v to work with, it's automatically going to clip the bejeezus out of any but the tiniest of input signals. You could redo the topology to cut gain and use some negative feedback, but then you'd get a squeaky clean sound, which probably isn't anything anyone would want.
I wouldn't doubt that the low gain was exactly why the 12AU7 was chosen.
How does they look for a full layout?
(http://img292.imageshack.us/img292/1110/tubepedalpm0.jpg)
No one?
Quote from: mojo_hand on December 13, 2007, 06:39:15 PM
Quote from: GibsonGM on December 13, 2007, 09:47:24 AM
I think if you tried to modify the circuit for 12AX7 use, you might end up in a no-win situation....they're really supposed to run on 100+volts, and at 9v, that's just asking a lot!
Yeah... I think what you're going to run into is that the 12AX7's gain is high enough (in this topology) that, with only 9v to work with, it's automatically going to clip the bejeezus out of any but the tiniest of input signals. You could redo the topology to cut gain and use some negative feedback, but then you'd get a squeaky clean sound, which probably isn't anything anyone would want.
I wouldn't doubt that the low gain was exactly why the 12AU7 was chosen.
Apologize for the newbish question. I am looking to try a tube project down the road and don't want to have to have a separate power supply on my board from my current. I get either 9 or 18 volts. Can this be converted to run of 18 instead of the 12 suggested for a 12AX7? Thanks
It's not good to run tube heaters that high, you can go lower than recommended 6.3V per heater (like this one does, with 4.5V per heater) but anything higher than 7V will reduce tube life noticeably. What you can do is put a resistor in series with heaters and run it of 18V, you'll get higher plate voltage which is good and you'll be able to tune heater voltage to 12.6V.
Let's see, if you start with 18V, minus 12.6V = 5.4V. From ohm's law you'll need resistance of approx. 5.6V/0.15mA = 37ohm. Approx power dissipation is 0.8W. I'd take 2W resistor of closest value to 37ohm. Any clearer?
QuoteFrom ohm's law you'll need resistance of approx. 5.6V/0.15mA = 37ohm
Small typo!!! It is not 0.15mA, but either 0.15A or 150mA (which is the 12AX7/12AU7 heater current). All the others values are right!
Quote from: bancika on December 14, 2007, 01:50:07 PM
It's not good to run tube heaters that high, you can go lower than recommended 6.3V per heater (like this one does, with 4.5V per heater) but anything higher than 7V will reduce tube life noticeably. What you can do is put a resistor in series with heaters and run it of 18V, you'll get higher plate voltage which is good and you'll be able to tune heater voltage to 12.6V.
Let's see, if you start with 18V, minus 12.6V = 5.4V. From ohm's law you'll need resistance of approx. 5.6V/0.15mA = 37ohm. Approx power dissipation is 0.8W. I'd take 2W resistor of closest value to 37ohm. Any clearer?
So if I am reading this correctly, I can use the layout above, but add the proper resistor to lower the voltage down to approx 12.6volts and that should work? I have a couple 12Ax7's lying around which is why I am very interested in giving this a shot.
good point, it's A, not mA :)
As you can read above, 12AX7 are not good candidates for this. Your voltage thingy is ok, however.
I thought the problem with the 12AX7 was 9 volts was too low. If it was 12, that was okay. Did I mis-read. Again, new to building anything with a tube in it. If not, I will have to shop for a tube as well.
does the change from mA to A change the resistor value?
yeah, changes 1000 times :)
with 0.15mA you'd need 37K resistor instead of 36 ohms.
If you want to utilize 12ax7 try something like shaka tube or tube driver.
Quote from: kurtlives on December 13, 2007, 07:55:30 PM
How does they look for a full layout?
(http://img292.imageshack.us/img292/1110/tubepedalpm0.jpg)
Anyone?
I think some of you guys will like this link http://www.takamine.co.uk/preamps/cooltube.html
Quote from: gluedtogether on December 14, 2007, 05:25:09 PM
I thought the problem with the 12AX7 was 9 volts was too low. If it was 12, that was okay. Did I mis-read. Again, new to building anything with a tube in it. If not, I will have to shop for a tube as well.
It wasn't really a tube-specific problem, it's that the gain of a 12AX7 is about 5 times as high as that of a 12AU7. In the circuit shown, that would mean around 25 times more gain total. So you might get a good clean out of it if you breathed gently on the strings, but anything more than that would clip. I guess you could stick a pot in front of it, although that would raise the noise level. Or always keep your guitar's volume control between 0.00 and 0.01. But I suspect that you'd be happier in the long run if you spent the $8 and got a 12AU7. That's not a very steep a price by tube equipment standards. ;-)
Ahh. okay. slowly learning. the direction I was looking at took it from clean boost to tube distortion. sorry for taking the thread off in a different direction. Always in the process of learning. thanks for explanations on all of this.
Hmmmm
Just got an 12ax7 in today for a tube driver or maybe an amp, and decided to try this out just because i couldn't look at the tube any longer without doing SOMETHING with it. I was expecting horrible sounds to come out of this. Unfortunately, no sounds :( I get absolutely no noise, and the tube doesn't light up at all, and I know I have heard people talk of the tubes lighting up. Any thoughts? Are there any things that I may have done wrong as a first timer with tubes? (Such as the first time on an opamp when you dont connect 8 to v+ because it is ohmitted( ;D) from the schematic)
Thanks!
This thread was talking about lighting a 12AX7 tube...
http://www.diystompboxes.com/smfforum/index.php?topic=63582.msg501595#msg501595
According to the thread you need to power the heaters it up to 12V.
-tR
THANKS!!
i build this in a few minutes today and sound great... 8) more than expected for runnig at only 9 volts. :o
(http://img240.imageshack.us/img240/2711/valve9vdn9.th.jpg) (http://img240.imageshack.us/my.php?image=valve9vdn9.jpg)
Nice job!
Any sound clips?
i record this from my cell phone
http://www.youtube.com/watch?v=cdcORgmfPl4
the noise is my old amp not the pedal
ATENTION
The Tone Control works in wrong way, change the wiring on the layout.!!!
I've lurked here on and off for about a year and a half and I guess it's about time I asked a (possibly) stupid question.
Dano's (and Matsumin's) schematic reminds me a little of a Fuzz Face. So what I'd like to know is, would it be possible to make a sort of Fuzz Face using this tube instead of a pair of transistors? I searched the archives a little and found a couple of brief mentions of people wanting to use a tube (or two) in a Fuzz Face, but there weren't any details. (And sorry if this is a derail in Dano's thread.)
Quote from: SidSeizure on December 18, 2007, 11:37:34 AM
I've lurked here on and off for about a year and a half and I guess it's about time I asked a (possibly) stupid question.
Dano's (and Matsumin's) schematic reminds me a little of a Fuzz Face. So what I'd like to know is, would it be possible to make a sort of Fuzz Face using this tube instead of a pair of transistors? I searched the archives a little and found a couple of brief mentions of people wanting to use a tube (or two) in a Fuzz Face, but there weren't any details. (And sorry if this is a derail in Dano's thread.)
There are possibly a couple of things you could do to make this distort more, along the lines of a fuzz. The first would be to add a pair of diode clippers at the end, before the tone control. Don't know if that would work with a tube, but it would be easy to try.
Another possible thing is to make two of them. Duplicate each tube stage where one feeds into another, that's four gain stages.
I wish there were 36 hours in a day, so many things to tinker with, so little time :)
if you want more distortion then really its time to leave this circuit behind....Its not really meant for that its just a boost. Try the matchless hotbox thats a great build and not too hard I made one Banika who has made the layout software for us has a build report on his site. Worth a look
So many projects, so little time...
This looks very interesting. I always wondered if there was a tube design that would run on only 9v. Looks like this might be my first foray into the world of tubes (after I complete 3 other projects)!!! :)
Finally had time to try this circuit out today. Decent sound, not to bad. After checking out some tube data, the mini 6111 looked like a good candidate. Its a medium mu twin triode tube. Different pinout, so after changing a few things on the breadboard, popped the tube in the socket and fired it up.
Wow, this sounds really good without having to tweak anything. As Dano stated, it chews through batteries quickly. I then hooked it up to an adjustable power supply to try higher and lower voltages. Using a 6111 tube run at 7 VDC, I would go as far as to say, this thing sounds great! A fat tone, decent sustain, and a nice, gritty, break up when the gain is cranked. A super simple, great sounding, one tube project.
Thanks for posting this Dano.
Jered
Any samples?
Thanks for the info. I was going to order some tubes and wondered which ones would be best.
Quote from: Jered on December 26, 2007, 12:40:07 AM
Finally had time to try this circuit out today. Decent sound, not to bad. After checking out some tube data, the mini 6111 looked like a good candidate. Its a medium mu twin triode tube. Different pinout, so after changing a few things on the breadboard, popped the tube in the socket and fired it up.
Wow, this sounds really good without having to tweak anything. As Dano stated, it chews through batteries quickly. I then hooked it up to an adjustable power supply to try higher and lower voltages. Using a 6111 tube run at 7 VDC, I would go as far as to say, this thing sounds great! A fat tone, decent sustain, and a nice, gritty, break up when the gain is cranked. A super simple, great sounding, one tube project.
Thanks for posting this Dano.
Jered
For the 6111, did you have have to change anything other than the pinout? I'd like to try this....
No, I didn't change anything except the pinout and voltage. I thought it sounded best at 7 volts, but the difference between 7 and 9 volts was marginal. I didn't have time to really mess around with components so you might be able to bring out the best with some tweaks. It sounded great as is, two of these together might give you a gain monster of a circuit.
Please let me know if you find improvements for this, I still have it on the breadboard and plan on trying a few things when I have time.
Thanks, Jered
Dano, I forgot to add, I tried 6112 and 6021 tubes and the sounded horrible. That's all.
Jered
give those 6021 to me if they are horrible ;)
just kidding, I'm looking to get them for a while
I got some 6021A I might make this in a minute ;)
he said they are horrible, so you too should give me yours :)
Why would I go and do that Bane? I will breadboard it for soemthing to do and tweak it a little for kicks, I have 8 MOS 6021A's dated 6-1958 Muhaha they are for my nano clone ;)
bummer :)
I know where there are more for cheap money. PM me if you want to know more mate
you've got a PM :)
hehehe...I just meant they didn't sound good in this circuit as is. I'm sure with a little tweaking they can sound good too.
Jered
This looks interesting. Can you use the standard 1/4 watt resistors or do you need higher rated ones due to the amount of current this is drawing? Has anyone measured how much current it draws in total? Also, would chaining two or more produce an overdrive?
I have an old Babani book that has a valve compressor schematic using 2 12AX7s but it needs at least 100v. I wonder if it would work using 2 12AU7s and 12v.
1/4 watt resistors worked fine for me. This thing burns through batteries, use a power supply/wall wart if you have one.
Jered
Quote from: col on December 30, 2007, 11:22:46 AM
This looks interesting. Can you use the standard 1/4 watt resistors or do you need higher rated ones due to the amount of current this is drawing? Has anyone measured how much current it draws in total? Also, would chaining two or more produce an overdrive?
I have an old Babani book that has a valve compressor schematic using 2 12AX7s but it needs at least 100v. I wonder if it would work using 2 12AU7s and 12v.
Hmmmm did you say valve compressor, feel free to e-mail me a copy of the schem ;) PM for my e-mail address I will ofcourse be forever greatful
[quote author=col link=topic=63479.msg504405#msg504405 date=1199031766
I have an old Babani book that has a valve compressor schematic using 2 12AX7s but it needs at least 100v. I wonder if it would work using 2 12AU7s and 12v.
[/quote]
I doubt it, doesn't seem reasonable to me that 12au7 which has much less gain will work even close to 12ax7 under 10 or more times less voltage.
Quote from: Jered on December 26, 2007, 05:24:47 PM
No, I didn't change anything except the pinout and voltage. I thought it sounded best at 7 volts, but the difference between 7 and 9 volts was marginal. I didn't have time to really mess around with components so you might be able to bring out the best with some tweaks. It sounded great as is, two of these together might give you a gain monster of a circuit.
Please let me know if you find improvements for this, I still have it on the breadboard and plan on trying a few things when I have time.
Thanks, Jered
I did a bit of searching and found some 6111's for 7 dollars at tubesandmore.com.
Have a few on order now, I can't wait to start tweaking with this new tube.
(http://www.tubecollector.org/main/6111.jpg)
On a related note, I dug up the datasheet for the 6111, and as it was designed for missles and aircraft, the datasheet says "For Operation at Altitudes up to 60,000 Feet" . Never saw that spec before :)
6011 Datasheet found here for anyone who is interested: http://frank.pocnet.net/sheets/079/6/6111.pdf (http://frank.pocnet.net/sheets/079/6/6111.pdf)
<edit: also found a potentially great way to mount those flying lead wires: use an 8-pin DIP socket as seen here: http://www.geocities.com/koalavilla/images/audio/pencil_pre_10.jpg (http://www.geocities.com/koalavilla/images/audio/pencil_pre_10.jpg) >
Quote from: dano12 on January 02, 2008, 02:18:21 PM
<edit: also found a potentially great way to mount those flying lead wires: use an 8-pin DIP socket as seen here: http://www.geocities.com/koalavilla/images/audio/pencil_pre_10.jpg (http://www.geocities.com/koalavilla/images/audio/pencil_pre_10.jpg) >
cool ;)
Wow, those 6111's are TINY! I might have to try that after I've built the 12AU7 version (tubes should be here any day :icon_mrgreen: )
Has anyone tried a two tube version yet? If so, would you mind providing wiring advice? I would like to try it, but my simple mind comes up with stupid ideas like making two entire circuits, running them in series and using dual gang pots to control both at once. Yeah.. I'm a newb.
Quote from: andrew_k on January 02, 2008, 04:22:36 PM
Wow, those 6111's are TINY! I might have to try that after I've built the 12AU7 version (tubes should be here any day :icon_mrgreen: )
Has anyone tried a two tube version yet? If so, would you mind providing wiring advice? I would like to try it, but my simple mind comes up with stupid ideas like making two entire circuits, running them in series and using dual gang pots to control both at once. Yeah.. I'm a newb.
here's a rough, unverified splice of the schematic showing two tube stages:
(http://www.beavisaudio.com/Projects/ValveCaster/twincaster.gif)
The 6111's arrived today, smaller than I thought!
(http://www.beavisaudio.com/Projects/ValveCaster/6111.jpg)
So with the added gain stage there is more gain?
Do you have full layout?
im assuming r3 goes to 9v?
Zach
Quote from: Zben3129 on January 05, 2008, 05:15:23 PM
im assuming r3 goes to 9v?
Zach
Its a safe bet that R3 goes to +9V as the plate would get no DC otherwise as the connection to V1A is de-coupled with a cap (C3) so only AC gets through there.
Looking at it I'd probably loose the first gain control, also has anyone worked out the loads lines or where the bias is set on these? I know its only at 9volts but it would be interesting to see where they are operating within there range
Surely C3 needs to connect to pin number 2 on the 2nd 12AU7, doesn't it?
Quote from: Isaiah on January 06, 2008, 02:31:08 PM
Surely C3 needs to connect to pin number 2 on the 2nd 12AU7, doesn't it?
yep, looks like a drawing mistake.
I'm interested now, found some 6111s and gonna try to find some 6112s (I'm sure they can be made to sound good)
I think that someone needs to re-draw it as the C an R numbers are repeating where its been copies and pasted. I am not going to do it as I am not building it but someone with some time could ;)
Regarding the schemo....That's just a rough splice showing the OP where to start. I wouldn't build off that :)
I tried two 6111's in a row last night on the breadboard, it drew too much current for my puny little 9vDC wall wart so I can't comment yet on how two in a row sound. I would hazard a guess that it would be quite noisy and may sound farty unless the gain is adjusted for each stage.
With a single 6111 it sounds pretty good, but I think the heater voltage is going to need to be kept to under 6.3v to avoid burning out the 6111. The little buggers get HOT by the way.
Thanks for the diagram Dano :)
I decided to put a SHO-like booster in front of the tube boost, hopefully to attain a little bit of that "hot signal into tube pre-amp" sound -- I have the circuit perfed, but I'm still waiting on damn slow valve delivery before I can test it out and attempt to tune for the sound I'm after.
This experimentation is FUN :icon_mrgreen: ...though yesterday my girlfriend finally commented on the quickly growing pile of circuits in my home studio :-\
I've been following this thread for some days now. Very, very interesting. Thanks for sharing Dano! I'm just waiting for you guys to come up with a final multi-verified circuit here, and THEN I'll build one too. ;D My knowledge of tubes is too limited yet, but this looks like what might become a nice entry point into the valve-realm for many people.
Neat thread Dano, and a neat design.
I really think there could be a whole lot more submini tube designs around. I' have a couple ideas ready for testing around the old Raytheon CK series tubes. they are mostly pentodes, but you can find the odd triode too. I'm planning a small 65mW all tube amp using a 5672, and a 5678 60-ish volt B+. the only real problem with 'em is the unusually high plate load required. the 5672 needs something like 20k, but Fred Nachbaur's "baby bear" using a 533ax would need 80k to get its 1.8mW; but could realistically run off of battery power(only drawing around 32-ish mA).
have a look at these submini monsters for ideas:
http://www.dogstar.dantimax.dk/tubestuf/gallery4.htm
scroll down to the "baby bear" using those teeny tubes even smaller that the 6111's and 6021's
as well as:
http://amps.zugster.net/
the submini section is really good!
Here's the updated schematic, this one includes the pin numbers for the 6111 in addition to the 12AU7. I've built and verified both.
(http://www.beavisaudio.com/Projects/ValveCaster/ValvecasterSchematicRevB.gif)
This is really helping me to better understand tubes, so thanks for sharing the knowledge!
So can this circuit do clean (or near-clean) boost? And would it be possible to use both triodes in push-pull type configuration at such a low voltage?
I've been getting my micro-tube-effect education from the Vox Valvetronix and forum member Brett so far, for the most part. Thread here:
http://www.diystompboxes.com/smfforum/index.php?topic=64053.msg505674#msg505674
i have an idea
what if, you use a 12ax7 as the main tube, and a 6111 wired as output clipping diodes?
Quote from: dano12 on December 12, 2007, 09:22:41 AM
I'm not really very knowledgeable about biasing tubes, but I suspect using an AT7 or AX7 will require resistor value changes.
Just a few thoughts from someone who knows even less;
Would it not be possible to put in a trimpot in place of the plate resistor for each stage of the triode for biasing purposes ?
It would be interesting to be able to use the ax7, au7 and ay7 since they are relatively abundant. And maybe running the cicuit at 18 volts ? As far as I know the 12ax7 is supposed to have a plate voltage of 100, but I guess at least
something will happen even at as little as 18 volts ?
And another question; are these triodes self biasing in a circuit like this ?
Maybe it's time for a sub forum for high voltage stomp box building ? With the proper warnings and disclaimers posted in front I guess such a forum could become a valuable addition to this site and a great learning resource and symposium for further experimentation.
Here's a resource for those (like me) who need to learn some triode fundamentals:
http://www.angelfire.com/electronic/funwithtubes/Basics_04_Triodes.html
Quote from: Krinor on January 07, 2008, 05:54:09 AM
Maybe it's time for a sub forum for high voltage stomp box building ? With the proper warnings and disclaimers posted in front I guess such a forum could become a valuable addition to this site and a great learning resource and symposium for further experimentation.
not a bad idea, there is a forum dedicated to valve stuff www.ax84.com (http://www.ax84.com) springs to mind there are others though ;)
Hey John, yeah I've seen a few (the one you mentioned, and also the great 18watt.com site and others), but I kind of like it here. And we would also keep the main focus on stomp box related stuff instead of going into tube amps which I guess is a bit outside the scope of this site. Hey Aron, how about it ? "Building your own high voltage stomp box" ? ::) Sorry, I'm drifting off topic. Back to Dano and this great little booster.
Hi
I'm just guessing, but I notice that the 12AU7 has low internal resistance. Only 10 to 15K, compared with 60 to 80k in the 12AX7. Given the low gain of both devices at these voltages, the low internal losses of the 12AU7 might help this critter work. A buffer might be useful at the output (e.g. a JFET source follower).
Vox gets reasonable tones from a 12AX7 at 15V in their Valvetronix series, but they use even higher loads (330k). And, yes, they do have an option that uses both triodes in a push-pull arrangement.
great work :icon_smile:
Quote from: brett on January 07, 2008, 07:39:40 AM
Vox gets reasonable tones from a 12AX7 at 15V in their Valvetronix series, but they use even higher loads (330k). And, yes, they do have an option that uses both triodes in a push-pull arrangement.
Isn't that a 12AU7 in vox pedals?
My knowledge of tubes and how to use them basically consists of hooking them up according to various schematics and seeing if they work. I'm about 50/50 on the success rate. I've been doing a lot of reading, but 99% of it is still a mystery to me.
Here's a really interesting idea from a guy who used a 6111 for a headphone amp. It uses a 555 and a voltage regulator to get the correct heater voltage and B+: http://headwize.com/ubb/showpage.php?fnum=3&tid=5878 (http://headwize.com/ubb/showpage.php?fnum=3&tid=5878)
In the continuing saga of my 6111 submini tube fetish, I tweaked this some more. After some breadboarding and measuring, it was clear that the 9v source in the previous schematic, as it relates to using the 6111, doesn't work well:
- The heaters call for 6.3vDC. At 9 volts on the previous schematic, they aren't going to last too long
- 9v was simply not providing enough boosth. So I bumped the supply up to 12vDC
To get a nice stable 6.3v heater voltage, and to add a little bit more control, I put together a power supply based on the LM317 adjustable voltage regulator. In combination with a 1Kohm pot/trimmer, I can tweak the heaters to as close to 6.3v as I want. I also added R1/C1/C2 to add a bit of noise reduction to the power supply. Note that the LM317 is going to get really hot, so slap a heat sink on it. You can get the 317 at Radio Shack, it's that common. Adjust TR1 to get 6.3v at the 'heater' connection.
Here's the schemo:
(http://www.beavisaudio.com/Projects/ValveCaster/Subcaster.gif)
And a picture on the breadboard:
(http://www.beavisaudio.com/Projects/ValveCaster/SubCaster_bb.jpg)
The end result with this new tweaked design is that it offers a substantial increase in boost over the 9v in/heater design, and the overdrive sounds a lot nicer.
Wow, that looks very promising.
Now I just wonder if this booster can be put in a little amp cicuit like this:
(http://i47.photobucket.com/albums/f191/krinor/Rubywithtriode.jpg)
Is it this simple, or am I missing something ?
Quote from: Krinor on January 07, 2008, 06:21:58 PM
Wow, that looks very promising.
Now I just wonder if this booster can be put in a little amp cicuit like this:
(http://i47.photobucket.com/albums/f191/krinor/Rubywithtriode.jpg)
Is it this simple, or am I missing something ?
I've had stability issues trying exactly that type of schematic when the gain of the tube stage is at max and you max the gain on the 386. Starts to oscillate pretty bad. If you keep the gain lowered on the tube pre-amp, and adjust the 386 gain to taste, it should work. My breadboard tests with the 6111 and JRC386 were disappointing sound-wise.
Dano, what tube are you using in that Tube Cricket of yours ?
Quote from: Krinor on January 07, 2008, 07:14:03 PM
Dano, what tube are you using in that Tube Cricket of yours ?
That's a 12AU7.
Let me dig up the schemo.
<edit: here ya go!>
http://www.beavisaudio.com/Projects/TubeCricket/TubeCricket_Final_2008.gif (http://www.beavisaudio.com/Projects/TubeCricket/TubeCricket_Final_2008.gif)
Quote from: dano12 on January 07, 2008, 07:18:02 PM
That's a 12AU7.
I was asuming that. :icon_wink:
Quote from: dano12 on January 07, 2008, 07:18:02 PM
Let me dig up the schemo.
Please do!
I'm thinking about maybe building a bridged thing with a tube in front. I'm not after the overdrive at all. I'd rather like a clean amp with a fixed gain (R2k2).
Edit:
Thanks! You've made me a very happy man!
Quote from: dano12 on January 07, 2008, 07:18:02 PM
Quote from: Krinor on January 07, 2008, 07:14:03 PM
Dano, what tube are you using in that Tube Cricket of yours ?
That's a 12AU7.
Let me dig up the schemo.
<edit: here ya go!>
http://www.beavisaudio.com/Projects/TubeCricket/TubeCricket_Final_2008.gif (http://www.beavisaudio.com/Projects/TubeCricket/TubeCricket_Final_2008.gif)
When is the kit coming out? I have been waiting forver for it
is there any kind of socket for the 6111?
yeah, I saw one on eBay for 7$ a piece, those are very small 8 pin sockets. You can use 8 pin DIL IC socket for this too (see dano's post on the first page)
Here's mine:
(http://i47.photobucket.com/albums/f191/krinor/ValveCaster3.jpg)
I built it in one of those gorgeous boxes from Pedalenclosures.
This is the point-to-point version. Did anyone else build from that layout ? Well now it's verified by me at least.
What a great little circuit. Thanks for posting this Dano!
I can see many applications for this one. It would probably be a nice building block for more complicated projects.
It is a bit "dark" sounding, meaning it has a lot of bass content (at least with my SG). How could this be fixed ?
Did you use the "full" layout I posted?
How does it sound? Sound-clips?
No I put a simple on/off switch in it. I wanted to hear it before installing a true bypass switch.
It sounds very good. Being absolutely subjective and esoteric I can tell you that it adds warmth, character and a vintage vibe to your tone. This tells you nothing of course, but you probably get the picture anyhow. Build it yourself. You won't be dissapointed. With some frequenzy tweaking I hope to get some of the rather abundant bass content to behave a bit.
Quote from: Krinor on January 10, 2008, 07:28:00 PM
Here's mine:
(http://i47.photobucket.com/albums/f191/krinor/ValveCaster3.jpg)
I built it in one of those gorgeous boxes from Pedalenclosures.
This is the point-to-point version. Did anyone else build from that layout ? Well now it's verified by me at least.
What a great little circuit. Thanks for posting this Dano!
I can see many applications for this one. It would probably be a nice building block for more complicated projects.
It is a bit "dark" sounding, meaning it has a lot of bass content (at least with my SG). How could this be fixed ?
Wow, that is marvelous! What a nice look.
For lowering bass, you could try lowering the value of either the input cap, or the coupling cap between the two tube stages.
Again, really nice job!
hi.. i worked more...
this is my version... dual overdrive
:icon_twisted: :icon_twisted: :icon_twisted:
(http://img245.imageshack.us/img245/2676/dsc00003xo6.jpg) (http://imageshack.us)
(http://img245.imageshack.us/img245/5913/fingscreamerprocesoyr6.th.jpg) (http://img245.imageshack.us/my.php?image=fingscreamerprocesoyr6.jpg)
evolution!!!
(http://img406.imageshack.us/img406/1208/fugscreameruq2.th.jpg) (http://img406.imageshack.us/my.php?image=fugscreameruq2.jpg)
http://www.youtube.com/watch?v=AYtpB10U8FM (whit my cell phone)
Is that just two of the original ones together? Or is it something new?
Quote from: Krinor on January 10, 2008, 07:28:00 PM
Here's mine:
(http://i47.photobucket.com/albums/f191/krinor/ValveCaster3.jpg)
I built it in one of those gorgeous boxes from Pedalenclosures.
This is the point-to-point version. Did anyone else build from that layout ? Well now it's verified by me at least.
What a great little circuit. Thanks for posting this Dano!
I can see many applications for this one. It would probably be a nice building block for more complicated projects.
It is a bit "dark" sounding, meaning it has a lot of bass content (at least with my SG). How could this be fixed ?
Now all we need is a picture with that gorgeous tube lit in the dark!
What tube did you use and just how much does it light up? :)
Lot of bass content, seems usable for bass maybe?
All in all, very nice build, congrats ;)
Wow, both of those pedals look awesome, great work!
What did you use to cut a hole large enough for the tube in the enclosure?
Quote from: Timebutt on January 11, 2008, 01:23:46 AM
Now all we need is a picture with that gorgeous tube lit in the dark!
What tube did you use and just how much does it light up? :)
Lot of bass content, seems usable for bass maybe?
All in all, very nice build, congrats ;)
Thank you. I used a 12AU7.
12xx7's don't really light up much no matter what circuit they're in. But if you like to play in the dark, then you will be able to see a tiny little glow in there. But seriously, it's the sound of these things that matter. My best 6L6's (NOS RCA's) has black glass housings. Can't see anything in there no, but the sound! Simply amazing.
I haven't tried it with a bass yet. Will do. good idea. :icon_wink:
Quote from: andrew_k on January 11, 2008, 03:28:06 AM
Wow, both of those pedals look awesome, great work!
What did you use to cut a hole large enough for the tube in the enclosure?
I used a reamer to cut the hole. Reamers are excellent if you have a steady hand. You just bore a little pilot hole and then off you go. Just be sure to stop and check from time to time so that you don't go to far.
Nice build Niopren. Care to share your layout with us ?
Edit: I've done some tests running the circuit at 12V.
Disclaimer: These are my subjective opinions! :icon_wink:
12AU7: Brand, Tube Amp Doctor. Nice muddy overdrive and sparkling clean tones. Lots of bass content. Has some nice compression.
12AT7: Brand, Tube Amp Doctor. Very nice overdrive. More distorted. A bit more sparkle on clean tones. Less bass content.A little bit more "open" sound with some more midrange. This particular tube sound better than the AU7 in terms of the quality of the overdrive. Where the AU7 sounds like a perfect tube for a blues horn this particular AT7 seems like a better choice for guitar.
12AX7: Brand, Electro Harmonix. Low output. Less gain than the AT7. This tube has been used for about a year. Probably time to discard it.
Conclusion: For that warm and cozy fireside jam, I'd go for the 12AU7. This one drips of honey and makes me want to grab a beer and play harmonica! For everything else I'd use a 12AT7. But that's just me. :icon_lol:
Quote from: kurtlives on January 10, 2008, 10:33:50 PM
Is that just two of the original ones together? Or is it something new?
only two of the original ones together...
one for boost (distortion)
Quote from: niopren on January 11, 2008, 08:03:07 AM
Quote from: kurtlives on January 10, 2008, 10:33:50 PM
Is that just two of the original ones together? Or is it something new?
only two of the original ones together...
one for boost (distortion)
Do you have some AT7's around ?
Maybe you could run a test with that double version of yours?
I'd be happy to hear your opinions on the following setups: a) 2 AT7's, b) One AU7 and one AT7 and c) vice versa.
Quote from: Krinor on January 11, 2008, 06:44:28 AM
12AX7: Brand, Electro Harmonix. Low output. Less gain than the AT7. This tube has been used for about a year. Probably time to discard it.
preamp tubes usually live much longer than one year...
Quote from: Krinor on January 11, 2008, 08:20:00 AM
Do you have some AT7's around ?
Maybe you could run a test with that double version of yours?
I'd be happy to hear your opinions on the following setups: a) 2 AT7's, b) One AU7 and one AT7 and c) vice versa.
i test the 12at7 in my pedal, and sound take more distortion, but dont like the saturation.
i use 2 12au7, better works in my case
Quote from: bancika on January 11, 2008, 08:50:24 AM
Quote from: Krinor on January 11, 2008, 06:44:28 AM
12AX7: Brand, Electro Harmonix. Low output. Less gain than the AT7. This tube has been used for about a year. Probably time to discard it.
preamp tubes usually live much longer than one year...
My mistake. I have played it for one year. But it was not new when I got it. I have another one in my champ. I'll try that one this evening.
If you want longer battery life use 2 - 9 v in parallel.
More head room with 18v ? Try 2 - 9V in series using a center tap for the heater.
(http://www.aronnelson.com/gallery/d/18556-1/Batteries.GIF)
Quote from: RLBJR65 on January 11, 2008, 11:10:29 AM
If you want longer battery life use 2 - 9 v in parallel.
More head room with 18v ? Try 2 - 9V in series using a center tap for the heater.
(http://www.aronnelson.com/gallery/d/18556-1/Batteries.GIF)
but make sure you run heaters with one battery only, 18V on heaters is no good.
Or use a battery for heater power and an 18 Volt power supply for the rest ?
Dano: How about a high voltage version ?
in that case it would be better to use a 12V regulator for heaters and ditch the battery all together
Sweet! A tube pedal that won't kill a noob (me). Can't wait to start the build!
A question for niopren, did you duplicate the circuit to make the dual overdrive? That's what it looks like, I just want to make sure.
Quote from: Faber on January 11, 2008, 05:31:28 PM
Sweet! A tube pedal that won't kill a noob (me). Can't wait to start the build!
A question for niopren, did you duplicate the circuit to make the dual overdrive? That's what it looks like, I just want to make sure.
He probably used this one:
(http://www.beavisaudio.com/Projects/ValveCaster/twincaster.gif)
Quote from: dano12 on January 10, 2008, 08:48:15 PM
For lowering bass, you could try lowering the value of either the input cap, or the coupling cap between the two tube stages.
I tried changing the 0,47uF input cap to 0,22uF. This cut into to the midrange as well as the bass content and rendered the tone control pretty much useless. I've left it stock now and I've ended up liking it that way.
A footnote though; Wouldn't it be possible to bleed some bass to ground by putting a cap over two of the lugs of the volume control without loosing too much of the mids ?
Quote from: Faber on January 11, 2008, 05:31:28 PM
Sweet! A tube pedal that won't kill a noob (me). Can't wait to start the build!
A question for niopren, did you duplicate the circuit to make the dual overdrive? That's what it looks like, I just want to make sure.
yes, i build two identical circuit... and wiring the DPDT for one circuit only boost the first circuit.
If you go high voltage, might as well build an amp. http://www.harmonicappliances.com/powerman/design/pman_full_A.pdf The 6021's sound great at higher voltage. Haven't tried the 6111 or 6112 sub mini's at higher voltage.
Jered
Hi
with this kind of thought in mind -
Quotein that case it would be better to use a 12V regulator for heaters and ditch the battery all together
- I built this today :
(http://www.aronnelson.com/gallery/d/18565-1/Triode+triode.jpg)
That's a faily low parts count - hence the pcb was only 2 1/2 x 1 1/2,
including the B9a socket :icon_smile:
My wall-wart is the charger for my 14.4V rechargeable drill, which puts out about 19V. The 7812 was getting very hot, so I used 3 diodes (denoted Dx*) ahead of it to drop the voltage to about 17V. With 17V input and 12V output the 7812 wasn't burning me any more.
The results were a very quiet circuit (DC throughout and low gain probably help) and some promising initial results.
Here's some scope output (1V grids) for different tubes and input levels (sine waves):
12AU7, 200mV input
(http://www.aronnelson.com/gallery/d/18566-1/12au7_200mV_1Vunits_small.jpg)
12AU7, 500mV input
(http://www.aronnelson.com/gallery/d/18568-1/12au7_500mV_1Vunits_small.jpg)
12U7 (low voltage dual triode, built for car radios etc, pin for pin compatible with 12A*7s), 200mV input
(http://www.aronnelson.com/gallery/d/18570-1/12u7_200mV_1Vunits_small.jpg)
12AX7, 200mV input
(http://www.aronnelson.com/gallery/d/18572-1/12ax7_200mV_1Vunits_small.jpg)
As you can see, the 12AX7 doesn't have much gain and is already clipping with 200mV of input.
But the 12AU7 manages about 6V p-p of output (gain of 30) and seems to work very well. Clipping is at just about the right amount of input (200mV p-p is about a fresh plucked string and 500mV a chord). Both sides of the output started to clip at about 1V p-p input, and the output got fairly square at about 2V p-p. So I think it will break up well with someboost in front.
I'll post some MP3s tomorrow, and try some more variations - maybe a small resistor on the cathode and a larger plate resistor on the second triode ?
cheers
Quote from: bancika on January 11, 2008, 11:40:38 AM
Quote from: RLBJR65 on January 11, 2008, 11:10:29 AM
If you want longer battery life use 2 - 9 v in parallel.
More head room with 18v ? Try 2 - 9V in series using a center tap for the heater.
(http://www.aronnelson.com/gallery/d/18556-1/Batteries.GIF)
but make sure you run heaters with one battery only, 18V on heaters is no good.
Yes 18V on the heaters would be very bad! Guess I should have noted the 5 / 3 on the 18V pic is the heater connection as related to Dano schem.
It was just a suggestion to add a bit of room and still keep it a simple low voltage project as it was intended to be.
Quote from: Jered on January 11, 2008, 11:52:44 PM
If you go high voltage, might as well build an amp. http://www.harmonicappliances.com/powerman/design/pman_full_A.pdf The 6021's sound great at higher voltage. Haven't tried the 6111 or 6112 sub mini's at higher voltage.
Jered
Yep!
Nice work Brett!
I was going to recommend the 12U7. There are tons of used and NOS 12U7 around don't know of any manufacturers making new ones though.
Hi
here is a clip. Please excuse the playing (nerves).
First part is clean (some breakup due to overloading the sound card), then the same riff played through the Triode triode (with a little boost), then a few chords (Triode triode, no boost), then the riff again, same as before, just played "harder". It's a bit hard to pick up in the clip, but there's a reasonable amount of difference between the second and fourth parts, and the circuit responds quite a lot to playing style and "attack".
http://www.aronnelson.com/gallery/v/BinOfBrett/Triode+triode+clean+-+boost1+soft+-+boost2_less+-+boost+2+hard+.mp3.html (http://www.aronnelson.com/gallery/v/BinOfBrett/Triode+triode+clean+-+boost1+soft+-+boost2_less+-+boost+2+hard+.mp3.html)
With or without boost, I reckon this is a great little circuit. Although most of my amps have tube preamps and are dirty, I would still use this as an extra valve stage. It has a feel of its own. It's a bit like a low gain pre-amp (e.g. the low gain channel in my Marshall JTM60), but a bit different, too. Very crisp.
I think it would be an excellent front end for many solid state amps, offering pleasant compression and distortion.
Maybe to temper the highs, you could add some high frequency bypass caps in parallel with the plate resistors. About 47pF would be right for the 470k resistor, and 100pF for the 220k resistor. Also, the output is so high that a 5:1 voltage divider (e.g. 470k:100k) could be put ahead of the output pot.
cheers
Possible improvement, depending on context:
I note that the original schematic and layout specify that the triode at pins 1-3 be used for the voltage gain stage, and 6-8 for the follower.
This isn't usually the best way to do it with a 12A*7. With battery power or regulated DC going through the heaters, it doesn't matter which triode you use in which position, but if you're using AC or less-than-pristine DC, the triode at pins 6-8 will be quieter, due to the location of the heater pins on the tube. (You can find mention of this in the data sheets on many 12A*7 series tubes.)
Just thought I'd throw that out there, since this design seems to be giving rise to a lot of variations, and some of them might benefit from swapping the triodes.
So, put simple what you're saying is that it might be better to use pins 1-3 for the follower and pins 6-8 for the gain stage ?
Will there be a noticable aural difference in such a low voltage circuit ?
It definately matters for circuits with AC heating and high gain, such as the Real McTube.
Any of the all-DC designs are ok regardless of order.
By the way, the Triode triode has plenty of gain in both triodes, so it's two gain stages, not a gain stage and a follower.
cheers
Quote from: Krinor on January 13, 2008, 06:27:21 PM
So, put simple what you're saying is that it might be better to use pins 1-3 for the follower and pins 6-8 for the gain stage ?
Exactly.
Quote from: Krinor on January 13, 2008, 06:27:21 PM
Will there be a noticable aural difference in such a low voltage circuit ?
If you're using AC or rectified AC for the filaments (or a hummy DC wall wart), hum will be reduced by using 6-8. How audible it will be depends on the circumstances. If you used shielded and/or twisted pair cabling for both signal and heaters, and approximated star grounding, it should be quiet enough that you'll notice the difference. If you did a bad job wiring it, and you've got a noisy fuzz feeding it signal, I'm sure you'd never know one way or the other. It's not a big deal, and it's a total non-issue in any circuit using clean DC for the filaments, I just mentioned it because few circuit tricks require zero materials and have zero downside, but I like using those few that do exist.
Quote from: brett on January 13, 2008, 07:52:12 PM
By the way, the Triode triode has plenty of gain in both triodes, so it's two gain stages, not a gain stage and a follower.
D'oh! I mis-remembered the schematic. I hereby renounce my use of the word "follower" in my earlier post. Everything else still applies, however.
Quote from: mojo_hand on January 13, 2008, 08:17:48 PM
Quote from: Krinor on January 13, 2008, 06:27:21 PM
So, put simple what you're saying is that it might be better to use pins 1-3 for the follower and pins 6-8 for the gain stage ?
Exactly.
Quote from: Krinor on January 13, 2008, 06:27:21 PM
Will there be a noticable aural difference in such a low voltage circuit ?
If you're using AC or rectified AC for the filaments (or a hummy DC wall wart), hum will be reduced by using 6-8. How audible it will be depends on the circumstances. If you used shielded and/or twisted pair cabling for both signal and heaters, and approximated star grounding, it should be quiet enough that you'll notice the difference. If you did a bad job wiring it, and you've got a noisy fuzz feeding it signal, I'm sure you'd never know one way or the other. It's not a big deal, and it's a total non-issue in any circuit using clean DC for the filaments, I just mentioned it because few circuit tricks require zero materials and have zero downside, but I like using those few that do exist.
Thanks for sharing. My build seems quiet enough, but I'll try these tricks in the next one I make and see if it gets even better.
Great job Brett! The pictures you made with your scope show the 12au7 and 12u7 looking very similar. Any sound differences?
Quote from: RLBJR65 on January 12, 2008, 08:39:40 AMThere are tons of used and NOS 12U7 around don't know of any manufacturers making new ones though.
where? :)
Hi
QuoteThe pictures you made with your scope show the 12au7 and 12u7 looking very similar. Any sound differences?
The 12U7 is definately a softer, cleaner tone. Even when boosted fairly hard, the 12U7 was mild. The 12AU7 broke up much earlier and harsher.
It's probably a bad analogy, but I was thinking that the 12U7 had a lighter, overdrivish, Fendery feel, while the 12AU7 is a dirtier, more Marshally tone. (Old Marshall, like an 18 watter or JTM, not a JCM or high-gain Marshall)
cheers
Quote from: bancika on January 14, 2008, 12:17:57 PM
where? :)
I have a surpluss store near me that has a box of them. The problem is that I don't think they would go and look if you called etc.
If you want some let me know I can go in a couple of weeks. The last one I bought was $4.00.
I just Googled "12U7 tube" and found 2 places on the first page :icon_wink:
"The 12U7 is definately a softer, cleaner tone. Even when boosted fairly hard, the 12U7 was mild. The 12AU7 broke up much earlier and harsher. "
Awesome. Thanks for the info. I have some 12au7 tubes already and 6011's on the way to play with on these low voltage type designs. I will get some 12u7's also.
What a great looking circuit; I've been trying to get into a tube build for some time. Thanks for sharing circuit.
Dose anyone have any thoughts on the affect of eliminating the tone control? Would there be some additional gain obtained as a result?
Thanks for your thoughts,
Lonzo
I don't think it makes such a big difference. At full tilt there is a tiny bit more gain than when it is turned all the way down. This tone control works fine, but it's not that effective. Personally I leave mine at about 1 o'clock. If your point is that you want to save some space and leave out a pot, you might still want to shape your tone by making a preset treble bleed. For instance you could replace the pot with a 50k resistor (to put it in the middle position). Or put sockets in and experiment with different values until you find the tone you like.
Good luck. This circuit is very easy to make and a lot of fun too. Use a 12 volt wall wart!
I was thinking about this circuit and I came up with something for someone who built this for a second time, or someone who is WAY too ambitious (like me).
Okay, so I looked at the argument about 12V vs 9V and I was thinking about using a 12.6V transformer and a full wave rectifier TUBE. Now, this might be too bulky for such a small pedal, but it would kinda be more like a real tube amp... Maybe I'm just crazy... errrr... maybe I'm crazier than I thought I was!
Didn't I also see something about the tube heaters needing (or wanting) 12.6V???
Not to mention, 2 TUBES LIGHTING UP!!!
As per tube recto, there would be no need, except for look, as a tube recto and diode recto do the exact same thing in this particular situation.
For the 9v and 2 tube argument, I agree. With both heaters + circuit drawing power, this thing is a 9v battery eater. In my pedal, I power by a 12vac wallwart, then rectify internally with diodes.
Zach
Quote from: Faber on January 21, 2008, 09:42:58 PM
I was thinking about this circuit and I came up with something for someone who built this for a second time, or someone who is WAY too ambitious (like me).
Okay, so I looked at the argument about 12V vs 9V and I was thinking about using a 12.6V transformer and a full wave rectifier TUBE. Now, this might be too bulky for such a small pedal, but it would kinda be more like a real tube amp... Maybe I'm just crazy... errrr... maybe I'm crazier than I thought I was!
Didn't I also see something about the tube heaters needing (or wanting) 12.6V???
Not to mention, 2 TUBES LIGHTING UP!!!
A 12.6v transformer will not give you the voltage you want for the filaments, unless you skip rectification and just use the AC. If you hook the heaters up in series, anything from 9v to 13v will work, although 9 is pretty low to do the job, and anything over about twelve and a half will reduce tube life. Something like 11-12 is probably ideal. If you're hooking up the filaments in parallel, halve those voltages. A 12.6v transformer produces 12.6 VAC, after that goes through a bridge rectifier and hits filter caps, what you end up with is 12.6 * 1.414 volts, less the drop across the rectifier diodes. In practice, this works out to maybe 16.5-17v, which is high enough to fry the heaters very quickly. If you use a different rectifier topology, you end up with 12.6 * 0.707 volts (minus losses), which might get you 8 volts, with luck. Tube diodes have higher internal impedance than silicon, so the voltage drop would be greater, but I really don't think by enough to drop your 16.5-17v to 12.6 or less.
If you want to do use tube-rectified DC for the heaters, you need a transformer in the 7-9v range (or half that if hooking them up in parallel). Or higher voltage and a regulated power supply. Do remember to get a bigger transformer, since you'll need to provide the rectifier with heater current, too.
Bear in mind that tube rectification's main mojo (power supply sag) does not apply to Class A circuits, which this one is, so the only benefit you're likely to get for the added expense and bother, will be cosmetic. If you want to make it more like a tube amp, there are probably better ways of doing that. You could, for example, use something like a 20k:2k output transformer. This would cut the output at clipping from close to 9v to a more manageable 0.9v, lower the output impedance, and probably make it sound a bit more like the real deal. Since you're very ambitious, I'll leave figuring out how to do that as an academic exercise. It's not hard, and learning is good. :)
Yeah, I do know that except for the tube lighting up it would be useless...
I am not 100% on the rectifier calculations so that's useful information!!!
So if the heaters are running off of AC, then don't rectify the heater voltage that you need and rectify what you do need...
It's a ridiculous idea, I know...
I've built one of these...It's awsome!!! Very very warm. I put it infront of my effects chain...And I love it!!!
Would the heater filament not prefer ~6.3v for longest life?
Depends on wiring.
If you go straight off the 9vbattery, yes you are declining tube life no matter what. For best tube life you need 6.3v or 12.6v. 6 or 12 is close enough, b9 is obviously nowhere near either. You either want 6.3 volts across pins 4+5 and 9, or 12.6v between 4 and 5.
Zach
I don't think that lower heater voltage (like 9V for both heaters) would lower tube life. It would just sound different that it's supposed to.
"I don't think that lower heater voltage (like 9V for both heaters) would lower tube life. It would just sound different that it's supposed to."
Lower heater voltage is actually worse. From the Tone Lizard,
Look about halfway down the page of this link to see the chart:
http://www.tone-lizard.com/Marshall_Myths.htm
"I would like you to study the diagram below carefully. It is from the book Audio Cyclopedia, by Howard M. Tremaine. It deals with the prospect of running the filament voltage on any tube at other than 100% rated value. The illustration shows that tubes will fail prematurely if the filament voltage is either higher or lower. For maximum tube life, the voltage must be 'right'."
"From the chart above, you should be able to determine that if a tube has a usable life of approximately 6,000 hours with its filament operated at 100% of the rated voltage, the tube's life expectancy is reduced to 1,000 hours just by lowering the filament voltage by 10%. This translates to a 6.3VAC tube being run at approximately 5.67VAC, or the input voltage lowered from 120VAC to approximately 108VAC. Ask your local tube guru if they have read Audio Cyclopedia. However, even 'experts' can disagree on anything and everything. GE published data confirming tube life is decreased substantially by raising the filament voltage, although tube life can be increased by lowering the filament voltage very slightly. The performance of the tube was purported to be more 'even' over its useful life. However, it should be pointed out that the slightly lowered filament voltage GE 'recommends' proportioned to the plate voltage (via your VariacTM) won't make a difference to our ears. People who set their VariacTM to 100VAC are only asking to replace tubes every other month. The GE report also stated that the transconductance of the tube was reduced dramatically, and an audible deterioration in performance was noted when reduced filament voltages were employed. So why bother?"
There are a lot of different figures on tube life and heater voltage, in part because different tubes respond differently. Those with thoriated heaters, for example, do well when run at rated voltage for their first 200 hours, then dropped to 95% of full voltage until they approach end of life. http://www.cpii.com/docs/related/22/AB18.pdf Dropping to 90% of rated voltage after the initial 200 hours may increase filament life to the point that heater failure will be eliminated as a cause of (thoriated) tube failure. http://www.burle.com/cgi-bin/byteserver.pl/pdf/tp202.pdf Tubes with oxide-based heaters are different. Power tubes can have their life shortened by running at lower heater voltages, but others often benefit from slightly lower voltages: at 10% above rated voltage, life will be cut by half, at 5%-10% below rated voltage, tube life will be significantly enhanced at the cost of slightly worse performance in various other regards. http://www.pmillett.com/Books/Tomer_1960_Getting_the_Most_Out_of_Vacuum_Tubes.pdf I suspect that the author cited by the earlier poster was thinking of power tubes when he condemned running tubes at reduced heater voltages, since it is very true with those.
My recommendation would be to never run power tubes at anything but their rated voltage, and to rectify, filter, and regulate that voltage if you're using expensive tubes. For other types of tubes, if high longevity matters more to you than squeezing every last bit of performance out of it, rectification and filtering are also good, but the target voltage should be 5%-10% below rated value. Anything lower than 90% of rated value will cause worse performance without enhancing tube life, and may actually shorten life. Using tube coolers and/or cooling fans will also increase life, often doubling it.
Using 9v in place of 12.6 for heaters is not a great idea from any perspective, in this schematic it has to be considered a matter of convenience rather than good design.
If you're playing in Timbuktu, carry a spare tenbuck Tube.
Why do backflips in order to avoid using a 12V DC wall wart ?
Quote from: brett on January 24, 2008, 08:50:47 PM
Why do backflips in order to avoid using a 12V DC wall wart ?
I agree, 12v would be a lot better, no idea why the original design didn't use that (can't read Japanese).
Quote from: mojo_hand on January 24, 2008, 09:36:36 PM
Quote from: brett on January 24, 2008, 08:50:47 PM
Why do backflips in order to avoid using a 12V DC wall wart ?
I agree, 12v would be a lot better, no idea why the original design didn't use that (can't read Japanese).
I'll see if I can do some samples of this circuit at 9v vs. 12v tonight, so long as I can get ProTools 7.4 and OSX 10.4.11 to play friendly. :icon_evil:
<noob> Perhaps as well as being better for the valve it also will provide a cleaner boost? </noob>
Sounds good, hope you get it working!
I'd say maybe more clean headroom. I can't really hear any discernable difference between 9v and 12v, but my wallet sees the difference between 9v bat and 12v ww. Trust me, go wallwart guys.
Just my $.02 (or if you use 9v batteries, $10/week)
Zach
Going back and reading Matsumin's notes, he mentioned that there are lots of schematics and designs for 12v, so he wasn't interested in making another 12v version.
His original goal was to make a simple tube booster that anyone could easily build and if possible, make it 9v, and this was the result. He doesn't know lots of the theory and concepts involved with using vacuum tubes in these type of circuits and that this was an experiment to see if he could just make it work.
He said that on breadboard, he got a more cleaner sound with higher voltages like 12v and 15v and that for people seeking more clean headroom to try higher voltage power supplies.
He got some nice sounds with the 12AT7 tube, but preferred the 12AU7 in this circuit. He tried a 12AX7 but said that it didn't work well at all with this design.
He mentioned that he designed this for single coil pickups and that his humbucker equipped guitars were too boomy.
Hope this helps.
Masa
Quote from: MasaRGR on January 25, 2008, 03:52:07 AM
He mentioned that he designed this for single coil pickups and that his humbucker equipped guitars were too boomy.
Hope this helps.
Masa
Now that makes sense. Maybe it sounds okay with single coils at 9v, but needs 12v to sound good with humbuckers ? I have only used mine with a rather dark sounding SG and a 12v supply. Sounds nice to me.
Thanks for the translations. Could I be so bold as to ask you to please translate the whole article and post it for the benefit of the DIY community ? I know a lot of people would be very gratefull. :icon_wink:
Quote from: MasaRGR on January 25, 2008, 03:52:07 AM
He mentioned that he designed this for single coil pickups and that his humbucker equipped guitars were too boomy.
Interesting. To me, it has more of a light OD jangle when I set the 'buckers on my carvin to split (single coil), but the sound when being driven by the full humbucker is still good; a lot more crunch to my ears and I prefer it over the single coil sound. It does do wonders for funk rhythms on my strat though, so long as I keep the gain low :o
Regarding 12V operation -- does anyone else notice a defined hum when switching to 12v? I know it's not the power supply as I'm using a BBE supacharger and just flicking the 9v/12v DIP switch for that output. My gut feeling is that it's a bias issue... and my n00b guess is that R3 (100k between pin 6 and V+) is responsible for bias?
I dig the sound of this circuit, but I'll wait until someone confirms or denies my guesses regarding 12v hum and bias before replacing the resistor with a pot.
Quote from: andrew_k on January 25, 2008, 04:34:40 AM
Quote from: MasaRGR on January 25, 2008, 03:52:07 AM
He mentioned that he designed this for single coil pickups and that his humbucker equipped guitars were too boomy.
Regarding 12V operation -- does anyone else notice a defined hum when switching to 12v? I know it's not the power supply as I'm using a BBE supacharger and just flicking the 9v/12v DIP switch for that output. My gut feeling is that it's a bias issue... and my n00b guess is that R3 (100k between pin 6 and V+) is responsible for bias?
I'm using a regulated ac/dc adaptor capable of 500mA. It's switchable between 9 and 12 v. I tried it with everything maxed on the valve caster and the amp turned up loud. There is a subtle hiss at these extreme settings. Switching between 9 and 12 volts does not alter that rather faint hiss in my case. All in all I was actualy surprised at how quiet this circuit was.
Quote from: andrew_k on January 25, 2008, 04:34:40 AM
Regarding 12V operation -- does anyone else notice a defined hum when switching to 12v? I know it's not the power supply as I'm using a BBE supacharger and just flicking the 9v/12v DIP switch for that output. My gut feeling is that it's a bias issue... and my n00b guess is that R3 (100k between pin 6 and V+) is responsible for bias?
I dig the sound of this circuit, but I'll wait until someone confirms or denies my guesses regarding 12v hum and bias before replacing the resistor with a pot.
Now you have rewired the heaters for 12V operation, right? If you're running them in parallel (6,3V operation) at 12V, that can't be good.
Jake
Quote from: Krinor on January 25, 2008, 04:12:00 AM
Thanks for the translations. Could I be so bold as to ask you to please translate the whole article and post it for the benefit of the DIY community ? I know a lot of people would be very gratefull. :icon_wink:
You're very welcome.
As for translating the rest, most of it isn't of much use as he makes lots of references to some obscure Japanese magazines and texts, and the rest is just some "shoulda/woulda" kind of brainstorming.
A few things that may be of interest - he said that he bought a tube socket with pcb pins - but the pins weren't sized for his board holes so he had to do a lot of bending and twisting to get the socket mounted. One thought he had was to just use a regular tube socket and attach the components directly to the base of the socket (ala DanO) or use a small turret board or lag board. He used some vintage ceramic caps in C1 and C4 as well as an oil capacitor for some extra "mojo". He did say that his layout wasn't too well thought out as he would have to remove knobs and unscrew the pots to get access to the tube ;D
He did give big props to Bancika's DIY layout creator and mentioned how much he appreciated the upgraded version.
Built mine! Will only work with 12V though (I'm using a 12AT7, may or may not have anything to do with it). Sounds very very good. just for jollys, turn the vol and gain up full and crank out the riff to Smoke on the water!
I tried an AX7 that I had lying around and that sounds different still, not too bad, quite useable in fact but just not as clean as the other.
Quote from: Krinor on January 25, 2008, 05:23:16 AM
I'm using a regulated ac/dc adaptor capable of 500mA. It's switchable between 9 and 12 v. I tried it with everything maxed on the valve caster and the amp turned up loud. There is a subtle hiss at these extreme settings. Switching between 9 and 12 volts does not alter that rather faint hiss in my case. All in all I was actualy surprised at how quiet this circuit was.
Damn. Exactly the same power situation as me, but yours doesn't make the odd noise.
Quote from: Jake
Now you have rewired the heaters for 12V operation, right? If you're running them in parallel (6,3V operation) at 12V, that can't be good.
If I had half a clue what that means, I'd respond appropriately... ??? :icon_eek: ???
Quote from: MasaRGR on January 25, 2008, 06:28:25 AM
Quote from: Krinor on January 25, 2008, 04:12:00 AM
Thanks for the translations. Could I be so bold as to ask you to please translate the whole article and post it for the benefit of the DIY community ? I know a lot of people would be very gratefull. :icon_wink:
You're very welcome.
As for translating the rest, most of it isn't of much use as he makes lots of references to some obscure Japanese magazines and texts, and the rest is just some "shoulda/woulda" kind of brainstorming.
A few things that may be of interest - he said that he bought a tube socket with pcb pins - but the pins weren't sized for his board holes so he had to do a lot of bending and twisting to get the socket mounted. One thought he had was to just use a regular tube socket and attach the components directly to the base of the socket (ala DanO) or use a small turret board or lag board. He used some vintage ceramic caps in C1 and C4 as well as an oil capacitor for some extra "mojo". He did say that his layout wasn't too well thought out as he would have to remove knobs and unscrew the pots to get access to the tube ;D
He did give big props to Bancika's DIY layout creator and mentioned how much he appreciated the upgraded version.
There are so much incredible information on hi-fi and other such things in Japanese. I think I need to learn some of that language eventually! Right now I can only look at photos and sometimes I'm lucky enough to accidetally stumble across something that turns out to be a link to a schematic. Ha,ha. Please share more goodies with us if you come across something that might be of interest here. :icon_wink:
Quote from: andrew_k on January 25, 2008, 06:58:29 AM
Quote from: Krinor on January 25, 2008, 05:23:16 AM
I'm using a regulated ac/dc adaptor capable of 500mA. It's switchable between 9 and 12 v. I tried it with everything maxed on the valve caster and the amp turned up loud. There is a subtle hiss at these extreme settings. Switching between 9 and 12 volts does not alter that rather faint hiss in my case. All in all I was actualy surprised at how quiet this circuit was.
Damn. Exactly the same power situation as me, but yours doesn't make the odd noise.
Quote from: Jake
Now you have rewired the heaters for 12V operation, right? If you're running them in parallel (6,3V operation) at 12V, that can't be good.
If I had half a clue what that means, I'd respond appropriately... ??? :icon_eek: ???
If he was running the heaters in parallel he would be sending 12 volts to pins 4 and 5 and use pin 9 for ground, right ? In this case pin 5 gets 12 volts and pin 4 goes to ground. Pin 9 is not used.
Are you suggesting that there should be a separate 6.3 volt heater circuit on this one ?
If properly understanding the above, the 12.6 V could be connected without any changes, according to the wiring of this image?
[/quote]
(http://www.beavisaudio.com/Projects/ValveCaster/MatsuminValveCasterWiring.gif)
[/quote]
Quote from: niopren on January 10, 2008, 10:06:02 PM
this is my version... dual overdrive
(http://img245.imageshack.us/img245/2676/dsc00003xo6.jpg) (http://imageshack.us)
Niopren, or Dano, is it possible to have a layout for the dual valve schematic?! I'd like to have one as this one above for one valve only...Thank you...
Hi
RE: dual tubes
My "Triode triode" circuit, which is similar, gave plenty of gain and distortion with just 1 12AU7 tube. (soundclip posted above)
If you want monster gain, just use a booster in front.
RE: series and parallel heater wiring
For those new to the 12**7 series and similar tubes, the element connects 4 and 9 and 9 and 5.
Serial connection runs from 4 thru 9 to 5, with 4 at 12.6V and 5 grounded. ( Or 5 at 12.6 V and 4 grounded).
Parralel runs from 4 to 9 AND 5 to 9, with 4 and 5 at 6.3 V, and 9 grounded.
For a circuit such as this I recommend using DC for the filaments. Even better if it's a DC wall, wart, so that AC never gets near the circuit at all. This is because those hum-inducing AC currents in heaters are so large (hundreds of mA) relative to the signal (thousandths of a mA) that hum will appear if your wiring setup is less than perfect.
cheers
Has anyone tried clipping diodes yet? I already use a tube amp and I am mainly looking for a tube distortion type of pedal.
Quote from: Renegadrian on January 25, 2008, 08:58:41 AM
Quote from: niopren on January 10, 2008, 10:06:02 PM
this is my version... dual overdrive
(http://img245.imageshack.us/img245/2676/dsc00003xo6.jpg) (http://imageshack.us)
Niopren, or Dano, is it possible to have a layout for the dual valve schematic?! I'd like to have one as this one above for one valve only...Thank you...
The schematic for the dual version is posted on page 4 of this thread.
EDIT: Er... sorry. I didn't read that question properly. You probablu know where the schmo is.
Quote from: brett on January 25, 2008, 09:04:37 AM
Hi
RE: dual tubes
My "Triode triode" circuit, which is similar, gave plenty of gain and distortion with just 1 12AU7 tube. (soundclip posted above)
If you want monster gain, just use a booster in front.
RE: series and parallel heater wiring
For those new to the 12**7 series and similar tubes, the element connects 4 and 9 and 9 and 5.
Serial connection runs from 4 thru 9 to 5, with 4 at 12.6V and 5 grounded. ( Or 5 at 12.6 V and 4 grounded).
Parralel runs from 4 to 9 AND 5 to 9, with 4 and 5 at 6.3 V, and 9 grounded.
For a circuit such as this I recommend using DC for the filaments. Even better if it's a DC wall, wart, so that AC never gets near the circuit at all. This is because those hum-inducing AC currents in heaters are so large (hundreds of mA) relative to the signal (thousandths of a mA) that hum will appear if your wiring setup is less than perfect.
cheers
Thanks Brett! This thread is becoming a nice little tubenoob primer :icon_wink:
Yes, Krinor, I'd like to have a LAYOUT based on the schem we have some ages ago... ;)
EDIT: ooops, I meant "Pages"...This darn sylicon keyboard... :-\
Quote from: ItZaLLgOOd on January 25, 2008, 09:11:14 AM
Has anyone tried clipping diodes yet? I already use a tube amp and I am mainly looking for a tube distortion type of pedal.
Can't say that I've ever used clipping diodes in a tube circuit. Aside from extreme fuzz effects like the early germanium stuff, I think of diodes as a way to get around the fact that bipolar transistors often sound like crap when driven to clipping. With the lovely sound of clipping tubes, I'm not sure why you'd want diodes, unless you were wanting to play a lot of "Satisfaction" or "In-A-Gadda-Da-Vida."
I was curious about clipping diodes and tubes. I was under the impression that this project didn't clip a whole lot. I was looking for something with more distortion but "In-A-Gadda" was not the direction I wanted to head.
Well, with a reported gain of around 30, and output that's somewhere between 8 and 11 volts (depending on whether you're doing it with 9 volts or 12), the most you'd need to drive it into clipping would be 11v/30 = 0.37 volts. If that isn't enough gain for your pickups to drive it into clipping, more gain could easily be added -- switching from a 12AU7 to a 12AT7 might work, or you could just stick a single JFET in front of it and pick up additional gain of 4-5, boosting total gain to 120-150.
(Some people might cringe at the idea of "polluting" a tube effect with a solid state device, but I think that JFETs are just about perfect for this particular use.)
What about tube diode clipping? I have a few old 6AL5 tubes (twin diodes) lying around, but I don't know much about tubes in general. You could do the same thing with tube diodes as you normally do with solid state, but I don't know how useful it would be. Some things to consider:
-Would tube diodes clip like we are talking about here, or would the clipping voltage level be way too high?
-For the 6AL5, the spec sheet says it drops 10 volts per plate... My guess is that would be way too much in a low-voltage effect such as this, but I just thought I'd throw it out there as food for thought.
A regular diode to ground clipper will work just fine in this circuit. See Marshall JCM900 schematic. Diode and tube distortion in the preamp. Whether that sounds better than just adding more gain at the front, I don't know.
As for tube diode, maybe try it with a AMZ saturation control.
Hi
RE clipping.
As I said above, with a tad of boost I got this much clipping.
(http://www.aronnelson.com/gallery/d/18568-1/12au7_500mV_1Vunits_small.jpg)
With lots of boost (to 2V p-p), the output was squarish. It sounded similar to my JTM60 Marshall when fully cranked on the "vintage" channel. (a tone that's loved my many) Clipping diodes will be much coarser in tone, whether in this circuit or one such as the Distortion +, placed before it.
As said above, a single JFET booster will do the job of overloading this circuit:
QuoteWell, with a reported gain of around 30, and output that's somewhere between 8 and 11 volts (depending on whether you're doing it with 9 volts or 12), the most you'd need to drive it into clipping would be 11v/30 = 0.37 volts. If that isn't enough gain for your pickups to drive it into clipping, more gain could easily be added -- switching from a 12AU7 to a 12AT7 might work, or you could just stick a single JFET in front of it and pick up additional gain of 4-5, boosting total gain to 120-150.
cheers
or you could just stick a single JFET in front of it and pick up additional gain of 4-5, boosting total gain to 120-150.
Often we do, Jfet 'up front' is oft preferred, not that CMoS or..
For just getting the signal level up to a point where the next stage or so can start distorting it, some fine Jfet dirt, or Mosfet clean, or...other non-tube active circuit as gain stage certainly makes sense, i
If the first tube stage is only boosting and not distorting, well, that type of clean or even a touch of fine dirt leaves the subsequent tube stages to be used for producing the actual distorting properties we're looking for.
Not to say "Don't let any non-tube light distortion introduced by non-tube active in" before tube gets it's chance to distort.
@9vdc with 12a_7 tube providing boost and distortion, and not much headroom to work with, letting something else to much of the grunt work [many small signal device types bias @9v and sound great]...more tube distortion will be available as well as more output available which could be used for voicing options.
You could use another tube for that, but with battery, I'd stick to one tube.
There's probably a sweet spot for input level on the tube, adding preboost at least seems a logical way to find out if it's not preferred.
First priority for new tube here is to get the right power supplied and see if they light up, a little off isn't bad, and as long as they light up the tube should work, I've run them like that, but between the data sheets and other data, the right voltage for the heaters is always recommended.
Anybody tried 12AV7 in this circuit? I'm going to try it tomorrow and will post my results.
Guys, if you have a power supply you can use for this, do it. Using batteries, they barely last long enough to do any tweaking. The circuit goes from sounding decent, to degrading quickly, trying to work on tone improvements with batteries for power, in this circuit, is tough.
Jered
12AV6
IIRC - This tube was built to be driven (I believe in computer systems?)
Has roughly same gain as ax7
Would act the same as ax7 in this circuit if the above is correct
But why not try it, and tell us your results
Zach
Quote from: petemoore on January 26, 2008, 09:40:41 PM
For just getting the signal level up to a point where the next stage or so can start distorting it, some fine Jfet dirt, or Mosfet clean, or...other non-tube active circuit as gain stage certainly makes sense, i
If the first tube stage is only boosting and not distorting, well, that type of clean or even a touch of fine dirt leaves the subsequent tube stages to be used for producing the actual distorting properties we're looking for.
Thanks for elaborating, those were exactly my thoughts.
Were you talking to me Zach, about the 12AV6? I'll try it out. I'll have to go get the AV6's from the tube cabinet at the studio, I'll be down there Monday. The AV7's are right in front of me, going to run those first.
Jered
Sorry, meant av7,
Fingers mind and eyes don't always line up after exam week :icon_biggrin:
Zach
On the subject of tubes, here's a link to some tubes that have just been collecting dust.
http://www.diystompboxes.com/smfforum/index.php?topic=64670.0
Take a look, maybe there's some you guys might want.
Jered
OK, I had a chance to try out a few more tubes in this circuit. I tried 12AV7, 12AY7, 12AD7, 12BZ7, and 6072. None of which sounded any good. 6111 sub mini's are still my fave. Need to get some 12U7's to try.
Jered
Quote from: Jered on January 30, 2008, 03:51:14 AM
OK, I had a chance to try out a few more tubes in this circuit. I tried 12AV7, 12AY7, 12AD7, 12BZ7, and 6072. None of which sounded any good. 6111 sub mini's are still my fave. Need to get some 12U7's to try.
Jered
Did you try those with no other adjustments to the circuit? Coming from a transistor background, I would think that different tubes would need to be re-biased to sound right. Or perhaps this doesn't apply with this particular circuit ???
Quote from: earthtonesaudio on January 30, 2008, 05:09:03 PM
Quote from: Jered on January 30, 2008, 03:51:14 AM
OK, I had a chance to try out a few more tubes in this circuit. I tried 12AV7, 12AY7, 12AD7, 12BZ7, and 6072. None of which sounded any good. 6111 sub mini's are still my fave. Need to get some 12U7's to try.
Jered
Did you try those with no other adjustments to the circuit? Coming from a transistor background, I would think that different tubes would need to be re-biased to sound right. Or perhaps this doesn't apply with this particular circuit ???
The same is true of tubes, but the brute force approach is quick and easy. I'd wager that this circuit, with some adjustments, would sound lovely with a 12AV7 and a 50 volt power supply, but then it would be a very different project.
Hi
I think that valves with low Ri (internal resistance), and maybe low mu (the sound cows make) will work best.
The 12AU7 is the lowest of the common dual diodes (Ri about 7k, from memory), with the AT7 also fairly low (Ri about 12k ?). Note the Ri figure is for normal operating voltages (e.g. supply at 150V) and the real internal resistance may be much higher under the conditions in these low voltage circuits.
I'm guessing that low internal resistance in the circuit (ie. at low voltage), as indicated by low Ri (on the datasheet), is the key to getting more electrons to flow at these extra-low voltages.
cheers
For those that have built this circuit, how well does the gain pot work? It's in a location that controls bias and feedback as well as gain so I was wondering how it "cleans up" well rolled back. Does it get gatey or weird at all? It seems a better place for it would be in between the gain stages like a regular tube pre amp.
Thanks.
Quote from: Caferacernoc on February 01, 2008, 11:15:13 AM
For those that have built this circuit, how well does the gain pot work? It's in a location that controls bias and feedback as well as gain so I was wondering how it "cleans up" well rolled back. Does it get gatey or weird at all? It seems a better place for it would be in between the gain stages like a regular tube pre amp.
Thanks.
The gain pot works very well in my build (using a 12AT7), at min gain I have to drop the guitars vol pot a little to get totally clean boost but the again I have fairly hot humbuckers. Not gatey or weird at all, very smooth control.
Quote from: Caferacernoc on February 01, 2008, 11:15:13 AM
For those that have built this circuit, how well does the gain pot work? It's in a location that controls bias and feedback as well as gain so I was wondering how it "cleans up" well rolled back. Does it get gatey or weird at all? It seems a better place for it would be in between the gain stages like a regular tube pre amp.
Thanks.
I am also very satisfied with the gainpot on my build. When cranked it sounds not entirely unlike the sound of a simple class a tube amp at full tilt - even if it is maybe a bit more muddy (?)
Your question is interesting and I hope some of the tube experts will elaborate on the topic. I'd also like to add another question (since this thread is not sticktly on topic anymore anyway): Would it be possible to add a master volume onto the output of a class a amp similar to the master volume in the valve caster circuit ? Maybe we could have some of you tell us more about pot placements in valve circuits in general ?
Quote from: Caferacernoc on February 01, 2008, 11:15:13 AM
(The gain pot is) in a location that controls bias and feedback as well as gain.... It seems a better place for it would be in between the gain stages like a regular tube pre amp.
Thanks.
I think that the most flexible arrangement would be to have volume, bias and feedback adjustments for each gain stage, but if you made a normal pre-/amp that way you'd end up with so many controls that it would take ages just to discover all the possible settings, let alone remember which ones you liked. So you use a lot less controls than that, and decide what sort of flexibility you're most willing to give up.
If you put the pot between stages, you have eliminated the possibility of ever changing the bias or feedback in the first stage; it will always be exactly as warm/cool, and as clean/dirty (for a given volume level) as you've made it. All you can do is to make it quieter or louder. Fortnately, this should also let you control clipping of the second stage, assuming you provided enough overall gain. But you are narrowing down the possible voices of the effect to a certain range. This isn't necessarily a bad thing. If clean sounds like a '61 Fender Deluxe's clean, and boosted sounds like a cranked '61 Deluxe, maybe that is exactly what you want. If nothing else, it eliminates tons of ugly sounding settings that might otherwise have been available. But if you made it to sound like a '61 Deluxe, and the user happens to hate that tone, they're just outta luck.
If you leave the pot where it is, you CAN change bias and negative feedback along with volume, but you can only change all three at once. It gives one a wider range of tones to pick from, but it may be that you don't care for most of those tones, and can't arrive at some you'd prefer. Maybe it now ranges from clean Deluxe, to cranked Marshall 18, to distortion monster created by the gods of metal, and you can no longer get to the cranked Deluxe sound at all.
So it just depends on what you're after. Every guitarist's ideal setup would probably be a little different.
Hi
QuoteIf you put the pot between stages, you have eliminated the possibility of ever changing the bias or feedback in the first stage; it will always be exactly as warm/cool, and as clean/dirty (for a given volume level) as you've made it.
I'd suggest that you haven't really eliminated the opportunity for a bias change. It just requires one resistor to be changed, or a trimpot to be adjusted. And amps have the bias set, so unless there's a problem with every tube amp out there, there's not much of a problem with setting the bias to a "sweet" value and leaving it there.
A small value cathode resistor (1k) seems to work for 12AU7s, so a small resistor (470 ohms) and a trimpot of 1k would seem ideal. Large cathode resistance (e.g. 10k) is only likely to give low gain, and eliminate much of the "overdrive" effect. Personally, I would also keep any pot between stages 1 and 2 cranked, so it might as well be wired direct.
Again, this works well, IMO :
(http://www.aronnelson.com/gallery/d/18565-1/Triode+triode.jpg)
Just my 2c.
cheers
Quote from: brett on February 02, 2008, 07:57:20 AM
Hi
QuoteIf you put the pot between stages, you have eliminated the possibility of ever changing the bias or feedback in the first stage; it will always be exactly as warm/cool, and as clean/dirty (for a given volume level) as you've made it.
I'd suggest that you haven't really eliminated the opportunity for a bias change.
Sorry, I guess I was unclear.
You've made it impossible for a normal user, who only opens cases when they need to change batteries. If you're the guy holding the soldering iron, anything's possible.
you could also parallel a cap (.68 - 25uf) with R3 and use a switch to cut it in/out for more gain.
To anyone who's built this circuit -- stick a boost in front!
I added a mosfet boost circuit before the start of the tube boost and the result is a much more pleasing breakup than the gain pot provides. It also seems to make the tube boost more humbucker friendly. Cranking both the boost and the gain gives a fat saturated tone that I totally dig. Adding the boost was enough for me to decide that this circuit deserves an enclosure and a spot on my pedalboard ;D
Quote from: andrew_k on February 02, 2008, 05:10:19 PM
To anyone who's built this circuit -- stick a boost in front!
I added a mosfet boost circuit before the start of the tube boost and the result is a much more pleasing breakup than the gain pot provides. It also seems to make the tube boost more humbucker friendly. Cranking both the boost and the gain gives a fat saturated tone that I totally dig. Adding the boost was enough for me to decide that this circuit deserves an enclosure and a spot on my pedalboard ;D
Out of curiosity what boost did you use? Maybe a sound sample if you have time?
Thanks!
The boost I used is a SHO, because I had one in my pile of circuits and the only other boost I had floating around was an EH LPB that I don't like.
I'll look into a sample; unfortunately I'm having some massive issues with pro tools and OS X and pretty much can't use pro tools at all at the moment. ARRRGH.
Cool Andrew_K! Are you planning to box the booster in the same chassis and have a separate switch for the boost ckt?
Sorry to hear about your recording setup woes... hope you get it fixed soon!
Hi
Any booster with about 10dB of gain will be fine. The Stratoblaster booster, which gives pleasant boost of up to about 15dB, is nice.
cheers
Quote from: tranceracer on February 03, 2008, 12:54:39 AM
Are you planning to box the booster in the same chassis and have a separate switch for the boost ckt?
Same box, but no separate switch. It'll just be a pre-gain control or similar. With the tube laying flat between the 3PDT and the pots, it all fits nicely in a hammond BB.
Hey, I noticed that in the layout it wasn't stated that C3 is electrolytic, as far as I remember it is an electrolytic in the schematic..Should it be a big trouble to put an unpolarized cap or it has to be polarized??? ???
Unpolarized is fine.
I don't think you'll find many situations where a polarized cap is required. They're cheaper, and that can matter, but unpolarized will usually work in their place.
'k, thx!!! ;)
All right, I used a non polarized then...
I built it today...It was a little more difficult than I believed...A lot of wiring and my wiring isn't the best, maybe I am ok in on board wiring but there is NO board here, so... ;D
Anyway, I enjoyed my rendition, but I believe I went something wrong, maybe...It sounds quite good, it gives a nice bluesy sound but a little less distorsion compared to the video I saw on youtube...When it's engaged, there is a bloody background noise...Also, the LED doesn't light...Maybe I swapped the wires (LED-ground?)
I'll post some pics tomorrow...
EDIT: The valve lights up very little...It's an EH 12AU7
Wild guess: earthing problem.
Try gounding everything to 1 point (easily said, sometimes difficult to do)
Quote from: Renegadrian on February 13, 2008, 09:12:58 PM
EDIT: The valve lights up very little...It's an EH 12AU7
well, tubes arnt light bulbs
brett, I used the layout that I saw on the second page of this thread.
http://img292.imageshack.us/img292/1110/tubepedalpm0.jpg
Both IN and OUT sleeve have 4 ground wires connected...and one is the connection between them.
Any other clue? What about the LED??? I found that if I put the power plug just at the very beginning, the circuit still works and the LED lights...
I tried to put everything on vero, as suggested in the first pages...I should add the LED part...
Anyway, check if it's correct or there are errors in it...
(http://img101.imageshack.us/img101/3442/valvecasterdg2.th.jpg) (http://img101.imageshack.us/my.php?image=valvecasterdg2.jpg)
I solved the LED thing, it wasn't made to be soldered to the free lug, but together with the positive...
I made a gallery for your curiosity...
http://web.tiscali.it/renegadrian/
I used a TEKO case, which has enough room for the valve and all the pieces...I built a "wall" for the tube with wood...I triple checked its measures and cut it to totally fit in - I was going to glue it, but it's not necessary. I made two holes, one that contains the tube socket (then glued in) and another one for the wires. I also made two "peepshow" holes in the enclosure just above the tube...
I just need to fix the paint inperfections, put some labels on and clear coat...But well, that's it...
Looks good ;)
Can this be biased to use an 12AX7?, with more gain obviously... It's a very nice build!, I have to try it but I have only 12AX7's handy...
i have a spare 12ax7 laying around, I tried it but the result is not the best...As you haven't got a good voltage that this valve needs, it sounds "boomy" and you can feel it's not the right choice...While the 12AU7 is good enough and can sound sweet with 9-12V
You may want to try Marsha Valve Tube, it uses a 12AX7 and it should be easy as this one, also it seems it's verified.
SCHEM (http://www.aronnelson.com/gallery/v/vanhansen/marshavalve_tube_02.gif.html) and VERO LAYOUT (http://www.aronnelson.com/gallery/v/Mihkels-layouts/MarshaValveTube.jpg.html?g2_imageViewsIndex=1)
This is my next one, i already have valve socket enclosure, so I just need some little pieces...AndI'm gonna try the same building process, with the same valve placement. (altough I regret that this 12AU7 doesn't light that much...)
Be sure to tell us how it sounds once you're done. :icon_wink:
Sure I'll do, I think I fell in love with valves...(after all, I built this Valvecaster on Valentine's...)
I ordered the bits I miss...Next week Marsha will be mine!!! (the circuit, not a woman...) :icon_lol:
Improved vero version of the Valvecaster...It should work, I optimized and completed the layout...
(http://img182.imageshack.us/img182/7794/valvecasterv02sj6.th.jpg) (http://img182.imageshack.us/my.php?image=valvecasterv02sj6.jpg)
That's nice.
If you want the tone pot to work the "normal" way (bass-left, treble-right) you should move C3 to lug 1.
I just built a Valvecaster driving an SHO. I have installed a 100K master volume pot in place of the 100K resistor on the output of the SHO. It is currently on the bread board but will soon be on the pedal board. I love the way the Valvecaster overdrives the SHO mosfet. I tried the SHO in front of the Valvecaster as well but I like it better the other way. If you crank up the gain on the SHO as well as the gain and level control on the VC there is plenty of gain to be had. All this is running on 9 volts. I am bypassing the Valvecaster gain pot with a 2.2nf cap. This helps maintain some brightness when the VC gain is turned down. For the input cap on the Valvecaster I am using a combination of caps to give me 2.7nf. This helps tighten up the bottom end. The tube is a nos 12au7. I have been playing with the cap values in this circuit for a week and it sounds awesome with my Strat now into my blackface Fender amp. Seems like there are endless tones to be had with this pedal. It cleans up well with the guitar volume as well.
Here's version 0.4 - removed unnecessary strips and optimized it again, tone now working the right way.
Should work...
Next is the MVT redrawn by me, it displays better in this layout...Credit obviously to the makers of the previous schem and layout...
(http://img183.imageshack.us/img183/9308/valvecasterv04yu8.th.jpg) (http://img183.imageshack.us/my.php?image=valvecasterv04yu8.jpg)(http://img301.imageshack.us/img301/3672/marshavalvetubeop6.th.jpg) (http://img301.imageshack.us/my.php?image=marshavalvetubeop6.jpg)
BTW, sorry for my ignorance...what is a SHO?! ???
Also, I know that there's ORMAN Tube Driver that's working on 9-12V, I found some good layout I'd be posting here...
Quote from: Renegadrian on February 17, 2008, 08:40:26 PM
Here's version 0.4 - removed unnecessary strips and optimized it again, tone now working the right way.
Should work...
Next is the MVT redrawn by me, it displays better in this layout...Credit obviously to the makers of the previous schem and layout...
(http://img183.imageshack.us/img183/9308/valvecasterv04yu8.th.jpg) (http://img183.imageshack.us/my.php?image=valvecasterv04yu8.jpg)(http://img301.imageshack.us/img301/3672/marshavalvetubeop6.th.jpg) (http://img301.imageshack.us/my.php?image=marshavalvetubeop6.jpg)
BTW, sorry for my ignorance...what is a SHO?! ???
Also, I know that there's ORMAN Tube Driver that's working on 9-12V, I found some good layout I'd be posting here...
Nice layout there...What is the second layout you posted.
SHO Super Hard On....made by Zvex
Chris, the second layout is based on the Marsha Valve Tube
SCHEM (http://www.aronnelson.com/gallery/v/vanhansen/marshavalve_tube_02.gif.html) and VERO LAYOUT (http://www.aronnelson.com/gallery/v/Mihkels-layouts/MarshaValveTube.jpg.html?g2_imageViewsIndex=1)
O very nice...
How is it?
Have to build it yet, got the parts on the way - I'll report it in some days...
Renegadrian: nice work on the vero layout; I might have to give that a try for my second build. Looks much easier to integrate with a boost circuit. My current favorite setup for this circuit is a medium gain jfet boost before and another after. The first one heats up the signal a little for the tube and the second one gets slammed by the tube boost. I also like a mosfet boost before the tube boost, but I haven't tried one after yet.
I was having a problem with mine whereby it would cut in and out, with an audible pop as it was cutting out. The solution for me has been running it at 12v.
I ran it for over an hour last night at 12v with no problem, where as at 9v it starts popping and dying within 2 minutes. It might just be the tubes, but I tried a couple of different ones and the result was the same.
Andrew thank you for your kind words, I'm just a noob and I found it a good exercise to do, now I know a little more...
I will build another one, gotta try the inside fet boost!!! ;)
I have had mine running on 9 volts for at least 20 hours with several different 12au7's. So far I have had no problems. The tubes are all NOS though.
Quote from: Ripdivot on February 18, 2008, 08:01:00 PM
I have had mine running on 9 volts for at least 20 hours with several different 12au7's. So far I have had no problems. The tubes are all NOS though.
Yeah, it's probbly the tubes I'm using -- what do you expect for $1 for two off fleaBay ;)
Just built the vero version, still gotta tweak it a bit, but noticed two minor mistakes in it. C3 should be 1uF instead of 1nF, and you forgot to mention that pin 4 should be grounded. It's pretty obvious when looking at the schematics but still..
Aren, thx for pointing out those errors, so here is version 0.5!!! (should be final...)
(http://img155.imageshack.us/img155/3599/valvecasterv05qs5.th.jpg) (http://img155.imageshack.us/my.php?image=valvecasterv05qs5.jpg)
Hey, post some pics of your version!!! I'll be glad to see them!!!
Based on the Twincaster schem, seen some pages ago and developed by Dano (again) I'd like to show you my Twincaster VERO version...
Here is my vero (should be correct, but hey...)
(http://img220.imageshack.us/img220/460/twincasterv01yq0.th.jpg) (http://img220.imageshack.us/my.php?image=twincasterv01yq0.jpg)
Will do, as soon as I get it up and running. Right now it doesn't work at all, seems like bad contacts somewhere, but I can't seem to locate the source of the problem...
Since every time i report a non-working build in this forum I figure it out in ten minutes, I'll try this method again... :)
All I get is some ground hum (which is strange, since it is pretty much star-grounded) but no real signal. Any idea what can be wrong there?
I messed with the connections, and it moved between no sound it all, only ground hum, hum+signal and clean signal. After a while it settled on "hum alone" and I can't seem to find the source of the problem...
Well, it can be a 100's problems...Grounding-some connection you just forgot-bad valve-really bad DC adapter...Dunno... ???
Well, as expected, it started working 10 seconds after posting ;D
There is still a ground hum, but that I can fix...
If I only knew what I did to get it working...
I just build version 5 and it works!
Wired direct without a switch, but will add soon. Great layout. I did revert back to the earlier version that had the 8 pin lineup on the board. I just corrected the parts layout. Thanks for putting the layout together.
Oh man, that's great!!! What if I tell you it's my first vero layout I design?!?! I am so happy it worked!!! Time for another beer then!!! :icon_wink:
I just fell in love with those valve projects...I will be buiding marsha, then Orman tube driver and I'll try the Twincaster (valvecaster with 2 valves)
Did you put your creation in some enclosure!? Pics are welcome, as for Aren!!!
PS a big thank you goes to Dano, he started it all...
Just wired up the switch and everything works great. I don't have a 100k pot for the gain as I didn't have any 50k. I want to see if I can tame the gain a bit. Its capable of some decent amounts of gain. I am a couple weeks away from creating an enclosure. I want to come up with something good for my first tube build
Echo your sentiments, Thanks to all on the thread.
It's still VERY unstable (I'm beginning to think the volume pot should be replaced), but here's the pic:
http://picasaweb.google.com/lh/photo/gSqPT9t6cpgypPkAKZsVdg (http://picasaweb.google.com/lh/photo/gSqPT9t6cpgypPkAKZsVdg)
It's my first attempt to use the "dark t-shirt transfer paper" (with the aid of my beautiful talented wife ;)).
The actual box was painted with regular acrylic paint and finished with water-based clear coat.
This is getting weird.
I replaced the pot, and it did improve the stability issues. Worked great, only had this annoying buzz in the background. Since I eliminated the possibility of a ground loop, I decided I would try and stabilize the power supply by adding a 180ohm resistor in series with the DC jack. It stopped working altogether, so I measured the power at the DC node. It was 2.53V! :o Once I disconnected the resistor from the vero, and measured it with no load, I got 15.3V, so the resistor is fine.
Any thoughts?
"Just wired up the switch and everything works great. I don't have a 100k pot for the gain as I didn't have any 50k. I want to see if I can tame the gain a bit. Its capable of some decent amounts of gain. I am a couple weeks away from creating an enclosure. I want to come up with something good for my first tube build"
To tame the gain I would lower R2 and R3. 220k and 100k seem pretty high for a low voltage circuit. Even in a regular high voltage amp the normal value is just 100k. So maybe cut them in half.
if you bring down that 220k to 100k it will def lower the gain a bit. I built mine with both plate r's at 100k.
Thanks for the replies. I may try and add a toggle switch to have the higher gain setting available. I will give that a shot and report back
Quote from: gluedtogether on February 19, 2008, 08:12:03 PM
I want to see if I can tame the gain a bit.
hehe, I did the complete opposite. A 1M gain pot allows massive, saturated gain. A little mushy in the bass frequencies, but pretty cool. I'm considering putting a "more" switch in, whereby it adds a resistor in series to the regular gain pot.
Going from 50K to 1M...Hell, now that's a big difference!!! So it gains more gain?! :icon_mrgreen:
And for what I understood...higher resistance value = more gain?
gotta try this pot change...what about 100K or 500K???
Just built my 3rd valvecaster. My first one was for me, and the first time I brought it to a rehearsal, my buddy asked me for one. I made him one, and his brother wanted one :P.His brother actually offered to pay for it!
Long story short, these things rock!
Quite a thread we got going here aswell. I looked back to my first posts on this thread way back, and I realized this thread is what prompted me into building tube amps. 2 amps and 3 Valvecasters later, I finally feel like I know a thing (maybe 2) about tubes.
Zach
Oh, and by the way, I had my friend bring his to a rehearsal, and afterwards, we got it set up with a switch that cuts all the gain directly to clean boost. I brought my meter, and about 50 resistors valued 1ohm to about 15k. We figured out where the maximum clean headroom with his main axe on full volume was, I measured it, and ended up putting in a 12k resistor, and added a stomp switch for clean boost (did I mention I brought my drill aswell ;D).
Zach
Quote from: Renegadrian on February 20, 2008, 06:16:40 PM
And for what I understood...higher resistance value = more gain?
It would seem that's the case. I'm a newbie too, so I just mess with things until I break it or it sounds cool :D
I'm a little concerned about the affect an increased gain would have on tube life. Maybe one of the more experienced guys can chime in here...?
After experimenting with all sorts of boosts before and after, I'm going to box mine up without any extra gain stages (maybe a high impedance buffer at input to retain more sparkle, I'll be testing that on the weekend). If I want more gain I'll just use another boost or OD pedal before or after the tube drive.
I'll give about 90% confidence on this one...so don't be mad if im wrong ;D
I don't believe the added gain will do anything to tube life, at least on a measureable scale. Keep in mind, these things are designed to run more than 10-20 times as much voltage as you are running here. If theres anything that is going to reduce tube life here, it is the fact that you are running them on suck low voltage, which (I believe) causes stripping, and decreases life.
So, unless anyone corrects me otherwise, go ahead. Build a gain monster!
Zach
I added a 7812 regulator, and it now works like a charm!
Makes my acoustic sound half decent when going direct! ;)
Quote from: Zben3129 on February 20, 2008, 06:32:38 PM
Oh, and by the way, I had my friend bring his to a rehearsal, and afterwards, we got it set up with a switch that cuts all the gain directly to clean boost. I brought my meter, and about 50 resistors valued 1ohm to about 15k. We figured out where the maximum clean headroom with his main axe on full volume was, I measured it, and ended up putting in a 12k resistor, and added a stomp switch for clean boost (did I mention I brought my drill aswell ;D).
Zach
How did you wire it?
running the heaters at above or below the required voltage will do harm to the tube over time. I wouldn't use any of your NOS super mojo tubes in this design unless you run the heaters at 12v.(or 6v if using pins 4+5 and 9).
Quote from: kurtlives on February 20, 2008, 07:50:07 PM
Quote from: Zben3129 on February 20, 2008, 06:32:38 PM
Oh, and by the way, I had my friend bring his to a rehearsal, and afterwards, we got it set up with a switch that cuts all the gain directly to clean boost. I brought my meter, and about 50 resistors valued 1ohm to about 15k. We figured out where the maximum clean headroom with his main axe on full volume was, I measured it, and ended up putting in a 12k resistor, and added a stomp switch for clean boost (did I mention I brought my drill aswell ;D).
Zach
How did you wire it?
Sorry if this is wrong, I'll go look at the schem in a minute...
but I just used a spdt, pin 3 of 12au7 going to middle lug of switch, one side of switch had pot, the other had the 12k
Zach
Adding resistance to the plate resistors(R1 and R2) will increase gain. Adding resisitance to VR1, in series with the gain pot, will decrease gain.
Hmmm...
I didn't have the schematic with me, all I know is I used a spdt somehow and a 12k resistor.
Maybe it was "after the pot" to the middle lug, one side going to ground and the other to a 12k to ground.
Zach
For the benefit of Mr. Chawk (and anyone else who wants to build this thing), here are some gut shots of the point to point version of the Valvecaster. Please note that this was done quickly and eagerly, so the soldering is rather crappy. :icon_wink:
(http://i47.photobucket.com/albums/f191/krinor/Valvecastergut4.jpg)
(http://i47.photobucket.com/albums/f191/krinor/Valvecastergut3.jpg)
(http://i47.photobucket.com/albums/f191/krinor/Valvecastergut2.jpg)
(http://i47.photobucket.com/albums/f191/krinor/Valvecastergut1.jpg)
NICE SHOTZ!!!
Fantastic!!! Much thanks! :D
Quote from: Krinor on February 21, 2008, 03:39:05 PM
so the soldering is rather crappy. :icon_wink:
if that's what counts as crappy, then I got a LOTTA catching up to do.
I knocked this up today to have a play with the circuit. Looking around the net I found a few tube circuits in the same vien and this board is enitirely plug and play to allow maximum tweekage. Me and her are gonna get real aquanted over the next few weeks :) (sorry, hill billy mode)
(http://www.dryroasted.f2s.com/vc1.jpg)
<edit> Yes I know it shpuld be a glass of JD and coke for the full rock n roll kudos but hey, i'm English :D
Now that's nice and clean!
Be sure to post your findings here (once you get to know her).
And I thought englishmen only drank tea ? ;)
Well, There's the Ruby Tuby (http://www.sophtamps.ca/schematics/ruby_tuby_1.jpeg), both preamp or full amp - and other sophtamps creations...Sad I suck at reading schematics...
If I only find vero/perf/pcb of any of these...
Hmmpf... I would just replace the opamp stage with a JFET buffer, stick the Valvecaster in front of it, and feed it to a 386 amp.
Seems easier...
Quote from: Renegadrian on February 21, 2008, 06:38:55 PM
Well, There's the Ruby Tuby (http://www.sophtamps.ca/schematics/ruby_tuby_1.jpeg), both preamp or full amp - and other sophtamps creations...Sad I suck at reading schematics...
If I only find vero/perf/pcb of any of these...
Surely you are aware of Dano's "Tube Cricket" ? That one seems like a logic progression from the Valvecaster.
First observations from the valvecaster test rig:
Using a 12AX7 at 12V and no tone stack, everything else stock - a bit "wooly" for my liking not alot of note defination, a bit boomy (this is coming from a confirmed metal head). Change the input cap (C1) to 22nF and its a whole new game. Lots of ACDC-esque tone, lovely response and works well with humbuckers (no idea about single coil).
Next up, same as above but changed R3 from 100K to 240K and moved VR1 from the leg of tube pin 3 to pin 8 and jumpered pin three to ground - Not a masive change but enough to give a noticable comparison. Most obvious thing is the response of the gain control VR1, before, most of the control was in the last 1/4 turn but now its more evenly spread. Overall tone remains useable.
Cleaning up the tube boost - these were quotes from this thread
"To tame the gain I would lower R2 and R3. 220k and 100k seem pretty high for a low voltage circuit. Even in a regular high voltage amp the normal value is just 100k. So maybe cut them in half."
"if you bring down that 220k to 100k it will def lower the gain a bit. I built mine with both plate r's at 100k. "
"but I just used a spdt, pin 3 of 12au7 going to middle lug of switch, one side of switch had pot, the other had the 12k"
I am going to get the iron ready today to try some of these. I was planning on putting a dpdt switch in for R2 to go between 220K and 100K based on the recomendations above. Then I saw the idea to put a spdt switch between the gain pot and pin three. I am starting to follow where lowering the resistance will cause the pedal to be a bit more clean. Given the two options, which one will provide a cleaner setting? I like the idea of being able to toggle between a cleaner sound and an overdrive sound. I am not so clear on the different roles of each pin of the tube so I don't know if changing the value going to pin 3 vs pin 5 will do this.
Thanks to all for the suggestions
Okay, here's another little mod for the Valvecaster:
A usefull tonal variation can be achieved by implementing a switchable negative feedback.
Put a 22k resistor and a spdt switch between the output and the cathode of the second stage (lug 8 ).
You can also make a "bass boost" filter out of it by inserting a capacitor between there as well.
I currently have a 0.056uF cap in series with the resistor. This removes some of the mid range and helps keep things a little bit more together. It sounds nice and clean at low gain settings and it also sounds pretty good with everything maxed. More defined puch in the bottom and not so shrill. I've tried this with larger caps as well but it tends to get a bit too boomy.
All in all this is a nice little mod which will tame the gain a bit. Nothing dramatic, but it helps if you want to tune the thing for a more clean boost.
Here's an illustration:
(http://i47.photobucket.com/albums/f191/krinor/Valvecastergut1highpass.jpg)
Any preferences in brand name of AU7 tube used?
Examples:
Electro-Harmonix
EH Gold
Mullard
Sovtek
Tesla
Sino-China
Odd Ball
Personally I don't use EH anymore after discovering how much better almost anything else sounds. :icon_twisted:
I currently use a brand called Tube Amp Doctor. They sound very transparent and are a bit on the treble side of the scale.
Tung Sol and JJ would be excellent choices.
I gave that a shot. It cleaned up it pretty good. I am going to play around with that for a bit before trying any of the other gain reducers. I like the bass increase by switch, but may change the value to reduce the bass a bit
Thanks
Quote from: Krinor on February 22, 2008, 10:29:35 AM
Okay, here's another little mod for the Valvecaster:
A usefull tonal variation can be achieved by implementing a switchable negative feedback.
Put a 22k resistor and a spdt switch between the output and the cathode of the second stage (lug 8 ).
You can also make a "bass boost" filter out of it by inserting a capacitor between there as well.
I currently have a 0.056uF cap in series with the resistor. This removes some of the mid range and helps keep things a little bit more together. It sounds nice and clean at low gain settings and it also sounds pretty good with everything maxed. More defined puch in the bottom and not so shrill. I've tried this with larger caps as well but it tends to get a bit too boomy.
All in all this is a nice little mod which will tame the gain a bit. Nothing dramatic, but it helps if you want to tune the thing for a more clean boost.
Quote from: gluedtogether on February 22, 2008, 03:38:02 PM
I gave that a shot. It cleaned up it pretty good. I am going to play around with that for a bit before trying any of the other gain reducers. I like the bass increase by switch, but may change the value to reduce the bass a bit
Thanks
You can probably go down to 0.033uF and still keep some of the bass boost effect. Or leave the capacitor out and use only the resistor as an ordinary feedback loop. You may also like other resistor values. I tried 10k too but ended up using 22k. Seems like tubes can take a real beating no matter what you throw at them. And what we are dealing with here is just some gentle cuddling anyway. :icon_wink:
Could someone tell me how it would affect the biasing of the second stage if I put in a 1,5k resistor to ground on the cathode (lug 8 ) ?
By the way - I'm not sure how many of you are into recording, but I just tried this circuit as a mixing tool, and it works fantastic.
I ran a bass track through it, and while it didn't sound that great on its own, when combined with the original clean signal it sounded great. Same deal on vocals that were too thin for my taste.
Quote from: Aren on February 22, 2008, 03:54:22 PM
By the way - I'm not sure how many of you are into recording, but I just tried this circuit as a mixing tool, and it works fantastic.
I ran a bass track through it, and while it didn't sound that great on its own, when combined with the original clean signal it sounded great. Same deal on vocals that were too thin for my taste.
Done that yes. I use it for all kinds of things. Works good with vocals. Nice to enhance things with, especially with some gain reduction as mentioned above.
I might try leaving the cap and using the switch to just add a bit more bass, might even keep the current value. After playing with it a bit more, I think I might trying cleaning up the gain with a second footwitch with the resitor on pin 3 and see how that sounds. I think it would be nice to have the versatility to kick the gain on when needed. This has been a good circuit to experiment on.
Thanks
[/quote]
You can probably go down to 0.033uF and still keep some of the bass boost effect. Or leave the capacitor out and use only the resistor as an ordinary feedback loop. You may also like other resistor values. I tried 10k too but ended up using 22k. Seems like tubes can take a real beating no matter what you throw at them. And what we are dealing with here is just some gentle cuddling anyway. :icon_wink:
Could someone tell me how it would affect the biasing of the second stage if I put in a 1,5k resistor to ground on the cathode (lug 8 ) ?
[/quote]
Without the capacitor it will just be an ordinary global negative feedback as seen in many old class A amps (Fender champs etc). Leaving it out will just flatten things out a little. But that's probably what yo were after anyway.
How about putting a 50k pot in there instead and tweaking it until you find the optimal setting ? (And then measure the resistance and report back to us of course :icon_wink: )
Quote from: Chawk on February 22, 2008, 11:59:28 AM
Any preferences in brand name of AU7 tube used?
Examples:
Electro-Harmonix
...
Well, I have an EH in and my Valvy doesn't sound as expected, I know everyrthing's ok so I am surely going to try another brand to make it sound better, maybe jj or anything I could find on evilBay...For this little esperience of mine, EH are a no-no, also I read bad comments elsewhere on the forum, so...
[opinion/]
Those comments you read are correct, in my mind.
I've got 2 EH 12au7, and they sound sterile, crappy, plain old bad. In fact every EH tube I have tried sounds like this, unfortunately.
I've still got some baldwin's, and just got a bunch of conn's, and they both sound WAY better. I believe they are RCA made, judging by looks?
[/opinion]
Zach
For an excellent range of tubes try these guys:
http://www.tubedepot.com/index.html
Tube Depot are great! No "hidden" fees for orders, you get what you pay for with no additional charges other than the usual shipping.
I can think of at least one tube store that could learn from them.
Quote from: Caferacernoc on February 21, 2008, 02:25:36 PM
Adding resistance to the plate resistors(R1 and R2) will increase gain. Adding resisitance to VR1, in series with the gain pot, will decrease gain.
As I am on the "MORE GAIN" party, I think I'll do a vero version socketing the above mentioned R1 and R2 trying some increased values, also swapping some gain pots, like 100k, 250k, 500k...
It should "gain" some gain that way, am I right?!
Quote from: Renegadrian on February 23, 2008, 07:34:28 PM
Quote from: Caferacernoc on February 21, 2008, 02:25:36 PM
Adding resistance to the plate resistors(R1 and R2) will increase gain. Adding resisitance to VR1, in series with the gain pot, will decrease gain.
As I am on the "MORE GAIN" party, I think I'll do a vero version socketing the above mentioned R1 and R2 trying some increased values, also swapping some gain pots, like 100k, 250k, 500k...
It should "gain" some gain that way, am I right?!
Yup. The ultimate tweaker box would probably be to replace the plate resistors with 250k pots. Then put a 1k resistor on the collectors to ground. Bypass each collector resistor with a 5uf capacitor. Put the 50k "gain" pot in series with the bypass capacitor. And dial it in!
Quote from: Caferacernoc on February 25, 2008, 12:47:21 PM
Quote from: Renegadrian on February 23, 2008, 07:34:28 PM
Quote from: Caferacernoc on February 21, 2008, 02:25:36 PM
Adding resistance to the plate resistors(R1 and R2) will increase gain. Adding resisitance to VR1, in series with the gain pot, will decrease gain.
As I am on the "MORE GAIN" party, I think I'll do a vero version socketing the above mentioned R1 and R2 trying some increased values, also swapping some gain pots, like 100k, 250k, 500k...
It should "gain" some gain that way, am I right?!
Yup. The ultimate tweaker box would probably be to replace the plate resistors with 250k pots. Then put a 1k resistor on the collectors to ground. Bypass each collector resistor with a 5uf capacitor. Put the 50k "gain" pot in series with the bypass capacitor. And dial it in!
Let me revise that slightly:
Replace the plate resistors with 250k pots. Then put a 10k resistor on the collectors to ground. Bypass each collector resistor with a 1uf capacitor. Put a 5k "gain" pot in series with the bypass capacitor. And dial it in!
Quote from: Caferacernoc on February 27, 2008, 05:25:03 PM
Quote from: Caferacernoc on February 25, 2008, 12:47:21 PM
Quote from: Renegadrian on February 23, 2008, 07:34:28 PM
Quote from: Caferacernoc on February 21, 2008, 02:25:36 PM
Adding resistance to the plate resistors(R1 and R2) will increase gain. Adding resisitance to VR1, in series with the gain pot, will decrease gain.
As I am on the "MORE GAIN" party, I think I'll do a vero version socketing the above mentioned R1 and R2 trying some increased values, also swapping some gain pots, like 100k, 250k, 500k...
It should "gain" some gain that way, am I right?!
Yup. The ultimate tweaker box would probably be to replace the plate resistors with 250k pots. Then put a 1k resistor on the collectors to ground. Bypass each collector resistor with a 5uf capacitor. Put the 50k "gain" pot in series with the bypass capacitor. And dial it in!
Let me revise that slightly:
Replace the plate resistors with 250k pots. Then put a 10k resistor on the collectors to ground. Bypass each collector resistor with a 1uf capacitor. Put a 5k "gain" pot in series with the bypass capacitor. And dial it in!
When you say "collector," you're really talking about "cathode," right? (or kathode if you prefer)
Quote from: DryRoasted on February 22, 2008, 09:21:54 AM
First observations from the valvecaster test rig:
Using a 12AX7 at 12V and no tone stack, everything else stock - a bit "wooly" for my liking not alot of note defination, a bit boomy (this is coming from a confirmed metal head). Change the input cap (C1) to 22nF and its a whole new game. Lots of ACDC-esque tone, lovely response and works well with humbuckers (no idea about single coil).
So you say it works well with a 12AX7 too? Did you try to increase R1 and R2 values, as well as the GAIN pot value???
We already said it is "gainier" with increased values of the above...
Quote from: earthtonesaudio on February 27, 2008, 06:19:51 PM
Quote from: Caferacernoc on February 27, 2008, 05:25:03 PM
Quote from: Caferacernoc on February 25, 2008, 12:47:21 PM
Quote from: Renegadrian on February 23, 2008, 07:34:28 PM
Quote from: Caferacernoc on February 21, 2008, 02:25:36 PM
Adding resistance to the plate resistors(R1 and R2) will increase gain. Adding resisitance to VR1, in series with the gain pot, will decrease gain.
As I am on the "MORE GAIN" party, I think I'll do a vero version socketing the above mentioned R1 and R2 trying some increased values, also swapping some gain pots, like 100k, 250k, 500k...
It should "gain" some gain that way, am I right?!
Yup. The ultimate tweaker box would probably be to replace the plate resistors with 250k pots. Then put a 1k resistor on the collectors to ground. Bypass each collector resistor with a 5uf capacitor. Put the 50k "gain" pot in series with the bypass capacitor. And dial it in!
Let me revise that slightly:
Replace the plate resistors with 250k pots. Then put a 10k resistor on the collectors to ground. Bypass each collector resistor with a 1uf capacitor. Put a 5k "gain" pot in series with the bypass capacitor. And dial it in!
When you say "collector," you're really talking about "cathode," right? (or kathode if you prefer)
Yes. I goofed up my tube with my transistor lingo!
Some pictures of my latest Valvecaster. This time with true bypass in a small enclosure.
I wired it so that the input jack functions as an on/off switch for the tube (on if jack is inserted). Thus the tube will stay on all the time for imediate action once the effect is engaged.
(http://i47.photobucket.com/albums/f191/krinor/Valvecasterrd1.jpg)
And the interior:
(http://i47.photobucket.com/albums/f191/krinor/Valvecasterinterir.jpg)
Man, I just love your pedal!!! Nice and classy!!! Is it the standard version or it has some mods!?
Standard. I really love it the way it is. But I AM going to build a twin version soon. Just have to sell this one first to get some cash for more tubes. :icon_mrgreen:
+1 on the twincaster, I am waiting my tubes to arrive, an angel sent me some for free...And then I'll go twin too!!!
Will post asap the results...
Please do :icon_wink:
Quote from: Krinor on March 09, 2008, 05:13:47 PM
Some pictures of my latest Valvecaster. This time with true bypass in a small enclosure.
I wired it so that the input jack functions as an on/off switch for the tube (on if jack is inserted). Thus the tube will stay on all the time for imediate action once the effect is engaged.
(http://i47.photobucket.com/albums/f191/krinor/Valvecasterrd1.jpg)
And the interior:
(http://i47.photobucket.com/albums/f191/krinor/Valvecasterinterir.jpg)
That is a great piece of work, inside and out. I'm a sucker for chrome/polished metal :)
Good job!
Thanks Dano!
Actually (admittedly) much of my work is inspired by all the cool stuff on your amazing website! :icon_wink:
+1
thanks to you for your circuit, we enjoyed it so much, as you can see...
Quote from: Krinor on March 09, 2008, 06:02:37 PM
Thanks Dano!
Actually (admittedly) much of my work is inspired by all the cool stuff on your amazing website! :icon_wink:
My pleasure. Wait until you see the latest project. :icon_twisted: :icon_twisted: :icon_twisted:
Quote from: dano12 on March 09, 2008, 06:07:32 PM
Quote from: Krinor on March 09, 2008, 06:02:37 PM
Thanks Dano!
Actually (admittedly) much of my work is inspired by all the cool stuff on your amazing website! :icon_wink:
My pleasure. Wait until you see the latest project. :icon_twisted: :icon_twisted: :icon_twisted:
Oh crap! What have you been up to now ?! :icon_lol:
Quote from: Krinor on March 09, 2008, 06:14:42 PM
Quote from: dano12 on March 09, 2008, 06:07:32 PM
Quote from: Krinor on March 09, 2008, 06:02:37 PM
Thanks Dano!
Actually (admittedly) much of my work is inspired by all the cool stuff on your amazing website! :icon_wink:
My pleasure. Wait until you see the latest project. :icon_twisted: :icon_twisted: :icon_twisted:
Oh crap! What have you been up to now ?! :icon_lol:
Microprocessor-controlled LFO/sequencer. Finished the basic coding tonight. Now its on to polishing and debugging.
Now THAT is beyond that piece of grey fat which I laughingly call my brain. :icon_mrgreen:
Here is the schematic for my latest dual 12AU7 circuit. It is currently still on the bread board and I think it sounds great. It is designed to run on 9 volts. It goes from clean boost all the way up to "brown" type gain. It cleans up nice with the guitar volume as well.
(http://img80.imageshack.us/img80/8932/lvlrev3bmprk9.th.png) (http://img80.imageshack.us/my.php?image=lvlrev3bmprk9.png)
Quote from: Krinor on March 09, 2008, 05:13:47 PM
(http://i47.photobucket.com/albums/f191/krinor/Valvecasterrd1.jpg)
And the interior:
(http://i47.photobucket.com/albums/f191/krinor/Valvecasterinterir.jpg)
Kristian,
That pedal is tight! You've got some of the slickest looking boxes. Post some sound clips of this beauty... I just picked up some 12AU7s and was thinking of building it.
Matt
Thanks Matt. :icon_cool:
I built this today with a 12au7. I would post pictures, but it looks identical to Kristian's. (Sorry, I liked the look and the layout)
I like it. It's definitely vintage-y. It drives a solid state smoothly, and it makes my Fender Bronco (Vibro-champ) sounds downright nasty.
One thing, though, do any of you guys have that scratch on your gain pot that sounds like DC?
--Cory
Following my layout below, how do I get rid of the tone control? Shall I have to leave out only C4 or both C3 and C4?
Also, do you think that the tone control below I found at Dano site would work better???
(http://beavisaudio.com/Projects/BigMuffToneControl/BodyOnPot.gif)(http://img361.imageshack.us/img361/3889/valvecasterv05sv9.th.jpg) (http://img361.imageshack.us/my.php?image=valvecasterv05sv9.jpg)
Also, I'd really love to see the schematics of those shiny boxes...Look at specs...Guess what kind of tube they use^!?
http://www.voxamps.co.uk/pedals/cooltron.asp
Hi
that tone control may need a buffer before it, and (especially) a buffer after it. JFET buffers are simple and effective (4 parts!)
cheers
Just finished my Matsumin Tsunami Tube Overdrive! :D
The middle knob is just covering a hole I drilled for a different tone stack that didn't work. This is actually my 2nd revision back to the original schematic. Sounds great!
(http://i215.photobucket.com/albums/cc70/tr-stompboxes/MatsuminTubeOD.jpg)
Looking good!
Cool idea to put that japanese painting on it.
I'm thinking that maybe you could use that extra pot for some sort of sweepable feedback loop filter thingy ?
Thanks Krinor!
Great suggestion for the middle knob. That graphic actually came out that way by accident. Originally it was supposed to be color. The gory details are on the "Pictures!" thread. :D
This was just a prototype so you'll also notice an extra hole on the side. :icon_rolleyes:
The next one will be much cleaner (I hope) :icon_wink:
Put a switch in the extra hole to turn the sweepable filter on or off ! :icon_mrgreen:
Then sell it on ebay for loads of $$ :icon_twisted:
Is there any way to mod the Valvecaster so it sounds good with an active bass guitar?
I'd love to build this stuff, but I would also like to use it. :icon_wink:
Quote from: brett on March 11, 2008, 02:06:19 AM
Hi
that tone control may need a buffer before it, and (especially) a buffer after it. JFET buffers are simple and effective (4 parts!)
cheers
Ok - what about my other question - how do I get rid of the tone control? Shall I have to leave out only C4 or both C3 and C4 (and the pot, obviously...)?
Looking at the dual tube schematic, the stage between the two tubes, only C4 and VR2 are removed.
Quote from: dano12 on January 05, 2008, 04:36:19 PM
here's a rough, unverified splice of the schematic showing two tube stages:
(http://www.beavisaudio.com/Projects/ValveCaster/twincaster.gif)
C3 stays. That's a DC blocking capacitor. It has nothing to do with the tone control. Just remove C4 and the pot.
Its a very basic crude tone control.... And that does not make it bad, so don't read it like that.
I just built one of these....I am thinking if I build another one I will throw in a Fender tone-stack.
All right, thx for your explaination...I know it's just a basic tone, it might be a little useful or not...I'd like to try my next one without...
Also,I don't know how it sounds with active bass (don't own one) but sounds quite good with a passive one (maybe a littlle dark for my taste, but it's ok).
Quote from: Renegadrian on March 11, 2008, 07:38:24 PM
Also,I don't know how it sounds with active bass (don't own one) but sounds quite good with a passive one (maybe a littlle dark for my taste, but it's ok).
Allright then. That's gonna be my next build. Thanks! :)
p.s. could you record some samples?... TIA :icon_mrgreen:
Haven't got the bass at disposal (left it in my drummer's garage) so no samples...
Anyway, here's another 12V tube project...
http://paia.com/manuals/docs/9305-tubehead-manual.pdf
Quote from: Renegadrian on March 12, 2008, 12:42:02 PM
Haven't got the bass at disposal (left it in my drummer's garage) so no samples...
Anyway, here's another 12V tube project...
http://paia.com/manuals/docs/9305-tubehead-manual.pdf
The voltage from the Tubehead is multiplied to 42 volts.
Quote from: Salvatore on March 12, 2008, 02:05:55 PM
Quote from: Renegadrian on March 12, 2008, 12:42:02 PM
Haven't got the bass at disposal (left it in my drummer's garage) so no samples...
Anyway, here's another 12V tube project...
http://paia.com/manuals/docs/9305-tubehead-manual.pdf
The voltage from the Tubehead is multiplied to 42 volts.
Uh, didn't notice, my italian (I guess...) comrade...BTW it gets its power from an usual 12V wall wart...So it's a 12V project!!! :icon_wink:
Ok, :icon_lol:
I heard some positive things about the tubehead and with a few extra components it can be made into a mic pre as well.
At Tapeop there is an article with some mods to upgrade it for better specs.
Beware that the 12V wall wart is AC though, making a + -15V supply a bit like used in the Shaka Tube, an other very interesting low voltage overdrive.
i wonder what 3 of these in series would be like????
power 12v and heaters 12v
Okay, since nobody has posted soundclips of this thing yet, I thought I'd give it a shot. Apart from the obvious crappy playing I guess those who wonder how it actually sounds will at least get an idea. :icon_redface:
http://www.aronnelson.com/gallery/main.php/v/Krinor/Valvecaster+soundclip.mp3.html
Sounds good and bright! Did you mod it to get it to be more trebbly? Mine sounds more warm which work really well with rig.
Here's another sound clip buried on page 3 somewhere.
http://www.youtube.com/watch?v=cdcORgmfPl4
I'm hoping to put a sound clip of how my Matsumin sounds with my rig up soon just don't have time to make the recording right now.
Can I upload videos to the gallery or only sound clips?
Very nice, Krinor!
I've got some tube sockets on order, and I'm building this bad boy as soon as they arrive. :icon_mrgreen:
I found this Tuesday night and built it 24 hours later!!!!! Finished and debugged it last night, but It was too late to really rock out.
I need more gain, tonight Im going to change the plate resistors I think, any sudgested values???
Anyway, heres some pics of the first one. Next I will build a dual 6111 with the heaters in series powered off my 12.6 custom regulated wall wart.
(Needs a stompin switch, gotta order some)
(http://i23.photobucket.com/albums/b353/getpunched/DSC_0001.jpg)
(http://i23.photobucket.com/albums/b353/getpunched/DSC_0003.jpg)
(http://i23.photobucket.com/albums/b353/getpunched/DSC_0002.jpg)
Quote from: tranceracer on March 13, 2008, 02:36:35 PM
Sounds good and bright! Did you mod it to get it to be more trebbly? Mine sounds more warm which work really well with rig.
The reason why it sounds bright is that I have the tone control all the way on the treble side, and I've got a Jensen P8R (8") in my amp. The recording is done on a digital Boss recorder - that too makes things brighter than normal.
Edit: Nice shots there Forsakenrider. Welcome to the forum. :icon_biggrin:
forsakenrider and culturejam, welcome in the VALVECASTER fan club...I made one a month ago, but still it has some issues, mainly it has that "unregulated power" hiss...That annoys me so much, I have to put a 7812 inside that box...So up till then, no recordings or official pics
Kristian, nice sample track here... :icon_wink:
Dear Renegadrian, Check out this link: http://www.dxing.info/equipment/wall_warts_bryant.dx . Build it with a LM317 with a heatsink and you adjust your power output via trim pot and its got enough filtration for most applications. (It was literally night and day when I added it) Cheap and simple.
also, Have you tried changing any resistor values for higher gain? It sounds awesome when I crank the volume and gain to 10, but id like to be able to go past that and turn it down a bit as well...
I traced another low-voltage tube circuit recently.
http://www.diystompboxes.com/smfforum/index.php?topic=66061.0
quote forsakenrider
Dear Renegadrian, Check out this link: http://www.dxing.info/equipment/wall_warts_bryant.dx . Build it with a LM317 with a heatsink and you adjust your power output via trim pot and its got enough filtration for most applications. (It was literally night and day when I added it) Cheap and simple.
THANKS MY FRIEND, IT SEEMS A VERY USEFUL LINK!!!
also, Have you tried changing any resistor values for higher gain? It sounds awesome when I crank the volume and gain to 10, but id like to be able to go past that and turn it down a bit as well...
NOT FOR NOW, I JUST MADE THE VERO VERSION I LAYED OUT THAT YOU CAN FIND SOME PAGES AGO, I PUT SOCKETS FOR R1 AND R2 - I NEED THE OTHER PARTS. (I'LL GO BANZAI IN A COUPLE OF DAYS...)
Also, I was messing around with my Valvecaster, my "Stratoblastered" guitar and an AMZ mosfet booster - for now using the two boosters with the Valvecaster leads to horrible sound and too much distortion...I'll try again as soon as I will have a quiet V. per se...
Changing R1 and R2? Raising R1 above 1meg? Ive always seen it at 1meg in all the tube amp circuits. and raising R2, wont that lower the plate voltage? how does that increase the gain?
Another question i have is about the pots. Gain and Tone are not connected to ground in the layout but in the schematic they are, why is this?
Hi All!
I have viewed this topic some days, this schema is very cool, but I never find with change this schema for one clean sound, it is possible? how?
The clean sound would like a "preamp tube clean". Because, when "Gain" control is decrement in original schema, still have a little overdrive.
Thanks for all, sorry for my beginner question.
guitarx: replace the 100k resistor with 47k. Replace the 220k resistor with 100k.
Beautiful cleans :)
To fellow Valvecaster experimenters -- I've currently got this circuit on a breadboard, switching out everything and I have some items of interest to report, especially for those looking for more gain.
The nicest clean sound I've found so far, is with the following mods:
R2 = 100k
R3 = 47k
C1 = 0.1uf
Remove C4 and VR2
These changes gave a more honest clean sound than the original -- less distortion, better bass response and still adding the tube's character without too much change to the original clean tone. Increasing the gain brings in a light breakup that I really dig.
The nicest high gain sound I've found is from adding clipping diodes to the above mods. Two 1N34a Ge diodes with two 1N4148 Si diodes. I'm too much of a n00b to know the naming for clipping setups, so I'll just draw it in ASCii art :D
OUT Ground
| |
|---->|----| Ge
|----|<----| Ge
| |
|---->|----| Si
|----|<----| Si
I tried a heap of different combos of those two diodes in symmetrical and asymmetrical configurations, the above setup sounded the best so far. I still have some other Si types, schotkies(spl?) and MOSFET clipping arrangements I want to try.
Introducing the Ge diodes caused a big drop in output volume, so I've added a JFET gain stage before the output, which bought the volume up to being even with the clean version.
Tonight I will be experimenting with tone stacks -- a SWTC for the clean side and a big muff-based tone with switchable mid cut for the high gain version.
My plan for all of this is a pedal to put between my OD/dist/fuzz pedals and my modulation/delay pedals. The valvecaster responds really well to too much signal from pedals before it, so I've been using it as a dirty limiter of sorts. There will be two stomp switches -- an A/B for clean/high gain and a bypass switch. Each channel has it's own gain, tone and volume controls, with different tone stacks. All sharing the one tube, and all fitting in a BB enclosure. I've already laid it out and it'll fit nicely, I just have to decide on component values to get the sound I'm looking for. I envisage this staying on all the time in clean mode, then being switched to dirty mode to provide a second channel for single channel amps. Currently I use a catalinbread hyperpak for this, but this pedal is well on it's way to achieving a better sound.
All just my uneducated opinion, based on my gear, of course ;)
EDIT: all of the above is with a 12v power supply
Andrew, you are great!!! I want to experiment more on the Valvy, I already made the vero version I developed with sockets for R1 and R2, and ordered the other bits I was missing...With some different values GAIN pot...
I'll report my results...Please tell me more about the high gain channel, or how to obtain its highest gain...
It would be great to develop a kind of table with different uses (low gain, clean boost, high gain, ecc) and with sound samples...
Adriano - thanks, it was for you that I posted about high gain; I know we've both been chasing that since seeing this circuit :icon_twisted:
I'll report back when I've played with other clipping options some more, but to my ears the distortion is much more usable when generated by diode clipping and a gain recorvery stage rather than swapping resistors in the circuit.
Swapping out C1 for something larger helps add some more of that "chug chug" high gain -- but this circuit doesn't do the modern metal sound. I'm currently using 0.1uF, but tried up to 1.5uF film cap. It got too mushy with the 1.5uF.
I'd like to thank Jared for the gift...I received several tubes for free...That leaves me speechless...
Needless to say I tried them all...
Here's my thoughts on using them on Valvy running at 12V
* 12AU7 = the main choice, good. The one I liked the most was a RCA.
* 12AT7 = not bad, try one and see if you like the result...They sound good stock and I believe they could be even better with minor tweakings...
* 12BH7 = Didn't know that kind of tube...They are great to use on this project!!! They give a little more gain too, to my ears...
More on that later, my friends...
man i built one of these and i just cant seem to get it to work, anybody think they have an idea of whats wrong? ???
http://www.diystompboxes.com/smfforum/index.php?topic=66252.0
Quote from: cyberk007 on March 21, 2008, 02:52:04 PM
man i built one of these and i just cant seem to get it to work, anybody think they have an idea of whats wrong? ???
http://www.diystompboxes.com/smfforum/index.php?topic=66252.0
confused as to why you would post in this thread about another thread about an unrelated post, that has already been answered ???
I built one recently as well, and I really dig it.
It has a ton of hum, however, no matter the gain or volume setting.
Also, it seems to generate a noticeable octave effect, kinda like an octave-fuzz. More prominent on the higher frets and with the neck pickup.
Could this be a funky tube? I used a new JJ 12au7.
It's probably something I did wrong, but when working with tubes there is always a chance that it's the tube. :D
Quote from: culturejam on March 25, 2008, 09:00:30 PM
It has a ton of hum, however, no matter the gain or volume setting.
It's definitely your build/tube, not the circuit.
Here's a sample of mine, same passage played twice -- first time bypassed, second time with gain on zero and volume at unity. There's almost no noticeable difference in sound (just as I wanted ;))
clean valvecaster sample (http://notinteractive.com/stuff/guitar/fx/t00b/clean.mp3) signal path is carvin fatboy > valvecaster > roland microcube > mbox 2 (line in)
Mostly, hum = grounding issues. Check that the signal isn't "floating", with no reference to ground, at some point.
Quote from: andrew_k on March 25, 2008, 09:10:29 PM
It's definitely your build/tube, not the circuit.
Since nobody else mentioned hum, I figured it wasn't the circuit.
Quote from: brett on March 26, 2008, 06:01:36 AM
Check that the signal isn't "floating", with no reference to ground, at some point.
Will do. Thanks.
Quote from: culturejam on March 26, 2008, 02:22:05 PM
Quote from: andrew_k on March 25, 2008, 09:10:29 PM
It's definitely your build/tube, not the circuit.
Since nobody else mentioned hum, I figured it wasn't the circuit.
Quote from: brett on March 26, 2008, 06:01:36 AM
Check that the signal isn't "floating", with no reference to ground, at some point.
Will do. Thanks.
It could be your power supply. I used a small Boss 9V and got a lot of hum then changed to the bigger Boss PS (red one) and hum was gone. I'm trying to build a filter ckt but the cheaper / smaller transformer still produces hum. The bigger (red) Boss supply still runs this pedal clean.
I definitely agree with you, my Valvy has this horrible hiss, I only have unreguated PS. I gave it to my GF brother to try it, he had no hiss at all, using REGULATED PS. So I am waiting to receive those 7812s to filter the power...It seems a must, try it, after all it's just a little mod that seems to be so useful, reading others experiences in the ast pages...
LM317's and this circuit will remove your hiss http://www.dxing.info/equipment/wall_warts_bryant.dx . Thats what i use and mine is dead quiet.
Finally received that 7812 - mounted with the 100uF filter cap on the dc jack - hiss is just a memory... 8)
Now I really enjoy my Valvy!!!
Glad you got the problems resolved! :D
Did you place the 100uF across the +/- of the power leads?
I used the C1, C2, D2 from this power filter and still get the 60 Hz hum from my small wall wart.
(http://i215.photobucket.com/albums/cc70/tr-stompboxes/psu.gif)
Maybe there's a better filter out there. Any other recommendations?
Quote from: tranceracer on March 29, 2008, 12:31:51 AM
I used the C1, C2, D2 from this power filter and still get the 60 Hz hum from my small wall wart.
(http://i215.photobucket.com/albums/cc70/tr-stompboxes/psu.gif)
Maybe there's a better filter out there. Any other recommendations?
http://www.dxing.info/equipment/wall_warts_bryant.dx
Quote from: tranceracer on March 29, 2008, 12:31:51 AM
Glad you got the problems resolved! :D
Did you place the 100uF across the +/- of the power leads?
Yes, man, that was recomended some pages ago...
put a 100uF cap across the DC jack (positive leg to positive rail, neg. leg to neg. rail), then, instead of connecting the positive rail directly to the circuit, connect it to the regulator's pin1, ground to pin2, and the circuit to pin3. Then screw it on the enclosure. It is a 7812.The caps legs are soldered directly to the dc jack lugs...
Thanks Renegadrian, I'm going to try Forsakenrider's link using the 470uF and .1uF filter next.
Well here's my little contribution to this awesome thread. :D
Here's a smaller PC board for this cool little pre. I've used it and verified that it works. Haven't hooked up the voltage divider section but it should work too.
The trace and components are exactly mirrored so, fold on the line and iron the trace and components on the PC at the same time.
This is 300dpi image.
(http://i215.photobucket.com/albums/cc70/tr-stompboxes/MatsumiTubeVertPinsTrace.jpg)
(http://i215.photobucket.com/albums/cc70/tr-stompboxes/MatsumiTubeVertPinsTraceDetail.jpg)
Enjoy!!
Quote from: Renegadrian on March 20, 2008, 12:15:39 PM
* 12AU7 = the main choice, good. The one I liked the most was a RCA.
* 12AT7 = not bad, try one and see if you like the result...They sound good stock and I believe they could be even better with minor tweakings...
* 12BH7 = Didn't know that kind of tube...They are great to use on this project!!! They give a little more gain too, to my ears...
After the insertion of the 7812 in the circuit, which makes it very silent (Hell, dead silent!!! :icon_eek:), I tried again 12BH7 - well, they hum...Maybe they'd work with some tweaking, but not this way...6BQ7A seem to act the same way (and they do light a lot!!!).
Waitin' my breadboard to arrive, I believe those two types can give a lot more...
Got my Valvy 002 completed, up and running...I used...
- my Vero layout <---(insert PROUD smiley here...)
- 2.7M for R1 instead of 1M
- 470k for R2 instead of 220k
- 7812 and 100uF DC filter
- NO tone
It seems to have some more gain...Not a high gain box, but worth this lil' change...
Here's a pic...
(http://img230.imageshack.us/img230/3972/valvecaster0020304cs7.th.jpg) (http://img230.imageshack.us/my.php?image=valvecaster0020304cs7.jpg)
Guess who inspired me in this second version?! :icon_wink:
Nice work, love that sparkle paint!
I'm not surprised you've left out the tone control, I have grown to hate it :( I just leave it at full all the time so it doesn't suck treble. Next mods for mine are adding an output buffer and finding a replacement for the tone control. Maybe Jack's variation of the SWTC will do the trick.
Glad you liked it, Andrew! :icon_wink:
Yeah, I went toneless for this second Valvy - my first Valvy still has the tone control, I think it is not so useful...Maybe I'll put a on/off switch for a fixed rate booster (mosfet maybe, or Stratoblaster) so with a trimmer instead of the pot that controls gain...Or just a resistor...
That shoud go AFTER the tube, in my lil' experience...
Now it's time to go TWIN!!! 8)
Quote from: Renegadrian on April 03, 2008, 09:26:52 PM
That shoud go AFTER the tube, in my lil' experience...
I still disagree :P :P :P
I'm currently playing with a greedtone OD/dist absoluytely cranked, running into the valvecaster with gain on about 3.
Holy crap. Seriously heavy!
How do I add this regulator?
man, you should read some previous post,in this very same page... :icon_wink:
put a 100uF cap across the DC jack (positive leg to positive rail, neg. leg to neg. rail), then, instead of connecting the positive rail directly to the circuit, connect it to the regulator's pin1, ground to pin2, and the circuit to pin3. Then screw it on the enclosure. It is a 7812.
Quote from: andrew_k on April 03, 2008, 09:48:19 PM
Quote from: Renegadrian on April 03, 2008, 09:26:52 PM
That shoud go AFTER the tube, in my lil' experience...
I still disagree :P :P :P
I'm currently playing with a greedtone OD/dist absoluytely cranked, running into the valvecaster with gain on about 3.
Holy crap. Seriously heavy!
Well, I tried a Mosfet booster before and after...While the first solution overloads the tube, and the sound is just too "boomy", the second option boost the already distorted sound, leaving the tube to work at its best.
That in my lil' personal experience...Maybe the greedtone you have sounds best the way you use it... :icon_wink:
And now...I started to put the components in the vero for the Twinny...Got everything to hook up but the pots...damn...
Hey folks! I don't see the point of running 12AX7's at low voltage when space charge tubes were designed for that purpose and sound freakin' great while they're at it. Run a few of these in series and you can get anything from buffer to boost to overdrive. See ya!
(http://i137.photobucket.com/albums/q205/styrowfoam/the-huffer.gif)
Hey Brad, that seems so interesting...Does it work well??? Gotta add it to the "gotta build it soon" list... :icon_wink:
http://www.matsumin.net/diy/jisaku2/Valve_Caster/index.html
I'd really love to say ARIGATO to this man...Tht's the original page...Again, thx to Dano for his rendition...
I just ordered a 6111, and am thinking of powering a Subcaster from two 9v batteries in series - anyone know what difference this will make to the sound and any changes I may have to make to the circuit?
Tranceracer: That's a very nice layout. Thanks for sharing.
Everyone: I made a valvecaster for a guy, and he complained about getting in russian radio (those radiowaves really travel far) when using it with certain amps (but not his Boogie). Not that russian radio is such a bad thing, but it's not cool when combined with guitars... Is this an example of microphonics or is it something else ? Should there be some sort of RF filtering in this circuit to prevent this kind of thing happening, or would putting the tube INSIDE the box make all the difference ?
Put a sheild on the 12AU7.
Done that of course. Doesn't help.
Quote from: Krinor on April 06, 2008, 03:08:50 PM
Tranceracer: That's a very nice layout. Thanks for sharing.
No problemo my pleasure! :D
Quote from: Krinor on April 06, 2008, 03:08:50 PM
getting in russian radio (those radiowaves really travel far) when using it with certain amps (but not his Boogie). Not that russian radio is such a bad thing, but it's not cool when combined with guitars... Is this an example of microphonics or is it something else ? Should there be some sort of RF filtering in this circuit to prevent this kind of thing happening, or would putting the tube INSIDE the box make all the difference ?
Does the radio interference still happen when the box is bypassed?
Does it still happen when you turn the box 90 degrees?
Hey Kristian, you made a regen, didn't ya?! :icon_lol:
Just a thought - can anyone think of a 12V tube preamp (space charge tubes, maybe?) that will be clean enough to be used as a microphone preamp?
I haven't changed the Valvy components to go cleaner...Others reported it can be a good clean booster with those changes...
Otherwise, maybe the huffer (see previous page) could do the job, but again I don't know personally...
Got Valvy-addicted...I just can't stop playing thru this nice lil' box...
My fav tunes (the one this box fit well to my ears) are Whole lotta Rosie, Perfect Strangers, Demon's Eye, Black Dog, Hair of the Dog, Stargazer, Say what you will, Ready an' Willing, Gypsy Road...And the list could go on...
Quote from: frequencycentral on April 06, 2008, 02:43:27 PM
I just ordered a 6111, and am thinking of powering a Subcaster from two 9v batteries in series - anyone know what difference this will make to the sound and any changes I may have to make to the circuit?
Dear frequency. I personally love 6111's and have build many headphone amps and hifi equipement with them. Youre double 9 vold is good in one sense... the tubes love more voltage... but you will need to regulat the heaters to 6.3 volts. the tubes do not like more or less. Then by adding a regulator you will lose a lot of your power through heat, thus eating batteries for dinner.
Try a 24volt wall wart with a regulator for the heaters and youre rockin'.
Quote from: brad on April 04, 2008, 10:51:46 PM
Hey folks! I don't see the point of running 12AX7's at low voltage when space charge tubes were designed for that purpose and sound freakin' great while they're at it. Run a few of these in series and you can get anything from buffer to boost to overdrive. See ya!
(http://i137.photobucket.com/albums/q205/styrowfoam/the-huffer.gif)
But where the heck can we find space charge tubes!! I tried looking, not too common on the 'Bay
Quote
But where the heck can we find space charge tubes!! I tried looking, not too common on the 'Bay
http://www.tubesandmore.com/ (http://www.tubesandmore.com/)
forsakenrider - i would love to see more schematics using the 6111 - particularly hifi - do you have any? Thanks
Quote from: Fender56 on April 08, 2008, 03:06:19 PM
Quote
But where the heck can we find space charge tubes!! I tried looking, not too common on the 'Bay
http://www.tubesandmore.com/ (http://www.tubesandmore.com/)
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&rd=1&item=160227370765
Yes, maybe they aren't easy to find like the ol' 12A*7 family, but hey just browse a little... :icon_wink:
I think the spirit of this li'l project is to use a tube that's relatively easy to find and works well in this application. I was able to go down to my local guitar shop and pick up two 12AU7 on my way home from work.
I guess the next step is to move into more esoteric stuff to find that magic tone eh? :D
Yes, the TUBE ALCHEMY! :icon_biggrin:
A couple of quick questions...
1) Should the 1uf capacitors negative leg be leading into the circuit or into the tone pot in the Beavis schematic?
(http://www.beavisaudio.com/Projects/ValveCaster/MatsuminValveCaster.gif)
2) Has anyone built and verified the original Matsumin valvecaster layouts? might be cool to have a PCB version of this too.
(http://chawk.files.wordpress.com/2008/04/trurl_pagecontent2.jpg)
(http://chawk.files.wordpress.com/2008/04/trurl_pagecontent-12.gif)
(http://chawk.files.wordpress.com/2008/04/trurl_pagecontent2.gif)
Thanks.
Matt
(http://www.faqs.org/docs/electric/DC/00301.png)
Matt, regarding your first question - I used a non polarized cap, it works great...
And, no I haven't tried the original Layout (not yet...)
Also I remember someone suggested the use of a SHO to fatten its sound some pages ago...I just built it one myself...
Well, my two Valvies seem to sound worse with something before/after them...Even if the SHO is quite good played alone, it just won't fit that well with the Valvy, even with the gain at its middle position...
Thanks for the responses guys...
Bummed though because I tried it both ways and with a non-electro and it still isn't working... back to the lab I guess.
Quote from: Chawk on April 11, 2008, 10:59:57 AM
Thanks for the responses guys...
Bummed though because I tried it both ways and with a non-electro and it still isn't working... back to the lab I guess.
Is your pinout of the tube correct?
Quote from: TELEFUNKON on April 11, 2008, 01:15:26 PM
Is your pinout of the tube correct?
That is a good question... I actually ended up using an ECC802 but from what I've read they are identical to the 12AU7. I'm using a valve socket and it really only fits in one way. I'm stymied. works fine in bypass mode. when engaged I hear noise and when the strings are touched it sounds like a ground issue. everything seems to be wired up ok. probably just a matter of going over everything again.
Quote from: Aren on April 07, 2008, 04:58:17 PM
Just a thought - can anyone think of a 12V tube preamp (space charge tubes, maybe?) that will be clean enough to be used as a microphone preamp?
If you build a Valve Caster and change R2 and R3 to 50k it would clean up nicely. That's with a 12au7 tube. The space charge 12u7 has a bit less drive and would be a little cleaner than that.
TopView/BottomView... (http://www.diystompboxes.com/smfforum/index.php?topic=35105.msg284887#msg284887)
Quote from: Chawk on April 11, 2008, 03:17:06 PM
Quote from: TELEFUNKON on April 11, 2008, 01:15:26 PM
Is your pinout of the tube correct?
That is a good question... I actually ended up using an ECC802 but from what I've read they are identical to the 12AU7. I'm using a valve socket and it really only fits in one way. I'm stymied. works fine in bypass mode. when engaged I hear noise and when the strings are touched it sounds like a ground issue. everything seems to be wired up ok. probably just a matter of going over everything again.
Matt, I believe that is a typo, you meant ECC82. you know us and europe have 2 different way to mark tubes, so an ECC82 IS a 12AU7.
If you got a lil' piece of vero around, I'd suggest to go with that PERFECT layout (guess who drew it?! 8)) that I personally used and is tested, verified and guaranteed...
http://img361.imageshack.us/my.php?image=valvecasterv05sv9.jpg
http://img245.imageshack.us/my.php?image=valvecasternotoneog3.jpg
Else I'd have to come there and take a look (and my gf would be so happy, she lived there for some months and just love NYC, also our love story begins there, but I don't want to get you bored telling you all the story...)
http://www.eurotubes.com/euro-e.htm
Some info on tubes from some SUPER awesome guys.
they only sell JJ tubes but matt is right, the EC802 is a 12au7 or ECC82 variant. But it should definitely work.
Any pics matt? maybe one of use with a working valvey can spot the issue? also, what are you using for power?
Tried a clean mod today - replace R2 with a 100k resistor and R3 with a 47K. It clean out nice, but not entirely. It works pretty nice on an acoustic guitar miced with an electret condenser microphone (battery powered), but the circuit itself is too noisy to get an actual usable result (hiss/buzz - maybe RF - that is very apparent when the signal is amplified enough to get a usable signal from the microphone, especially if I run an LA-light compressor after it). Any thoughts? Filter caps, maybe?
Quote from: Aren on April 07, 2008, 04:58:17 PM
Just a thought - can anyone think of a 12V tube preamp (space charge tubes, maybe?) that will be clean enough to be used as a microphone preamp?
A low voltage mic pre would be godsend, but to get the amplification/sig to noise ratio right, I suppose you can´t get around space charge tubes.
Don´t know if it´s a good idea, but I found this overdrive schematic running from 9 volts AC (upped to 48 volts, so it might double as phantom power as well).
It uses a (very cheep, around 2 bucks) low voltage pcf802 tube, it might be transformed in a mic pre by putting 2 in series and tinker with it ?
http://www.tubepower.de/german/main_de.html
http://www.tubepower.de/pictures/projects/RTD-1-Live-schematic.jpg
Quote from: forsakenrider on April 13, 2008, 10:24:03 AM
http://www.eurotubes.com/euro-e.htm
Some info on tubes from some SUPER awesome guys.
they only sell JJ tubes but matt is right, the EC802 is a 12au7 or ECC82 variant. But it should definitely work.
Any pics matt? maybe one of use with a working valvey can spot the issue? also, what are you using for power?
No pics yet... I finally got this thing up and running over the weekend (thanks to Adriano's vero layout). The tube I ended up using was a ECC82. I was attempting to make this for a combo pedal coupled with a Dist + but the two didn't seem to like working with each other to my ears. Combining the two lost a bit of what makes the Valvecaster so nice with the warm smooth overdrive. I seem to think that a good combo might be more along the fuzz side I'm gonna keep experimenting to see what sounds the best. Thanks for everyone's help in getting this running! I'll let you know what I come up with.
Matt
Quote from: Chawk on April 14, 2008, 10:30:40 AM
No pics yet... I finally got this thing up and running over the weekend (thanks to Adriano's vero layout).
Matt
Happy it worked out right, I told ya!!! :icon_wink:
Hi!
I'm about to start building this awesome proyect, and want to ask a few questions to assure myself that i'm not going to waste any 12ax7 or other precious tubes in it :P. I readed the entire post about a hundred times and couldn't figure out what is the best voltage / tube config. I understad that when effect is used at 9v the 12au7 is the best choice, but what is the best when powering at 12v? Do I need to change any component value to drive it at that particular voltage?
I was also thinking about the possibility to add a "clipping module" to the stock configuration. Let's say I put on the pcb various tipes of clipping diodes (leds, GE, Si and the like) and select them through a rotary switch. It would be possible? I though that I could add another small cheap tube configured as a clipping diode to make it a even more massive proyect. Could this be possible?
Thanks for anyone who could help me, I always have too much ideas but less knowledge to carry them on.
Sebastian
Sebastian, I built 2 of them - they are intended to work at 9V or 12V, I prefer the second. Some hiss remains from DC and a voltage regulator is a good solution to make it deadly silent. As for the valves, 12AU7 is the main choice while 12AT7s work good too. 12AX7s just sound boomy...Not a good choice at all.
Whichever voltage you'll use, you don't have to make any change in the components, just the voltage regulator (7812 for 12V or 7809 for 9V)
You may want to change some components that change a bit its sound, but again it's your choice, may you need a cleaner box or a good overdriven sound. Tone control - I got rid of it, found it not so useful...Again, you decide...
As for the clipping module, haven't tried it yet, so you can be the pioneer and report your experiments here!!! :icon_wink:
juancra: I've also built a couple and much prefer 12v. I was getting a lot of hum using old RCA 12AU7s at 9v, but even with a brand new JJ valve it sounds better at 12. I'm not using a voltage regulator as I get no noise from my power supply.
re clipping diodes, I have tried symmetrical and asymmetrical configurations using various Si diodes, Ge diodes, red/green/yellow LEDs and mosfets. None of them resulted in a more musical/pleasing sound than the standard valvecaster. I also tried adding a JFET gain stage before the clipping diodes and/or a mosfet boost after and found that while it managed to bring the clipped signal up to the same volume as the non clipped signal, it was mushy and a little noisy (especially on the breadboard!). Another thing I tried was an EHX Muff Fuzz between the tube and the tone stack.
All of these experiments were interesting, some more usable than others, but all made "just another distortion" that to my ears was no better (and usually worse) than other distortion circuits that don't use a valve. All of the various experiments lost the mellow/warm drive that makes the valvecaster a fun circuit and either made it a mushy distortion or thin and crappy if smaller caps where used to reduce bass.
I don't want to discourage you from experimenting, just trying to pass on what I've already tried :)
Hi
Quoteeither made it a mushy distortion
you might find that it helps to lower the value of the grid-to-ground resistor. 220k to 470k are good values. 1M is probably too high. Higher values "store" super-low frequency charge on the grid.
cheers
Andrew and Adrian!
Thanks a lot for your quick response! I thought about adding the diode clipping to make this proyect more " interesting" to me 'cause it's the first serious proyect for my pedalboard and I wanted to have more "flavors" of it more than just a tone boost . With this new info I'm not sure if I will carry on with that mod, I think I'll just add a booster (don't know exactly which) before or after the effect and that will be all. About the hum issues Adrian found, I'll make a pcb that has the placements for the filtering portion. If it hums with my wall wart, i'll add what's necessary. Talking about tubes, I'm about to purchase a new Sovtek 12AU7, Is that a good tube brand?. How can I assure the tube is new?
Quote from: brett on April 14, 2008, 08:52:32 PM
you might find that it helps to lower the value of the grid-to-ground resistor. 220k to 470k are good values. 1M is probably too high.
Thanks for the tip Brett :) I probably should have mentioned that I had already replaced that resistor with a 470k ;)
juancra: There are sooo many bargain 12AU7s on eBay. No need to get new ones, the old ones are probably better. Just make sure they state in the auction that they've been tested and stick with a seller who sells a lot of tubes if you're uncertain.
I totally second what Andrew wrote... :icon_wink: I tried my Valvies with a SHO and with an AMZ Mosfet Booster, both before and after, and with my on board Stratoblaster. What they add to the sound is not that great for me, going from "uhm, okay" to "Hell, no!!!" :icon_evil:
Seb, about the hiss I wrote...I have non regulated wall warts, and that simple mod gave me a deadly silent circuit...just the 3 pin regulator and a electrolytic on the power jack...that's it!!! :icon_cool:
And as for the tubes, I went shopping on Evilbay :icon_twisted: this past week, I got 8 Sylvania for $32 shipped to Rome IT, it's like 2.50 Euros each...nuff said...
Also, I'd suggest you to try some different brands, each one I tried has its own character...
After all this talking you guys convinced me to go for the easy money and just build the valvy "as is". I will only add the filter section.
Regarding tubes, Here in south america we don't have Ebay, we have MercadoLibre, who has a "non-agression pact" with Ebay, but it is also a jungle.. Every time im about to buy something I think i'm going to get a plastic empty box :S .. :P, but I think i will go for a Toshiba 12AU7 for 10$ and pray for everything to go OK :D
Once again, I must say you guys at Diystompboxes rules!
I was wondering if it is necessary to let the preamp tube to warm-up before applying the plate voltage (even if it is around 12V) in order to extend their life? Or is it more a concern for power amp tubes, or tubes that run at "regular B+ voltages" (200V and +).
Saw this t-shirt on eBay - made me laugh! And no, its not my auction - I'm in the UK
http://cgi.ebay.co.uk/Rare-12AU7-Twin-Triode-Tube-T-Shirt-True-Geeks-Only_W0QQitemZ150234662850QQihZ005QQcategoryZ48710QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
I lost track after the first 8 pages but has anybody tried a tone stack instead of just a tone control? If so what were the results?
I imagine it wouldnt be all that great....probbly less gain/output.
In my little Valvy experiments, I removed the tone control...I just feel that the GREAT tone that comes out of the tube is well worth left unprocessed tonally speaking...
I was thinking of trying one of these:
http://www.tube-town.net/diy/tt-sam/tt-sam-sch01.JPG
..................specifically the tonestacks with the valvecaster (not the amp)!
Quote from: ItZaLLgOOd on April 15, 2008, 04:04:21 PM
I lost track after the first 8 pages but has anybody tried a tone stack instead of just a tone control? If so what were the results?
I tried a big muff tone stack. Not impressed. For me, this circuit needs midrange punch, and gets even more from removing the tone control entirely.
Quote from: Fender56 on April 15, 2008, 10:10:12 AM
I was wondering if it is necessary to let the preamp tube to warm-up before applying the plate voltage (even if it is around 12V) in order to extend their life? Or is it more a concern for power amp tubes, or tubes that run at "regular B+ voltages" (200V and +).
I'm not sure if pre warming tubes at this small voltage will extend the life that much but I did notice that as my 12AU7 pre warms up the overdrive tone actually gets less grit (which I like) and gets a little smoother. My GT 12AU7 seems pretty steady but some other tubes' character changes a little as they warm up.
I know it is a complete different circuit from the boosters I tried to couple with the Valvies, but I had to report that the 3dB gain of the Tillman Preamp are a nice add, it clears the sound a little too, and it doesn't get boomy at all, so let me suggest you this...
PUT A TILLMAN PREAMP BEFORE A VALVECASTER!!!
After all, it's just a simple circuit, so you can just try...But I believe it won't disappoint you...
Quote from: ItZaLLgOOd on April 15, 2008, 04:04:21 PM
I lost track after the first 8 pages but has anybody tried a tone stack instead of just a tone control? If so what were the results?
Try a Baxandall and a source follower. I haven't tried it, just a hunch.
Jered
The Baxandall has a lot of loss and will eat up quite a bit of signal.
First time i've ever tried a tube project.
I do have a ECC85 and in a bit unsure as if i should treat it as an replacement for the 12au7.
I've been looking at some data sheets and i found that the only diffrences are the heater current wich is a bit higher on the ECC85 and the absence of the center tapped heaters. Have i missed something or could i just pop it into this circuit?
http://www.radiomuseum.org/tubes/tube_ecc85.html
ECC type tubes are "cousins" of the american made 12a_7 family. You can use that one in this proyect.
From the http://www.nj7p.org/ site...
12AU7
Heater Voltage ................................ 6.3/12.6 V
Heater Current ................................ 0.3/0.15 A
ECC85
Heater Voltage ................................ 6.3 V
Heater Current ................................ 0.435 A
Also, ecc85 is missing the 9 pin heater connection...Also, thee heaters cannot work on 12V but only in 6V???
Anyway some ecc's stand in the 12a*7 yes, (in fact ecc82 is the equivalent for our 12AU7) but for what I read this ecc85 is not part of that family...Dunno if thie ecc85 can work in this circuit, but just try it out man...After all, if your first tube isn't the best, you can easily get a bunch of ol' 12AU7/ECC82 for so little $$ on ebay...
Sure thing, will do.
Just thought i'd ask in case i missed something. thanks for the replys.
Quote from: Ripdivot on April 17, 2008, 01:52:59 PM
The Baxandall has a lot of loss and will eat up quite a bit of signal.
Exactly, that's why you need the source follower.
Keep it simple. An N-chan JFET, 10k resistor, and a .1 output cap.
Jered
I tried building this although i got a problem.
My heaters run at full voltage (9.0 from pin 5 to 4).
I got pin 5 directly connected to R2 (220k) on the opposite side of pin 1 on the tube socket, is that the problem?
I skipped the tone controll and the only substitutions are a film cap for output cap and an ECC85 as tube (not put in when messuring voltages).
(http://i269.photobucket.com/albums/jj42/Albot1/222.jpg)
Albot, R2 is between pins 5 and 1 - that is correct...So the problem is somewhere else...Maybe the ECC85 we were arguing about...maybe you should stick to the tubes that are guaranteed to work (12AU7 and 12AT7) and experiment later on...
A silly question...Did you try to run it at 6V?
But am i supposed to read 9v between pin 4 and 5 with no tube in? I do.
I tried to start it up fist on 9 v and the tube lit up quite yellow quite like a light-bulb so i quickly turned it off and then accutlay tested it with 6v just to see if the heaters survived the light-bulb experience, it seems like they did
Didn't try to hook it up to an amp though.. maybe i should?
But am i supposed to read 9v between pin 4 and 5 with no tube in? I do.
ACTUALLY I REALLY DON'T KNOW...BUT YES, I BELIEVE...9V HAS AN ENTER AND AN EXIT POINT IN PINS 4 AND 5.
I tried to start it up fist on 9 v and the tube lit up quite yellow quite like a light-bulb
MAYBE THE CIRCUIT ISN'T GOOD FOR THAT TUBE, 12AU7s DON'T LIGHT THAT MUCH...
MY THOUGHT...VALVECASTER AND ECC85 AREN'T MADE TO BE TOGETHER...
You know.. i think it is something with the heaters.. when messuring the tube pins i get pretty much no resistance (3 OHM) is there more across the 12au7 heater pins??
even at 6 v the heaters start out at red then clinmb up to a very light yellow/orange and i hear the wallwart starting to sizzle (boiling caps?) so i think it pulls current like a madman!! no idea why though.
I'd better pick up a 12 au7 soon, would be nice to know if i should have 9v across pin 4 and 5 before trying it out though.
According to ECC85 datasheets, you must have 6.3V between pin 4 & 5, not 9V.
Hello from Geneva !
I build this tube boost last week and it work great ;D
(http://images3.hiboox.com/vignettes/1608/31yqv083.jpg) (http://www.hiboox.com/lang-fr/image.php?img=31yqv083.jpg)
The box is not finish...
I used a 12au7 from electroharmonix and 15v 500mA power supply regulated by a lm7812.
And I used the "pcb-less wiring diagram" from beavisaudio, there just one error, the Gain pot is wiring wrong ;)
A little sample with my es335 guitar, I'm not a good guitar player but this is only for fun :)
http://tflash.free.fr/12au7vavlecaster12v/MIC-2008-04-15_18h11m48s.wav (http://tflash.free.fr/12au7vavlecaster12v/MIC-2008-04-15_18h11m48s.wav)
Sorry for my English this is not my language...
I am trying a slight variation - single tube, 2 switches to go between clean boost and drive. I did the clean mod, changing R2 and R3 to lower values. I am putting a switch between pin three and the gain pot. Works fairly well so far. the clean boost in not a huge volume boost as is, but does fatten the sound and provide a decent boost. then kicking the gain in has been a nice addition.
I just picked up a box so I will post picks when I am done.
here is my post on the switch- probably going to a dpdt. Was trying to use a spare spdt, but can't use that and get an led going for the second switch
http://www.diystompboxes.com/smfforum/index.php?topic=67292.0
dav, without offense,for sure, but I surely have seen better fx... :icon_confused:
Also, you mean the error on the original layout was on the tone, wired the opposite pins...
For the record- I plugged an EC885 into mine and it works just fine.
I have built a clean 25W stereo power amp based on a tripath chip and I'm trying to decide on a preamp for it. I would like something warm, clean and tube-like that can be made to just break up a bit with high gain. I'm wondering if one of the many variations discussed in this (LONG!) thread would fit the bill. I'm trying to cram everything in to a small enclosure so the 6111 tubes really appeal to me. I would mount two in 8-pin DIP sockets on a single board with dual-gang pots to produce a stereo preamp. So.. given my requirement of a range of clean sounds to just breaking up "dirty" overdrive (a bluesy sound) does this seem feasable? I'm not sure if this circuit would produce enough gain to properly drive my power amp though.
Any thoughts?
Edit:
To give a better idea of what kind of tone I'm looking for my current "best choice" for a preamp is a Professor Tweed from ROG but a hybrid sounds much more appealing to me.
Also, if it helps to answer my question, the power amp I built has an input impedance of 22kOhms (but I can bump that up to 58K if I need more gain from the power amp) and is meant to be driven by a 1V RMS line level signal but can handle up to ~4V on the inputs before frying the chip.
Don`t over-heat this 12AU7 (http://www.newsensor.com/ProductHighLight.aspx?ProId=1264)!
Yes! My Valvecaster works! Just hooked it up - now I need to work on the enclosure. :icon_biggrin:
Now if I could just get my Subcaster to work......!
Tube-Town Pepper Shredder next I think! http://www.tube-town.net/diy/lov/lov02-peppershredder.html
quote author=frequencycentral
Yes! My Valvecaster works! Just hooked it up - now I need to work on the enclosure. :icon_biggrin:
GREAT! HAPPY TO READ THAT...ENJOY!!!
Now if I could just get my Subcaster to work......!
UH, DUNNO ABOUT THE SUBCASTER...CAN'T HELP...
Tube-Town Pepper Shredder next I think! http://www.tube-town.net/diy/lov/lov02-peppershredder.html
YES, SOMEONE POSTED A WHILE AGO...WOULD BE GREAT IF YOU OR SOMEONE ELSE COULD DRAW A P2P-PERF-VERO LAYOUT OUT OF THAT SCHEMATIC...
Thanks Renegadrian!
I built my Valvecaster on the tube socket - really easy. I don't think a perfboard is needed. I will build the Pepper Shredder the same way, its pretty much like two Valvecasters with a few mods.
I'll post some pictures tomorrow if I find time. I drilled the enclosure today - just need to fit it all in tomorrow.
Today I had fun:
LPB1 (DIY) > Valvecaster > Harley Benton GA5 (VJ clone) - Now that just rock!
then:
Valvecaster > Ruby > thru the GA5 speaker.
I'm defo going to build a combo with a Valvecaster, Ruby and 12" speaker - powered from a 9v battery!!
In fact I may even fit a Ruby in my Valvecaster enclosure and fit an extra socket for speaker out!
Quote from: frequencycentral on April 26, 2008, 05:43:28 PM
I'm defo going to build a combo with a Valvecaster, Ruby and 12" speaker - powered from a 9v battery!!
In fact I may even fit a Ruby in my Valvecaster enclosure and fit an extra socket for speaker out!
Nice idea !
How do you plan to wire the Valvecaster and Ruby together: will you keep the gain and volume pots on both of them ?
Quote from: nico13 on April 26, 2008, 05:59:32 PM
Quote from: frequencycentral on April 26, 2008, 05:43:28 PM
I'm defo going to build a combo with a Valvecaster, Ruby and 12" speaker - powered from a 9v battery!!
In fact I may even fit a Ruby in my Valvecaster enclosure and fit an extra socket for speaker out!
Nice idea !
How do you plan to wire the Valvecaster and Ruby together: will you keep the gain and volume pots on both of them ?
At the moment its just one into the other, so two gain controls, which is quite nice - with everything up full I get serious sustain - serious feedback too! I guess ideally I would want to be able to get a clean sound, so maybe the Ruby gain should be on a switched potentiometer.
Quote from: frequencycentral on April 26, 2008, 05:43:28 PM
I'm defo going to build a combo with a Valvecaster, Ruby and 12" speaker - powered from a 9v battery!!
That'll be great! ...for the 47 second life span of the battery ;)
Hahaha! maybe a car battery then, they're 12v - not so portable though! Unless - hmmm.........I could rig up a power feed from the car's cigarette ligher socket!
quote author=frequencycentral
I built my Valvecaster on the tube socket - really easy. I don't think a perfboard is needed. I will build the Pepper Shredder the same way, its pretty much like two Valvecasters with a few mods.
I KNOW RICK, I BUILT MY FIRST VALVY THE SAME WAY - I WAS ASKING FOR A LAYOUT OF THE PEPPER SHREDDER, I SAW THE SCHEMATIC BUT I AM NOT THAT EXPERT TO TRANSLATE IT TO A LAYOUT
still debugging mine :/
please take a glance at my picture and tell me if you find any errors.
I've been checkng it at least 10 times now and i think i'll go crazy sometime soon :icon_eek:
Does anyone have any thoughts on using this circuit as a preamp for my power amp?
-Matt
Quote from: Renegadrian on April 26, 2008, 08:36:51 PM
quote author=frequencycentral
I built my Valvecaster on the tube socket - really easy. I don't think a perfboard is needed. I will build the Pepper Shredder the same way, its pretty much like two Valvecasters with a few mods.
I KNOW RICK, I BUILT MY FIRST VALVY THE SAME WAY - I WAS ASKING FOR A LAYOUT OF THE PEPPER SHREDDER, I SAW THE SCHEMATIC BUT I AM NOT THAT EXPERT TO TRANSLATE IT TO A LAYOUT
Ok, I will post my layout based on mounting the component onto the sockets once its completed - give me a couple of weeks though!
Quote from: armstrom on April 26, 2008, 09:15:05 PM
Does anyone have any thoughts on using this circuit as a preamp for my power amp?
-Matt
I would think this circuit would make a perfect preamp for your power amp!
Quote from: frequencycentral on April 27, 2008, 07:37:30 AM
Quote from: Renegadrian on April 26, 2008, 08:36:51 PM
quote author=frequencycentral
I built my Valvecaster on the tube socket - really easy. I don't think a perfboard is needed. I will build the Pepper Shredder the same way, its pretty much like two Valvecasters with a few mods.
I KNOW RICK, I BUILT MY FIRST VALVY THE SAME WAY - I WAS ASKING FOR A LAYOUT OF THE PEPPER SHREDDER, I SAW THE SCHEMATIC BUT I AM NOT THAT EXPERT TO TRANSLATE IT TO A LAYOUT
Ok, I will post my layout based on mounting the component onto the sockets once its completed - give me a couple of weeks though!
that would be great, I wait to see it!!! Thank you Rick
Quote from: frequencycentral on April 27, 2008, 07:39:23 AM
Quote from: armstrom on April 26, 2008, 09:15:05 PM
Does anyone have any thoughts on using this circuit as a preamp for my power amp?
-Matt
I would think this circuit would make a perfect preamp for your power amp!
Thank you. I think I will give it a try. I'm building a tiny 25W stereo amp that runs entirely on 12V DC so this circuit will fit nicely. The entire thing (minus the power brick) fits neatly into a 6" x 3" x 2" enclosure. When I'm done I'll post some pics and hopefully some sound clips.
Here's another question though... If I were to build two of these preamp circuits (one for each channel on the power amp) would it make sense to use half of each tube in each of the channels to help maintain the same gain characteristics on each channel? I know some of the tube vendors will "match" tube pairs for a fee, but would this be a better solution?
For example, "Tube 1 side A" and "Tube 2 side A" would be used as the first and second gain stages for channel 1 while "Tube 1 Side B" and "Tube 2 Side B" would be used for the channel 2.
Am I simply making things more difficult for myself with no real gain? (no pun intended).
-Matt
Hi there,
I just finished a Pepper Shredder.
I used the 12U7 tubes, which are specially designed for 12 volt DC (in car radio's)
I like the sound of it very much.
It has a good amount of distortion.
I also placed a Fenderish Tonestack in the end before the volume.
Also some of the capacitors were changed for a "fatter" sound.
You have to use a good regulated power supply for this, otherwise you get a lot of hum.
To bad that I don't have time for a while to box it up. :icon_sad:
But anyway here are the layout and PCB for this project that I used.
If You use the PCB, scale it down to 56 percent.
I'm also planning to make a subcaster.........when I have the time for it :icon_frown:
(http://img229.imageshack.us/img229/920/6111peppershredderlayouah4.gif)
(http://img229.imageshack.us/img229/5783/peppershredderprintnr7.jpg)
(http://img74.imageshack.us/img74/3609/peppershredderju6.jpg)
Jimmy-H:
Well done and welcome! I would love to hear some sound clips of the Pepper Shredder if you have time. Have you tried it with 12au7's too?
Hi,
Have you tried it with 12au7's too?
No, but what I have read, the sound of the 12U7 is a little "fuller" compared to the 12au7.
The reason could be, that the 12U7 is made for low voltage.
.I would love to hear some sound clips of the Pepper Shredder if you have time.
Oke I'll try it, but I don't know how to post sound Clips.
A few photos of my Valvecaster - this one I built to drive my VJ clone harder so I didn't feel the need for a stomp switch, the enclosure is so small it wouldn't fit anyway.
(http://i210.photobucket.com/albums/bb292/frequencycentral/moto_0085.jpg)
Want to make your tubes glow brighter? I fixed a red LED in the centre of the tube socket.
(http://i210.photobucket.com/albums/bb292/frequencycentral/moto_0086.jpg)
Here it is!
(http://i210.photobucket.com/albums/bb292/frequencycentral/moto_0087.jpg)
And in low-light conditions:
(http://i210.photobucket.com/albums/bb292/frequencycentral/moto_0089.jpg)
Jimmy-H, your layout is so much appreciated, so thank you!!! Nice job!!! Wait for some more info (how much gainy is that fx?) and possibly some sound clips!!!
Rick, your valvy turned out great...I love that kinda finish...
I've been thinking a lot about the Valve Caster's two stages and where a two band EQ would work.
I applied the AMZ JFet buffer and Dual Tone control circuits and spliced them into the Valvecaster.
The Zed Caster has the buffer and tone circuit up front.
The Lab Caster has the buffer and tone in between the tube stages.
(http://www3.telus.net/public/david65/pedal-pics/valvecaster/ZedCaster.gif)
Never done this before. How do they look?
Are they both viable circuits still?
Which one would be most successful?
Dave
Hi
I think it would be safest to put a buffer (JFET makes sense) at the end, before the 100k volume pot. Otherwise, the impedance of the load might be too low for the seond valve stage.
cheers
Hi there,
The Pepper Shredder has plenty of gain.
An other idea is to leave the Tonestack, and then make a input cap selector (just like the Orange amps).
Then you have a more powerfull sound.
But I found some sound samples of the Vanilla Drive and the Pepper Shredder.
The Vanilla Drive is a little milder.
(According to the designer, the Vanilla drive can be used as a clean booster to a mild overdrive)
The tubes he used are 12AU7 from Electro Harmonics.
Here is the link : http://www.tube-town.de/ttforum/index.php?topic=7797.0
Only it's in German, but what the hack, so is the design
The Layout I posted has dissapeared, strange.
But here is it again:
(http://img233.imageshack.us/img233/1038/6111peppershredderlayoutc2.gif)
Ok, having built my Valvecaster I am now completely obsessed with vavle FX. I woke up this morning with the idea of an all tube multi-FX board going round my head. I think it would include:
1. a Valvecaster
2. part of The Tone God's tube tremolo
3. tube reverb (should be easy to adapt the VC to do this)
4. a tube based phaser - not sure if this one is possible???
Imagine: 4 stompswitches, half a dozen or more valves..........ooh! Any thoughts or ideas?
JimmyH, I read more on that forum...Some babel translation and it's more readable!!!
The pepper sounds good!!! Gotta build this one...
Quote from: frequencycentral on April 26, 2008, 05:43:28 PM
I'm defo going to build a combo with a Valvecaster, Ruby and 12" speaker - powered from a 9v battery!!
your not going to power both of them with one 9v battery? cause that wont do very well
OT
Andrew, is the guitar on your avatar one of yours? Are you left handed?
Quote from: Renegadrian on April 28, 2008, 06:30:36 PM
OT
Andrew, is the guitar on your avatar one of yours? Are you left handed?
Yes and yes -- it's a Carvin Fatboy (https://www.carvinguitars.com/carvinworld/catalog/guitars/index.php?model=hf2), but with a walnut neck and mahoganhy+quilted maple body. Highly recommended ;)
Hey I'm a southpaw too!!! :icon_surprised:
Quote from: frequencycentral on April 28, 2008, 05:31:46 AM
4. a tube based phaser - not sure if this one is possible???
Anything is possible. But keep in mind that a phaser incorporates 5 ic's (Small Stone). Each of them includes 11 transistors and 6 diodes. Now imagine doing what that little CA3080 does, only with tubes - times 5. A tube phaser would be fabulous though. Maybe there is another way ? :icon_wink:
I just uploaded a pdf file of a tube preamp, you can find it HERE (http://www.aronnelson.com/gallery/main.php/v/diyuser/6418+Tube+Preamp.pdf.html)
It's a very little and easy circuit and the 6418 is so easy to find and cheap.
Didn't build it yet, but hey it's so simple...I'll report it soon, I believe...
QuoteI just uploaded a pdf file of a tube preamp, you can find it HERE
It's a very little and easy circuit and the 6418 is so easy to find and cheap.
Didn't build it yet, but hey it's so simple...I'll report it soon, I believe...
Pentode preamp at low-voltage? COOOOOOOOOL!!!!!!!!!!! :icon_biggrin:
Hope it will be able to recreate the famous EF86 sound! (without the microphonics... ;))
Valvecaster sounds really good for me. Builded it yesterday with IC 7812 and ECC 82.
Sample here (http://"www.felicienne.com/extra/valvecaster.wma") : Tele -> valvecaster -> emu 0202 soundcard -> cubase.
Karsten
here is the dual subcaster that I've breadboarded...I'll get it in an enclosure soon, I really like it
(http://farm3.static.flickr.com/2119/2452066305_eb41f76e0a.jpg)
Quote from: Berger on April 29, 2008, 03:59:49 PM
here is the dual subcaster that I've breadboarded...I'll get it in an enclosure soon, I really like it
(http://farm3.static.flickr.com/2119/2452066305_eb41f76e0a.jpg)
Ahh....sweet glowing tubes.
Man, this thread has become a monster!
So I take it a single 6.3V power supply board (per the schematic) is sufficient to drive both heaters? I plan to use two tubes, but in a stereo configuration as my preamp stage. I bought both the 12AU7 tubes as well as the 6111's to see if there's any serious difference in gain. The 6111's will fit much better in the enclosure I plan to use, so that's what I'll build first.
-Matt
Yup Dano this thread has taken off, its got me going crazy buying tubes, even better is that I'm starting to understand this stuff, and am having a lot of fun.
The only thin I notices is suppling enough amperage to the circuit for it to work right. I was using a 12volt 300ma radio shack wallwart and would get flubby sounds out of it. I switched to a 700ma power supply for work and it sounds amazing.
Quote from: Berger on April 29, 2008, 06:01:20 PM
Yup Dano this thread has taken off, its got me going crazy buying tubes, even better is that I'm starting to understand this stuff, and am having a lot of fun.
The only thin I notices is suppling enough amperage to the circuit for it to work right. I was using a 12volt 300ma radio shack wallwart and would get flubby sounds out of it. I switched to a 700ma power supply for work and it sounds amazing.
http://www.nj7p.org/Tube4.php?tube=6111
Heater Current ................................ 0.3 A
According to this, you need 600mA only for the heaters, am I right???
Dano, this thread is killer...Apart form the the first ones, like me, Andrew and Kristian (krinor) I read more and more people interested in the Valvy...And the little effort in the building gives great satisfaction...You go like "WOW, i went TUBES!!!" 8)
Quote from: Renegadrian on April 29, 2008, 06:53:31 PM
http://www.nj7p.org/Tube4.php?tube=6111
Heater Current ................................ 0.3 A
According to this, you need 600mA only for the heaters, am I right???
Hmmm Renegadrian - maybe you just solved my Subcaster problem - not enough mA! I guess the 317 must consume some mA too - I will try a more powerful power supply.
Quote from: frequencycentral on April 29, 2008, 06:57:18 PM
Quote from: Renegadrian on April 29, 2008, 06:53:31 PM
http://www.nj7p.org/Tube4.php?tube=6111
Heater Current ................................ 0.3 A
According to this, you need 600mA only for the heaters, am I right???
Hmmm Renegadrian - maybe you just solved my Subcaster problem - not enough mA! I guess the 317 must consume some mA too - I will try a more powerful power supply.
Rick, if that's the case, glad I gave you a hint!!! :icon_wink:
Also a tip I ran a 220k resistor from the vin to pin 7 and that made a huge difference on my build as well
Quote from: frequencycentral on April 29, 2008, 06:57:18 PM
Quote from: Renegadrian on April 29, 2008, 06:53:31 PM
http://www.nj7p.org/Tube4.php?tube=6111
Heater Current ................................ 0.3 A
According to this, you need 600mA only for the heaters, am I right???
Hmmm Renegadrian - maybe you just solved my Subcaster problem - not enough mA! I guess the 317 must consume some mA too - I will try a more powerful power supply.
Hi there,
You don't neet the 317 with two tubes.
Just set the heaters of the two tubes in series, the current then is stil 0.3 A.
Right?
Hi Jimmy-H,
You need the LM317 of an IC 7812 to get a stable voltage on the heaters. Otherwhise you will shorten life of the tube(s).
I builded my Valvecaster with a wall wart 15V. and an IC7812, 100yF across the DC jack, pos.tip to pin 1 of the 7812, pin 2 to ground and pin 3 to the circuit.
Build the regulator on a heatsink.oh and connect only heater pins 4 and 5 of the tube.
Karsten
Quote from: iorr on April 30, 2008, 04:26:14 AM
Hi Jimmy-H,
You need the LM317 of an IC 7812 to get a stable voltage on the heaters. Otherwise you will shorten life of the tube(s).
I builded my Valvecaster with a wall wart 15V. and an IC7812, 100uF across the DC jack, pos.tip to pin 1 of the 7812, pin 2 to ground and pin 3 to the circuit.
Build the regulator on a heatsink.oh and connect only heater pins 4 and 5 of the tube.
Karsten
Yeah, your right about that ;)
But if u use good regulated powersupply in the first place, than you don't have to worry about that.
The only thing you have to do is remove the 47 E resistor in the supply filter of the subcaster.
Because of the low Resistance of the heaters.
Otherwise your voltage will drop
With tubes it's always important to have a good power supply to prevent hum.
I experienced that with the pepper shredder
yep, regulated power supply is very importent.
Builded this for my audio preamp - a little bit oversized - hahahahah
(http://www.felicienne.com/extra/netzteil01.jpg)
Karsten
Hello there
Sorry for a newbish question, but could anyone please tell me if i could use 6n1p russian 6v tubes for this project?
thanks
A quick glance at its details, and I believe this wouldn't be the best choice...
1) it runs on 6v, while the main tubes used here are 12v
2) it needs 600mA on heater
Quote from: Woodooman on April 30, 2008, 09:04:30 AM
Hello there
Sorry for a newbish question, but could anyone please tell me if i could use 6n1p russian 6v tubes for this project?
thanks
The 6N1P are pre-amp tubes but are generally used as a low-power tube in guitar amplifier (see www.ax84.com (http://www.ax84.com) for some examples), and requires about 250V on its plate (the heater is 6.3V). I don't know how it can behave in starved-mode, but it is not intended to (well, neither the 12AX7!). You can try it, but I doubt it will sound great.
Try it.
This one is similar to the 12AX7, ECC 88 or 6922. You can see them in a lot of high end audio applications. For the heater you will need a regulated 6.3V.
Karsten
Quote from: Jimmy-H on April 30, 2008, 05:41:35 AM
With tubes it's always important to have a good power supply to prevent hum.
I experienced that with the pepper shredder
Would a switching power supply be sufficient? I'm looking at this guy to power both my 25W stereo power amp and two Tubecaster preamps... http://www.mini-box.com/80w-AC-DC-Power-Adapter-12v-6-6A?sc=8&category=13
i won't bother if it will have a lot of hum.
-Matt
Quote
Would a switching power supply be sufficient? I'm looking at this guy to power both my 25W stereo power amp and two Tubecaster preamps... http://www.mini-box.com/80w-AC-DC-Power-Adapter-12v-6-6A?sc=8&category=13
i won't bother if it will have a lot of hum.
-Matt
In order to reduce the hum from your power supply, you should look for a low line regulation value (about +/- 1% will be great). Higher this value, higher the risk of hum.
In your case, this value is not shown so it is hard to predict. I assume it will be fine (those kind of big adaptors are usually well regulated) but ask for the return policy, just in case!
A switchmode power supply rather causes "whine" than "hum", IMHO...
Just been debugging my Subcaster - again.
I can't seem to unite the voltage regulator for the heater with the main circuit. I know the voltage regulator works fine without being connected to the main circuit.
So - I thought I'd try bypassing the voltage regulator and running the whole main circuit at 6 volts.
Result - it works. Distortion, but obviously no boost as the voltage is too low.
I drove it a little harder with my LPB-1 - excellent.
Conclusions: this circuit will work at 6 volt -with less gain.
As i can't seem to get the two parts together, I'm going to try this to get 6v for the heater from 12v:
(http://i210.photobucket.com/albums/bb292/frequencycentral/12v-6v.jpg)
The opamp can be anything really - 741, 1458, 351 etc
I've used it before to creat bipolar power for opamps and OTAs.
I will post my results.
Anyone care to comment?
Why so difficult?
Just place a 100yF acroos the DC jack. The pos. leg to pin 1 of an IC7812, pin 2 to ground, pin 3 to the circuit. If you want you can place another elco (47yf) on pin 3. So you get a regulated/cheapy and nice filtered power supply.
Karsten
Quote from: iorr on April 30, 2008, 03:47:38 PM
Why so difficult?
Just place a 100yF acroos the DC jack. The pos. leg to pin 1 of an IC7812, pin 2 to ground, pin 3 to the circuit. If you want you can place another elco (47yf) on pin 3. So you get a regulated/cheapy and nice filtered power supply.
Karsten
That would give 12 volts at pin 3, the Valvecaster (12au7) heater is 12 volt - but the Subcaster (6111) heater is 6 volt - well 6.3 volt to be exact.
This is a EF86 preamp running on 12-24 volts. Should be interesting.
http://www.tg-music.com/EF86.pdf (http://www.tg-music.com/EF86.pdf)
hi i just built the valvecaster
it seems the volume is a bit weak, it needs to be at around 3 o clock to maintain the bypass level.. is it all this way or just mine?
and i dont think the gain is enough, i used a 100k log pot besides the 50k, is it because of this?
and i feel its too bassy what mods can i apply to it?
i used a 12au7 tube running off 9v
no problem with noise
i used a booster pedal before it, and it sound great
but as a standalone.. i dont know..
can you guys pls suggest some modifications? thx!
Quote from: awitee on April 30, 2008, 07:01:16 PM
hi i just built the valvecaster
it seems the volume is a bit weak, it needs to be at around 3 o clock to maintain the bypass level.. is it all this way or just mine?
and i don't think the gain is enough, i used a 100k log pot besides the 50k, is it because of this?
and i feel its too bassy what mods can i apply to it?
i used a 12au7 tube running off 9v
no problem with noise
i used a booster pedal before it, and it sound great
but as a standalone.. i don't know..
can you guys pls suggest some modifications? thx!
Hi awitee,
You could try to run off 12 volt.(more headroom)
But you have to watch the heater voltage.
If you connect 12 volts to 4 and 5 of the tube, you will be alright.
With the bass thing....you can change the input cap.
I believe a smaller cap --> less bass.
Also, you can try to remove the tone-circuit or make it switchable(gives a little more gain).
success with your valvecaster!
Quote from: Jimmy-H on May 01, 2008, 05:25:07 AM
Quote from: awitee on April 30, 2008, 07:01:16 PM
hi i just built the valvecaster
it seems the volume is a bit weak, it needs to be at around 3 o clock to maintain the bypass level.. is it all this way or just mine?
and i don't think the gain is enough, i used a 100k log pot besides the 50k, is it because of this?
and i feel its too bassy what mods can i apply to it?
i used a 12au7 tube running off 9v
no problem with noise
i used a booster pedal before it, and it sound great
but as a standalone.. i don't know..
can you guys pls suggest some modifications? thx!
Hi awitee,
You could try to run off 12 volt.(more headroom)
But you have to watch the heater voltage.
If you connect 12 volts to 4 and 5 of the tube, you will be alright.
With the bass thing....you can change the input cap.
I believe a smaller cap --> less bass.
Also, you can try to remove the tone-circuit or make it switchable(gives a little more gain).
success with your valvecaster!
+1 on the 12V. Mine was barely more than unity gain with 9V. The input cap needs to be higher to brighten the pedal. I doubled mine and that works great! It is still "warm" sounding, but now you go from smooth dark tone to somewhat transparent eq with the toneknob. Try it, I really like mine now! I dont get overdrive without hitting it with a booster, but i also have low signal pickups on the relic strat i used it with. Have yet to try it with humbuckers. I think I will end up putting a booster in there with it just because i get GREAT sounds with my Tubescreamer set to minimum gain into the Valvecaster.
Quote from: Jimmy-H on May 01, 2008, 05:25:07 AM
Quote from: awitee on April 30, 2008, 07:01:16 PM
hi i just built the valvecaster
it seems the volume is a bit weak, it needs to be at around 3 o clock to maintain the bypass level.. is it all this way or just mine?
and i don't think the gain is enough, i used a 100k log pot besides the 50k, is it because of this?
and i feel its too bassy what mods can i apply to it?
i used a 12au7 tube running off 9v
no problem with noise
i used a booster pedal before it, and it sound great
but as a standalone.. i don't know..
can you guys pls suggest some modifications? thx!
Hi awitee,
You could try to run off 12 volt.(more headroom)
But you have to watch the heater voltage.
If you connect 12 volts to 4 and 5 of the tube, you will be alright.
With the bass thing....you can change the input cap.
I believe a smaller cap --> less bass.
Also, you can try to remove the tone-circuit or make it switchable(gives a little more gain).
success with your valvecaster!
mods i made was, i paralleled the 1M resistor with 690k to get a lower resistance for more gain
i also changed the input cap to .022microfarads to lessen the bass
and then i changed the gain pot back to the 50k B from 1M A
and also i now run it at 12V
results... OH YEAH hahaha
so happy with the result, great overdriven sound!! i couldnt be more happier
sounds super great when i drive it with either my queen may booster or ts808 clone
super great tone
im not sure what to do with the "But you have to watch the heater voltage." coz im not really experienced with tubes hehe this is my first tym
but it's still working so i guess im fine hehe thx alot for the help and instructions on this thread!
So, what is the expected gain of this circuit (at 12V) anyway? I'm planning to use this as a preamp for my power amp and I'm concerned that it may not provide enough gain to sufficiently drive the amp. I can adjust the gain of the power amp input stage but I'm not sure that will be enough if the gain from the preamp is too low. Keep in mind I'm not looking for crazy overdrive/distortion. This is going to be for blues so if the gain goes from clean to just starting to break up when cranked, it will be perfect. Of course, this assumes the distortion comes from the first stage overdriving the second, not both overdriving the power amp :)
Also, why would you reduce the input impedance if you're trying to get more gain? The lower the input impedance is the more input signal will be lost to ground. If anything, I would say to try 2M on the input resistor to increase the signal available to the first gain stage. Or am I missing something?
-Matt
Subcaster working!
All I did was remove C2, the 47nf cap across the supply rails and replace it with a different kinda 47nf cap. Weird. Hmmm, been bugging me for weeks!
So - I fired my Valvecaster into my Subcaster - WOW!!
It seems to me that the hassle of creating a 6.3 volt supply for the 6111 heater is a pain in the butt compared to powering a 12au7 heater at 12 volts. There really is no saving on space when you consider the extra circuitry required for the voltage regulator - and a heatsink on the LM317 too! There is a whole lot of heat generated by a 6111 in comparison to a 12au7. add that to the heat the LM317 gives out and you can warm the living room up nicely with a Subcaster!
My rule of thumb now will be to only use 6111's in pairs and run the heaters in series of 12 volts.
So - go ahead and build a Valvecaster. Or a dual Subcaster. Or a Pepper Shredder using two 6111's, like I'm doing next.
(Shit, I would do it this weekend but I have to write some music for Volvo!)
Just don't build a single 6111 Subcaster!
I had weak fizzy, farty tone with pathetic amount of gain with a $8.00 Yugoslavian tube.
Switched it with an $18.00 EH 12AU7 and I had plenty of gain and a nice over drive distortion.
After that...
I switched out the decoupling cap between stages to 0.0022uF to tune the bass where I like it with humbuckers.
Then I replaced the 1uf electro with a film cap.
I think it sounds great and I have plenty of gain. Yes a booster in front makes it sing!
Pics:
Top - link (http://www3.telus.net/david65/pedal-pics/valvecaster/vc-34-low.jpg)
Insides - link (http://www3.telus.net/david65/pedal-pics/valvecaster/vc-inside34.jpg)
Posted these in the pictures thread a while back.
Quote from: Pushtone on May 02, 2008, 03:09:34 PM
Pics:
Top - link (http://www3.telus.net/david65/pedal-pics/valvecaster/vc-34-low.jpg)
Insides - link (http://www3.telus.net/david65/pedal-pics/valvecaster/vc-inside34.jpg)
gorgeous dave! :icon_cool:
QuoteI had weak fizzy, farty tone with pathetic amount of gain with a $8.00 Yugoslavian tube.
Switched it with an $18.00 EH 12AU7 and I had plenty of gain and a nice over drive distortion.
These comments lead me to believe that you need a way of adjusting the bias for different make/models of tubes. Aron included a bias adjustment in his Shake Tube for this purpose. You might look at that for ideas or there may be suggestions earlier in this thread (I haven't read the whole thing). I suspect you could get this to work with a lot of different tubes (with correct pinout) if you had a way of adjusting the bias.
Hi all,
I encounter similar problems in using different brands of tubes within the 12au7. When I put a JJ (former Tesla) 12au7 into this circuit (valvecaster) there's hardly any output at all! I have similar problems with other designs on low voltages also (like a pedal I developed called the "ts-tube"). Sometimes a tube really puts out a great amount of output and tone and sometimes it's just plain dead! EH's seems to be most consistent in working within such designs, but not always...I think it has something to do with the way the heater can generate sufficient electrons for the cathode to be able to work...Anyone with similar experiences? What can be done to have this solved? I personally don't believe you can get away with this just by changing the bias point for the reason in cause I mentioned earlier: if there's not enough dissipation from the cathode, there isn't anything to begin with...
What are your opinions on this?
Like to know.
Have fun,
Ed's Custom Shop
Edwin Thoen
Maarssen
The Netherlands
www.edscustomshop.com
Well, I own so many 12au7s, so i tried them all, and while their tonal nuances are all slightly different, they all work great...
I got NOS GE, Raytheon, RCA ecc. and a new EH as well...
QuoteThese comments lead me to believe that you need a way of adjusting the bias for different make/models of tubes.
http://www.diystompboxes.com/smfforum/index.php?topic=63479.msg538894#msg538894 (http://www.diystompboxes.com/smfforum/index.php?topic=63479.msg538894#msg538894)
Hi there,
Just finished a Subcaster with a 6111 of GE.
The amount of gain for overdrive isn't that much.
But that I don't mind, because I want to use it for Boosting Solo's.
Therefore the Subcaster works great.
I'll place some pictures, as soon as I have boxed it in.
But that can take a while :'(
But I changed the input powersupply filter from Dano a littlebit.
Because when you use Dano's scheme, you loose at least 1.5 volt.
Just do the maths (current for heater is 300mA and R1= 47 oHm leads to roughly 1.5 volt loss)
So I moved/replaced R1 with a coil of 1mH.
I made a change in Dano's scheme, Hope you don't mind Dano! ::)
Otherwise I remove your drawing!! ;)
(http://img232.imageshack.us/img232/1990/subcasterfinalyb4.gif)
Quote from: Jimmy-H on May 07, 2008, 05:12:55 PM
But I changed the input powersupply filter from Dano a littlebit.
Because when you use Dano's scheme, you loose at least 1.5 volt.
Just do the maths (current for heater is 300mA and R1= 47 oHm leads to roughly 1.5 volt loss)
So I moved/replaced R1 with a coil of 1mH.
I removed both R1 and C2 From my Subcaster - it seems to work just fine.
Quote from: Jimmy-H on May 07, 2008, 05:12:55 PM
Just finished a Subcaster with a 6111 of GE.
The amount of gain for overdrive isn't that much.
I found my Subcaster gives similar gain to my Valvecaster. My 6111 is a French CSF tube, I have a Penta 12au7 in my Valvecaster. I do have some dodgy unbranded 12au7's, which give less gain and a softer sound - nice though. I have some Raytheon 6111's for my next build - so I'll see if they're different.
As someone said earlier in this thread - 'its all about the tubes!'
Quote from: Jimmy-H on May 07, 2008, 05:12:55 PM
Hi there,
Just finished a Subcaster with a 6111 of GE.
The amount of gain for overdrive isn't that much.
But that I don't mind, because I want to use it for Boosting Solo's.
Therefore the Subcaster works great.
I'll place some pictures, as soon as I have boxed it in.
But that can take a while :'(
But I changed the input powersupply filter from Dano a littlebit.
Because when you use Dano's scheme, you loose at least 1.5 volt.
Just do the maths (current for heater is 300mA and R1= 47 oHm leads to roughly 1.5 volt loss)
So I moved/replaced R1 with a coil of 1mH.
I made a change in Dano's scheme, Hope you don't mind Dano! ::)
Otherwise I remove your drawing!! ;)
One milly is better than no Henry at all,
but if this Dano "subcaster" (http://www.beavisaudio.com/Projects/ValveCaster/Subcaster.gif) schemo
is the one you compare yours (http://img232.imageshack.us/img232/1990/subcasterfinalyb4.gif) with,
check out where in Dano`s the heater current is running through (R1, and causing a drop...), going
where,
and
which current is running through L1 in yours,
and will that ever effect the heater?
:icon_wink:
Quote from: puretube on May 07, 2008, 07:05:43 PM
One milly is better than no Henry at all,
but if this Dano "subcaster" (http://www.beavisaudio.com/Projects/ValveCaster/Subcaster.gif) schemo
is the one you compare yours (http://img232.imageshack.us/img232/1990/subcasterfinalyb4.gif) with,
check out where in Dano`s the heater current is running through (R1, and causing a drop...), going where,
The voltage drop is on B+, wich you don't want.
The coil hardly gives a drop on B+.
But you can leave R1 (and L1) out when you use a good powersupply just what frequencycentral wrote.
Quote from: puretube on May 07, 2008, 07:05:43 PM
And which current is running through L1 in yours,
and will that ever effect the heater?
:icon_wink:
everything except for the heater current, causing hardly a voltage drop on B+
The heater current is going through the regulator so there will be hardly a Hum there.
Has anyone tried this circuit with a 12U7? They're designed to run with a plate and heater voltage of +12V. I'm wondering if they will produce any better results than using the 12AU7 which wants +100V or so on the plate.
Oh, and they're cheap...
-Matt
Quote from: armstrom on May 08, 2008, 01:55:26 PM
Has anyone tried this circuit with a 12U7? They're designed to run with a plate and heater voltage of +12V. I'm wondering if they will produce any better results than using the 12AU7 which wants +100V or so on the plate.
Oh, and they're cheap...
-Matt
This is a long thread.....but if you check back I'm pretty sure someone mentioned using a 12u7 and getting a softer sound with less gain.
How well does this work on line-level stuff? I'm looking to build something like this in stereo for synth use.
Hi there,
I finally had some time to box my pepper shredder in.
I called it the INDIAN TWIN TUBE DISTORTION>
Only the knobs are missing.
The box i used was an old printer switch (one printer more computers).
There were some holes in the lower part, that I had to close.
Put some tolex over it, and the holes were gone!
I also placed a 6-way switch for the input caps.
So here are some pictures :
(http://img514.imageshack.us/img514/7312/indianfrontgz4.jpg)
(http://img514.imageshack.us/img514/9083/indiangutshy0.jpg)
(http://img514.imageshack.us/img514/605/zijfc8.jpg)
I'm very pleased with the overall look.
Nice work...Want to listen to some clips!!! And maybe some detailed info about your pedal, the circuit, the components used, the PCB, etc...
Excellent work Jimmy H. I'm currently working on another Valvecaster with the tube mounted in a similar way to yours.
The Pepper Shredder is on my list - I'll use 6111's - i've been able to confirm that two 6111 heaters in parallel will run on 12 volts.
Which input caps do you have available by that switch - and can you describe the variations?
Quote from: Renegadrian on May 24, 2008, 08:52:13 PM
Nice work...Want to listen to some clips!!! And maybe some detailed info about your pedal, the circuit, the components used, the PCB, etc...
Hi Renegardian,
Thanks...
Most of it is discriped a few pages ago : http://www.diystompboxes.com/smfforum/index.php?topic=63479.420
PCB, layout (a page further) and the schemo of Tube Town.
The only things I added was a Fender-like tone stack.
(http://img236.imageshack.us/img236/8233/tswr6.jpg)
(http://img236.imageshack.us/img236/1126/tonestackum7.gif)
And the orange input selector:
(http://img236.imageshack.us/img236/3716/preamporangenw1.jpg)
These caps were soldered directly on the 6-way switch
It's prettymuch standerd stuff 0.5 watt resisters, filmcaps etc.
And not to forget 12U7 tubes.
Links to soundfiles were posted back then (only with more common 12au7 tubes).
It sounds very similar to mine.
Quote from: frequencycentral on May 24, 2008, 09:08:15 PM
Excellent work Jimmy H. I'm currently working on another Valvecaster with the tube mounted in a similar way to yours.
The Pepper Shredder is on my list - I'll use 6111's - I've been able to confirm that two 6111 heaters in parallel will run on 12 volts.
Which input caps do you have available by that switch - and can you describe the variations?
Thanks again frequencycentral ,
The switch is very usefull with different guitars.
It filters more or less bass-signals at the input.
I'm also thinking about to make the tonestack switchable.
And 12 volts for two 6111-tubes work great.
I'll like to hear from your 6111-pepper shredder!
Keep us posted!!!
thx for the reply jimmy!!! :icon_wink:
Quote from: Renegadrian on May 25, 2008, 02:52:20 PM
thx for the reply jimmy!!! :icon_wink:
You're welcome Renegardian :icon_wink:
Quote from: Jimmy-H on May 24, 2008, 05:57:56 PM
(http://img514.imageshack.us/img514/9083/indiangutshy0.jpg)
VERY nice job !!!!! :) The blue led idea is killing !
(May I take the opportunity of this post to ask if anybody know were I can get some tube socket adapted for 6111 tubes ? Thanks!)
[quote author=Darkness, Darkness link=topic=63479.msg544368#msg544368 date=121175034
(May I take the opportunity of this post to ask if anybody know were I can get some tube socket adapted for 6111 tubes ? Thanks!)
[/quote]
Hi Darkness,
I used a 8-pin ic-socket, just like Dano had written before.
This works very well.
Just cut the leads and bent it a little.
This is wat Dano wrote:
<edit: also found a potentially great way to mount those flying lead wires: use an 8-pin DIP socket as seen here: http://www.geocities.com/koalavilla/images/audio/pencil_pre_10.jpg >
Thank Jimmy-H ! Good idea, very clever I must say. I'll try this. Maybe just check for a model where I can be sure the tubes won't move (when moving the stombox for example)
Quote from: Darkness, Darkness on May 25, 2008, 05:46:53 PM
Maybe just check for a model where I can be sure the tubes won't move (when moving the stombox for example)
6111 tubes are designed to be soldered (or welded) directly to the board. You could try this. I did this with my Subcaster.
What about those...
http://www.scame.com/images/serie/mor001.jpg
or those used in audio amps...
http://www.quasarelectronics.com/images/3000/3047.jpg
The valve's wires could be hooked with one of the above, maybe...
I'm currently woking on a LPB-1/Valvecaster pedal and I've come up with a neat way to mount the tube inside the enclosure:
(http://i210.photobucket.com/albums/bb292/frequencycentral/moto_0220.jpg)
I considered all sorts of other ways: bolting the tube socket to the side of the enclosure, mounting it using a bent bit of metal etc.
This way works really well. I used fibreglass perf, which is really tough, and drilled/filed a hole big enough for the socket. The socket is actually soldered to the board after using wire to secure it in place. The resulting board JUST fits the enclosure. The pot/circuit to the left is the LPB, the pot to the right is the Valvecaster volume.
I'll be using two stomp switches - one to use the LPB to boost, the other to bypass both circuits.
Great pic, Rick...Just 2 Qs..
1) What kind and size of enclosure are you going to use?
2) LPB+Valvy=didn't try myself (but I'll do, as I have one LPB lying around...) - but IMO the Valvy is not treble screaming, and LPB is famous for being on the bass side...So how do they sound togheter? Aren't they too much on the bass side? Can this couple give some decent highs?
Quote from: frequencycentral on May 26, 2008, 06:56:17 AM
I'm currently woking on a LPB-1/Valvecaster pedal and I've come up with a neat way to mount the tube inside the enclosure:
(http://i210.photobucket.com/albums/bb292/frequencycentral/moto_0220.jpg)
I considered all sorts of other ways: bolting the tube socket to the side of the enclosure, mounting it using a bent bit of metal etc.
This way works really well. I used fibreglass perf, which is really tough, and drilled/filed a hole big enough for the socket. The socket is actually soldered to the board after using wire to secure it in place. The resulting board JUST fits the enclosure. The pot/circuit to the left is the LPB, the pot to the right is the Valvecaster volume.
I'll be using two stomp switches - one to use the LPB to boost, the other to bypass both circuits.
Hi frequencycentral
Looks good!
It's funny, because my Subcaster looks almost the same.
Eeeeh we are on the same frequency isn't it!!
Only I made a PCB.
In this way you have very few wires.
I drilled a whole under the IC socket for the 6111 tube.
To mount a led the same way as my Indian pedal.
I'll see if I can place a picture tonight!
But I still have to box it in......in time.....
Quote from: Renegadrian on May 26, 2008, 07:16:28 AM
Great pic, Rick...Just 2 Qs..
1) What kind and size of enclosure are you going to use?
2) LPB+Valvy=didn't try myself (but I'll do, as I have one LPB lying around...) - but IMO the Valvy is not treble screaming, and LPB is famous for being on the bass side...So how do they sound togheter? Aren't they too much on the bass side? Can this couple give some decent highs?
(http://i210.photobucket.com/albums/bb292/frequencycentral/moto_0221.jpg)
The enclosure is a Hammond (Eddystone) 3907 (120x95x30) - from my local Maplin: http://www.maplin.co.uk/module.aspx?ModuleNo=43713&doy=26m5
As for the sound - it's what your ears enjoy! You have a Valvy and an LPB-2 (same as the LPB-1, EH just put it in a different box) - hook them up! I've been using my other Valvy with my LPB and really enjoy it - maybe there's a place for 'dark' in my guitar sound and on my pedalboard! I have a range of fuzz/overdrive/distortion to choose from now (I'm also working on the fuzz section of the Colorsound Fuzzwah, using vintage BC107's), it's nice to vary it a bit.
Quote from: Jimmy-H on May 26, 2008, 08:22:07 AM
Hi frequencycentral
Looks good!
It's funny, because my Subcaster looks almost the same.
Only I made a PCB.
In this way you have very few wires.
I drilled a whole under the IC socket for the 6111 tube.
To mount a led the same way as my Indian pedal.
I'll see if I can place a picture tonight!
But I still have to box it in......in time.....
Thanks Jimmy. Great minds think alike......!
As for boxing stuff up - since I joined this forum my builds take longer - this is because you guys make some great looking pedals, and now it's not good enough for me to just get the electronics right - so I have to wait wait wait - for paint to dry, for decals to dry, for varnish to dry etc!
Quote from: frequencycentral on May 26, 2008, 08:30:13 AM
You have a Valvy and an LPB-2 (same as the LPB-1, EH just put it in a different box) - hook them up!
I did, Rick...But my ears tell me I personally don't like the Valvy with the LPB - it sounds muddy and "fuzzy" to my ears, and there is no shine at all...I did my test with my toneless Valvy and the LPB2 trying with 2N5088 and BC108.
I really love to put a Tillman in front of my Valvies, it adds a little push and some shine...So it sounds more "complete" to my ears...It adds some highs that the Valvy alone hasn't got...
But hey that's the beauty of tastes, both yours and mine are ok, as long as it sounds good to the ears!!! :icon_wink:
Isn't it?!?
Quote from: Renegadrian on May 26, 2008, 09:06:04 AM
I did my test with my toneless Valvy and the LPB2 trying with 2N5088 and BC108.
I have BC547 in mine - too much hfe???
Quote from: frequencycentral on May 26, 2008, 09:25:28 AM
Quote from: Renegadrian on May 26, 2008, 09:06:04 AM
I did my test with my toneless Valvy and the LPB2 trying with 2N5088 and BC108.
I have BC547 in mine - too much hfe???
Well, BC547 is supposed to be the ol' BC107 with more gain...
Anyway, I don't think it's a GAIN thing, but a tonal response of the circuit itself...
Too "bassy"...Not my cup of tea indeed...
Hi frequencycentral ,
Here it is my: 6111-Subcaster.
You can see some resemblance with your design.
My idea was also a simple way of mounting the whole thing with the pots.
(http://img213.imageshack.us/img213/3078/6111subcasterwo8.jpg)
Quote from: frequencycentral on May 26, 2008, 08:30:13 AM
As for boxing stuff up - since I joined this forum my builds take longer - this is because you guys make some great looking pedals, and now it's not good enough for me to just get the electronics right - so I have to wait wait wait - for paint to dry, for decals to dry, for varnish to dry etc!
There your totally right!!!!
Quote from: Darkness, Darkness on May 25, 2008, 05:46:53 PM
Thank Jimmy-H ! Good idea, very clever I must say. I'll try this. Maybe just check for a model where I can be sure the tubes won't move (when moving the stombox for example)
As you can see darkness, the tube is mounted in a IC-socket.
It is sturdy enough when you move the stompbox !
Quote from: Jimmy-H on May 26, 2008, 05:56:30 PM
Hi frequencycentral ,
Here it is my: 6111-Subcaster.
You can see some resemblance with your design.
My idea was also a simple way of mounting the whole thing with the pots.
(http://img213.imageshack.us/img213/3078/6111subcasterwo8.jpg)
Superb work Jimmy - it does look similar to mine! I tend to go for mounting the pots onto the circuit board whenever possible - cuts down off-board wiring and its an easy way to mount the board in the enclosure too! I did similar for my MXR Distortion+, which meant the board had to be only 18x8 holes - ultra compact - but also very pleasing. Also recently did an LPB for a friend this way, the board was 8x7 holes.
I love your blue LEDs too!
Quote from: frequencycentral on May 26, 2008, 10:00:00 PM
Superb work Jimmy - it does look similar to mine! I tend to go for mounting the pots onto the circuit board whenever possible - cuts down off-board wiring and its an easy way to mount the board in the enclosure too! I did similar for my MXR Distortion+, which meant the board had to be only 18x8 holes - ultra compact - but also very pleasing. Also recently did an LPB for a friend this way, the board was 8x7 holes.
Thanks Frequencycentral,
I also did a few boards that way, it's also a bit of a challenge to fit the components in such a small space.
Quote from: frequencycentral on May 26, 2008, 10:00:00 PM
I love your blue LEDs too!
Thanks again, a great way of feeling blue!
(http://img294.imageshack.us/img294/9443/290509xi6.th.jpg) (http://img294.imageshack.us/my.php?image=290509xi6.jpg)
Here is my third Valvy, I also posted it in the Pictures thread...
Again, it has some slight differences from the original circuit I layed out
(http://img245.imageshack.us/img245/3325/valvecasternotoneog3.th.jpg) (http://img245.imageshack.us/my.php?image=valvecasternotoneog3.jpg)
* I raised the R1 and R2 values - R1 = 2.2M | R2 = 390K
* This time I used a electr. cap for C3, as in the original Dano schem - a normal cap works too BTW
* I tried a bigger value for the GAIN pot - 250k - but it wasn't just right...I changed back to the original value...
* Again, NO useless tone control...And NO LED. Staight tube power.
Hello folks,
I just built my first Valvecaster, and it doesn't sound right, no where near as beautiful as the sound clips I've heard from other forum members. I was wondering if I should ask for help here or start a new thread?
Nick
Quote from: Renegadrian on May 29, 2008, 08:07:11 PM
(http://img294.imageshack.us/img294/9443/290509xi6.th.jpg) (http://img294.imageshack.us/my.php?image=290509xi6.jpg)
Here is my third Valvy, I also posted it in the Pictures thread..
Looks Great Adriano!!!!!
I also have seen them on the picture thread.
But some of my pictures have dissapeared (again) . :icon_evil:
Have some of you the same problem with ImageShack? ???
So I post my Indian Twin-Tube Distortion again:
(http://img46.imageshack.us/img46/518/indiangutsus4.jpg)
(http://img46.imageshack.us/img46/2258/indianfrontop9.jpg)
(http://img46.imageshack.us/img46/7039/zijds0.jpg)
Quote from: sengo on May 29, 2008, 09:44:26 PM
Hello folks,
I just built my first Valvecaster, and it doesn't sound right, no where near as beautiful as the sound clips I've heard from other forum members. I was wondering if I should ask for help here or start a new thread?
Nick
I believe that's the right place...
All right, first tell us how did you build this:
Did you use my vero layout, or Dano's point to point or...
Tone or toneless...
9v or 12v...
Is the sound coming out correctly in bypassed mode...
Did you change some components or kept the original list...
Did you double-triple check every connection...
Did you try with another tube and wall wart...
QuoteDid you use my vero layout, or Dano's point to point or...
Tone or toneless...
9v or 12v...
Is the sound coming out correctly in bypassed mode...
Did you change some components or kept the original list...
Did you double-triple check every connection...
Did you try with another tube and wall wart...
I used Dano's point to point layout, with no tone control and no volume control (I was just trying it out, so I did not spend the time to soldier up a volume pot). It's running at 9V, and I've tried both a wall wart and a 9V battery, they both sounded quite similar except the wall wart added noise. I used all the original components, and I checked them numerous times to make sure they were right, and right now it is wired up with no bypass switch (effect always on). It actually works alright, but it sounds very gated, buzzy, and weak, similar to a very mis biased fuzz face. When I boost the input signal I get much more overdrive (obviously), but its not very nice sounding, very buzzy.
I only have two 12AU7 tubes, and they are both EH, one is normal, and the other is "high gain". Could the tube brand make that much of an impact on the tone? After I already ordered the tubes I found out that many of the builders were displeased with EH tubes, but they didn't sound THIS bad did they?
sengo - check the battery voltage - my battery Valvecaster starts to sound bad once the battery goes down below 8 volts.
Nick, the wall wart noise is easily resolved with the voltage regulator you can read in this very same thread...
Basically its just a 100uF el. filter cap and a 7809 or 7812
Else, I dunno what to tell you...recheck the tube pins' number...
As for the tubes, I have one new EH 12AU7 bought from Banzai - No, they don't sound so bad, you can get better tubes, but the one I got sounds good, so it stays...So the tube is not to blame...
Different brands have different tone nuances, but they all work as long as they are the same type...
Maybe post some pics of your attempt...We can check it better...
EDIT - try it at 12v too.
Quote from: Jimmy-H on May 30, 2008, 02:18:56 AM
So I post my Indian Twin-Tube Distortion again:
I love that Indian logo. :icon_wink:
Nice work!!
Quote from: sengo on May 29, 2008, 09:44:26 PM
Hello folks,
I just built my first Valvecaster, and it doesn't sound right, no where near as beautiful as the sound clips I've heard from other forum members. I was wondering if I should ask for help here or start a new thread?
Nick
In addition to Renegadrian's suggestions, what kind of sound are you getting? If it's sputtering "farting" kind of sound maybe the ground wire to the jacks aren't connected (I had that happen when I was prototyping mine). Maybe a picture can help.
Builded the valvecaster. Great stompbox. No hum - a real quit one.
Gives me the Keith Richards sound.
Karsten
(http://www.felicienne.com/extra/valvecaster.jpg)
Quote from: iorr on May 30, 2008, 03:25:38 PM
Builded the valvecaster. Great stompbox. No hum - a real quit one.
Gives me the Keith Richards sound.
Karsten
(http://www.felicienne.com/extra/valvecaster.jpg)
Excellent build! The tube protector reminds me of the TubeTown Pepper Shredder!
The tube protector is brilliant.
A couple of standoffs and washers.
Love it.
Dave S.
Really nice build!!! :icon_wink:
yep,
Inspired by tube town ;D.
M24 steel washer.
Karsten
Quote from: DougH on May 30, 2008, 12:36:26 PM
I love that Indian logo. :icon_wink:
Nice work!!
Thanks DougH !
I also like it a lot.
Gives it a bit vintage look !
But strange, the lost pictures have returned again........strange Image Shack!!
Quote from: iorr on May 30, 2008, 05:54:10 PM
yep,
Inspired by tube town ;D.
M24 steel washer.
Karsten
Karsten a very clever solution ;) .
I've seen such a tube cage at Banzai. http://www.banzai-effects.de/Gold-tube-cage-pr-20588.html
But i found them to expensive.
The way you did it saves a lot of money :icon_smile: !!!
Again, a beautiful design...your box
Iorr, any chance of an interior "gut" shot pic?
Please!
Sure :icon_wink: Little bit of chaos in there....
(http://www.felicienne.com/extra/valveinside.jpg)
Karsten
Quote from: Jimmy-H on May 26, 2008, 05:56:30 PM
Quote from: Darkness, Darkness on May 25, 2008, 05:46:53 PM
Thank Jimmy-H ! Good idea, very clever I must say. I'll try this. Maybe just check for a model where I can be sure the tubes won't move (when moving the stombox for example)
As you can see darkness, the tube is mounted in a IC-socket.
It is sturdy enough when you move the stompbox !
Thanks !! I'll use this method for sure ! :) I have received the tubes but still waiting for the LM317 .... :(
Quote from: iorr on May 30, 2008, 03:25:38 PM
Builded the valvecaster. Great stompbox. No hum - a real quit one.
Gives me the Keith Richards sound.
Karsten
(http://www.felicienne.com/extra/valvecaster.jpg)
Really too cool looking !!!!! great job !
Iorr, thanks for the inside shot.
Quote from: tranceracer on May 30, 2008, 01:24:42 PM
Quote from: sengo on May 29, 2008, 09:44:26 PM
Hello folks,
I just built my first Valvecaster, and it doesn't sound right, no where near as beautiful as the sound clips I've heard from other forum members. I was wondering if I should ask for help here or start a new thread?
Nick
In addition to Renegadrian's suggestions, what kind of sound are you getting? If it's sputtering "farting" kind of sound maybe the ground wire to the jacks aren't connected (I had that happen when I was prototyping mine). Maybe a picture can help.
Why don't you post some sound clips ? It's probably easier to
hear what's wrong than to see it in this case - since the circuit is working. Try different tubes. I've had great success using 5751's on my last few builds.
I also tried some tubes labelled 5963 - they work.
but as you can read they're part of the same family.
http://www.nj7p.org/Tube4.php?tube=5963
All nine pin double triodes "work" in this circuit. 5751's are low to medium gain and like the mentioned 5963 is a very good substitute for something like a 12AU7. I also tried some NOS GE 12AV7's and they are okay, although IMO not as nice and creamy as the 5751.
Has anyone tried anything from JJ in this thing lately ?
Quote from: Krinor on June 01, 2008, 05:58:17 AM
Has anyone tried anything from JJ in this thing lately ?
Yes, JJ 12AU7. Compared to a RCA 5751 it was brighter, "brittle" would be a word to describe the difference. I think the JJ would be better for a live situation where the pedal was being used as a lead boost. The RCA sounds nicer when being hit by a boosted signal.
Already out this in the 'Pictures!' thread but what the hey!
Valvecaster with stompable LPB boost:
(http://i210.photobucket.com/albums/bb292/frequencycentral/moto_0258.jpg)
thanks for sharing, Rick!!!
I love to see other people's work, expecially on the Valvy...
Altough it's the same f***ing circuit wit the lowest components list, every pedal looks different from the others...
Hi Rick,
Sure looks great!!
The Tube is invisible, but well protected.
Very practical on the road.
Really nice build.
Looking forward to your next!
A hell of a thread you started here Dano! :D
And it seems not to end yet :icon_wink:
Quote from: Renegadrian on June 01, 2008, 02:58:40 PM
thanks for sharing, Rick!!!
I love to see other people's work, expecially on the Valvy...
Altough it's the same f***ing circuit wit the lowest components list, every pedal looks different from the others...
Thanks Adriano - yeah simple circuit - but it was wiring the two 3pdts that was the mindbender here. I made the bypass switch bypass both circuits, the boost switch just cuts out the LPB. Took a while to get my head around how to do that!
Quote from: Jimmy-H on June 01, 2008, 03:20:04 PM
Hi Rick,
Sure looks great!!
The Tube is invisible, but well protected.
Very practical on the road.
Really nice build.
Looking forward to your next!
A hell of a thread you started here Dano! :D
And it seems not to end yet :icon_wink:
Thanks Jimmy. Well protected - yes! My first VC was for home use - this one is for gigging with.
As for other builds - I finished three other enclosures yesterday, all the electronics done too - I just need to 'pot' them up - so it should be a bumper week for me in the 'Pictures!' thread.
And yes - one hell of a thread - its this thread and Dano's site which got me into the forum in the first place.
Thanks again Dano!
Rick
Hi Rick, question for you. I'm curious how hot your pedal gets with the LM317 and the tube inside the enclosure? I'm wondering if I need to drill vent holes before I paint.
Thanks, Jered
Quote from: Jered on June 01, 2008, 07:19:55 PM
Hi Rick, question for you. I'm curious how hot your pedal gets with the LM317 and the tube inside the enclosure? I'm wondering if I need to drill vent holes before I paint.
Thanks, Jered
Hi Jered,
There is no LM317 inside - this Valvecaster runs on 12 volts, including the heater.
Maybe its the Subcaster that you are thinking of that needs the LM317 for its 6.3 volt heater?
As for heat off the tube - I only finished the pedal today, so it hasn't been plugged in for long. I'll be using it at band practice on Wednesday so I'll report back. I did consider vents - I may still have to drill them!
My other Valvecaster is 9 volt battery powered - the tube gets warm but not hot. I don't know how much differance it will make being powered at 12 volts from a wallwart.
I can tell you this: I built a little amp recently, using a Subcaster as a preamp into a LM386 based amp, I'll be boxing it up this week. The 6111 submini tubes get much hotter than 12au7 tubes, and the LM317 does get seriously hot - even with a heatsink. The enclosure for this project is vented.
Rick
Thanks Rick, I wasn't sure what voltage you were running it at and needed the volt reg or not, that's why I asked. Please do post your results after your rehersal, I'll hold off on the vent holes until then.
Thanks, Jered
Hi again,
Sorry I have taken so long to respond about my Valvecaster.
I took some voltages, ans was wondering if anyone could compare theirs to mine? To me it just sounds really poorly biased. I also found out my 9V 500 mA power supply actually runs around 12.6 Volts when not plugged into the jack on my Valvecaster, it is an EH power supply. when the jack and take a reading across the positive terminal and ground I get a reading of 11.05 Volts, but I have gotten readings as low as 10.9V. Here are my voltages:
Pin 1: 7.63V
Pin 2: 0.00V
Pin 3: 0.72V
Pin 4: 0.00V
Pin 5: 10.99V
Pin 6: 4.46V
Pin 7: 0.37V
Pin 8: 0.00V
Pin 9: 5.52V
A lot of these voltages seem to fluctuate slightly while taking them. I don't know if that will help diagnose the problem. I'll try to get a picture up later perhaps, but I don't know how helpful that will be, right now my project sort of looks like an octopus.
Nick
A few weeks ago I reported that a brand new YUGO tube (12AU7) that I paid $8.00 for sounded terible in the Valvecaster. Farty, sputtery, week, no gain.
I swapped it for the EH tube thats been serving in my Firefly amp. Ah, tonal bliss with the Valvecaster and EH tube.
The Yugo tube got put in place of the EH in the Firefly amp where I could not tell the difference between tube. They sound the same in the Firefly.
Three weeks later the Yugo has about 6 - 8 hours of use in the firefly amp.
I pull it out of the amp and into the Valvecaster. Gee, it sounds very good now. WTF.
Did it get burned in from the high voltage in the Firefly? Why does it sound good now?
Before the difference between the Yugo and the EH has huge. Now there is a "just noticeable difference" between the two.
The EH is still better, but only slightly.
One side note to this history....
The Yugo flashes a bright white light from inside the tube near the base when the Firefly is powered on.
The EH has never done this.
Is it important to burn in a tube?
sengo, I'm not a multimeter guy, I have a rawer approach (Wire it - it works - yell in glory!!! :icon_twisted: - it doesn't work - yell in rage!!! :icon_evil: )
So I cannot be of any help with those voltages...
sengo - I'm busy for the next few days but will post some voltages to compare on thursday - unless someone else gets to you first.
Rick
Hi
RE: Yugo tube playing up and "Why does it sound good now?"
Wild guess - A couple of time I've had new tubes that make poor connections into sockets. Once they make contact and get hot and get going, they are OK. Given the low voltages here and high voltages in the firefly, it might have been the plate pins that had a film of corrosion on them or were not making contact.
cheers
Quote from: Jered on June 01, 2008, 10:20:35 PM
Thanks Rick, I wasn't sure what voltage you were running it at and needed the volt reg or not, that's why I asked. Please do post your results after your rehersal, I'll hold off on the vent holes until then.
Thanks, Jered
I ran my red Valvecaster/LPB for 3 hours tonight at rehearsal. Immediatly after unplugging it I opened it up and 'kissed' the 12au7 - lips being very sensitive to heat. It was warm but not hot. The enclosure was colder but a tiny bit warm. My 500ma regulated DC adapter was way hotter. Thats good enough for me - no vents needed. I was running it at 12 volts.
Also, the way I configured the two 3pdt was excellent. The 'bypass' 3pdt cuts of both effects for true bypass, the 'boost' 3pdt brings the LPB in and out. Real Easy to go from
clean to
rhythm (VC) to
lead (LPB > VC).
The other guitarist in my band wants one!
I kissed my tube and it felt good.
YOU PERVERT!!! :icon_wink:
Quote from: frequencycentral on June 04, 2008, 08:57:07 PM
[
I ran my red Valvecaster/LPB for 3 hours tonight at rehearsal. Immediatly after unplugging it I opened it up and 'kissed' the 12au7 - lips being very sensitive to heat. It was warm but not hot. The enclosure was colder but a tiny bit warm. My 500ma regulated DC adapter was way hotter. Thats good enough for me - no vents needed. I was running it at 12 volts.
Also, the way I configured the two 3pdt was excellent. The 'bypass' 3pdt cuts of both effects for true bypass, the 'boost' 3pdt brings the LPB in and out. Real Easy to go from clean to rhythm (VC) to lead (LPB > VC).
The other guitarist in my band wants one!
I kissed my tube and it felt good.
MMMMMMMMMMMMM........that's new Tube kissing in the Stompbox society!!!! :icon_rolleyes:
Quote from: Renegadrian on June 04, 2008, 09:10:44 PM
YOU PERVERT!!! :icon_wink:
Quote from: Jimmy-H on June 05, 2008, 07:13:18 AM
Quote from: frequencycentral on June 04, 2008, 08:57:07 PM
[
I ran my red Valvecaster/LPB for 3 hours tonight at rehearsal. Immediatly after unplugging it I opened it up and 'kissed' the 12au7 - lips being very sensitive to heat. It was warm but not hot. The enclosure was colder but a tiny bit warm. My 500ma regulated DC adapter was way hotter. Thats good enough for me - no vents needed. I was running it at 12 volts.
Also, the way I configured the two 3pdt was excellent. The 'bypass' 3pdt cuts of both effects for true bypass, the 'boost' 3pdt brings the LPB in and out. Real Easy to go from clean to rhythm (VC) to lead (LPB > VC).
The other guitarist in my band wants one!
I kissed my tube and it felt good.
MMMMMMMMMMMMM........that's new Tube kissing in the Stompbox society!!!! :icon_rolleyes:
I am not ashamed. It felt right at the time. I would definately do it again if the occasion arose.
I wrote this on one of the Sparkle Boost topic, in reply to an Andy question about the SB before a Valvy, I think it has to be reported here too...
I run the SB with the 2n5457 in, then my toneless Valvy with vol and gain set at something less than the max.
The SB is a good companion, expecially on solos - high notes are well defined even at its max gain.
You may want to tweak the amp highs, as to get the best results on the E or A string palm muted riffs...
That said both at SB min and max gain.
Quote from: sengo on June 02, 2008, 07:19:14 PM
Hi again,
Sorry I have taken so long to respond about my Valvecaster.
I took some voltages, ans was wondering if anyone could compare theirs to mine? To me it just sounds really poorly biased. I also found out my 9V 500 mA power supply actually runs around 12.6 Volts when not plugged into the jack on my Valvecaster, it is an EH power supply. when the jack and take a reading across the positive terminal and ground I get a reading of 11.05 Volts, but I have gotten readings as low as 10.9V. Here are my voltages:
Pin 1: 7.63V
Pin 2: 0.00V
Pin 3: 0.72V
Pin 4: 0.00V
Pin 5: 10.99V
Pin 6: 4.46V
Pin 7: 0.37V
Pin 8: 0.00V
Pin 9: 5.52V
A lot of these voltages seem to fluctuate slightly while taking them. I don't know if that will help diagnose the problem. I'll try to get a picture up later perhaps, but I don't know how helpful that will be, right now my project sort of looks like an octopus.
Nick
Pin 1: 3.02v
Pin 2: -0.518v
Pin 3: 0.00v
Pin 4: 0.00v
Pin 5: 11.97v
Pin 6: 8.21v
Pin 7: -1.285v
Pin 8: 0.00v
Pin 9: 5.91v
DC power in is reading 11.99v.
Gain at maximum.
Edit: My gain pot is 100K not 50K.
QuotePin 1: 3.02v
Pin 2: -0.518v
Pin 3: 0.00v
Pin 4: 0.00v
Pin 5: 11.97v
Pin 6: 8.21v
Pin 7: -1.285v
Pin 8: 0.00v
Pin 9: 5.91v
DC power in is reading 11.99v.
Gain at maximum.
Edit: My gain pot is 100K not 50K.
Thank you very much Rick, I really appreciate it! It looks like I may have messed up the resistors going to pins 1 and six, seen as my voltages are nearly opposite yours. I've checked them numerous times, but I've made mistakes like that before...
Thanks again,
Nick
Else you could try the vero version if that helps...It's more than verified :icon_wink:
Quote from: Renegadrian on June 01, 2008, 04:22:44 AM
I also tried some tubes labelled 5963 - they work.
but as you can read they're part of the same family.
http://www.nj7p.org/Tube4.php?tube=5963
I just tried this Tube in my Pepper Shredder.
There's not much difference in sound compared to the 12U7 tubes I used.
The tube was a 5963 made by Beckman.
I never heard of this label.
But probably it's a relabeled GE tube (according to google....).
And one good thing about this Tube, is the price.
I payed 4 Euro for one tube, that's cheap (in Holland).
The only difference between a 5963 and a 12AU7 is the maximum plate voltage.
250 V for 5963 And 330 V for a 12AU7.
But eeh... we are running from 12 volts here! ;)
So Adriano it's good that you mentioned this Tube.
And I didn't kissed the Tube ..........Yet ;D
Quote from: Jimmy-H on June 06, 2008, 01:11:36 PM
And I didn't kissed the Tube ..........Yet ;D
Maybe 5963 tubes are better kissers than 12au7's? :-*
Quote from: frequencycentral on June 06, 2008, 01:23:39 PM
Maybe 5963 tubes are better kissers than 12au7's? :-*
Let's see :-* :-* :-*..........Yeah definitely!!!!
:) :D :icon_biggrin: :icon_mrgreen:
Hi everybody,
Has anyone tried some 6112 tubes ? I can't get any sound of it :( Maybe the 6112 does not work at all with low voltage ???? After all tubes are designed for high voltage... :-\
- I've build a Voltage regulator for the heater -> OK : 6,3v, the tube lights up
- At begining I was trying to replace the JFET in the first stage of a working distorsion breadboard project just to test, and as is what not working I build on another breadborad the first stage of the valvecaster without more success I must say. Only difference : I run it at 24V (so I replaced the 220K by a 1M pot to be able to set the bias...)
I've check, double check, and check again pins layout but it is good. (Even tried to invert anod/cathod just to be sure...) I don't get any sound and when trying to bias the tube at half supply voltage, there is almost no drop voltage on the bias pot (24-> 22V with a 1Meg pot set at full), meaning there is almost no current flow through the tube I would say ???
What's you opinion ? Should I forget using these tubes ?
Thanks
Quote from: Darkness, Darkness on June 18, 2008, 02:49:08 PM
Hi everybody,
Has anyone tried some 6112 tubes ? I can't get any sound of it :( Maybe the 6112 does not work at all with low voltage ???? After all tubes are designed for high voltage... :-\
- I've build a Voltage regulator for the heater -> OK : 6,3v, the tube lights up
- At begining I was trying to replace the JFET in the first stage of a working distorsion breadboard project just to test, and as is what not working I build on another breadborad the first stage of the valvecaster without more success I must say. Only difference : I run it at 24V (so I replaced the 220K by a 1M pot to be able to set the bias...)
I've check, double check, and check again pins layout but it is good. (Even tried to invert anod/cathod just to be sure...) I don't get any sound and when trying to bias the tube at half supply voltage, there is almost no drop voltage on the bias pot (24-> 22V with a 1Meg pot set at full), meaning there is almost no current flow through the tube I would say ???
What's you opinion ? Should I forget using these tubes ?
Thanks
Maybe try a different tube. I just built this little circuit and had a similar problem of no/low output w/ a 12at7. I popped in a standard 12ax7 and it fired right up. Not the best sound ever w/ a 12ax7 but at least it works. If you can try different tubes first. They all sound different. Also, what kind of wallwart adapter are you using? My OneSpot adapter works great but the other unregulated 9v and 12v that i had either didn't work or sounded like it was broken. Good power supply is a MUST for this circuit IMHO. Good luck w/ your project.
Aaron
Quote from: aab0mb on June 18, 2008, 03:12:45 PM
Maybe try a different tube. I just built this little circuit and had a similar problem of no/low output w/ a 12at7. I popped in a standard 12ax7 and it fired right up. Not the best sound ever w/ a 12ax7 but at least it works. If you can try different tubes first. They all sound different. Also, what kind of wallwart adapter are you using? My OneSpot adapter works great but the other unregulated 9v and 12v that i had either didn't work or sounded like it was broken. Good power supply is a MUST for this circuit IMHO. Good luck w/ your project.
Aaron
Thanks Aaron, I will try the spare tubes on tomorrow and a 12AX7 to check the circuit if it does not work better.
Concerning the power supply, I use a power supply for electronic labs (?? not sure how to say it in english ?? ? sorry :icon_redface:) It allows to get up to 30V/3A. I set it on 24V and the current limitation status is OK. I've also checked voltage of heater and circuit when everything is powered up and it was OK
let's try this on tomorrow so... :)
Fab
Quote from: Darkness, Darkness on June 18, 2008, 02:49:08 PM
Hi everybody,
Has anyone tried some 6112 tubes ? I can't get any sound of it :( Maybe the 6112 does not work at all with low voltage ???? After all tubes are designed for high voltage... :-\
- I've build a Voltage regulator for the heater -> OK : 6,3v, the tube lights up
- At beginning I was trying to replace the JFET in the first stage of a working distorsion breadboard project just to test, and as is what not working I build on another breadboard the first stage of the valvecaster without more success I must say. Only difference : I run it at 24V (so I replaced the 220K by a 1M pot to be able to set the bias...)
I've check, double check, and check again pins layout but it is good. (Even tried to invert anode/cathod just to be sure...) I don't get any sound and when trying to bias the tube at half supply voltage, there is almost no drop voltage on the bias pot (24-> 22V with a 1Meg pot set at full), meaning there is almost no current flow through the tube I would say ???
What's you opinion ? Should I forget using these tubes ?
Thanks
Hi Darkness,
On page three there was this reply from Jered:
Dano, I forgot to add, I tried 6112 and 6021 tubes and the sounded horrible. That's all.
Jered
So there most be comming some sound out of your tube, even when it sounds like sh*T !!!
I think with 24 volts this tube will sound great.
There has to be something wrong with your build.
Keep in mind that jered only used 9 volts!
I hope that you will find what is wrong! :-\
Quote from: Jimmy-H on June 19, 2008, 09:34:58 AM
Hi Darkness,
On page three there was this reply from Jered:
Dano, I forgot to add, I tried 6112 and 6021 tubes and the sounded horrible. That's all.
Jered
So there most be comming some sound out of your tube, even when it sounds like sh*T !!!
I think with 24 volts this tube will sound great.
There has to be something wrong with your build.
Keep in mind that jered only used 9 volts!
I hope that you will find what is wrong! :-\
Hi Jimmy-H
I was thinking also that with 24 V it should be better...
I tried this morning another 6112 tube without more success. Haven't tried yet some 6021... But I tried a 12AX7 as suggested by Aaron and it works ! So my breadboard project is right :) With half a 12AX7 I managed to make a booster that sounds great !!! Funny as I was thinking it would sound crap if it would sounds.... So I am playing around with a 12AX7 (JJ Electronics). Even funnier....I wasn't using this tube a lot because I thought it was not very good sounding in my Emery Sound amp :D I will try other 12AX7 just to check.... Maybe I will continue my project with 12AX7 ?
I'll keep you posted of my results ;)
Thanks !
Sure do, any entry is welcome!!! :icon_wink:
I added a new VERO version for the double valvy - it should work - Please check it out!!!
In the LAYOUT GALLERY search for TWINCASTER.
PS actually it's 2 layout, with and without the R1 at the beginning at the second stage. Someone said it's better to add that res...
Hi everybody,
Today, I've played with 12AX7...well more in a plexi preamp way than the valvecaster :icon_redface: but I am quite happy with the results :) even if it remains lots of tweaking and tests to try ! Once I've got something well advanced i'll create a thread to share with you without hijacking this thread :P And i will for sure have some question for you :icon_wink:
Anyway just to say it also works great with some 12AX7 tubes : OK for a JJ/Tesla, OK for and EH but it does not work good with a Tung Sol (Breadboard powered at 24V)
This thread is just a killing idea !!!!! Thanks dano12 :)
To be continuated ;)
from Bugera (http://www.bugera-amps.com/index.cfm), the guru of tone:
scroll down to 12ax7Q valves (http://www.bugera-amps.com/_01/tubePage.cfm)!
Quote from: Darkness, Darkness on June 23, 2008, 03:34:31 PM
...Once I've got something well advanced i'll create a thread to share with you without hijacking this thread :P And i will for sure have some question for you :icon_wink:
Well, I believe our admin should change the title of this topic, I think nobody in this forum runs valves from a battery!!! :icon_eek:
So it has turned into what we'd call
"LOW VOLTAGE TUBE CIRCUITS".
Said that, your creations are more than welocmed in this very topic!!!
HINT, HINT: please, change that topic title!!! :-[
Allright, decided to biuld this thing, (valvecaster) but since this thread is 30 pages long Im going to need some clarifications. (I did however read through it)
1. is there a good schematic for this thing including switches and whatnot? It seems to me that everyone is building different versions - im confused.
2. Is 12 V the power you want?
3. I was thinking of adding a switch for tube heating so that it can be kicked in without any delays - necessary?
It would be great if someone could explain and summarize this whole monsterthread a bit. (A huge FAQ for this project would be great for noobs like me)
Quote from: aka_basse on June 24, 2008, 07:01:32 AM
Allright, decided to build this thing, (valvecaster) but since this thread is 30 pages long I'm going to need some clarifications. (I did however read through it)
1. is there a good schematic for this thing including switches and whatnot? It seems to me that everyone is building different versions - I'm confused.
2. Is 12 V the power you want?
3. I was thinking of adding a switch for tube heating so that it can be kicked in without any delays - necessary?
It would be great if someone could explain and summarize this whole monsterthread a bit. (A huge FAQ for this project would be great for noobs like me)
Hi AKA_BASSE
1. Just build the original one on page 1.
You can tweak it from there if you want.
For instance if it's to bassy, make C1 smaller (20nF or 10nF).
You can also make the tone control switchable. (switch between C4 and the connection of C3-VR3).
If you like it without the tone control, You can leave it out.
2.Yep!
3.No, you don't need that.
when you power it up, the tube get it's power also.
the circuit always get it's current.
the only thing that gets bypassed is the signal.(this is with every stompbox)
I hope that this is helpfull!! ;)
Success with your build and keep us posted!
Quote from: aka_basse on June 24, 2008, 07:01:32 AM
Allright, decided to biuld this thing, (valvecaster) but since this thread is 30 pages long Im going to need some clarifications. (I did however read through it)
1. is there a good schematic for this thing including switches and whatnot? It seems to me that everyone is building different versions - im confused.
2. Is 12 V the power you want?
3. I was thinking of adding a switch for tube heating so that it can be kicked in without any delays - necessary?
It would be great if someone could explain and summarize this whole monsterthread a bit. (A huge FAQ for this project would be great for noobs like me)
A couple of weeks ago I trawled this thread and pasted various mod ideas into a Word doc, here's what I saved:
"
I note that the original schematic and layout specify that the triode at pins 1-3 be used for the voltage gain stage, and 6-8 for the follower.
This isn't usually the best way to do it with a 12A*7. With battery power or regulated DC going through the heaters, it doesn't matter which triode you use in which position, but if you're using AC or less-than-pristine DC, the triode at pins 6-8 will be quieter, due to the location of the heater pins on the tube. (You can find mention of this in the data sheets on many 12A*7 series tubes.)
I lower the coupling cap between stages for less bass.
For lowering bass, you could try lowering the value of either the input cap, or the coupling cap between the two tube stages.
I am bypassing the Valvecaster gain pot with a 2.2nf cap. This helps maintain some brightness when the VC gain is turned down. For the input cap on the Valvecaster I am using a combination of caps to give me 2.7nf. This helps tighten up the bottom end.
To tame the gain I would lower R2 and R3. 220k and 100k seem pretty high for a low voltage circuit. Even in a regular high voltage amp the normal value is just 100k. So maybe cut them in half.
if you bring down that 220k to 100k it will def lower the gain a bit. I built mine with both plate r's at 100k.
A 1M gain pot allows massive, saturated gain. A little mushy in the bass frequencies, but pretty cool. I'm considering putting a "more" switch in, whereby it adds a resistor in series to the regular gain pot.
Adding resistance to the plate resistors(R1 and R2) will increase gain. Adding resisitance to VR1, in series with the gain pot, will decrease gain.
guitarx: replace the 100k resistor with 47k. Replace the 220k resistor with 100k.
Beautiful cleans
To fellow Valvecaster experimenters -- I've currently got this circuit on a breadboard, switching out everything and I have some items of interest to report, especially for those looking for more gain.
The nicest clean sound I've found so far, is with the following mods:
R2 = 100k
R3 = 47k
C1 = 0.1uf
Remove C4 and VR2
Finally received that 7812 - mounted with the 100uF filter cap on the dc jack - hiss is just a memory...
put a 100uF cap across the DC jack (positive leg to positive rail, neg. leg to neg. rail), then, instead of connecting the positive rail directly to the circuit, connect it to the regulator's pin1, ground to pin2, and the circuit to pin3. Then screw it on the enclosure. It is a 7812."
I take no credit - its other peoples ideas - I just pulled it together for easy reference.
Quote from: aka_basse on June 24, 2008, 07:01:32 AM
1. is there a good schematic for this thing including switches and whatnot? It seems to me that everyone is building different versions - im confused.
2. Is 12 V the power you want?
3. I was thinking of adding a switch for tube heating so that it can be kicked in without any delays - necessary?
It would be great if someone could explain and summarize this whole monsterthread a bit. (A huge FAQ for this project would be great for noobs like me)
1. Go to the
Layout Gallery and search for VALVECASTER - you'll find my verified vero layouts. Both Tone or Toneless.
Those layouts include jacks, power, switch, so you just cannot fail...
2. Yes
3. no need for that
A FAQ, you say...Well, that could be done...But I just can't figure out what to write about it!!! Maybe we could work at it togheter - you ask, we reply, so we can write down all the Qs' and the As'...
Hope that helps...
PS I'm building my 4th Valvy, a local bass player asked me to build it for him...And the graphics on this one are gonna kick serious a$$!!! I'll post it in some days...
PS Please give a look at my TWINCASTER layouts in the gallery - they should be correct, but hey I need your comments...
Wow thanks alot guys!!
Jimmy -h - Great answers, made everything much clearer
frequencycentral - Wonderful list of tweaks, this is going to save me lots of time (not having to read through the thread all the time) and many others will probably find it useful
Renegadrian - Great layout, will probably follow that one. Can you get the sound of the "no tone" version with the "tone" version? What difference does it make to leave tone out? If Im going to use with both singlecoil and humbucker guitars wouldnt it be smart to leave it in there?
And if I understood correctly the effect will kick in instanly when you stomp it unlike, say, my amp which takes 10 sec before sound?
Thats all the questions I had for now (likely many to come)
once again, thank you all very much!!
edit: also, what kind of caps and resistors should I use?
Renegadrian - Great layout, will probably follow that one. Can you get the sound of the "no tone" version with the "tone" version? What difference does it make to leave tone out? If Im going to use with both singlecoil and humbucker guitars wouldnt it be smart to leave it in there?
Well, the valvy is not so bright, so I had the tone always on 10 - else it will cut off all the highs and just won't cut thru...
Basically you have 2 ways
1. build it with the tone pot - it's very easy to get it out of the circuit if you'll find it useless as it was for me
2. Just go for the toneless version and get all the tone the valve can give...
I have several guitars, both SC and HB equipped, and no, I don't think the tone control is a must...
I use it with my bass too...
And if I understood correctly the effect will kick in instanly when you stomp it unlike, say, my amp which takes 10 sec before sound?
yes the tube will be always powered, as you can tell by the light of the tube itself
what kind of caps and resistors should I use?
standard components are used in this simple circuit.
Oh, before I forget...It was written several times that in order to avoid any hiss/noise, you need a good regulated wall wart, or use a 7812 voltage regulator and a filter cap on the DC jack. That is a must in my valvies...
Quote from: Renegadrian on June 24, 2008, 08:01:21 PM
Renegadrian - Great layout, will probably follow that one. Can you get the sound of the "no tone" version with the "tone" version? What difference does it make to leave tone out? If Im going to use with both singlecoil and humbucker guitars wouldnt it be smart to leave it in there?
Well, the valvy is not so bright, so I had the tone always on 10 - else it will cut off all the highs and just won't cut thru...
Basically you have 2 ways
1. build it with the tone pot - it's very easy to get it out of the circuit if you'll find it useless as it was for me
2. Just go for the toneless version and get all the tone the valve can give...
I have several guitars, both SC and HB equipped, and no, I don't think the tone control is a must...
I use it with my bass too...
There is also the possibility to use a pot with integrated turn-on-switch. I've got one in my emery sound amp, great feature :)
Well, almost everything is possible, but I believe it would be just too much...I think you won't regret the absence of the tone pot...
Well ive been messing around with this circuit today and while its supposed to run at 9 or 12 volts and it sounded ok at those voltages I just thought it was a waste. So I whipped up dano's voltage regulator using the LM317T and used a 5k trim pot because thats all i had on hand. Hooked it up to my bench top power supply and cranked it up to 20vdc.
Set the heaters to about 9v just to get the tube cooking a bit and it sounds pretty good. Im using a 12at7 tube by the way. I think it still needs some tweaking on the input caps and tone stack. The LM317T does need a heat sink so I just made one out of a piece of aluminium i had lying around. Anyway just thought you guys might be interested
Cheers JOHNO
hello again (and thanks for answers again!)
I've decided to keep the tone control. I'll put 3 switches in, was planning on using 1st one to reduce the gain to a clean boost; 2nd one for tone control on/off; 3d one for some other interesting tweak.
Any good tone mods to add to the last switch?
Hey Johno, what voltage regulator do you mean? I'd like to supply mine with more than 12 volts to see what the outcome is. It would be great to have a power supply for the VC that has like a rotary switch for voltage selection.
Cheeb, check page five of this thread. Theres is a schemo there that dano came up with that has the voltage regulator in it. I that schemo dano uses a 6111 tube. Just apply the regulator section to the schemo on page one.
I have a question for dano, with the LM317T the spec sheet says that the tab is conected to the out pin of the regulator so I would think that means I need to keep the tab isolated from ground? Is that correct.
Quote from: aka_basse on June 25, 2008, 12:06:35 PM
hello again (and thanks for answers again!)
I've decided to keep the tone control. I'll put 3 switches in, was planning on using 1st one to reduce the gain to a clean boost; 2nd one for tone control on/off; 3d one for some other interesting tweak.
Any good tone mods to add to the last switch?
What you could do, is to make a input cap selector.
With a rotary switch, just like I did with my Pepper Shredder.
So you can select the amount of bass That comes in.
For the smallest cap you have to use a good ceramic or Silver Mica .
I used a 680pF.
just look here : http://www.diystompboxes.com/smfforum/index.php?topic=63479.500
Quote from: JOHNO on June 25, 2008, 11:14:21 PM
....with the LM317T the spec sheet says that the tab is conected to the out pin of the regulator so I would think that means I need to keep the tab isolated from ground? Is that correct.
That is correct, isolate the tab.
Quote from: Jimmy-H on June 26, 2008, 04:10:49 AM
What you could do, is to make a input cap selector.
With a rotary switch, just like I did with my Pepper Shredder.
So you can select the amount of bass That comes in.
For the smallest cap you have to use a good ceramic or Silver Mica .
I used a 680pF.
just look here : http://www.diystompboxes.com/smfforum/index.php?topic=63479.500
Thanks, sounds nice!
Yeah, all I got ordered is my 3 two way switches, sounds good to dedicate the last one to this. If you'd have to choose one of the caps (other than standard) which one would you make switchable? (which one is the most useful you think?)
This is a nice thread, just about to start my valvecaster build, it seems that voltage regulation is a big issue.
Should I build a voltage regulation box (wall wart 60 or 200 perhaps?) and should I set to voltage to 12.6v?
Quote from: aka_basse on June 26, 2008, 06:14:43 PM
Thanks, sounds nice!
Yeah, all I got ordered is my 3 two way switches, sounds good to dedicate the last one to this. If you'd have to choose one of the caps (other than standard) which one would you make switchable? (which one is the most useful you think?)
I did it with the input-cap.
For the valveCaster it's C1.
Quote from: rm -rp ./Matt* on June 26, 2008, 11:39:26 PM
This is a nice thread, just about to start my valvecaster build, it seems that voltage regulation is a big issue.
Should I build a voltage regulation box (wall wart 60 or 200 perhaps?) and should I set to voltage to 12.6v?
The DC- wall wart should be at least 500 mA.
You could use a LM7812 with a diode (1n4148) on the centre pin (cathode to ground), this sets you up for about 12.6 volt.
And solder it on the input jack for the power supply, together with the 100 uF cap.
Quote from: Jimmy-H on June 27, 2008, 12:56:49 AM
Quote from: rm -rp ./Matt* on June 26, 2008, 11:39:26 PM
This is a nice thread, just about to start my valvecaster build, it seems that voltage regulation is a big issue.
Should I build a voltage regulation box (wall wart 60 or 200 perhaps?) and should I set to voltage to 12.6v?
The wall wart should be at least 500 mA.
You could use a LM7812 with a diode (1n4148) on the centre pin (cathode to ground), this sets you up for about 12.6 volt.
And solder it on the input jack for the power supply, together with the 100 uF cap.
Thanks Jimmy, by the time my tubes come in the mail I should properly know what your talking about and add it to the layout design :) My brain is working overtime learning all this stuff
Quote from: JOHNO on June 25, 2008, 02:44:05 AM
Well ive been messing around with this circuit today and while its supposed to run at 9 or 12 volts and it sounded ok at those voltages I just thought it was a waste. So I whipped up dano's voltage regulator using the LM317T and used a 5k trim pot because thats all i had on hand. Hooked it up to my bench top power supply and cranked it up to 20vdc.
Set the heaters to about 9v just to get the tube cooking a bit and it sounds pretty good. Im using a 12at7 tube by the way. I think it still needs some tweaking on the input caps and tone stack. The LM317T does need a heat sink so I just made one out of a piece of aluminium i had lying around. Anyway just thought you guys might be interested
Cheers JOHNO
Hi JOHNO, you want your heaters at a minimum of 12.2 volts, 12.6 is optimum for 12A_7 tubes. Better sound and longer tube life.
Quote from: Jimmy-H on June 19, 2008, 09:34:58 AM
Quote from: Darkness, Darkness on June 18, 2008, 02:49:08 PM
Hi everybody,
Has anyone tried some 6112 tubes ? I can't get any sound of it :( Maybe the 6112 does not work at all with low voltage ???? After all tubes are designed for high voltage... :-\
- I've build a Voltage regulator for the heater -> OK : 6,3v, the tube lights up
- At beginning I was trying to replace the JFET in the first stage of a working distorsion breadboard project just to test, and as is what not working I build on another breadboard the first stage of the valvecaster without more success I must say. Only difference : I run it at 24V (so I replaced the 220K by a 1M pot to be able to set the bias...)
I've check, double check, and check again pins layout but it is good. (Even tried to invert anode/cathod just to be sure...) I don't get any sound and when trying to bias the tube at half supply voltage, there is almost no drop voltage on the bias pot (24-> 22V with a 1Meg pot set at full), meaning there is almost no current flow through the tube I would say ???
What's you opinion ? Should I forget using these tubes ?
Thanks
Hi Darkness,
On page three there was this reply from Jered:
Dano, I forgot to add, I tried 6112 and 6021 tubes and the sounded horrible. That's all.
Jered
So there most be comming some sound out of your tube, even when it sounds like sh*T !!!
I think with 24 volts this tube will sound great.
There has to be something wrong with your build.
Keep in mind that jered only used 9 volts!
I hope that you will find what is wrong! :-\
hehehe...that was with the sub minis directly replacing the 12AU7's at 9 volts. With a few tweaks and at higher voltages the sub minis sound like little tube amps. Everything from low/mid gain crunchy to high gain endless sustain. I'm in the middle of doing a small write up right now and schems for circuits using 6021's and 5784 pentodes. I was hoping to have the write up done by now but work has been hectic so time has been an issue. Hopefully I'll have it done within a week or so.
I'm in for the high gain circuits...Eager to see your work!!! :icon_wink:
> you want you heaters at a minimum of 12.2v,12.6 is optimum for 12A_7 tubes.
Thanks jered, I thought we were shooting for 6.3v. Is the 6.3 for the 6111 tube is it? I'll crank up the voltage on the heaters a bit more ,Thank you . JOHNO
Quote from: Jimmy-H on June 27, 2008, 12:45:40 AM
Quote from: aka_basse on June 26, 2008, 06:14:43 PM
Thanks, sounds nice!
Yeah, all I got ordered is my 3 two way switches, sounds good to dedicate the last one to this. If you'd have to choose one of the caps (other than standard) which one would you make switchable? (which one is the most useful you think?)
I did it with the input-cap.
For the valveCaster it's C1.
Oh sorry, asked for the wrong thing heh, what I meant to ask was
which value of C1 other than standard 47nF would you choose if you only could choose between two values (a two way switch)
Quote from: JOHNO on June 27, 2008, 07:18:20 AM
> you want you heaters at a minimum of 12.2v,12.6 is optimum for 12A_7 tubes.
Thanks jered, I thought we were shooting for 6.3v. Is the 6.3 for the 6111 tube is it? I'll crank up the voltage on the heaters a bit more ,Thank you . JOHNO
Yeah, the 6111 tube only work with 6.3 volt.
The normal tubes work with 6,3 volt when using the center tap as ground.(this also doubles the current you use)
Otherwise 12.6 volt without the center tap.
Quote from: aka_basse on June 27, 2008, 07:39:22 AM
Oh sorry, asked for the wrong thing heh, what I meant to ask was
which value of C1 other than standard 47nF would you choose if you only could choose between two values (a two way switch)
You could try 2n2 or 4n7.
But you could also try some other values (those caps are not that expensive)
Experiment a littlebit, and when you find the right ones you like, put them in!! ;)
Quote from: Renegadrian on June 27, 2008, 07:00:46 AM
I'm in for the high gain circuits...Eager to see your work!!! :icon_wink:
Yep so am I!!!
:D
Jimmy, and all my fellow tube friends, did you check the VERO double valvy layout I added in the gallery?
it should work but I'd like you to check it...
In the LAYOUT GALLERY search for TWINCASTER.
PS actually it's 2 layout, with and without the R1 at the beginning at the second stage. Someone said it's better to add that res...
Quote from: Renegadrian on June 27, 2008, 05:58:42 PM
Jimmy, and all my fellow tube friends, did you check the VERO double valvy layout I added in the gallery?
it should work but I'd like you to check it...
In the LAYOUT GALLERY search for TWINCASTER.
PS actually it's 2 layout, with and without the R1 at the beginning at the second stage. Someone said it's better to add that res...
Hi Adriano,
Sorry that I didn't check it earlier.
I never use stripboard.
But as far as I can see, the layout should work!! ;)
I used this schemo to check:
(http://i301.photobucket.com/albums/nn69/Joppes60/twincaster.gif)
Yes, that's from that schem - thanks for checking, Jimmy!!! I appreciated that...(http://digilander.libero.it/le.faccine/faccinea/amici/103.gif)
Hi,
do you think it's possible to supply the heat circuit of 12ax7 with only 3,3V for one triode section?
I ask this because the cooltron serie of Vox, use this technic to decrease current consumption.
Quote from: stephanovitch on July 01, 2008, 11:56:27 AM
Hi,
do you think it's possible to supply the heat circuit of 12ax7 with only 3,3V for one triode section?
I ask this because the cooltron serie of Vox, use this technic to decrease current consumption.
3.3v for one triode? There are two triodes in a 12ax7, therefore 3.3v for each is 6.6v right? The two triodes share a common heater - you could supply the heater with 6.6v using the centre tap, but 6.3v is preferable. However, using the centre tap at 6.3v consumes 300ma, whereas using 12.6v and not using the centre tap uses just 150ma.
Having said that, running the entire circuit at 9v ( as some people do, including myself) give the heater just 9v, and the circuit works just fine.
So, the rule seems to be: less
volts = more
ma
.......................although interestingly enough, all the Cooltron range are rated at 95ma...............
http://www.voxamps.co.uk/pedals/cooltron.asp
Quote from: frequencycentral on July 01, 2008, 01:34:42 PM
Quote from: stephanovitch on July 01, 2008, 11:56:27 AM
Hi,
do you think it's possible to supply the heat circuit of 12ax7 with only 3,3V for one triode section?
I ask this because the cooltron serie of Vox, use this technic to decrease current consumption.
3.3v for one triode? There are two triodes in a 12ax7, therefore 3.3v for each is 6.6v right? The two triodes share a common heater - you could supply the heater with 6.6v using the centre tap, but 6.3v is preferable. However, using the centre tap at 6.3v consumes 300ma, whereas using 12.6v and not using the centre tap uses just 150ma.
Having said that, running the entire circuit at 9v ( as some people do, including myself) give the heater just 9v, and the circuit works just fine.
So, the rule seems to be: less volts = more ma
First, VOX uses 12Au7 TUBES.
I don't think 12AX7 sound very well with that low voltage.
I never tried to use a heater voltage of 3.3 volts.
But eeh the VOX pedals are working!
I don't know how it sounds.
Less voltage isn't always more Current.
Because if you use 9 volts without the centre tap, the current Will be less then 300 mA.(just maths ;) )
So just try, and let us know, what it sounds like with 3.3 volt!!
"Here's what makes the COOLTRON system tick. The COOLTRON circuit basically operates by using two very special signal paths. The first is the "servo circuit," which provides the right conditions between the plate of the tube and the grid. This achieves controllable, stable parameters for the tube and provides the correct operating conditions for the tube to function as it would if run at a higher voltage. The second circuit is a patented power supply that provides a low voltage, low current supply to the heater elements in the tube. Since the tube is now running at such a reduced supply level, the anode current is much smaller than normal. This means that the amount of heat required at the cathode to achieve sufficient cathode current emission is much smaller – hence the ability to run the heaters at a lower level and for COOLTRON pedals to run for 16 hours on 4 x AA batteries!"
Quote from: frequencycentral on July 01, 2008, 04:56:49 PM
"Here's what makes the COOLTRON system tick. The COOLTRON circuit basically operates by using two very special signal paths. The first is the "servo circuit," which provides the right conditions between the plate of the tube and the grid. This achieves controllable, stable parameters for the tube and provides the correct operating conditions for the tube to function as it would if run at a higher voltage. The second circuit is a patented power supply that provides a low voltage, low current supply to the heater elements in the tube. Since the tube is now running at such a reduced supply level, the anode current is much smaller than normal. This means that the amount of heat required at the cathode to achieve sufficient cathode current emission is much smaller – hence the ability to run the heaters at a lower level and for COOLTRON pedals to run for 16 hours on 4 x AA batteries!"
Hee Rick you really did your research!!!! :icon_wink:
I don't know if you agree with me, but I have a bad opinion about those hybrid pedals, the Valvy is special to me as all the sound comes from the tube only, and the tube itself is not surrounded by trannies and other things...
Quote from: Renegadrian on July 01, 2008, 06:30:09 PM
I don't know if you agree with me, but I have a bad opinion about those hybrid pedals, the Valvy is special to me as all the sound comes from the tube only, and the tube itself is not surrounded by trannies and other things...
Yes Adriano I agree - the less components the better.
At the moment I'm working on a circuit which may be of interest - a single tube tremolo - 9 volt of course. The one on the breadboard uses a 6111 but I will use a 12au7 for the finished pedal. It uses a LM13700 VCO, and has two speeds, selectable by stompswitch. It slowly speeds up/slows down when you stomp the speed change switch. There is a nice light valve crunch if you play harder. I will post it when its finished!
Great work freq ,its crossed my mind to make a valve trem like in the old fenders but im not that switched on yet. Im just wondering how long it will be before some company stooge gets hold of the valvy and we start seeing them in the stores.
So, who is going to be the first to do a valvecaster->386->1 to 1 matching transformer?
There's magic to be found there....
Hi Dano12, I was just wandering if it would be ok to add a phase inverter stage, possibly plugged in a 1:1 transformer at the end of a valvecaster or valvecaster-like ;)
I need more parts to test this....I will have to wait for my next parts order ! By the time, do you think the idea of the phase inverter / transformer is relevant in such circuit ?
Quote from: dano12 on July 01, 2008, 10:45:04 PM
So, who is going to be the first to do a valvecaster->386->1 to 1 matching transformer?
There's magic to be found there....
I'm puzzled here... a transformer after a 386? ???
I had a few thoughts about adding an impedance matching transformer after my cleaned out version of the valvecaster that will create a tube DI, but after a 386? what's the deal there?
gaah!
Took long enough for the banzai shipment, (with several items backordered - including the tube). When I finally get it.... there's no box. They forgot the box. Getting pretty pissed...
Quote from: aka_basse on July 03, 2008, 08:54:31 AM
gaah!
Took long enough for the banzai shipment, (with several items backordered - including the tube). When I finally get it.... there's no box. They forgot the box. Getting pretty pissed...
For my last orders some items were back ordered too. It took a bit more than one week to be shipped ... and most of the time I usually get the back ordered parts in a separate shipment (at no extra shippment costs) Last time I thought they forgot one item (as they did not have noticed it on the order list as they usually do) But I finally got it a couple of days later
personaly I think the service is good :) but you need a bit of patience ;) Good luck !
Quote from: Darkness, Darkness on July 03, 2008, 09:02:28 AM
Quote from: aka_basse on July 03, 2008, 08:54:31 AM
gaah!
Took long enough for the banzai shipment, (with several items backordered - including the tube). When I finally get it.... there's no box. They forgot the box. Getting pretty pissed...
For my last orders some items were back ordered too. It took a bit more than one week to be shipped ... and most of the time I usually get the back ordered parts in a separate shipment (at no extra shippment costs) Last time I thought they forgot one item (as they did not have noticed it on the order list as they usually do) But I finally got it a couple of days later
personaly I think the service is good :) but you need a bit of patience ;) Good luck !
Yeah, I've only shopped there once before, that time everything worked perfectly. I only wish they had some kind of stock info about the parts available.
Don't feel so bad.
My last order from Small Bear was the opposite.
They sent the box and forgot the rest of the order.
Quote from: LMJS on July 03, 2008, 09:28:32 AM
Don't feel so bad.
My last order from Small Bear was the opposite.
They sent the box and forgot the rest of the order.
hahah ok, now thats definitely worse
Yeah, excellent service after all, shipped the box straight away :icon_biggrin:
(http://einarkramer.890m.com/UsePage/50px-Skull_and_crossbones.png) Valvecaster IV (http://einarkramer.890m.com/UsePage/50px-Skull_and_crossbones.png)
I made this for Santa Pazienza bass player - It's a local band here in Rome - it means "Holy Patience"
Took their logo, swapped the candle for the tube...et voila'!!!
(http://img297.imageshack.us/img297/6206/diyforumva6.jpg)(http://a892.ac-images.myspacecdn.com/images01/63/l_162c162cad4a3e14c6896317a397dbf3.jpg)
Really looks great Adriano!
Nice job!! :icon_wink:
Yes great job ! Happy bass player ! :)
So I just ordered me a tube and socket finally, after this thing goign 32 pages I will take on a valve caster. i already have a pretty cool enclosure for it too! should come out looking pretty neat.
anyone TRY it with batteries?
of course its going to chew through them, but i could see this going on a mini busking pedalboard, so long as it doesnt blast through batteries any faster than my rc-2 loop station.
Quote from: letsgocoyote on July 15, 2008, 11:36:59 PM
anyone TRY it with batteries?
I got 6 minutes. Once the battery starts going, the voltage output drops and the sound becomes mush.
figures. i wonder what difference perhaps 6AA batteries could make instead. regardless im excited for the build
Quote from: letsgocoyote on July 16, 2008, 02:59:16 AM
regardless im excited for the build
It's a great build. I gave my twin channel version to a friend for his birthday, so now I have an excuse to build another for myself :icon_mrgreen:
I'm going with a no-tone pot tagboard version this time.
Quote from: andrew_k on July 16, 2008, 03:20:56 AM
I'm going with a no-tone pot tagboard version this time.
No tone Valvy? (http://digilander.libero.it/le.faccine/faccinea/perplesso/1122.gif)
Well...Follow my layout then!!! :icon_wink:
I am so happy I built mine without that 3rd pot...
oo mine is turning out nicely... if I had a good camera at hand I would give you a little look inside (its pure spaghetti mayhem)
Havent got a tube to test it with, so I have no idea if its working or not. But its pretty neat on the outside, always something ei?
Here is a picture of the layout, I took renegadrians layout and modded a bit, and put the parts on a board. Probably not the easiest way to build this thing but hey
3 switches for different mods, tone on/off, 2 different input caps and 2 different values on R1&R2
(http://i18.photobucket.com/albums/b110/aka_Basse/render.gif)
Hi aka bass,
Sure looks like a lot of fun!!
Bur where are the meatballs?? ???
No spaghetti without the balls!!
No just kiddin'.
Just let us know how it all sounds like!
And I'm very curious how it gonna look altogether!
have fun building it!!
Quote from: aka_basse on July 16, 2008, 12:10:58 PM
Here is a picture of the layout, I took renegadrians layout and modded a bit, and put the parts on a board. Probably not the easiest way to build this thing but hey
3 switches for different mods, tone on/off, 2 different input caps and 2 different values on R1&R2
(http://i18.photobucket.com/albums/b110/aka_Basse/render.gif)
Your point to point layout is very cool! Thanks for sharing!
Quote from: Krinor on February 22, 2008, 10:29:35 AM
Okay, here's another little mod for the Valvecaster:
A usefull tonal variation can be achieved by implementing a switchable negative feedback.
Put a 22k resistor and a spdt switch between the output and the cathode of the second stage (lug 8 ).
You can also make a "bass boost" filter out of it by inserting a capacitor between there as well.
I currently have a 0.056uF cap in series with the resistor. This removes some of the mid range and helps keep things a little bit more together. It sounds nice and clean at low gain settings and it also sounds pretty good with everything maxed. More defined puch in the bottom and not so shrill. I've tried this with larger caps as well but it tends to get a bit too boomy.
All in all this is a nice little mod which will tame the gain a bit. Nothing dramatic, but it helps if you want to tune the thing for a more clean boost.
I'm interested in the use of this negative feedback idea. Is this similar to the theory behind the inverting input on an opamp, where what you feed back suppresses what comes out again? So by allowing high frequencies through with a capacitor you actually suppress them in the output?
Would there be a way to insert a more intricate tone shaping network, possibly bleeding highs to ground to accentuate them at the output? Is there a way to implement something like the feedback loop of the Rat distortion, where there are different gains for different parts of the frequency spectrum?
I'm I completely off base here?
I've explored the negative feedback idea some on my own. It could all be for naught, as I'm not sure that the theory is sound. But based on my work with inverting opamp circuits, and the fact that someone suggested negative feedback in this one, I've come up with my own variation.
The schematic below is the Valvecaster with the following modifications:
Input cap reduced from 47nF to 10 nF to tame bass.
Coupling cap reduced from 47nF to 6.8nF to further tame bass fed to second gain stage.
Negative feedback network established between output of second gain stage and cathode (pin 8) to reduce gain in this stage and to shape frequency response.
The idea behind this is to make up for loss of bass in the eariler stages. It won't distort so much in the bass and get flabby, but I still want a full bottom end. This will also add some top end sparkle (apparently) because of the dip in the mids.
The feedback is a bell curve bandpass, with the lows being slightly more attenuated than the highs. This of course, should have the opposite effect on the output, giving a mid dip (hopefully not a scoop) with a good amount of bass and treble.
I don't have the resources to build this at the moment, so if anyone gives it a shot, please post the results. Also, if my theory is totally flawed, let me know.
Here's the schematic - I know it says +9V, but I intend to build it at 12V. Also, for a slightly flatter response, change the 200k resistor in the feedback network to 500k. This is probably where I'll start.
(http://i78.photobucket.com/albums/j93/joeydail268/IMG_5538.jpg)
Interesting!
I'll have to get your mods on the breadboard next week... I like the idea a lot ;D
I wanted to trie it with a 12ax7/ecc83 tube since my 12au7 is on its way. During this test I made 2 mistakes:
I mounted the DCplug the wrong way on the adapter, and I had wired one of the + wires to the wrong pin on the dc jack (thought that both + pins had connection all the time). So when I fixed this it still doesnt work - did I blow the 7812? It got pretty warm! How do I test the regulator without taking it out? (its buried beneath the cable spaghetti)
The led never lit, and I tested and it was in the right "direction".
!!edit: Ok never mind, im too stupid for this kind of stuff. Wired the + wires from the wrong pin AGAIN, but now the LED lights and everything. But there is no sound whatsoever. Can this be because of the 12ax7? If the box worked it would still give me some sound with this tube, right?
YES!!! It works!!! Playing with 12ax7 now, cant wait to my hands on a 12au7!
Sitting and measuring values and thinking and going mad... and then - without doing a thing - I plugged it in... and it worked!
12ax7??? Hey, how did you make it work??? How's the sound? And how much gain?
In the standard circuit the ax7 was too "boomy" and the sound was really bad...
aka_basse,
I'm curious too. The EH AX7 I was using didn't sound to good. the EH AU7 sounds much better. Did you use the layout you posted?
Quote from: Renegadrian on July 18, 2008, 01:11:19 PM
12ax7??? Hey, how did you make it work??? How's the sound? And how much gain?
In the standard circuit the ax7 was too "boomy" and the sound was really bad...
Well, to me it sounds pretty ok. Its the standard curcuit with a few switchable mods, (including your favorite the tone-knob killer). Using it with the clean channel of my amp (valvestate 80v) works great, the channel otherwise sounds pretty boring. The valvecaster added some compression and with gain up I got a pretty good crunchy tone (the bass sounds kinda bad, but it always has on the clean channel). Used as a booster on the lead channel I actually think my stratoblaster made a better job (and together there is way too much wierd noise and distortion). So it wasnt bad. Perhaps not that amazing, but Ill have to compare it to another tube to get some perspective. Same goes for the gain, hard to say without comparing. The tube I use is a Marshall. The whole reason why Im not using a 12au7 is because im waiting for my order from banzai, and I wanted to see if the box worked.
One problem is hum when used with lead channel of amp. I have a voltage regulator in it, so is it just bad wiring or something?
On my side, thanks to this thread, I've played with 12AX7, more in a marshall plexi configuration than a valvecaster I must admit... and it works very great on my Emery Sound super baby heads: BIG sound :o amazing ! :) But when trying it on the clean channel of my Marshall JCM900 it sounds awfull...a thin light dirty clean sound instead of the big roar... It looks like the gain from this setup (powered in 24V) is not so high in the end.
Is it the same for you guys who tried some 12AX7 in the valvecaster ? Or maybe it is linked to the plexi design : I believe the distorsion is coming for a major part of the power section of this amp, not the preamp ? Well the "only" 24V" might be in cause too.... but regarding the so good results on the emery sound (which was my first goal) I 'll continue experimenting in this direction.
In my next parts order, I will try to add a phase inverter section with negative feedback ... and see what is happening.... For the moment I am trying to understand how phase inverters and output transformer works and what I could try ??? ??? ??? ??? I wander if an isolation transformer right after a classic marshall phase inverter design (so without power amps tubes...) could work in a stompbox design ??? ??? Yeah, that's a pretty strange (maybe stupid) idea I have.... :P ;D
Anyway, once I'll have my final build, I'll share with you guys !
Finished my take on the PEPPER SHREDDER using my layout here http://www.aronnelson.com/gallery/main.php/v/Schematics-etc/PEPPER+SHREDDER.jpg.html (http://www.aronnelson.com/gallery/main.php/v/Schematics-etc/PEPPER+SHREDDER.jpg.html)
It works, altough I forgot to add C10 (220uF electrolytic) between 12v and ground. (I'll update the layout soon)
Put it in, and added a 7812 at the DC jack, I got a really good overdrive, but a countinuous hiss is coming as soon as I put the wall wart into the DC jack...
Any hiss hint??
Heres some pictures of mine, more in the pictures thread
(http://i18.photobucket.com/albums/b110/aka_Basse/box1.jpg)
(http://i18.photobucket.com/albums/b110/aka_Basse/box5.jpg)
aka_basse - where do you get those rails? And also the small tube protector? I like the look of the tube sticking out, but don't think I'd be comfortable without that kind of support.
Thanks,
Joey
Anyone gotten a chance to try out my mods? I've got tubes coming, but I can't wait to know if it works!
Great looking pedal aka. A design after my own heart with roll bars and tube on top.
Those toggles are well protected too.
You can lower the height of the tube by using standoffs on the inside.
(http://www3.telus.net/david65/pedal-pics/shakatube/shaka-tube-34.jpg)
(http://www3.telus.net/david65/pedal-pics/bullitt/Tubesocket2.jpg)
Pushtone: Yeah, got the rollbar inspiration from the pedal you posted earlier in this thread
Thanks for the standoff-idea, might do that if Im starting to stomp away the tubes!
Comfortably numb: The rail is a drawerhandle, and the tube protector came with the socket (along with a cover to put over the tube as well)
Valvecaster V
(http://img353.imageshack.us/img353/3518/260717mb0.th.jpg) (http://img353.imageshack.us/my.php?image=260717mb0.jpg)(http://img244.imageshack.us/img244/6595/260718ju3.th.jpg) (http://img244.imageshack.us/my.php?image=260718ju3.jpg)
Man, I love flames...
Looks great!
Where does one get those rollbars?
Also is there much of a difference? I have read the thread and there clearly is. I wanna know though if it is worth to build a dual "Caster". One with a 12AU7 one with a 12AT7...
Quote from: kurtlives on July 26, 2008, 01:41:28 PM
Looks great!
Where does one get those rollbars?
Also is there much of a difference? I have read the thread and there clearly is. I wanna know though if it is worth to build a dual "Caster". One with a 12AU7 one with a 12AT7...
Those are just drawer handles, you can find them at most hardware stores..
i think home depot carries pink ones with hearts if you really want to be cool ;D
If I use Renegadrian's schematic for varo with no tone and I want to run it at 9v do I have to modify the circuit in any way?
No man, just go straight following the layout...you can run it at 9 or 12v - altough we prefer 12v for the heaters, it will work good at 9v.
Let us know when you've done!!! :icon_wink:
I discovered that there's also a 9AU7 tube - maybe it's less common, but I believe it could be used well for our projects?
After all, it shares all the 12AU7 details but the heater voltage...
http://www.nj7p.org/Tube4.php?tube=9AU7
Quote from: Renegadrian on July 30, 2008, 07:23:16 AM
I discovered that there's also a 9AU7 tube - maybe it's less common, but I believe it could be used well for our projects?
After all, it shares all the 12AU7 details but the heater voltage...
http://www.nj7p.org/Tube4.php?tube=9AU7
How interesting. I do feel sometimes that everyones 12au7 Valvecasters running at 9 volts will one day all fail! A quick worldwide Ebay search shows a decent number of 9AU7s, cheap - but all in the USA.
Awesome Matsumin pedal and my first non-looper build
(http://i264.photobucket.com/albums/ii166/_FlyingZ/Pic2.jpg)
(http://i264.photobucket.com/albums/ii166/_FlyingZ/Pic3.jpg)
(http://i264.photobucket.com/albums/ii166/_FlyingZ/Pic1.jpg)
The wires grew a bit ;)
Nice one!
How did you do such a clean job of those cutouts in the enclosure?
Thanks, I drilled three 1/2" holes and filed the remainder. Two holes for the sides.
VERY NICE INDEED!!! :icon_wink: LOOKS GREAT...
GOOD WORK ON THOSE CUTOUTS!
This has most likely been covered in this thread (I didn't feel like browsing the 30-some pages to see) but after being fed up with the lackluster sound of my valve caster (I had tried numerous different types of tubes, mods, input cap values, etc...), I decided to wire up two 9 volts and try running mine at 18 volts. Holy crap- it sounds.... thousands of times better. It sounds awesome! Highly recommended.
Quote from: MikeH on August 15, 2008, 10:47:32 AM
This has most likely been covered in this thread (I didn't feel like browsing the 30-some pages to see) but after being fed up with the lackluster sound of my valve caster (I had tried numerous different types of tubes, mods, input cap values, etc...), I decided to wire up two 9 volts and try running mine at 18 volts. Holy crap- it sounds.... thousands of times better. It sounds awesome! Highly recommended.
Yeah, I think so too. I've been playing about with 6111 submini tubes and switched capacitor voltage convertors to get the plate voltage up to 44 volts. I think this helps with the linearity/symmetry of the waveforms. Apparently tubes like higher voltages!
This is an experiment I did recently, the input waveform was a triangular wave, I decided that 30 volts was really good enough for my purposes, there's not much difference once you get above that. The law of diminishing returns:
(http://i210.photobucket.com/albums/bb292/frequencycentral/10441234.jpg)
Maybe I'll try four 9 volts... ;D
Quote from: MikeH on August 15, 2008, 11:28:15 AM
Maybe I'll try four 9 volts... ;D
Or just one 9 volt, a MAX1044 and some caps n diodes...........
Can the heaters take 18V?
Quote from: kurtlives on August 15, 2008, 11:35:59 AM
Can the heaters take 18V?
No - 12.6 maximum. But the heaters are powered seperately. At least that's how i do it.
Cool thats what I figured...
I bought a 12V DC 300mA adapter today...is 300mA enough?
Quote from: kurtlives on August 15, 2008, 01:55:24 PM
Cool thats what I figured...
I bought a 12V DC 300mA adapter today...is 300mA enough?
Yup thats good enough, each 12#7 consumes 150ma @ 12 volts. Is it regulated? If not you may want to use a 7812. Also, always a good idea to use a decoupling cap across the power rails. I use 10uf.
Correct me if I'm wrong, but in this design powering up the heaters would be just for aesthetics, would it not? Not that there's anything wrong with doing something just for aesthetics; I'm a big fan of doing just that. :icon_biggrin:
But is there any "sonic" advantage to it?
Again I'm sure it's been covered somewhere in the previous 30 pages, just... you know... lazy!
Quote from: MikeH on August 15, 2008, 03:29:56 PM
Correct me if I'm wrong, but in this design powering up the heaters would be just for aesthetics, would it not?
The heaters are essential for operating a vacuum tube. Without the heaters there would be no electrons for the anode/grid/cathode to play with.
I hope that's what you're asking.
Putting an LED behind the tube would be the kind of thing you'd want to do for aesthetics.
Yes, for high voltage vacum tube operation, but at 9V the heaters aren't necessary, right?. Don't the heaters get voltage from pin 9? Which is left disconnected in the original design. I could be totally mistaken.
Edit: Okay, pin 9 is for the heater centertap. Pins 4 and 5 are for the heaters for each triode.
Quote from: MikeH on August 15, 2008, 04:08:11 PM
Yes, for high voltage vacum tube operation, but at 9V the heaters aren't necessary, right?. Don't the heaters get voltage from pin 9? Which is left disconnected in the original design. I could be totally mistaken.
Yes MusicAudio is right, without heaters the electron won't get 'excited' enough to do anything. The tube won't. work.
Pin 9 is left unconnected in this (and many other tube circuits using 12#7) because it is the 'centre tap' for the filament - using the centre tap and pin 4 you can power the heater at 6.3 volts/300ma. Using pin 4 and 5 you can power the heater at 12.6 volts/150ma.
EDIT: OK you got it, I was typing as you were editing!
Quote from: frequencycentral on August 15, 2008, 02:12:16 PM
Quote from: kurtlives on August 15, 2008, 01:55:24 PM
Cool thats what I figured...
I bought a 12V DC 300mA adapter today...is 300mA enough?
Yup thats good enough, each 12#7 consumes 150ma @ 12 volts. Is it regulated? If not you may want to use a 7812. Also, always a good idea to use a decoupling cap across the power rails. I use 10uf.
Its not regulated but I am adding a little regulating board. Add 0.1mF at the start and a 100mF cap after the regulator.
Having a bit of an issue with my Valve Caster I just finished... :icon_cry:
It doesn't make any sound when engaged...
I get sound though at lug two of the volume pot (output) when I audio probe it. It is much louder than when I probe the inout cap. It is so faint there I can barely hear it. As I go along the circuit it gets louder so that must be good I think.
I get sound also on pin 5, it is very odd... Pin 5 is a heater that is directly connected to B+... This seems like an issue.
Also when all voltages on the pins are super low compared to Rick's postings before (his were like 12V on some spots where as mine were 0.124V)... Btw my readings were with a tube installed...
Its a stock build besides a 4.7mF in parallel with the gain pot to boost gain and a little variable B+ circuit I made.
Help please...
Chris, post your voltages and any changes you have made. Best set that variable B+ to 12 volts for your voltage readings (and remove the 4.7mF in parallel with the gain pot), that way the circuit should be similar to mine. You're not varying the voltage to the heater (pin 5) are you? Pin 5 needs to be an unvarying 12 volts.
Quote from: frequencycentral on August 17, 2008, 06:20:48 PM
Chris, post your voltages and any changes you have made. Best set that variable B+ to 12 volts for your voltage readings (and remove the 4.7mF in parallel with the gain pot), that way the circuit should be similar to mine. You're not varying the voltage to the heater (pin 5) are you? Pin 5 needs to be an unvarying 12 volts.
I am using an unregulated 12V DC power supply...It can shoot upwards of 16.5V DC.
With my variable B+ design the overall voltage gets adjusted, I cant set the heaters independently. From my understanding the heaters can work if they recieve too much or too little voltage, it just affects tube life.
All test so far have had the B+ at 13.7V...
Ill readjust and get voltages...
B+ 12.58V DC
1. 0.2V
2. 0V
3. 0V
4. 0V
5. 0.2V
6. 0.2V
7. 0V
8. 0V
9. 0.1V
Btw without a tube in the voltage seem reasonable considering the circumstances.
Quote from: kurtlives on August 17, 2008, 06:37:09 PM
B+ 12.58V DC
1. 0.2V
2. 0V
3. 0V
4. 0V
5. 0.2V
6. 0.2V
7. 0V
8. 0V
9. 0.1V
Btw without a tube in the voltage seem reasonable considering the circumstances.
Here's mine again:
Pin 1: 3.02v
Pin 2: -0.518v
Pin 3: 0.00v
Pin 4: 0.00v
Pin 5: 11.97v
Pin 6: 8.21v
Pin 7: -1.285v
Pin 8: 0.00v
Pin 9: 5.91v
Your voltages are extraordinary. They were taken with the tube in, yes?
The first thing I would say is that I think giving the heaters anymore than 12.6 volts is bad - giving them less would shorten the life - but giving them more will probably burn them out - like a lightbulb thats rated at a certain voltage if you give it too much. You need to set the heater independently at 12 volts. Maybe you should consider a 7812 voltage regulator for that.
Is the heater glowing?
I just did a quick test on a tube that I know to work. Not in a circuit, just the tube. The resistance between pins 4 and 5 reads
10 ohms. The resistance between pins 4 and 9 (the heater centre tap) reads
5 ohms. Thats a healthy heater. Take your tube out and do this test, post your results.
I've noticed that this circuit doesn't like some power supplys - my brother tried one which seemed appropriate but all he got was hum, we plugged it into my power supply and it worked fine. You should run it from a (new) 9 volt battery, then we can concentrate on if the problem is just the circuit or the power supply.
It occurs to me that nearly all you voltages are 0 volts - I don't know what happens if you blow a tube heater - but maybe it shorts out the whole tube, and therefore the entire circuit - which would explain your short circuit. If you circuit shorts, it may cause your power supply to fail and/or shut down. Pins 1, 5 and 6 should be reading at least some reasonable positive voltage, as they are closest to the power supply. If there's nothing at pin 5 the heater isnt powering up, the electrons wont get excited! they won't do their thing.
Yes I had a tube in... Ill try that test you suggested.
The heater does not glow at all.
I have another 12AU7 and more power supplies (and a battery) that I can try.
My power supply is 300mA...is that enough..what does your draw? Earlier in the thread someone said 500mA is the minimmum.
Quote from: kurtlives on August 17, 2008, 07:16:05 PM
The heater does not glow at all.
Try just powering the heater from a battery, +ve to pin 5, -ve to pin 4, with the tube out of the circuit. Turn your room lights out. The warm up time of the heater is 11 seconds. If it hasn't lit up within 30 seconds its dead.
Quote from: kurtlives on August 17, 2008, 07:16:05 PM
supply is 300mA...is that enough..what does your draw? Earlier in the thread someone said 500mA is the minimmum.
Using pins 4 and 5, the current draw is 150ma.
EDIT: Although pin 9 is not connected in this circuit, it will show a voltage of approximately half the voltage going into pin 5. Make sure pin 9 (or its socket tab) isnt touching anything else,
12AU7 datasheet: http://www.guitaramplifierblueprinting.com/files/GE-12AU7.pdf
Quote from: kurtlives on August 17, 2008, 07:16:05 PM
The heater does not glow at all.
My power supply is 300mA...is that enough..what does your draw? Earlier in the thread someone said 500mA is the minimmum.
http://www.nj7p.org/Tube4.php?tube=12AU7
It seems a heater issue...check back all the connections, either build my verified vero layout and remove that extra cap (you can install it back when it's workin')
Threw in a battery and it works... yeah!
There was a lot of gum though...it stopped when I touched a ground point thouhg, so I gotta figure that one out.
Did this not work because the power supply could supply enough current?
Quote from: kurtlives on August 17, 2008, 07:46:25 PM
Threw in a battery and it works... yeah!
Excellent!
Quote from: kurtlives on August 17, 2008, 07:46:25 PM
There was a lot of gum though...it stopped when I touched a ground point thouhg, so I gotta figure that one out.
Gum I can live with, it's
hum I hate. Bad earthing somewhere.
Quote from: kurtlives on August 17, 2008, 07:46:25 PM
Did this not work because the power supply could supply enough current?
I don't think tubes like unregulated, unfiltered power supplies. You need a really good supply for this one.
I was using a LM317...
I tried another 300mA 12V DC power supply and got low voltages again...
I guess I gotta buy a third power supply... (this will be the 3rd one in 2 days :icon_evil:)
Can you measure how much the effect is drawing for me?
Quote from: kurtlives on August 17, 2008, 08:01:32 PM
I was using a LM317...
That should keep the voltage stable - just don't give the heater more than 12.6 volts.
Quote from: kurtlives on August 17, 2008, 08:01:32 PM
Can you measure how much the effect is drawing for me?
Tell me how and i will - not sure how to do this - I'm going from the datasheet on curent draw.
FYI, I am able to run two 12AU or two 6111 from my 12 volt / 500ma wallwart with ease.
Going to bed now - it's 1am her in the UK!
I'm in a bit of a quandry here.....
I really want to build this pedal (as well I probably will) - my problem is this:
My pedalboard is run by 2 Voodoo Labs Pedal Power II's - I have the option of 9v or 18v....if I want 12v I'll have to add a wall wart to the operation somewhere - not my best option.
Is there a way to run 18v into the circuit but "resistor" it down so it only sees 12v input ?
Thanks, Dan
Quote from: frequencycentral on August 17, 2008, 08:09:54 PM
Quote from: kurtlives on August 17, 2008, 08:01:32 PM
I was using a LM317...
That should keep the voltage stable - just don't give the heater more than 12.6 volts.
Quote from: kurtlives on August 17, 2008, 08:01:32 PM
Can you measure how much the effect is drawing for me?
Tell me how and i will - not sure how to do this - I'm going from the datasheet on curent draw.
FYI, I am able to run two 12AU or two 6111 from my 12 volt / 500ma wallwart with ease.
Going to bed now - it's 1am her in the UK!
You set your meter to measure current and put it in series with the B+.
I measure the current draw with a battery and it was only 0.12A... My power supply should work fine, :icon_evil: :icon_evil: :icon_evil:
Thanks for the help btw
Quote from: danielzink on August 17, 2008, 08:15:01 PM
I'm in a bit of a quandry here.....
I really want to build this pedal (as well I probably will) - my problem is this:
My pedalboard is run by 2 Voodoo Labs Pedal Power II's - I have the option of 9v or 18v....if I want 12v I'll have to add a wall wart to the operation somewhere - not my best option.
Is there a way to run 18v into the circuit but "resistor" it down so it only sees 12v input ?
Thanks, Dan
You can use the 18V supply and add a LM7812 regulator inside the pedal so it only sees 12V.
Quote from: danielzink on August 17, 2008, 08:15:01 PM
I'm in a bit of a quandry here.....
I really want to build this pedal (as well I probably will) - my problem is this:
My pedalboard is run by 2 Voodoo Labs Pedal Power II's - I have the option of 9v or 18v....if I want 12v I'll have to add a wall wart to the operation somewhere - not my best option.
Is there a way to run 18v into the circuit but "resistor" it down so it only sees 12v input ?
Thanks, Dan
Dan, you can also build one running at 9v - 12au7 seem to work good even at 9v at the heaters, else I'd suggest you to get a 9au7, which is the same tube accepting 9v as heater...You can get one dirt cheap thru the bay (as usual...)
I got one at €4 shipping included, go figure...I'd suggest you also to put a regulator, in that case it'llbe a 7809.
Quote from: frequencycentral on August 17, 2008, 08:09:54 PM
FYI, I am able to run two 12AU or two 6111 from my 12 volt / 500ma wallwart with ease.
Going to bed now - it's 1am her in the UK!
Me too, no problem with 500mA
Going to bed now - it's almost 3 am here in the Italy!
Quote from: Renegadrian on August 17, 2008, 08:49:31 PM
Quote from: danielzink on August 17, 2008, 08:15:01 PM
I'm in a bit of a quandry here.....
I really want to build this pedal (as well I probably will) - my problem is this:
My pedalboard is run by 2 Voodoo Labs Pedal Power II's - I have the option of 9v or 18v....if I want 12v I'll have to add a wall wart to the operation somewhere - not my best option.
Is there a way to run 18v into the circuit but "resistor" it down so it only sees 12v input ?
Thanks, Dan
Dan, you can also build one running at 9v - 12au7 seem to work good even at 9v at the heaters, else I'd suggest you to get a 9au7, which is the same tube accepting 9v as heater...You can get one dirt cheap thru the bay (as usual...)
I got one at €4 shipping included, go figure...I'd suggest you also to put a regulator, in that case it'llbe a 7809.
well....yeah.....I already bought my 6111's ;)
Dan
I haven't utilized a 7812 yet - but - from doing a quick search - it looks pretty easy.
Get a 7812 with proper output voltage. 7812's have 3 legs 'eh ? 18v into one leg, gnd into the other and 12v out of the other ?
Dan
Yep, and ground one leg.
Make sure you get the right "legs" though.
I tried going through all the posts and such, but there's a little bit of confusion on my part, so please excuse if I'm asking something already answered. So this pedal acts like a booster, and not like a distortion? I understand there won't be a lot of gain, but will it add some colour to my tone and just a bit of crunch?
And also, if I build it stock will it sound decent?
Thanks a lot!
Quote from: liddokun on August 18, 2008, 12:47:00 AM
And also, if I build it stock will it sound decent?
Yes. Perhaps a little dark.
It's not an entirely clean boost, even with the gain turned right down. The gain control increases dirt and volume.
Quote from: kurtlives on August 17, 2008, 07:46:25 PM
Threw in a battery and it works... yeah!
There was a lot of gum though...it stopped when I touched a ground point though, so I gotta figure that one out.
Did this not work because the power supply could supply enough current?
I don't know If you have solved your problem.
But it seems to me, that there is something wrong with your wiring.
Because there is no supply at all on your measurements.
Just try to connect the supply again and measure the incoming power on the power connector.
If this is good, then measure one side of 220K and so on.
I Hope you will find the problem
Quote from: liddokun on August 18, 2008, 12:47:00 AM
I tried going through all the posts and such, but there's a little bit of confusion on my part, so please excuse if I'm asking something already answered. So this pedal acts like a booster, and not like a distortion? I understand there won't be a lot of gain, but will it add some colour to my tone and just a bit of crunch?
And also, if I build it stock will it sound decent?
Thanks a lot!
I would say this circuit is definately an overdrive/distortion - and yes, a very decent sound.
As for cleaner boost, I have found the more resistance between you put between V1A pin 3 (the cathode) and earth, the cleaner the sound. I use a 100K gain pot instead of 50K for VR1, cleans up nicely.
There are a number of other mods people have suggested to clean up the sound and brighten it a little -
andrew_k is right, it is a little dark. I trawled this thread a while ago and got together all the mods. I've posted them before, but here they are again:
Possible improvement, depending on context:
"I note that the original schematic and layout specify that the triode at pins 1-3 be used for the voltage gain stage, and 6-8 for the follower.
This isn't usually the best way to do it with a 12A*7. With battery power or regulated DC going through the heaters, it doesn't matter which triode you use in which position, but if you're using AC or less-than-pristine DC, the triode at pins 6-8 will be quieter, due to the location of the heater pins on the tube. (You can find mention of this in the data sheets on many 12A*7 series tubes.)"
"I lower the coupling cap between stages for less bass."
"For lowering bass, you could try lowering the value of either the input cap, or the coupling cap between the two tube stages."
"I am bypassing the Valvecaster gain pot with a 2.2nf cap. This helps maintain some brightness when the VC gain is turned down. For the input cap on the Valvecaster I am using a combination of caps to give me 2.7nf. This helps tighten up the bottom end."
"To tame the gain I would lower R2 and R3. 220k and 100k seem pretty high for a low voltage circuit. Even in a regular high voltage amp the normal value is just 100k. So maybe cut them in half."
"if you bring down that 220k to 100k it will def lower the gain a bit. I built mine with both plate r's at 100k."
"A 1M gain pot allows massive, saturated gain. A little mushy in the bass frequencies, but pretty cool. I'm considering putting a "more" switch in, whereby it adds a resistor in series to the regular gain pot."
"Adding resistance to the plate resistors(R1 and R2) will increase gain. Adding resisitance to VR1, in series with the gain pot, will decrease gain."
"guitarx: replace the 100k resistor with 47k. Replace the 220k resistor with 100k. Beautiful cleans."
"To fellow Valvecaster experimenters -- I've currently got this circuit on a breadboard, switching out everything and I have some items of interest to report, especially for those looking for more gain.
The nicest clean sound I've found so far, is with the following mods:
R2 = 100k
R3 = 47k
C1 = 0.1uf
Remove C4 and VR2"
"Finally received that 7812 - mounted with the 100uF filter cap on the dc jack - hiss is just a memory...
put a 100uF cap across the DC jack (positive leg to positive rail, neg. leg to neg. rail), then, instead of connecting the positive rail directly to the circuit, connect it to the regulator's pin1, ground to pin2, and the circuit to pin3. Then screw it on the enclosure. It is a 7812."
Tried my Valvecaster with a LM7812 and now it works with a power supply!
It dosent seem regulated at all though...not sure if its working (I think this because the voltage is not 12V and there is a bit of added hum).
Also my gain knob did seem be to functioning....now it does nothing.
Dismantle it - build it again, even with the vero layout someone made... :icon_redface:
Why do you want everyone to use your layout?
I used it anyways...
Well, I'm so proud of it... :icon_cool:
Obviously I won't force anyone using it, but I'm glad someone did it and had good results...
Back to your circuit, well...I dunno...You say you got voltage but how's the sound? And the gain won't work...
Did you triple check every connection???
It sounds pretty good... Has more gain than I expected (even though I cant tweak the gain)
I saw a post somewhere in this thread that mentioned 150ma to run the pedal. Can anyone verify this ? I'm going to run my pedal with a PPII and it'll only make 200ma max with 18v Y cord (according to Voodoo Labs) - so I'm within spec - I just want to make sure.
Dan
Quote from: danielzink on August 18, 2008, 09:21:33 PM
I saw a post somewhere in this thread that mentioned 150ma to run the pedal. Can anyone verify this ? I'm going to run my pedal with a PPII and it'll only make 200ma max with 18v Y cord (according to Voodoo Labs) - so I'm within spec - I just want to make sure.
Dan
Mine was drawing 120mA yesterday.
Quote from: kurtlives on August 18, 2008, 09:28:50 PM
Quote from: danielzink on August 18, 2008, 09:21:33 PM
I saw a post somewhere in this thread that mentioned 150ma to run the pedal. Can anyone verify this ? I'm going to run my pedal with a PPII and it'll only make 200ma max with 18v Y cord (according to Voodoo Labs) - so I'm within spec - I just want to make sure.
Dan
Mine was drawing 120mA yesterday.
bee-yoo-tee-full
Thanks !
Dan
[/quote]
"A 1M gain pot allows massive, saturated gain. A little mushy in the bass frequencies, but pretty cool. I'm considering putting a "more" switch in, whereby it adds a resistor in series to the regular gain pot."
[/quote]
Think I could toss in a 1m gain pot but change the input cap or coupling cap between the tube stages to tame the mushiness? Or can I just up the value of the gain pot, but not to 1M, maybe something a bit less? I have a 500K reverse log pot. Would that work in increasing usable gain/saturated distorted sound?
Quote from: kurtlives on August 18, 2008, 09:28:50 PM
Quote from: danielzink on August 18, 2008, 09:21:33 PM
I saw a post somewhere in this thread that mentioned 150ma to run the pedal. Can anyone verify this ? I'm going to run my pedal with a PPII and it'll only make 200ma max with 18v Y cord (according to Voodoo Labs) - so I'm within spec - I just want to make sure.
Dan
Mine was drawing 120mA yesterday.
I also found an interesting tone change when I changed my 9V regulated adapter from a 200mA to a 300mA.
The tone was much more gritty with the 200mA but not as dynamic. The 300mA is a more mild OD tone, a little brighter and has a little more dynamics. I'll try to make a demo as soon as I get some time.
-bK
Gain is at the maximum when resistance is 0.
So going with a bigger value pot isnt really doing...just giving more "clean headroom" until you hit cutoff and the bias goes.
Higher value pots will also make it harder to dial in the right amount of gain for you.
Just picked up 8 7AU7 valves for $2.50 each (7v heater version of 12AU7) to try with this circuit, the Vibracaster and Pepper Shredder. With an LM317 regulator I'm hoping I can power them off 9v, as the LM317 spec states a 1.2v loss
Just another valve to look out for cheap deals on.
I'm a little confused by this circuit's gain control. Reports are that gain is at maximum when resistance is at 0. But what this control does (or should do) is alter the bias. Center bias for this stage would probably be around 5k somewhere. Increasing the resistance would push the stage toward cut off, sort of like lowering the forward voltage of a diode clipper. Eventually, the entire negative side of the waveform would be gone. In the other direction, decreasing resistance would warm bias the stage, heading toward 0 Grid volts, eventually making the triode a half wave rectifier. This is what it looks like is happening with the second stage. It could be grid leak biased I suppose, but 470k doesn't seem enough to give a proper grid bias (probably more like 10M!)
Can anyone offer some theoretical insight as to why this operates the way it does?
Quote from: kurtlives on August 17, 2008, 06:24:34 PM
I am using an unregulated 12V DC power supply...It can shoot upwards of 16.5V DC.
I'm a little late on this, but I'm pretty sure this thing needs regulated voltage. I tried mine with an unregulated 12V power supply and it didn't work hardly at all. Mostly just made noise; a little signal coming through. But when I use a boss-style regulated 9v power supply, it works fine.
The first I made was without the regulator - it worked but hiss was a nightmare - then a 7812 woked me up and hiss was gone...
Like FrequencyCentral's summary, I've just finished consolidating some notes and diagrams from this fine forum thread. I was getting tired of opening and closing diagrams so decided to consolidate everything to one document and wanted to consolidate the mods for this pedal.
Just thought other folks here may be able to use this rather than browse thru 34+ pages of this thread (which is excellent reading by the way) to find tips and mods. Maybe it will inspire others to build one or two... or three.. or... :D
http://www.aronnelson.com/DIYFiles/up/12AU7-6111_Valve_Caster_Summary.pdf
-bK
Quote from: tranceracer on August 21, 2008, 01:16:30 AM
I've just finished consolidating some notes and diagrams from this fine forum thread. I was getting tired of opening and closing diagrams so decided to consolidate everything to one document and wanted to consolidate the mods for this pedal.http://www.aronnelson.com/DIYFiles/up/12AU7-6111_Valve_Caster_Summary.pdf
tranceracer, that is a superb piece of work!!
You may like to add the information from this thread: http://www.diystompboxes.com/smfforum/index.php?topic=70212.0
Quote from: frequencycentral on August 20, 2008, 08:58:45 PM
If you're reading this you'll already know that I'm obsessed with 6111 submini dual triodes!
I'm looking at ways of powering a single 6111 heater from a 12 volt supply. The 6111 requires 6.3 volts (300ma) ideally, but 6 volts should be fine.
The only example I have to go on is Dano12's way of powering the Subcaster (http://i210.photobucket.com/albums/bb292/frequencycentral/SubCaster-1.gif), which uses an LM317 and associated parts.
I'm thinking a simple resistor voltage divider would do the trick a little more elegantly.
Just looking at the math:
6 volts divided by 300mA = 20 Ohm
6 volts multiplied by 300mA = 1.8 Watts.
So - I'm looking at a voltage divider using two 20 ohm/1.8 watt resistors. Is this correct?
Next: I only have 10 ohm/3 watt in my parts bin. Am I right in assuming two of these are more than enough?
Finally: Most voltage dividers I've seen for 'vref' purposes include an electro cap (say 10uf) between the vref and earth, should I include one in my voltage divider?
Thanks!
Quote from: R.G. on August 20, 2008, 09:20:16 PM
The tubes' heaters allow 300ma to pass when there is 6.3V across them, and they are resistive. That means, as you properly compute, that the resistance of a heater is 6.3V/0.3A = 21 ohms. If you have 12Vdc and want to drive 300ma into you heaters, you can do that easily enough without using a voltage divider by putting a resistor in series with the heater. The resistor is R = V/I = (12-6.3)/0.3 = 5.7/0.3 = 19 ohms. It would dissipate 5.7*0.3 = 1.7W and you'd need to use a 3W resistor to keep it from runnig at about 200C surface temp.
A 20/20 divider will not give you what you think. A divider composed of 20 ohms / 20 Ohms from 12V will gie you 6V only when there is no load on the 'Y"s. This produces 6C only when it's not loaded.
Quote from: frequencycentral on August 21, 2008, 01:47:07 AM
Thank you again R.G., that's just great! Amazingly simple solution. 8)
Summary: Running a 6111 submini tube heater at 6.3 volts from a 12 volt DC supply.Put a
19 ohms 3 watt resistor in series with the heater.
So - no need for the LM317/220 ohm resistor/1K trimpot.EDIT: I tried it - it works. I had two 10 ohm 3 watt resistors in my parts bin which I scavenged from an old T.V. set. With 5% tolerance, they add up to 19 ohm in series. They get HOT! But then so does the tube, or an LM317 for that matter! They actually get too hot to touch for more than a few seconds - much hotter than the tube.
I've benn obsessing over this pedal also......
One thing I'd like to add - I contacted Jimmy H re: the tone stack PCB. It wasn't making sense to me how it was laid out vs his Pepper Shredder PCB on page (25 ? 26?) which has -right on the PCB TS-A (tone stack in) and TS-B (tone stack out).
Here's his reply:
I see what you mean (and it was in Dutch).
And you should discard the volume pot in the layout of the tonestack (because there is already a volume pot on the shredder)
So Connect A with in
B with middle tap of the treble pot
Aarde with Ground from the pepper shredder.
I also have used this layout for an amplifier of mine, that's why the volume pot is on the layout of the tonestack.
HTH, Dan
Thanks Tranceracer......I'm looking to build this pedal.....must get parts.
Rick, thanks for the additional tips! I've updated the .pdf. I've also added links to the diagrams to the authors in the thread.
Quote from: ehofherr on August 21, 2008, 12:18:49 PM
Thanks Tranceracer......I'm looking to build this pedal.....must get parts.
No problemo! It's the great members of this forum who actually did all the work! :D I just consolidated it.
Enjoy!
-bK
Very small review:
I tried it out at an outdoor gig last weekend. I stomped all configurations I could think of and it ended up as a semi-clean lead pedal for songs like sweet Home Alabama. It could slightly overdrive my clean channel without the typical solid-state wimpness.
I tried boosting it with MXR, TS9, and CS-3 which all failed. It worked best alone as a clean channel boost.
I'll give it a try next weekend at another outdoor event but as for now it likely wont make my rig :icon_sad:
Quote from: FlyingZ on August 22, 2008, 11:57:46 AM
Very small review:
I tried it out at an outdoor gig last weekend. I stomped all configurations I could think of and it ended up as a semi-clean lead pedal for songs like sweet Home Alabama. It could slightly overdrive my clean channel without the typical solid-state wimpness.
I tried boosting it with MXR, TS9, and CS-3 which all failed. It worked best alone as a clean channel boost.
I'll give it a try next weekend at another outdoor event but as for now it likely wont make my rig :icon_sad:
Yea I use it by itself to overdrive my amp sim. It doesn't play well with my other pedals either. Right now it's the main pedal for the tone I'm looking for.
Here are some sound clips:
Valve Caster boost kicks in at about T-24 seconds. Recording setup: Humbucker (bridge position), valve caster (stock setup), amp simulator, recording rig.
http://www.aronnelson.com/gallery/main.php/v/bK-diystompbox/ValveCasterRiff+001.mp3.html
TranceRiff using ValveCaster Pedal. Valve Caster kicks in at T-23 seconds.
http://www.aronnelson.com/gallery/main.php/v/bK-diystompbox/TranceRiff+003.mp3.html
Great clips, I love the way the ValveCaster doesn't change the original tone like I'm discovering so many DIY projects do. I really hope to find another good one soon :P
Two breadboard projects (BluesBreaker and CK721 ToneBender) to finish testing and I will submit a ValveCaster clip.
Hi guys, first message here..
I read all this thread many times, there are a lot of great tube projects, and I decided to make my own.
I'd like to thank you for gathering all the "mods" on one post, that is very usefull...
The idea is to make an overdrive pedal out of a Twincaster, and be able to go from barely clean sounds to huge amounts of OD gain (using a 12AY7 tube, which someone told me it was more adapted for OD).
I know that I'm gonna have to breadboard a lot before getting satisfied, but the modslist should help a lot..
Hello and welcome aboard - I am sure your work will be appreciated. Looking forward to see your results!
Thank you Adriano, but I'm still a bit confused about something..
In the mods list, we have both version of the gain pot:
Quote"A 1M gain pot allows massive, saturated gain. A little mushy in the bass frequencies, but pretty cool. I'm considering putting a "more" switch in, whereby it adds a resistor in series to the regular gain pot."
Which means that the higher the pot value (and thereby the cathode resistor value), the higher the gain.
But there's also this:
Quote"Adding resistance to the plate resistors(R1 and R2) will increase gain. Adding resisitance to VR1, in series with the gain pot, will decrease gain."
Which one is the right one? ??? ???
Quote from: Franky on August 26, 2008, 12:44:02 PM
Quote"A 1M gain pot allows massive, saturated gain. A little mushy in the bass frequencies, but pretty cool. I'm considering putting a "more" switch in, whereby it adds a resistor in series to the regular gain pot."
Quote"Adding resistance to the plate resistors(R1 and R2) will increase gain. Adding resisitance to VR1, in series with the gain pot, will decrease gain."
Which one is the right one? ??? ???
The first one is wrong - the triode is at its loudest with the cathode hooked directly to ground. I prefer a 100K gain pot, as this will increase clean headroom.
Everything in the second quote is correct.
Thank you Rick!
Okay, I planned my design using a "More Gain" switch, which would have done exactly the contrary as expected if I had followed the first quote's instructions.. ;D
Well, to get more gain the only solution would be to put a switch to increase the plate resistors? I thought about putting a 100k resistor in series with 2nd and 4th triodes' plate resistors (making a 200k equivalent plate resistor).
What do you think about it?
I also noticed that someone here used a 2.2nF bypass cap across the gain pot, to "keep some brightness" when the gain is down. Good idea too..
Quote from: Franky on August 26, 2008, 02:19:34 PM
Well, to get more gain the only solution would be to put a switch to increase the plate resistors?
..........or make ALL the plate resistors into pots for a multi knob
Evilcaster!!! :icon_mrgreen:
Wow, don't tempt me.. ;D ;D
Here's my schematic. So far, it's a beta version: (also available in PDF format, here (http://frankyfuzzfire.free.fr/DIY/LAMPES/LowVoltage/TwinPeaksSchematic.pdf))
(http://frankyfuzzfire.free.fr/DIY/LAMPES/LowVoltage/TwinPeaksSchematic.png)
There is also one thing not to forget: pots don't like the DC current. It would be better for their lifetime to feed them AC signal, and mount them as volume pots. Between 2 VC for example, or as in old Marshall preamps, after the first triode.
Seems a great circuit...Did you build it yet or it's just a schem?
Looks cool :)
I'd change the classic/more gain switch so that the 2 resistors (R4, R5) are permanently connected and use the switch to short one of them out. The way you've got it when you flip the switch you'll momentarily break the connection to the plates which might lead to pops and other nasty noises.
@ Adriano: No it's only a schemo, I don't have the parts yet, but when it's the case, I spend some time on the breadboard to make it sound as I want..
@ Slacker: damn you're right, I thought about popping, but this solution was something I didn't think about.. Thank you!
I still don't know whether I put some caps across the gain pots or not.. Anyway there are a lot of values possible, 2.2nF was written on the summup..
Edit: it's updated.. ;)
On my dual Valve Caster I am using a dual gang 100K B pot. Controls both gains..
that's incredible all these little tubes can make.. (speaking about the Vibrocaster), I'm sure it's possible to design a tube wah.. A Wahlvecaster?
You can't think of anything that R.G. hasn't done.
http://geofex.com/article_folders/tube-wah/tube-wah.htm (http://geofex.com/article_folders/tube-wah/tube-wah.htm)
Here is my plain 12v ValveCaster clip:
http://www.aronnelson.com/gallery/main.php/v/FlyingZ/ValveCaster.mp3.html?g2
Very nice clips! I like how you have your ValveCaster sounds with different tones. I think I'll have to redo my samples! ;)
-bK
Wow, I started reading that about three hours ago. Read, digested and puked it all back up again. Man that's a lot of good stuff. Around page 27, I just started scrolling through to look at the pictures because some of them are very lovely. I went to the layout section of this site to look for some of the board stuff, but only could find dano's original. I'm not sure if there is a verified section of layouts, mods, parts and stuff, but if there isn't, that could be a good thing to have.
I also think I'm going to have to try and put one of these together. I really liked the one that used two 12au7 tubes. I was thinking about making them more kind of like two pedals in one instead of one pedal. One footswitch would turn one on and another switch to activiate the next tube for more gain. I would like to only have 2 gains, one volume and one tone. Is that possible with this kind of setup? Then I also read in there somewhere that having a booster in there is a good idea too. So where is the best place for that to go? I was thinking of putting in a stratoblaster because the LB1 or 2 were said to be too muddy. Maybe even a stratoblaster before and after the circuit? Sheesh.
Also, I've only dealt with building a guytronix tube amp and a bunch of pedals, but they dont use 12v adapters. Where can I get one of these that good but also not very expensive, as I am poor.
Thanks :icon_mrgreen: and sorry if this was all discussed. My mind is fried from the rest of this thread to comprehend the last few pages.
quote author=mth5044
I went to the layout section of this site to look for some of the board stuff, but only could find dano's original. I'm not sure if there is a verified section of layouts, mods, parts and stuff, but if there isn't, that could be a good thing to have.
STRANGE, DID YOU SEARCH FOR VALVECASTER? TYPE IT, YOU WILL FIND MY VERO LAYOUTS. OR YOU CAN SEARCH MY FOLDER IT'S AT THE LAST PAGES.
I also think I'm going to have to try and put one of these together. I really liked the one that used two 12au7 tubes. I was thinking about making them more kind of like two pedals in one instead of one pedal. One footswitch would turn one on and another switch to activiate the next tube for more gain. I would like to only have 2 gains, one volume and one tone. Is that possible with this kind of setup? Then I also read in there somewhere that having a booster in there is a good idea too. So where is the best place for that to go? I was thinking of putting in a stratoblaster because the LB1 or 2 were said to be too muddy. Maybe even a stratoblaster before and after the circuit? Sheesh.
NOT A CRAZY IDEA, THAT COULD BE DONE...AND YES A BOOSTER BEFORE THE TUBE COULD SPICE THINGS UP...I'D SAY TILLMAN OR STRATOBLASTER TOO...BUT AS A BOOSTER IS SO EASY TO BUILD (I HAVE SEVERAL JUST TO TRY THEM...) I'D SAY BUILD THE ONES YOU WANT AND TRY THEM ALL...
Also, I've only dealt with building a guytronix tube amp and a bunch of pedals, but they dont use 12v adapters. Where can I get one of these that good but also not very expensive, as I am poor.
I USE A €5 ONE AND A €7 ONE - CHINESE MADE - THEY DO THE JOB AND WON'T BREAK FINANCES...
Thanks :icon_mrgreen: and sorry if this was all discussed. My mind is fried from the rest of this thread to comprehend the last few pages.
I BELIEVE YOU'LL BE SAYIN' "HOW THE HELL CAN SUCH A SIMPLE CIRCUIT BRING OUT THESE SOUNDS!!!!" - ACTUALLY I DID...
Quote from: mth5044 on September 04, 2008, 09:28:49 PM
Wow, I started reading that about three hours ago. Read, digested and puked it all back up again. Man that's a lot of good stuff. Around page 27, I just started scrolling through to look at the pictures because some of them are very lovely. I went to the layout section of this site to look for some of the board stuff, but only could find dano's original. I'm not sure if there is a verified section of layouts, mods, parts and stuff, but if there isn't, that could be a good thing to have.
I also think I'm going to have to try and put one of these together. I really liked the one that used two 12au7 tubes. I was thinking about making them more kind of like two pedals in one instead of one pedal. One footswitch would turn one on and another switch to activiate the next tube for more gain. I would like to only have 2 gains, one volume and one tone. Is that possible with this kind of setup? Then I also read in there somewhere that having a booster in there is a good idea too. So where is the best place for that to go? I was thinking of putting in a stratoblaster because the LB1 or 2 were said to be too muddy. Maybe even a stratoblaster before and after the circuit? Sheesh.
Also, I've only dealt with building a guytronix tube amp and a bunch of pedals, but they dont use 12v adapters. Where can I get one of these that good but also not very expensive, as I am poor.
Thanks :icon_mrgreen: and sorry if this was all discussed. My mind is fried from the rest of this thread to comprehend the last few pages.
Here's a summary of some of the topics that inspired me to build this.
http://www.aronnelson.com/DIYFiles/up/12AU7-6111_Valve_Caster_Summary.pdf
Renegadrian's vero has been tested and known to work. I also posted a PCB (but IMHO, a lot of extra work for such a small ckt. :icon_wink:)
Send us pics of your 'caster when you're done. :)
Quote from: tranceracer on September 05, 2008, 01:47:20 AM
Quote from: mth5044 on September 04, 2008, 09:28:49 PM
Wow, I started reading that about three hours ago. Read, digested and puked it all back up again. Man that's a lot of good stuff. Around page 27, I just started scrolling through to look at the pictures because some of them are very lovely. I went to the layout section of this site to look for some of the board stuff, but only could find dano's original. I'm not sure if there is a verified section of layouts, mods, parts and stuff, but if there isn't, that could be a good thing to have.
I also think I'm going to have to try and put one of these together. I really liked the one that used two 12au7 tubes. I was thinking about making them more kind of like two pedals in one instead of one pedal. One footswitch would turn one on and another switch to activiate the next tube for more gain. I would like to only have 2 gains, one volume and one tone. Is that possible with this kind of setup? Then I also read in there somewhere that having a booster in there is a good idea too. So where is the best place for that to go? I was thinking of putting in a stratoblaster because the LB1 or 2 were said to be too muddy. Maybe even a stratoblaster before and after the circuit? Sheesh.
Also, I've only dealt with building a guytronix tube amp and a bunch of pedals, but they dont use 12v adapters. Where can I get one of these that good but also not very expensive, as I am poor.
Thanks :icon_mrgreen: and sorry if this was all discussed. My mind is fried from the rest of this thread to comprehend the last few pages.
Here's a summary of some of the topics that inspired me to build this.
http://www.aronnelson.com/DIYFiles/up/12AU7-6111_Valve_Caster_Summary.pdf
Renegadrian's vero has been tested and known to work. I also posted a PCB (but IMHO, a lot of extra work for such a small ckt. :icon_wink:)
Send us pics of your 'caster when you're done. :)
In that summary on page 4 the Dual Valve Casters schematic 3. triode still missing a gridleak resistor.
http://www.diystompboxes.com/smfforum/index.php?topic=68759.0
Ah that .pdf file is wonderful. Thanks for answering everything to promptly.
I think I'm going to go with this twincaster schematic
http://www.aronnelson.com/gallery/main.php/v/Renegadrian/Twincaster+rev+0_11.jpg.html
with the R1 pulldown on the second half, seeing as that one fellow had quite a bit of trouble. I am also thinking about adding a switch to cut in and out the second tube. What if I take a SPDT on/on switch, wire C3a to the middle lug, a wire on another lug going V2a where it usually connects then on the other lug, a wire between C3b and C4? I believe that would make it so in one switch direction it would make it like the regular valvecaster then the other way it would be a twincaster.
As for the booster, I'm a poor college student so ordering and building a bunch of different boosters will have to loose out to getting more grocerys :'( So of the people that have put boosters before, what ones sound best? I play a strat and LP into my 2watt gilmour jr (which is a bit darker to begin with) with whatever effects inbetween.
Also, would it be a good idea to put an on/off switch in the back or something to get the tubes to warm up? Kind of like a standby?
Final question of the post - That fixed voltage regulator, is it necessary? It seems that adding that and then a heatsink would take up a lot of room (even though I'm planning on building it in a large enclosure anyway).
Quote from: mth5044 on September 05, 2008, 10:19:48 AM
A. Also, would it be a good idea to put an on/off switch in the back or something to get the tubes to warm up? Kind of like a standby?
B. Final question of the post - That fixed voltage regulator, is it necessary? It seems that adding that and then a heatsink would take up a lot of room (even though I'm planning on building it in a large enclosure anyway).
A. I don't think it is necessary, no one did it anyway.
B. It's only necessary if you have a bad regulated and filtered power supply.
I used an old printer (switching)power supply.
success with your build! ;)
I built mine. But i dont have a propper powersupply. I found one but output is 18V. How to make it work with 18V What has to be added?
I actually built Pepper Shredder, but its the same deal.
Quote from: served on September 06, 2008, 09:30:45 AM
I built mine. But i dont have a propper powersupply. I found one but output is 18V. How to make it work with 18V What has to be added?
I actually built Pepper Shredder, but its the same deal.
Use a 7812 like on the Twincaster circuit on the previous page of this thread to regulate your 18 volt input down to 12 volts. The 7812 has a maximum input voltage of 35 volts, so it should be fine
Quote from: frequencycentral on September 06, 2008, 09:52:31 AM
Quote from: served on September 06, 2008, 09:30:45 AM
I built mine. But i dont have a propper powersupply. I found one but output is 18V. How to make it work with 18V What has to be added?
I actually built Pepper Shredder, but its the same deal.
Use a 7812 like on the Twincaster circuit on the previous page of this thread to regulate your 18 volt input down to 12 volts. The 7812 has a maximum input voltage of 35 volts, so it should be fine
So if I put a stratoblaster infront of it, which runs on 9 volts, should I use the 7812 infront of that to take it down the 12v adapter to 9v? Or can the stratoblaster run on 12v?
Here is the schem/parts I am using for it http://www.generalguitargadgets.com/index.php?option=com_content&task=view&id=64&Itemid=26
I know, I'm sorry this has nothing to do with the original purpose of the thread. I'm still in the process or drawing up how to breadboard will look, so hopefully you all can check that out for me too :icon_mrgreen:
Quote from: mth5044 on September 06, 2008, 01:04:46 PM
Quote from: frequencycentral on September 06, 2008, 09:52:31 AM
Quote from: served on September 06, 2008, 09:30:45 AM
I built mine. But i dont have a propper powersupply. I found one but output is 18V. How to make it work with 18V What has to be added?
I actually built Pepper Shredder, but its the same deal.
Use a 7812 like on the Twincaster circuit on the previous page of this thread to regulate your 18 volt input down to 12 volts. The 7812 has a maximum input voltage of 35 volts, so it should be fine
So if I put a stratoblaster infront of it, which runs on 9 volts, should I use the 7812 infront of that to take it down the 12v adapter to 9v? Or can the stratoblaster run on 12v?
Here is the schem/parts I am using for it http://www.generalguitargadgets.com/index.php?option=com_content&task=view&id=64&Itemid=26
I know, I'm sorry this has nothing to do with the original purpose of the thread. I'm still in the process or drawing up how to breadboard will look, so hopefully you all can check that out for me too :icon_mrgreen:
I would guess the Stratoblaster should run on 12 volts, but as its a JFET you may need to re-bias it for 12 volts by changing R2. I think the process would be to build and test the SB at 9 volts, measure the voltage at the JFET's 'Drain', power it up at 12 volts and use a trimpot to replicate the voltage at the JET's 'Drain'.
Alternatively, I built a LPB into my second Valvecaster, and didn't do anything at all about the voltage change! So - it might work out just fine without doing a thing to it - just give a little more gain maybe........
Quote from: snap on September 05, 2008, 02:54:36 AM
In that summary on page 4 the Dual Valve Casters schematic 3. triode still missing a gridleak resistor.
http://www.diystompboxes.com/smfforum/index.php?topic=68759.0
Are you referring to this dialogue between ambulancevoice and Renegadrian?
http://www.diystompboxes.com/smfforum/index.php?topic=68759.msg550659#msg550659
I'll add this note to the summary.
Thanks!
-bK
Quote from: tranceracer on September 06, 2008, 01:57:57 PM
Quote from: snap on September 05, 2008, 02:54:36 AM
In that summary on page 4 the Dual Valve Casters schematic 3. triode still missing a gridleak resistor.
http://www.diystompboxes.com/smfforum/index.php?topic=68759.0
Are you referring to this dialogue between ambulancevoice and Renegadrian?
http://www.diystompboxes.com/smfforum/index.php?topic=68759.msg550659#msg550659
I'll add this note to the summary.
Thanks!
-bK
http://www.diystompboxes.com/smfforum/index.php?topic=68759.msg550722#msg550722
similar is true for FET gates: don`t let them float.
(http://i246.photobucket.com/albums/gg114/mth5044/TSschem.jpg)
I added a DPDT switch in there between C3 and the new R1. Once you cut out the second tube, it should be exactly like a valvecaster right? Am I missing anything big here? Is there going to be an awful pop or something with the switch is engaged?
I'm going to add in a two color LED to the other side of the DPDT to show what tubes are being used. I found a 3 color LED while searching for the two color one. Is it bad if I want to build something just to use a three color LED :icon_mrgreen:
Put the final connection of the switch before the last coupling "blocking" cap (C3).
You mean the one right before the tone pot setup? If I did that, would that make 2 C3's in a row?
yes, it will pop, and bytheway there are already 2 C3`s in that schematic ?
The names are not that important, but BTW yeah, it's a little bit confusing..
To put both C3 in series by switching will definitely pop out..
Anyway, are you sure of that wiring for your 1M R1(bis) resistor, right after the switch? Isn't that supposed to go from the plate to the ground?
Good idea about the LEDs, I'm planning to put some RGB automatically color changing in my tubes sockets.. Cool effect.. :icon_wink:
(http://i246.photobucket.com/albums/gg114/mth5044/TSschem-1.jpg)
based on my inferior knowledge of the recomendations, here is an updated schematic. I added a's and b's so hopefully it wont be as confusing, changed R1b and put the switch before C3b, although that doesnt make too much sense to me.
If there is no way to solve the popping part, I guess ill just build two valvecasters but use dual pots for the tone and volume. Pretty much the same thing I guess.
Quote from: frequencycentral on September 06, 2008, 01:16:54 PM
Quote from: mth5044 on September 06, 2008, 01:04:46 PM
So if I put a stratoblaster infront of it, which runs on 9 volts, should I use the 7812 infront of that to take it down the 12v adapter to 9v? Or can the stratoblaster run on 12v?
Here is the schem/parts I am using for it http://www.generalguitargadgets.com/index.php?option=com_content&task=view&id=64&Itemid=26
I know, I'm sorry this has nothing to do with the original purpose of the thread. I'm still in the process or drawing up how to breadboard will look, so hopefully you all can check that out for me too :icon_mrgreen:
I would guess the Stratoblaster should run on 12 volts, but as its a JFET you may need to re-bias it for 12 volts by changing R2. I think the process would be to build and test the SB at 9 volts, measure the voltage at the JFET's 'Drain', power it up at 12 volts and use a trimpot to replicate the voltage at the JET's 'Drain'.
Alternatively, I built a LPB into my second Valvecaster, and didn't do anything at all about the voltage change! So - it might work out just fine without doing a thing to it - just give a little more gain maybe........
Either you could use a 9AU7 tube, which is the 9v version of the 12AU7...use a 7809 if you need a regulated v and run both fx at the standard 9v. I'd say 500mA or more as for the wall wart, try 300mA too but the more the better I believe.
for less popping, add another 1M from the righthandside of C3a to ground.
It might be best to uses a DPDT switch to isolate the second Valvecaster from the output.
I think I'm just going to do it so that there are technically two valvecasters in one box, rather then going for a switchable twincaster. So it will go stratobooster -> valvecaster which when turned on will take to to the switch for the second valvecaster, and when off will take it to the out. That way when I want to go from 2 valvecasters to none, I'll only have to hit one switch. Then the second valvcaster switch will go to the out also. Kind of like this (sorry about the huge picture, my photoshop skills are lacking):
(http://i246.photobucket.com/albums/gg114/mth5044/switching.jpg)
VC1 and VC2 are valvecaster 1 and 2 and the two left sides of both switches reserved for LED indicators. Should I ground the 2nd lug on the third horizontal row on the VC1 switch? Usually not grounding something screws me over so I thought I'd ask.
\I'm also debating if I want to go with the dualgang volume and tone pots or do seperate ones for each. I like the dual gang for the less clutter, but I'm one for versitility, so maybe combining using two volumes and tones at the same time would be cool, like combining different tones and volumes on the middle switch of a les paul. I think I've got a pretty good layout design too, just need to see if pedalpartsplus can drill holes for tube sockets :icon_rolleyes:
Thanks again for your help.
Hey. Im starting to build that circuit for fixed voltage. Is it wise to use one power supply and add two regulators to it? 12V and 9V? Is it wise to save some parts and put 7812 and 7809 parallel after 0.1uF and 470uF, but all that is after the regulator is independent, 7812 is with its own 3 caps to output and 7809 has its own?
I hope you ll understand what i mean.
I didn't get what you mean...Do you want it to be powered at 9v or 12v?
You have to use either 7809 or 7812, depending on the choice above...
Else I don't see the need of 2 regulators...
Ill build a powersupply for my pedals. All the transistor based pedals use 9V so i need it too. Guess it wont change anything if i put two 78xxs like i wanted. The point is, why do i have to waste 1x0.1uF and 1x470uF if i can keep thouse.
Quote from: snap on September 05, 2008, 02:54:36 AM
In that summary on page 4 the Dual Valve Casters schematic 3. triode still missing a gridleak resistor.
http://www.diystompboxes.com/smfforum/index.php?topic=68759.0
Revised summary:
http://www.aronnelson.com/DIYFiles/up/12AU7-6111_Valve_Caster_Summary_Rev002.pdf
Includes the 'caster's 2nd 1Meg Resistor and the schematic and discussions re: the switch mod.
Thanks! (:
-bK
Hmmm.... Ok - hi - long time lurker - very rare post-er....
Here's the kind of problem you LOVE:
"Model-builder with lousy parts and barely passable solder skills seeks help with HUM."
First, apologies if I missed something in the 38+ pages, I have tried to read it all thoroughly.
I'm just hoping for some general advice before I scrap this one and re-build from scratch.
Massive hum problem - but the circuit boosts and distorts freaking GREAT.
Built the 7812 power regulator.
Caught a an ungrounded lug on a pot - that fixed some of the hum.
Caught a silly mistake, when I used a NP cap for C3 (the DC blocking cap, correct?)
BUT - that didn't seem to fix the problem at all.
Tried 3 12AU7s, 12AV7, 12AT7
Also, have tried 6v 500ma, 9v 200ma, 9v 500ma, 12v 500ma - all wallwarts, all hum. Higher voltage = more hum.
And OF COURSE, those are all QUALITY parts (sarcasm here), from various telephones, answering machines, baby monitors etc.
Here is where it all went off the tracks - I initially had my stupid DC wiring backwards (CANNOT get my mind around a negative tip. Call me wet behind the ears, I don't mind) and so I'm wondering if I cooked something? The weird thing is, the circuit seems to work very well - just very very loud hum. Used to be as loud as the guitar signal, but the regulator and fixed grounding issue reduced the hum by about 50%
It's just on the verge of being usable now.
I'm not concerned about hiss, buzz, or any other noisy racket - just this loud HUM.
NOW - I'm getting about 4 VDC on the output! (surprised?)
So that means blocking cap (C3) and/or resistor (R3), right?! Or something else?
Could it be that every 1uF cap that I own (about 6, all salvage) doesn't work?
Could it be that my soldering skills demonstrate borderline dementia?
Did I mention the incredible quality of salvaged parts I'm using?
...actually, all but the 1uf were new parts... except the tube(s)... and the socket... and the jacks...
SO. Scrap it and start again (with newer parts) or is it salvagable?
Again, apologies if I shoulda started a new post or something, I do a LOT of reading, but not much posting. Prefer to keep my mouth shut when I don't know what I'm talking about.
Oh yeah, and btw everyone of you mofos completely rocks, this forum has been LIFE CHANGING for me. If it disappeared tomorrow I'd wander the streets aimlessly for weeks.
Quote from: c.wright on September 09, 2008, 03:36:44 PM
Hmmm.... Ok - hi - long time lurker - very rare post-er....
Here's the kind of problem you LOVE:
"Model-builder with lousy parts and barely passable solder skills seeks help with HUM."
First, apologies if I missed something in the 38+ pages, I have tried to read it all thoroughly.
I'm just hoping for some general advice before I scrap this one and re-build from scratch.
Massive hum problem - but the circuit boosts and distorts freaking GREAT.
Built the 7812 power regulator.
Caught a an ungrounded lug on a pot - that fixed some of the hum.
Caught a silly mistake, when I used a NP cap for C3 (the DC blocking cap, correct?)
BUT - that didn't seem to fix the problem at all.
Tried 3 12AU7s, 12AV7, 12AT7
Also, have tried 6v 500ma, 9v 200ma, 9v 500ma, 12v 500ma - all wallwarts, all hum. Higher voltage = more hum.
And OF COURSE, those are all QUALITY parts (sarcasm here), from various telephones, answering machines, baby monitors etc.
Here is where it all went off the tracks - I initially had my stupid DC wiring backwards (CANNOT get my mind around a negative tip. Call me wet behind the ears, I don't mind) and so I'm wondering if I cooked something? The weird thing is, the circuit seems to work very well - just very very loud hum. Used to be as loud as the guitar signal, but the regulator and fixed grounding issue reduced the hum by about 50%
It's just on the verge of being usable now.
I'm not concerned about hiss, buzz, or any other noisy racket - just this loud HUM.
NOW - I'm getting about 4 VDC on the output! (surprised?)
So that means blocking cap (C3) and/or resistor (R3), right?! Or something else?
Could it be that every 1uF cap that I own (about 6, all salvage) doesn't work?
Could it be that my soldering skills demonstrate borderline dementia?
Did I mention the incredible quality of salvaged parts I'm using?
...actually, all but the 1uf were new parts... except the tube(s)... and the socket... and the jacks...
SO. Scrap it and start again (with newer parts) or is it salvagable?
Again, apologies if I shoulda started a new post or something, I do a LOT of reading, but not much posting. Prefer to keep my mouth shut when I don't know what I'm talking about.
Oh yeah, and btw everyone of you mofos completely rocks, this forum has been LIFE CHANGING for me. If it disappeared tomorrow I'd wander the streets aimlessly for weeks.
Hi Chris! Test your voltages and post them here.
Here's mine, running at 12 volts:
Pin 1: 3.02v
Pin 2: -0.518v
Pin 3: 0.00v
Pin 4: 0.00v
Pin 5: 11.97v
Pin 6: 8.21v
Pin 7: -1.285v
Pin 8: 0.00v
Pin 9: 5.91v
Quote from: c.wright on September 09, 2008, 03:36:44 PM
Oh yeah, and btw everyone of you mofos completely rocks, this forum has been LIFE CHANGING for me. If it disappeared tomorrow I'd wander the streets aimlessly for weeks.
we'd say it's better for you to stay, but even if you don't you gotta have your valvy up and running silently...
C3 (1µF) can be P or NP, I used them both...
WOW. You guys are FAST.
OK, here's my numbers from 2 different wallwarts:
12v 500ma (meters at 17.5v)
1. 11.65
2. -0.491
3. 0
4. 0
5. 13.42
6. 8.96
7. -0.534
8. 0
9v 300ma (meters at 15v)
1. 9.86
2. -0.335
3. 0
4. 0
5. 11.14
6. 8.02
7. -0.330
8. 0
(pesky numbers - in my perfect world, all science is based on COLORS...)
Soooooo.... since my pin 1 is off the charts, am I to assume that my 220K (R2) is cooked, shorted, cold-jointed or otherwise?
Man, i was all proud thinking i'd troubleshot that C3 and now you blow it for me Renegadrian!! :icon_redface:
I'da thought a blocking cap would need to only let stuff go one-way?
Welp, showing my ignorance here.
I've built about 40 projects, and I'd say my hit/miss ratio is a good 60/40!
- I can build models & puzzles real good, but I'm only so-so on the theory.
Thanks again for the quick replies, and thanks in advance for the help!
Quote from: c.wright on September 09, 2008, 05:37:10 PM
12v 500ma (meters at 17.5v)
1. 11.65
2. -0.491
3. 0
4. 0
5. 13.42
6. 8.96
7. -0.534
8. 0
Soooooo.... since my pin 1 is off the charts, am I to assume that my 220K (R2) is cooked, shorted, cold-jointed or otherwise?
Thanks again for the quick replies, and thanks in advance for the help!
Yup, it's pin 1 that's the problem as you correctly identifed! Check the resistor with your meter for ohmage/continuity. And shorts, cold-joints or otherwise!
All the other voltages look good, but your 12 volts DC looks like its actually 13.42 volts, judging from pin 5. I think that may still be within the heater tolerance, but it would be worth you checking that out on a 12AU7 data sheet. It might be overheating the heater! Ideally the heater wants 12.6 volts, though 12 volts would be fine.
Good luck!
Rick
Quote from: c.wright on September 09, 2008, 05:37:10 PM
WOW. You guys are FAST.
Man, i was all proud thinking i'd troubleshot that C3 and now you blow it for me Renegadrian!! :icon_redface:
I'da thought a blocking cap would need to only let stuff go one-way?
Thanks again for the quick replies, and thanks in advance for the help!
Look where the question comes from...
It's a P in the schem but a NP in the wiring layout---
(http://www.beavisaudio.com/Projects/ValveCaster/MatsuminValveCaster.gif)
(http://www.beavisaudio.com/Projects/ValveCaster/MatsuminValveCasterWiring.gif)
And read that I've been thru the same doubt...
http://www.diystompboxes.com/smfforum/index.php?topic=63479.180
So no, that's not the issue...I've used both and don't find such a difference...
Hey man, post some sound clips when you get it all worked out. I love listening to these thing.
I can't wait to get mine up and running. Two valvecaster and a booster, but I can't quite deside on the booster. I was going to do the stratoblaster, but someone said the SHO was good infront of it. I read they were noisy though. Any other easy, simple, CLEAN booster that have been tested good with this thing?
Quote from: mth5044 on September 09, 2008, 06:47:51 PM
Hey man, post some sound clips when you get it all worked out. I love listening to these thing.
I can't wait to get mine up and running. Two valvecaster and a booster, but I can't quite deside on the booster. I was going to do the stratoblaster, but someone said the SHO was good infront of it. I read they were noisy though. Any other easy, simple, CLEAN booster that have been tested good with this thing?
PentaBoost (http://www.diystompboxes.com/smfforum/index.php?topic=70524.0)
Where do you generally have your Valvecaster "Volume" control set?
If you're anything like me, then you like gain, dirt and crunch.
That means setting the Gain pot high and the Volume pot low - right?
So, if the volume pot is set to 25% that's 75K of serial resistance cutting away at your treble.
Jeez - no wonder this circuit has the reputation of sounding a little 'dark'!
When I set up the plate resistors on my Vibracaster (http://www.diystompboxes.com/smfforum/index.php?topic=70160.0) I set it up for unity gain between the bypassed and effected signals - it doesn't suffer from 'darkness' like the Valvecaster does - no volume control > no serial resistance dragging away the highs.
I'm gonna bridge my 100K Volume pot with a 10K resistor, it will mean I can't use the Valvecaster as a clean boost - but hey, I'll just build me a PentaBoost (http://www.diystompboxes.com/smfforum/index.php?topic=70524.0) instead.
Man, did you just write an add for your pentaboost? I imagined it being like a child in a cereal commercial. :icon_lol:
I will have to check into your pentaboost. Thanks.
edit: oh man, just read about the pentaboost. I think it will do lovely in the same box with two valvecasters. Have you tried it as a boost before the 12au7 type valvecasters?
Plus now I can tell people its an 'all tube' unit. :icon_mrgreen:
how do you mount them buggers anyway? I was going to put the 12AU7's out the top, so I would like to have the little guy sticking out there to.
Quote from: mth5044 on September 09, 2008, 07:42:03 PM
Man, did you just write an add for your pentaboost? I imagined it being like a child in a cereal commercial. :icon_lol:
I will have to check into your pentaboost. Thanks.
Q:"How do you keep your teeth so shiny and white?"
A: "I only use 'PentaBoost' (http://www.diystompboxes.com/smfforum/index.php?topic=70524.0) when I brush!"or
"Take two bottles into the shower? Shampoo and conditioner? Not me - I just take 'PentaBoost' (http://www.diystompboxes.com/smfforum/index.php?topic=70524.0)....."or
"Tired of dull, lifeless guitar riffs.......?"You get the picture! Always room for humour and shameless self-promotion around here...........
Quote from: Renegadrian on September 09, 2008, 06:23:06 PM
Look where the question comes from...
It's a P in the schem but a NP in the wiring layout---
And read that I've been thru the same doubt...
http://www.diystompboxes.com/smfforum/index.php?topic=63479.180
So no, that's not the issue...I've used both and don't find such a difference...
Hah - Adriano, I wish I was that astute and could blame the discrepancy for my mix-up, but really i just wrote out a quick manifest and started slapping it together based on the layout... I didn't reference the actual schematic until I started having problems! ::) Hey, like I said, I'm a model-builder...
---
SO, I had to break for dinner and all that (wives really like it when you put down the iron and the guitar) - but I did go back over my stuff, and checked R2, and my solder joints.
The resistor metered ok, the connections are
all iffy though. Since it was a first-time build for me, i used an old socket I got from Mendelson's here in Dayton, and the thing was crusty and weird and sacrifice-able ... in retrospect, this sort of logic is probably 90% of my problems...
Also, I crammed all my parts onto the backside of that socket as close as I could get them for the sake of being compact. That might not be good either.
So, geez, you know, I could keep beating this thing to death, but it's like, EIGHT freakin PARTS?!
So I'm gonna start a new one from scratch tonight - now that i've got a 'proof of concept' build done, I'll use a NEW socket, and everything else NEW too!!!
Thank you Rick and Adriano, I really appreciate the help, and I'll try to get some kind of sound clips posted after I get the new one done!
many thanks -
Right Chris, post your results when done, ok?! :icon_wink:
I don't know if you guys remember but I built mine then the gain pot stopped working. Turns out the actual pot went bad...never had that happen. O well on a simple circuit like this that I understand it wasn't too hard to track it down.
Stock circuit minus a 33nF input cap... I don't find this circuit dark at all. Though I always have liked and have a slightly bright stock tone. Nice boost/OD.
(http://img152.imageshack.us/img152/529/dscf0129bi9.jpg)
(http://img152.imageshack.us/img152/4789/dscf0126zl7.jpg)
A great little circuit, great fun to play with.
Looks great!
Great font choice man, looks professional 8)
Where can I get some of those knobs from? I've got a pedal underway that they'd be perfect for... thanks!
Andrew, I know Banzai got them ---------->(http://www.banzaieffects.com/files/images_thumbnail/t_18777.gif) (http://www.banzaieffects.com/Neutrik-RE-AN-knob-pr-18777.html)
They are german based, I don't know if your trusty retailer got them...Else go buy them thru Banzai...
Looks great! Is that an etched design?
That looks really good, congratulations.
When you say minus the 33nf cap, what one are you talking about? The input is a 47, did you cut it down to 33 or just leave it out all together?
Quote from: andrew_k on September 11, 2008, 01:54:01 AM
Great font choice man, looks professional 8)
Where can I get some of those knobs from? I've got a pedal underway that they'd be perfect for... thanks!
I got mine from Effects Connection...50cents!! Mad cheap...only issue is they are push on. I had to drill mine out a bit and they were still quite snug on my solid shaft.
I just used decals on my pedal.
I made the input 33nF
Sorry but I can't resist this:
Quote from: kurtlives on September 11, 2008, 12:22:16 PM
Mad cheap...only issue is they are push on. I had to drill mine out a bit and they were still quite snug on my solid shaft.
...yeah, i've had some girlfriends like that ! uh, it's been quite a few years though, sadly...
But I digress -
Hello again - I'm back after throwing another valvecaster together -
This time, I used a NEW socket, NO SALVAGED parts, and I put everything but the tube/socket on perfboard, so there was no risk of weird crosstalk/shorting/interference etc.
I am also running power through a perfboarded 7812 regulator circuit.
Overall, the sound quality is
much better - where it was passable cool overdrive before, it is getting really sick good now. The noise floor seems to be considerably lower as well.
BUT - I am still getting that lousy HUM, and am still seeing 4vdc on the signal output!!!
Also, something else weird... i'll get to that in a second.
Here are numbers: (this time I'll include pin9 - i dunno why i neglected that before, i guess because it's NC)
1. 3.87 (9.5)
2. -0.266
3. 0 (.9)
4. 0
5. 11.03
6. 4.9
7. -0.219
8. 0
9. 5.68
(parenthesis explained below)
Also NOTE, I left out the TONE pot and cap (c4), left off VOL pot, was trying to simplify as much as possible.
I had left out the GAIN pot as well, but then i saw those weird numbers in parenthesis up there, and thought the omission might have something to do with it.
So I dropped in a 100k, and now I can sweep it from the low setttings on pin 1 & 3 above to the high settings in parenthesis.
The control audibly works as expected.
So I dunno what that is all about. Those high numbers are way off the mark, right? Should that gain pot be doing that?
If I run the AMP gain on 0 it all sounds typical of a stompbox app, but if I turn the AMP gain up AT ALL, the hum seems to get exponentially louder...
so, what the ?!, am I missing something here, or making some noob/fundemental mistake, or am i just tweaked?
I think I am correct in blaming the hum on the 4v on the signal output, right?! ???
ONE LAST BIG THING:
...remember i told you that i wired the power on my first build backwards (cuz i'm a dingus) -
Could I/Did I damage each of the 5 tubes I plugged in trying to get that running? :icon_sad:
Is it possible now that my tubes are all wonky, and that's where all the hum is coming from? ... as for those knobs, and those build pics.... sheesh, i wish i could build stuff that clean.
I'm usually happy if sound comes out at all. As for the knobs, I say again, Mendelson's in Dayton, Ohio, i pickup up a good sized handful of those same knobs, i think at 10cents each - problem is, that place is a mammoth warehouse, and there is very little organization, so i might never find them again!
Sorry but I can't resist this:
Quote from: kurtlives on September 11, 2008, 12:22:16 PM
Mad cheap...only issue is they are push on. I had to drill mine out a bit and they were still quite snug on my solid shaft.
...yeah, i've had some girlfriends like that ! uh, it's been quite a few years though, sadly...
WOAH, THAT MADE ME LAUGH!!! :icon_lol:
But I digress -
Hello again - I'm back after throwing another valvecaster together -
This time, I used a NEW socket, NO SALVAGED parts, and I put everything but the tube/socket on perfboard, so there was no risk of weird crosstalk/shorting/interference etc.
I am also running power through a perfboarded 7812 regulator circuit.
Overall, the sound quality is
much better - where it was passable cool overdrive before, it is getting really sick good now. The noise floor seems to be considerably lower as well.
BUT - I am still getting that lousy HUM, and am still seeing 4vdc on the signal output!!!
Also, something else weird... i'll get to that in a second.
SOUNDS GOOD!!!
IF YOU RUN PIN 3 TO GROUND YOU GET MAX GAIN OMITTING THE POT...OR DID I GO WRONG?!
ONE LAST BIG THING:
...remember i told you that i wired the power on my first build backwards (cuz i'm a dingus) -
Could I/Did I damage each of the 5 tubes I plugged in trying to get that running? :icon_sad:
Is it possible now that my tubes are all wonky, and that's where all the hum is coming from? PIN 4 AND 5 ARE THE HEATERS, BUT THEY CAN BE USED BOTH WAYS, SO NO MATTER WHICH DIRECTION YOU USED...
Quote from: c.wright on September 11, 2008, 01:49:14 PM
But I digress -
Hello again - I'm back after throwing another valvecaster together -
Pin 6 seems a little low.
The circuit wont work without the gain pot. Directly earthing pin 3 would give maximum gain without a pot though.
The hum could be a badly filtered/regulated power supply - try the circuit with a 9 volt battery and see if the hum goes away. If it does, it's the powers upply causing the hum.
Yep, I had originally run Pin 3 to ground, for simplest part setup - i knew that would give me either a min or max gain, which was fine for testing purposes.
:icon_idea: wow, actually try it with a battery! I'm a total idiot. Why didn't I think of that?!
yeah, as i said, my wallwarts are TOP quality, ;D from whatever random useless electronics sources...
(20 minutes later)
uh, well, scouring the house has turned up 3 batteries- 8.5v, 2.5v, and 7.8v ... needless to say, none of them are having any luck lighting that piece of shi... uh, shiny glass tube...
So, i guess i gotta run out for some good ol' cheap Odd Lots batteries! Nothing but the best for me baby!
Another question though: i AM using that 7812 circuit, for regulation... Should that be doing something, or is it just doing 'regulation' but not actually helping screen any crappy noise from my lousy PS?
(nice run-on question there)
And a quick word: I already mentioned how important this forum is to me, but I gotta also say, that even though i'm having trouble with this build, it is my favorite so far.
I've built a couple TS clones, Phase 45, Tremulous Lune, Orange Squeezer, Pulsar, a bunch of little booster/distorts (opamp and transistor), and a whole bunch of stuff that hasn't worked at all.
My previous fave was the Tillman, for low parts count, ease of build, and satisfying results. Just enough to hit my Marshall a leeetle beet harder on the front end, you know?
I really really wanna get the Tillman and this Valvecaster together, I think it could be LOVE, L U V.
Might I recommend the Visual Sound 1 Spot adapter for this project? They have a 12v version. Can handle 1500mA :icon_eek: and is ~$20. I have three of the 9v one and they are totally silent and have not died yet. I plan on getting one when I get around to this project. Just my 0.02.
Chris, the 7812 is mainly for regulation, you should put some filtering too - as suggested in the previous pages, a 100µF el.cap between + and - on the DC jack filters a good amount of s**t.
Quote
I really really wanna get the Tillman and this Valvecaster together, I think it could be LOVE, L U V.
I tried the two togheter - I think you are going to like them coupled...
edit
Ok, still haven't run out for 9v batts yet, but going to after supper -
Tried the 100uf electro on the PS both before, and after regulator, didn't really do anything. Maybe took away a teensy hiss.
Tried higher values out of frustration :icon_confused: - some of those seemed to really muddy up the hum, but still didn't get rid of it.
:icon_idea: I had a thought that maybe that 100k/220k pair were too wimpy (eh, remember, i'm very short on theory), so I pulled them and found a couple cool carbon-comp resistors that are bigger. Might be the same wattage though, i dunno. They seemed to improve the hum to an extent, and seemed to reduce the voltage on the signal output by about a volt.
But what is weird though too, the gain control, when rolled back the gain goes down and the hum goes UP.... not an aural illusion either, it's REALLY noticable, esp with the guitar quiet.
The Visual Sound 1 spot - yes, that seems a good deal at $20, i may just invest in one of those.
I DO have a Boss PSA, but it's enclosed in my pain-in-the-butt pedal board ... I might just have to break it out tonight... once i do though, i'll never get the backside back on that thing. Oh well, it really needs a good tweaking anyway. My mechanical engineering is about as good as my electrical.
But, can anyone else confirm for me whether they are getting voltage on the signal output (FOUR VOLTS?!), am I an idiot here, that just can't be right, can it? Am I gonna cook my amp?
I promise to reward everyone for their time with some cheescake pix and more dumb questions! ;D
You could dub it LUXURY CASTER when you're done, right?! :icon_wink:
Man, I like your band...
Ok, i got batteries, but the device doesn't want to run off of them.
The filaments light up - and with one of the batteries i could hear the faintest of sounds, but basically nothing.
So, does that point to a serious error somewhere or something? Did I get an old revision of the schematic or something? I've looked at that PDF of all the compiled stuff from everyone's posts, and I didn't see anything in there that looked out of place.
I just dunno what is going on. If I could just get rid of that hum it would be insane.
Eh - Glad you like the band Adriano - sadly, June was the last month it existed for all intensive purposes.... See, the singer.... eh, it's a long story, but not such a great guy, and after 3 years for me, 2 for the drummer, and FIVE for the bass player, well, everyone's had enough.
The band basically imploded a couple months ago, though I think the singer is going to try to get some schlubs to fill in for some October dates. I'd be happy to give you copies of the albums, or access to download them, if you're interested. I guess just shoot me your email in a private message?
did get a lot of GREAT rock photos from playing in that band - i will miss that.
I got a new thing starting up though - waaaay different, but i'm gonna make a buck at it this time around.
eehhhhhhh........ but VOLTAGE on my signal out? - do i need to explore 'coupling/decoupling' or something?
I guess my next step is to try to sub out each of my components until maybe i hit something that was faulty or ?
oh, and get out the Boss PS and see if that works.
any other suggestions are appreciated.
soorry on the long delay - weird week in Dayton, we were a disaster area! :o ...remnants of Ike...
OK - the BOSS PSA power supply has eliminated the BAD HUM that I was experiencing, and I think put it into the realm of 'totally usable' now - ;D
I haven't swapped that input cap, but I think it sounds great on humbuckers or single coils so far! Can't believe how much crunch you can get out of it, I might look into one of those 'clean boost' mods listed in the PDF, or maybe on the next build.
Voltage on the signal output is down to 2.5v now, which still seems absurd to me, but i don't know where to start troubleshooting, or if that is even trouble. I read a post somewhere that said something like "try metering your pedals output for DC, you'll be surprised!" but it didn't really offer much by way of answers - just implied bad components/construction and/or design...
So, I guess I'll have to look into buying a few DECENT power supplies, and get rid of some of the garbage i've been using.
Success on this has inspired me to revisit some old projects I never got running - a Boss FA1, Jade Fuzz, and and Uglyface... we'll see if I get anywhere on those. If I do, I've got abot 20 others to revist after that!
thanks for the help!
Quote from: c.wright on September 19, 2008, 01:38:53 PM
OK - the BOSS PSA power supply has eliminated the BAD HUM that I was experiencing, and I think put it into the realm of 'totally usable' now - Grin
GREAT to hear that you got it working! ;D
Got pics or sound clips of the build?
I also use the BOSS PSA120T, 200mA, it's a great little power supply provides good clean power. Much better than it's little brother ACA120, 200mA which puts out a lot of hummmm. (They are little work horses, had them for over 15 years or so and they all work fine)
Well, it's all still all alligatored all to heck, perfboarded the parts, and no outboard stuff yet, it's all just on my little "test-bed" i "built" ::) dunno how i'm gonna mount the tube socket somewhere, it's pc mount i think...
... but i'll get a couple pics of that mess cuz you guys will like to see it, and then i'll box it up and bring it up to the computer for some sound bites. Might be a minute (=days), but i'll get that much done!
The bonus is: I actually built TWO, because i thought the first was F@#$@#$'d, and since i've narrowed it done to my awful p-supplies, that means i'll have both in the bag at once!!
Thank you everyone for your help and encouragement, even though I'm just a 'paint-by-numbers' builder, (or 'model builder' as I like to call it - y'know, like 1/72 scale Spitfires? - I build 2/1 scale distortions ;D) ... even though I'm only at that level, I still have learned TONS OF STUFF from this FORUM and from the builds.
Every time I finish something and it works, it's like winning a trophy or something!!! And just think of the money I'm saving, I probably ONLY have like $1500 invested in the 4 or 5 reliable pedals I've built ! :icon_eek:
Congrats on the build. You should put cascade them and tell us what you think.
Quote from: c.wright on September 19, 2008, 03:09:32 PM
Thank you everyone for your help and encouragement, even though I'm just a 'paint-by-numbers' builder, (or 'model builder' as I like to call it - y'know, like 1/72 scale Spitfires? - I build 2/1 scale distortions ;D) ... even though I'm only at that level, I still have learned TONS OF STUFF from this FORUM and from the builds.
Every time I finish something and it works, it's like winning a trophy or something!!! And just think of the money I'm saving, I probably ONLY have like $1500 invested in the 4 or 5 reliable pedals I've built ! :icon_eek:
Eheh, hey model builder!!! :icon_lol:
Glad you have a good valvy...Now it just needs a decent box...Hope you enjoied building it, after all that's what the DIY is about...Have fun, build nice pedals and learn something new...
eh, cascading, and soundclips, and running with a tillman pre, etc., will be forthcoming...
for now, feast your eyes... on the mess... that IS... my workbench....
:icon_twisted: muhahaHAHAHA :'( (sob.)
(http://www.wrightfield.com/stompbox/P9199776.JPG)
naw, it does me ok. I could probly keep it a little bit cleaner... :icon_neutral:
can you spot the quote testbed unquote?
here's the current state of the 'real good' one... i forgot to get a closeup of the other.
also, i already pulled my i/o wires and stuff because i started messing with that fuzz jade again -
that other little piece of perf i think is an LPB1 that I need to box up.
(http://www.wrightfield.com/stompbox/P9199777.JPG)
and speaking of boxes, I have NO problems there... except for WHICH to CHOOSE?
(http://www.wrightfield.com/stompbox/P9199778.JPG)
Lastly, a couple 'cheesecake' shots for ya - a shelf of stuff i've built and boxed, that actually works - and then a big pic of some of the other pedals i own...
(http://www.wrightfield.com/stompbox/P9199781.JPG)
(http://www.wrightfield.com/stompbox/P9199782.JPG)
(http://www.wrightfield.com/stompbox/P9199783.JPG)
sorry for all the blur, and hope reveling in the pron isn't too off topic here... i just can't help myself.
sound clips RSN, i promise!
Quote from: c.wright on September 19, 2008, 08:26:45 PM
for now, feast your eyes... on the mess... that IS... my workbench....
:icon_twisted: muhahaHAHAHA :'( (sob.)
(http://www.wrightfield.com/stompbox/P9199776.JPG)
It reminds me of this...
(http://bp1.blogger.com/_k9i5BR1aNww/R7ZdDnFDRQI/AAAAAAAAADc/xqnE6cuaVDc/s400/Helloween+-+Dr.+Stein+-+front.jpg)
Hah - yep Adriano, that's a good comparison - my creations are generally monstrosities that don't last too long in the light of day!
Ah yes, Helloween... did you somehow sense my metal roots?
btw, i added some little tags to those pics to help make sense of things.
I'm off to try to box up a tube or two!
This afternoon I managed to get SOUND out of my Jade Fuzz, so I'm on a roll.
Wish me luck...
Question:
Those who are using a 78xx regulator, I'd be interested in your readings. The notes for the regulators say Vin should be 3v over your Vout. If you want 9v out, put 12v in. Is that holding true?
Build 'feelings':
Over the last week I've built and playing with two AU7 vavlecasters. The second I built is a clean boost (R2 100K, R3 47K, C1 .022uF, no tone stack) and is in the chain before the second, which is as per Dano's on-the-socket layout. Both are running at 9v at the moment.
I've left the boost on all the time, and the second is used as a switchable overdrive. I tried a Rangemaster in front of the clean boost, where it just distorted everything. However, put between the two, it pushes the 'overdrive' valvecaster pleasantly.
If you are breadboarding a twincaster, try a booster between the two "circuit-ettes". It may suit your needs- then it may not! ;)
I might try a vibracaster next... See you over in that thread.
!!!!!!!!!!!!! You have one of the morley oilcan do-dads! Oh man. Plus plenty of other stuff. Luckly its all jambled around in a workspace, so if someone breaks into your house, they wont realize theres thousands of dollars crammed in there. Geez man you should move that stuff to a volt or something.
Yeehaa! A friend of mine gave me a whole bunch of tubes, mostly 12AU7, he found an incredible stock (about 200 tubes) in his garage, some of them might be dead but I found some good references (Telefunken)..
There are also a lot of PCF, ECF, PCL tubes, I don't know if these are usable for low (or high) voltage amplifier circuits, but that is so good, I'm ready to build a bunch of tube pedals.. :icon_biggrin: :icon_cool:
Quote from: Franky on September 21, 2008, 05:48:26 PM
Yeehaa! A friend of mine gave me a whole bunch of tubes, mostly 12AU7, he found an incredible stock (about 200 tubes) in his garage, some of them might be dead but I found some good references (Telefunken)..
There are also a lot of PCF, ECF, PCL tubes, I don't know if these are usable for low (or high) voltage amplifier circuits, but that is so good, I'm ready to build a bunch of tube pedals.. :icon_biggrin: :icon_cool:
Awesome! Looking forward to seeing some builds soon! :D
Hi all,
I just finished building a Twincaster with switchable second tube stage.
My problem is that the pedal is VERY quiet. Even with only one tube stage the output signal is MUCH lower than the input signal. I've checked the circuit a few times. When I turn up the Gain the signal gets distorted , but the output signal is always very low.
I tried running it at 9 and 12 Volts. No change. Any ideas?
Thanks
Voltages with pedal running at 12V
PIN1 9,14
PIN2 -0,44
PIN3 0,006V
PIN4 0,00V
pIN5 12,33V
PIN6 10,07V
PIN7 -0,38V
PIN8 0V
PIN9 6,1V
Or should I better post voltages at 9V ?
Here's mine (again):
Pin 1: 3.02v
Pin 2: -0.518v
Pin 3: 0.00v
Pin 4: 0.00v
Pin 5: 11.97v
Pin 6: 8.21v
Pin 7: -1.285v
Pin 8: 0.00v
Pin 9: 5.91v
Your pin 1 voltage is way too high - are you sure you have the corect value resistor?
Pin 6 is also a little off. Thats both your plate voltages off.
Hm, checked R1. Its 999 Ohm.
Quote from: Smiler on October 06, 2008, 03:07:30 PM
Hm, checked R1. Its 999 Ohm.
Yeah, that's a 1K resistor you have there, not a 1M. Like having a volume control at the front end turned almost all the way down.
Sorry its 999 K ... I used the right one but my post was wrong
Check the value of the resistors at pins 1 and 6 too.
R2 220K
R3 100K
Seems to be ok.
How muck boost of your input signal do you have? Maybe I expect too much?
When Gain is a litle above 3/4 then the output level is equal to the input level (but overdriven as it should be)
It should have plenty of gain and boost. Set the gain to maximum and the volume to unity with the bypassed signal - measure the ohmage of readings between the volume control lugs. I'll compare yours to mine. Probably best to debug the two valvecaster circuits seperately
Ok, I think I found out the problem. I debugged both stages separately. Both work fine. The tone stack I added was the problem. Without it all voltages seem to be normal and the pedal has enough boost ;-)
Maybe I find another tonestack which works.
Smiler, glad you finally got that one working...So is my layout verified??
Impressions on that one or sound samples??
Quote from: Smiler on October 12, 2008, 05:06:44 PM
Ok, I think I found out the problem. I debugged both stages separately. Both work fine. The tone stack I added was the problem. Without it all voltages seem to be normal and the pedal has enough boost ;-)
Maybe I find another tonestack which works.
Tonestacks seriously suck gain. If you want one you'll need a recovery or boost stage.
Quote from: Smiler on October 12, 2008, 05:06:44 PM
Ok, I think I found out the problem. I debugged both stages separately. Both work fine. The tone stack I added was the problem. Without it all voltages seem to be normal and the pedal has enough boost ;-)
Maybe I find another tonestack which works.
You can increase the volume of a Valvecaster by changing R3 to 220K or higher, if you do this for both stages it might be enough to compensate for the tonestack volume loss.
EDIT: You should get even more volume by increasing R2 as well, 470K maybe.
@Renegadrian:
Not 100% Yet ;-) I completely rebuilded the whole pedal to find this error. Tested the first and then the second stage. After adding the tone stack the pedal becomes very quiet and all voltages become strange. Don't know why. I'm testing at the moment, but your Twincaster board-layout (Twincaster rev 0_11.jpg) looks good. My first build was an enhanched version of your layout (with switchable second tube stage and tone stack). My current build has no board. The tons of wires make it more difficult to debug ;) By the way: Why do you use electrolytics for C3 ?
@kurtlives & frequency central:
I've heard that it sucks gain. Anyway I'm confused about the voltages when using the tone stack. PIN2 has about 4V without and about 9V with tone stack. Will try using 220K for R3 tomorrow.
Quote from: Smiler on October 12, 2008, 05:57:14 PM
Anyway I'm confused about the voltages when using the tone stack. PIN2 has about 4V without and about 9V with tone stack. Will try using 220K for R3 tomorrow.
Are you sure you have a DC blocking cap between the tonestack and pin 2 - that would be C1 in the schematic.
Quote from: Smiler on October 12, 2008, 05:57:14 PM
@Renegadrian:
Why do you use electrolytics for C3 ?
http://www.diystompboxes.com/smfforum/index.php?topic=63479.msg568630#msg568630
See here at page 39 :icon_wink:
Quote from: frequencycentral on October 12, 2008, 06:02:08 PM
Are you sure you have a DC blocking cap between the tonestack and pin 2 - that would be C1 in the schematic.
Yes, 47nF...
Quote from: Smiler on October 12, 2008, 06:12:02 PM
Quote from: frequencycentral on October 12, 2008, 06:02:08 PM
Are you sure you have a DC blocking cap between the tonestack and pin 2 - that would be C1 in the schematic.
Yes, 47nF...
Maybe you should have one either side of the tonestack.
Hey Adriano - how's it hanging? Another Valvy question and we all come out of the woodwork.......
.......did you like the Red Star Drive (http://www.diystompboxes.com/smfforum/index.php?topic=71350.0)?
yeah man, you're right, I've been a bit busy those last days...
I love all of your tube layouts, the latest too, while you know I am a high gain fan...
Still I like some low gainers, like the pentaboost...
Adding a 47nF DC blocking cap didn't work. Still 9V on PIN 1 and low output. I didn't try changing R3 and R2 yet but would it really increase volume and NOT gain?
Someone here said he build up a valvecaster with tone stack. Does anyone know a (passive) tonestack that doesn't suck volume? If not I will build up a regular Twincaster with tone control only. Have six holes in the enclosure, but there will be a way to close them with a label.
Quote from: Smiler on October 13, 2008, 01:48:17 PM
Adding a 47nF DC blocking cap didn't work. Still 9V on PIN 1 and low output. I didn't try changing R3 and R2 yet but would it really increase volume and NOT gain?
Someone here said he build up a valvecaster with tone stack. Does anyone know a (passive) tonestack that doesn't suck volume? If not I will build up a regular Twincaster with tone control only. Have six holes in the enclosure, but there will be a way to close them with a label.
In a standard Valvecaster, increasing R2 will increase the gain, increasing R3 will increase the volume.
If you can't find a suitable tonestack (I don't know of one that doesn't suck gain), you could add the Vibracaster (http://www.diystompboxes.com/smfforum/index.php?topic=70160.0) tremolo mod to your twincaster, that would add two more knobs, rate and depth.
Here is a tone control that has quite low insertion loss. Change capacitor values if nessesary.
(http://www.tg-music.com/Gibson%20GA-30RVT%20Tone.gif)
Hm, looks nice but I don't have any of this 6111 here :(
BUT I removed the tone stack, replaced it with standard tone+volume pots and FINALLY got a nice idea :)
I will add a second tone and volume control for the second tube! Have 3 free pins left on the 3PDT that enables the second stage. So either the first or the second tone+vol controls are enabled depending on the second tube stage being on or off ;D
Only have to buy pots & stuff.
Quote from: SirElwood on October 13, 2008, 04:26:04 PM
Here is a tone control that has quite low insertion loss. Change capacitor values if nessesary.
(http://www.tg-music.com/Gibson%20GA-30RVT%20Tone.gif)
no resistor from grid to ground?
Quote from: Smiler on October 13, 2008, 04:54:21 PM
Hm, looks nice but I don't have any of this 6111 here :(
Should work identically with 12AU7. :icon_biggrin:
Quote from: snap on October 13, 2008, 05:35:23 PM
no resistor from grid to ground?
That is an error on my drawing. :icon_redface: But that tone part is correct.
And yes, it will work with 12AU7 as well.
Hi :)
Finally got my Twincaster working! I added second tone and volume controls. Switch 1 is a 3PDT, so I labeled it SW1a and SW1b. There is also an LED connected to it (not shown here). So I have independent tone and volume depending on having tube B active or not.
If someone will also build it like this, here you are:
(http://i386.photobucket.com/albums/oo302/Smiler/TSschem-1_switchable.jpg)
Based on mth5044's Schematic.
I will post pictures of the whole pedal when I've finished the enclosure-design :)
EDIT: corrected SW1a position
Wow, it seems like I've missed the last 25 pages or so... I guess I've been busy building Valvecasters or something.
Here's a little video of my latest which is going out to a hopefully happy customer tomorrow. It's the 11th Valvecaster I've made.
People love these things. This is a stock version. Only thing I've done is to put a 3pdt switch in there. It's on (but bypassed) once you plug in the power and a guitar cable, so you don't need to wait for the tube to heat up once you push that button.
http://www.youtube.com/watch?v=3cMqYlhSQ8c
Okay, okay I'm sorry about the crappy playing and that blue LED. I didn't have any other colours. Honestly. :icon_rolleyes:
Quote from: Krinor on October 22, 2008, 05:52:40 PM
Okay, okay I'm sorry about the crappy playing and that blue LED. I didn't have any other colours. Honestly. :icon_rolleyes:
I use two blue ones :D
Blue LEDs and polished metal enclosures look sooooo gooooood. Better then anyother color IMO.
Looks good.
Just a little update for the knowledge or the DIY community...
I just finished my 7th Valvy, using a 9AU7 (and a 7809).
Works good and there are no big differences. Easy to find that tube on evilBay for little $$$
Just another experience: Especially if someone will build a Valvecaster with two tubes, USE A 7812 !
I had problems with lots of hum. With two tubes -> more hum. Just builded up a little circuit with 7812 regulator and two (not too small) elelectrolytics. Works great!! Just shhhhh and no HUMMMMMMMM ;-)
Even my so called 12V "regulated power supply" was a little crappy. Now I've found a cheap 18V 650mA power supply which works.
Here's my 8th Valvy - I found this little box, actually designed to hold coins, and I went - Would it be crazy to build a Valvy inside one of those? Hell yeah - ok, I have to do it!!!
So here it is!!! I dedicated it to my gone too soon daddy, who left us ten years ago. It was a rainy november day, just like today...
I know he'd appreciate...
(http://img136.imageshack.us/img136/6564/valvy008nw4.th.jpg) (http://img136.imageshack.us/my.php?image=valvy008nw4.jpg)(http://img136.imageshack.us/images/thpix.gif) (http://g.imageshack.us/thpix.php)
Quote from: Renegadrian on November 07, 2008, 06:00:58 PM
Here's my 8th Valvy - I found this little box, actually designed to hold coins, and I went - Would it be crazy to build a Valvy inside one of those? Hell yeah - ok, I have to do it!!!
So here it is!!! I dedicated it to my gone too soon daddy, who left us ten years ago. It was a rainy november day, just like today...
I know he'd appreciate...
(http://img136.imageshack.us/img136/6564/valvy008nw4.th.jpg) (http://img136.imageshack.us/my.php?image=valvy008nw4.jpg)(http://img136.imageshack.us/images/thpix.gif) (http://g.imageshack.us/thpix.php)
Man that makes me sad - but 8 >>> you are the Valvecaster Master!
anyone has made a mod increasing the beavis audio valvecaster gain?
(my valvecaster runs with 12 volt power supply!)
Quote from: robizz on November 08, 2008, 03:54:17 AM
anyone has made a mod increasing the beavis audio valvecaster gain?
(my valvecaster runs with 12 volt power supply!)
Have a look at this: http://www.diystompboxes.com/smfforum/index.php?topic=71864.0
Now Tube Town have a Valvecaster varient: http://www.tube-town.net/diy/lov/lov03-bananabooster.html
hhmmm I just built one. but there is a little radio frequencies. other than that, it sounds really good.
I checked GEO debugging page and followed the instruction and mine is true bypass with 3pdt switch,
sorry dumb question but for the shielding, mine enclosure have some vents like little holes. does this effect?
sorry i dunno what else to do..
Well, I'm finally getting around to building the damn thing (two valvecasters and a 5672 boost in one box), and the design I'm going to implement has room for a bunch of switches, probably 6 TOPS! Reading the PDF, there are a lot of mods, so I thought I'd ask.
What is your favorite mod(s)?
Quote from: mitzrecords on November 11, 2008, 08:01:03 PM
hhmmm I just built one. but there is a little radio frequencies. other than that, it sounds really good.
I checked GEO debugging page and followed the instruction and mine is true bypass with 3pdt switch,
sorry dumb question but for the shielding, mine enclosure have some vents like little holes. does this effect?
sorry i dunno what else to do..
I don't think that the holes have a big influence... Try to connect all ground wires to a single point (input or output jack) if you don't have already. Another thing you can try is to connect the case to ground (some signal and DC jacks are isolated and maybe there is no connection from ground to the case).
I realised I still hadn't used the NOS American (CBS) 12U7 that Brett kindly hooked me up with about 18 months ago.
So last night I threw together a Valvecaster - and WOW. I can see what everyone's raving about. A definate "authority" to the sound, with gorgeous breakup when I crank the gain. My stock Tele loves it, but a hot Dimarzio humbucker really brings out the best. A Shin Ei FY-2 in front of it sounds b*****d heavy but removes the dynamics completely.
Now to breadboard LPB-1, Sparkle Boost (any other boost suggestions?) and a few others and find the best booster to put in the box.
I'm using a decent 12V wallwart and have no noise issues. I used a 100Kb pot for the gain control but otherwise built stock. The caps in the diagram are perfect for me (I used green beasties), not too bright or dark.
Love it!
Quote from: Cursor on November 15, 2008, 09:07:17 AM
Now to breadboard LPB-1, Sparkle Boost (any other boost suggestions?) and a few others and find the best booster to put in the box.
PentaBoost (http://www.diystompboxes.com/smfforum/index.php?topic=70524.0) - keep it all tube!
Quote from: frequencycentral on November 15, 2008, 09:10:46 AM
PentaBoost (http://www.diystompboxes.com/smfforum/index.php?topic=70524.0) - keep it all tube!
- Hmm, there's a thought. If only I had subminis. I could trawl through the tubes box for other space charge pentodes, but I believe I'm completely out of sockets now.
I'm tempted to nick the ECH83 triode-heptode preamp and PSU out of my hybrid amp (http://www.coldcity.com/index.php/hybrid-guitar-amp/). I wonder how the 12U7 Valvecaster would handle a B+ of 20V. Datasheet suggests it'd be OK, but I'm not sure I even want the headroom; I really like the sound as is.
Also, solid-state would definately fit in the box ;D
i was wondering if it could be easily changed to run a 12at7? i don't have time to read through all the pages, so i just want to see if it is posible as this is the only of the 12a*7 series tubes i have now.
It will probably run just like it is with a 12at7. The only thing is you migght get massive ugly distortion, but maybe not. You will definitely get more gain, as 1t7 is higher gain than au7, but IIRC it has higher Ip, I don't know if that will affect this circuit or not.
Might as well try it for now and then just put in the 12au7 later.
Zach
ok, i will just go with that ;D
I did try a 12at7 in it in the past - no big differences...but I'd stay with the u's...
Cant find it now... What are the "clean" mods? I remeber it involved the plate resistors.
Quote from: kurtlives on November 17, 2008, 10:11:44 PM
Cant find it now... What are the "clean" mods? I remeber it involved the plate resistors.
Halve them.
:icon_lol: Hi guys,
I have built this matsumin valve caster, it's sound good for me. But, i want to add more Gain, how to do that. And i feel some compressed sound if i turn the gain pot to max. I want to increased the gain to get a "picking: sound.
Need your help, thanks.
Quote from: squallc on November 25, 2008, 10:29:42 AM
:icon_lol: Hi guys,
I have built this matsumin valve caster, it's sound good for me. But, i want to add more Gain, how to do that. And i feel some compressed sound if i turn the gain pot to max. I want to increased the gain to get a "picking: sound.
Need your help, thanks.
Have a look at this: http://www.diystompboxes.com/smfforum/index.php?topic=71864.0
It's not quite a Valvecaster, but based on it. And it needs verifying.
Quote from: squallc on November 25, 2008, 10:29:42 AM
:icon_lol: Hi guys,
I have built this matsumin valve caster, it's sound good for me. But, i want to add more Gain, how to do that. And i feel some compressed sound if i turn the gain pot to max. I want to increased the gain to get a "picking: sound.
Need your help, thanks.
You could try a bypass cap on the gain pot. Try 0.68mF for a bit more bite and gain or 22mF for a nice linear boost.
Another experiment report for the records...
I tried to put in a 6021 (submini dual triode tube) powering the heaters thru a 7806 (it must receive 6.3 V)
The pins follow the 6111 schematic you can find in the first pages
It works but the sound it's not good at all...Guess I have to breadboard it and find the mandatory tweakings that could make this tube shine!!! Not for now, though...
http://www.etsy.com/view_listing.php?ref=cat2_galley_9&listing_id=17111340
$139...
Looks pretty lame, for $140 I would expect it as least painted. The description is pretty funny.
Wonder who's vero layout he used ::)
did he show up here yet?
http://www.happyrobotmusic.co.uk/info.html
I like the fact that that pedal wont work for half the people considering he put in a 12v reg and is saying to use a 12v supply. Anyone who tries to use a 12v regulated supply is gonna get nothing :icon_eek:
Zach
Quote from: Zben3129 on November 29, 2008, 12:20:24 PM
I like the fact that that pedal wont work for half the people considering he put in a 12v reg and is saying to use a 12v supply. Anyone who tries to use a 12v regulated supply is gonna get nothing :icon_eek:
Zach
though exactly the same when i read it :)
Quote from: kurtlives on November 28, 2008, 10:11:17 PM
Looks pretty lame, for $140 I would expect it as least painted. The description is pretty funny.
Wonder who's vero layout he used ::)
This is from his website.
Many thanks and respect to Andrew Carrell for providing such good layouts which some of these pedals are based on.
If you want to know more about making your own guitar pedals please visit www.diystompboxes.com
Andy never made a vero layout for the Valvy though.
Quote from: Renegadrian on November 28, 2008, 07:34:54 AM
Another experiment report for the records...
I tried to put in a 6021 (submini dual triode tube) powering the heaters thru a 7806 (it must receive 6.3 V)
The pins follow the 6111 schematic you can find in the first pages
It works but the sound it's not good at all...Guess I have to breadboard it and find the mandatory tweakings that could make this tube shine!!! Not for now, though...
Here you go Adriano. The first schem is straight high gain. The second is med/high gain with over the top gain switching. Also added an EQ by-pass switch to allow the full tone without any loss.
Sounds good at 18 volts but increase the voltage and it becomes more amp like, especially above 24 volts. With some minor tweaks it works at 12 volts, but at 12 volts it is hard to get the palm muting chunk you want with high gain.
(http://img.photobucket.com/albums/v316/jered1011/HighGain6021.jpg)
(http://img.photobucket.com/albums/v316/jered1011/MediumandUltraHighGain6021.jpg)
Can you explain the 470pF caps going from plate to cathode on some tubes? Shave off some highs?
Also whats the point of the 2M2 and that cap (cant read value) from the plate to grid? Seen this before in some Dumble designs, some form of NFB?
I like your use of filters throughout, original design?
Jered, you're the man! :icon_wink: Guess I'll have to send you some more Rome souvenirs...
THX again for the tubes and for your kindness. And for those schems too! I'll try the first next week!!!
scusa renegadrian io sono di carpineto romano e vengo tutti i giorni a roma perchè studio alla sapienza, ma queste mini valvole le posso trovare anche nella capitale?? :icon_lol:
Check this out,it should be correct...I'll try it for sure, Jered, I surely look for high gain and got a 6021 handy waiting to be heated...
EDIT: I inverted the order of the 2 res at the input (pulldown comes after) - I believe it's the same thing, isn't it?
(http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=37853&g2_serialNumber=1)
BUILD REPORT
Unfortunately this thing doesn't seem to work...Gotta check it better tomorrow, maybe I went wrong on the soldering or the layout has something wrong (pls check it!)
The tube lights on, and that's ok...it gets its 6v thru the 7806...But no sound at all... :icon_cry:
I run it at 12V, I know 18 or 24 would give more headroom, but only got a regular wall wart around, so I put 12V
I guess it should give some sound anyway...
Quote from: kurtlives on November 25, 2008, 04:03:26 PM
Quote from: squallc on November 25, 2008, 10:29:42 AM
:icon_lol: Hi guys,
I have built this matsumin valve caster, it's sound good for me. But, i want to add more Gain, how to do that. And i feel some compressed sound if i turn the gain pot to max. I want to increased the gain to get a "picking: sound.
Need your help, thanks.
You could try a bypass cap on the gain pot. Try 0.68mF for a bit more bite and gain or 22mF for a nice linear boost.
Thanks, bypass Cap will add some gain, but it is on the first stage, how about the second stage of 12 AU7? i'm sure it will generate more harsh/fuzz sound?not an overdrive. Actually, i need some bite sound/ more picking sound with a super sensitive.
Layout looks ok. Maybe it won't work at 12 volts. I'll put it back on the breadboard and give it a try at 12 volts. I'll report back.
OK just breadboarded it at 12 volts and it works fine. Loses a little headroom at 12 volts but still sounds real good.
Jered, I checked my vero again - The layout is correct, I just made a late night error at building, I soldered a cap in the wrong tracks...obviously the signal path was broken and then...NO SOUND!!!
Made the right connection and VOILA' IT WORKS!
I get a Valvecaster-like gain at 12V, I believe 18 or 24 surely give more headroom.
A good power filtering is MANDATORY.
THX again for your work. :icon_wink:
(http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=37853&g2_serialNumber=3)
Back on the standard Valvy - a friend reported me the following mods he made...
R2 (orig. 220k) 56k to avoid distortion at min gain.
R3 (orig. 100k) 560k he gets a nicer gain, in his words...
gotta try them...just two res. swap...
He also puts a 1µF cap at the 7812 between ground and Vout, in place of the 100µF between Vin and ground.
Some how, i cant find the power regulator anymore... Im using 2 transistors one for 12V and the other one for 9V. There are punch on caps and that all. I got a schematic somewhere, but i cant find it anymore. Some one?
Quote from: Jered on November 29, 2008, 11:05:48 PM
Quote from: Renegadrian on November 28, 2008, 07:34:54 AM
Another experiment report for the records...
I tried to put in a 6021 (submini dual triode tube) powering the heaters thru a 7806 (it must receive 6.3 V)
The pins follow the 6111 schematic you can find in the first pages
It works but the sound it's not good at all...Guess I have to breadboard it and find the mandatory tweakings that could make this tube shine!!! Not for now, though...
Here you go Adriano. The first schem is straight high gain. The second is med/high gain with over the top gain switching. Also added an EQ by-pass switch to allow the full tone without any loss.
Sounds good at 18 volts but increase the voltage and it becomes more amp like, especially above 24 volts. With some minor tweaks it works at 12 volts, but at 12 volts it is hard to get the palm muting chunk you want with high gain.
(http://img.photobucket.com/albums/v316/jered1011/HighGain6021.jpg)
(http://img.photobucket.com/albums/v316/jered1011/MediumandUltraHighGain6021.jpg)
is it possible to use the second schematic like a little preamp at low voltage (18/24 V)??
FINALLY put everything together!! ::)
After a while my Twincaster is finished. Got some pictures for you:
(http://i386.photobucket.com/albums/oo302/Smiler/IMG_3228.jpg)
(http://i386.photobucket.com/albums/oo302/Smiler/IMG_3229.jpg)
(http://i386.photobucket.com/albums/oo302/Smiler/IMG_3221.jpg)
More Pictures: http://s386.photobucket.com/albums/oo302/Smiler/
Enjoy and thanks for your help finding errors!
It looks so nice! Congrats on this one!!! (http://forum.ubuntu-it.org/Smileys/xmas-smileys-new/grin.gif) (http://forum.ubuntu-it.org/Smileys/xmas-smileys-new/good.gif)
That's really Smiler.
Although you might want to watch out when changing the knob settings.. if the tubes get hot.
Ouch. :icon_mrgreen:
Tube-Builders do it "Sticking Out"!
:icon_cool:
(http://forum.ubuntu-it.org/Smileys/xmas-smileys-new/rotfl.gif)
my green machines...
(http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=38072&g2_serialNumber=1)
Triode Triode
I made a layout last month and built it, but it didn't work at first, I debugged it yesterday, and well, it was just a track break I forgot - now it works so good and it surely has a good amount of gain!!!
I read some posts about it at page 9, but it's not clear if the design is by brett, and the schem doesn't report its creator...
So brett, if it's your work, let me know and I'll add proper credits in my layout,ok?
(http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=38098&g2_serialNumber=2)
Quote from: Renegadrian on December 24, 2008, 06:41:59 AM
Triode Triode
I made a layout last month and built it, but it didn't work at first, I debugged it yesterday, and well, it was just a track break I forgot - now it works so good and it surely has a good amount of gain!!!
I read some posts about it at page 9, but it's not clear if the design is by brett, and the schem doesn't report its creator...
So brett, if it's your work, let me know and I'll add proper credits in my layout,ok?
(http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=38098&g2_serialNumber=2)
I don't see a schematic for that on page 9 - looks like its disappeared! Can you post one? How does it compare with the stock Valvy?
I really liked your Vibracaster soundclips by the way Adriano.
(http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=38100&g2_serialNumber=1)
this is the schematic I used - just changed the uper parts, but that's just the power section - actually it hasn't got a 7812 but I think I'll put one in - for now it's just a vero with "flying wires"
It's not that far away from the Valvy...maybe a little more gain...I'd suggest you to try it, after all it's just a simple circuit...
Still working on the V2, but the trimpot you suggested me didn't work...
I am glad you liked my Vibracaster and its samples - thx for such a good circuit!
I am raising my glass of Nero d'Avola wine at that tube s..t!!! yeah!!!
Looks identical to the Valvy but with larger value caps, and gain set to maximum. Probably more bottom end, and the 500k volume pot will make the maximum volue louder (maybe?) Too similar for me to build really.
I've just cleared my breadboard of my last project (Multimode Filter), so I'm gonna have a play with "V2" again over the holiday.
Well after reading all 45 pages i have spent several hours soldering up a twincaster on vero (thanks Renegadrian!). I'll have to pick up some tube sockets on Saturday am and then fiddle with r2/r3 values but it's otherwise pretty ready to be fired up. I dug out my rca 12au7 and philips JAN 12at7 so i can see what this thing can do. I'll be going for a high gain application on bass guitar. Hope this sounds good on bass!!!
Right, post the final results then!!! :icon_wink:
I have a question about the pedal sale situation: I am planning on building one of these, and selling it on Ebay for a few extra bucks (college loans suck, don't they?! :icon_confused:). Is there any legal implications that I must know before doing this? I feel like matsumin is going to sue me or something :o...lol....I just want to make sure I don't do anything stupid. Thanks
Build it for yourself - don't sell it.
Hi there, I have built this Original Mitsumin Valvecaster, actually, i have some loud HUM sound, is it probably because of power supply? how to clean the power supply?
Need your suggest to clean this HUM.
Thanks
Quote from: squallc on January 06, 2009, 06:33:32 PM
Hi there, I have built this Original Mitsumin Valvecaster, actually, i have some loud HUM sound, is it probably because of power supply? how to clean the power supply?
Need your suggest to clean this HUM.
Thanks
You see that 'Triode Triode' schematic a few posts above your post? Build the voltage regulator part of that circuit and apply it to the plates of your Valvecaster. :icon_biggrin:
Rick, it should be quieter than the 100µF alone on the dc jack, am I right?!
Quote from: Renegadrian on January 06, 2009, 06:57:43 PM
Rick, it should be quieter than the 100µF alone on the dc jack, am I right?!
Quiet and more stable - unregulated '12 volt' supplies can vary wildly upwards from 12 volts. You wouldn't want 17 volts across the heater right? That's a neat little circuit. However, I just use a single cap - but my power supply is very stable.
Yeah, I meant the 7812 and the cap on the dc jack...As I always do...
Aw man! I'm getting frustrated here!
I tried this circuit out (original valve caster) with a non center tapped ecc85 before and ran it at 6.3 volts and it worked out fine.
Had some problems with it lighting up like a lightbulb when running on 9/12 volts (go figgure)-
Now however i've got some brand new ecc82's and they light up like lightbulbs when i try to run the heaters on 9/12 volts in SERIES.. I do use pin 4 and 5 for power and I meassure about 8 ohms across pin 4 and 5 to pin 9 and about 16 ohms across pins 4 and 5 so it makes sense.. except it doesent work (works way to well rather).
I use a regulated powersupply that i've checked a dozen of times.
I guess the only thing that could do this would be if pin 9 was grounded but it's not.. I've checked and checked again.. acctualy concidering drilling the socket for pin 9 out.
??? :icon_cry: :icon_cry: :icon_cry:
I built a subcaster with 6111 tube using a V+ of 24 volts. More headroom for pedal steel and Telecaster guitar with high output pickups. I was looking for a clean sound to warm up the sound of my transistor amps. Tried several voltages on the breadboard, 12V, 18V, 24V and 33V. Liked 24V the best for my application. For the power supply I built a separate "brick" with 2 mouser trannies. Mounted 5 pin DIN connectors to the power supply and the pedal and use standard midi cable for power transmission. I think this setup might also work well with the previous schematics using 6021 submini tubes, but I don't have any and I haven't tried it. Links to pics and schematic below. Sorry but the gut shot is a little out of focus, but you can get the idea.
(http://img150.imageshack.us/img150/9761/24vsubcasterko5.th.gif) (http://img150.imageshack.us/my.php?image=24vsubcasterko5.gif)
(http://img234.imageshack.us/img234/9610/6111minitubegutnp1.th.jpg) (http://img234.imageshack.us/my.php?image=6111minitubegutnp1.jpg)
(http://img150.imageshack.us/img150/3668/6111minitubeboostlh4.th.gif) (http://img150.imageshack.us/my.php?image=6111minitubeboostlh4.gif)
Albot, I tried several different brands, every tube has its own light, going from a dim light to a bright light...So that shouldn't be a problem...I wonder why it doesn't work... ???
Sonbone, great work!!! I like your pedal, how's its sound?!
Sonbone, I agree, at about 20-22 volts you can start to hear what you would hope to hear from a vacuum tube circuit, if that makes any sense.
Mine light up with a bright glowing white/yellow light.. I think im simply cursed! :icon_evil:
So when i try to run only the heaters out of the circuit, 12 volts make the entire heater pipe glow orange since i've never seen that in pictures i guess it's bad.
Oh im so worried, irritated and frustrated! dont wanna break my new tubes!
Especally since I wouldn't learn anything from it except that im cursed.
Albot, the 12au7 is made to run the heaters at 12V - so don't worry about that...
This pedal sounds really smooth, adds quite a bit of warm to transistor amp. My computer with recorder is down right now, so I can't record samples. I have a version on my breadboard with both cathodes bypassed with 22uf caps and biased with 1.5K resistors. Gain control is through 500K pot between stages. It's similar to Real McTube. It has a much more aggressive sound since there isn't any negative feedback going to the cathodes. I like the circuit on the breadboard better with my stratocaster. Also sounds much better at 22V and above. Two reasons I settled on 24V. (1) 7824 voltage regulator in power supply filters better than just using rectifier and caps (which gives me about 33V with 24V ac transformer). (2) To me the circuit sounds best with volume control as close to wide open as possible. Above 24V the gain is so much that I really have to cut back the volume. I tried a voltage divider at output, as in Real McTube, but I don't really like that any better than just cutting back the volume.
hi guys ;D
been following this thread for a long time but only recently registered here so i could post. Anyway here are some pics of my dual valvecaster:
http://picasaweb.google.com/lh/photo/7TEglQRTtORH-XrPrAMSbA?feat=directlink (http://picasaweb.google.com/lh/photo/7TEglQRTtORH-XrPrAMSbA?feat=directlink)
http://picasaweb.google.com/lh/photo/8nKdyLj9lwrciY7mb7vyUw?feat=directlink (http://picasaweb.google.com/lh/photo/8nKdyLj9lwrciY7mb7vyUw?feat=directlink)
I'm running it at 18V and i've placed a jfet buffer before each valvecaster stage. I have loads and loads of questions for you guys but for now i leave only the pics :D
Hi there - I think I've seen it before - did you post it on other forums?
Only at forumusica.com it's a portuguese forum for musicians someone else did a valvecaster there too but nowhere else that i can recall.
I have to buy some more 12au7's so i can experiment with this circuit some more, there are loads of things that i'd like to try, using jfets as a ccs instead of the plate resistor, using voltage pumps so i can get more voltage using a standard 9v power supply, etc... I have loads of questions for all you guys but i have to gather my stuff before i go berserk here ;D
I will post some ideas i have in the next few days.
Quote from: intricatecode on January 12, 2009, 10:26:26 PM
Only at forumusica.com it's a portuguese forum for musicians someone else did a valvecaster there too but nowhere else that i can recall.
I have to buy some more 12au7's so i can experiment with this circuit some more, there are loads of things that i'd like to try, using jfets as a ccs instead of the plate resistor, using voltage pumps so i can get more voltage using a standard 9v power supply, etc... I have loads of questions for all you guys but i have to gather my stuff before i go berserk here ;D
I will post some ideas i have in the next few days.
Well I've used a PNP BJT as a CCS with a similar circuit, the effect is a little brighter and with some more gain:
http://www.diystompboxes.com/smfforum/index.php?topic=71864.0
Here I am using a MAX1044 voltage pump for higher voltage, but its an amp not a pedal - I'm still developing this idea. I will try it with a pedal eventually too:
http://www.diystompboxes.com/smfforum/index.php?topic=73317.0
The 12AU7 really opens up once you get past 20V DC. At 12V DC I find the sound is way to dark/bassy and compressed.
My latest 12AU7 tube project uses a B+ of 38V DC. Still want to try out something in the 60V DC - 100V DC range to see what it sounds like.
Hello y'all!
I'm gonna spend my very first post on this thread since I've read all the 40+ pages of this amazing project. It's very inspiring to see how a simple tube and a few resistors and caps can make that chunky distortion that I've been looking for a long time.
I think I'm on that guitarist 'phase' where you're looking for pure tone and eventually get rid of those multieffects that only give you headaches while trying to adjust a ton of parameters... Now I'm trying to keep things simple, and fortunately for my quest a pair of 12at7 tubes came into my hands while I was buying some stuff from stewmac.com ("tubes? why do you need a tube? I dunno... for 10 bucks maybe will look cool in some steampunk stuff").
So now I'm waiting for those tubes and very anxious to start the project. I'd really like to thank you all for sharing your knowledge and I hope that in the next few weeks you'll see my creation.
Regards,
Mario (mexico)
Quote from: frequencycentral on January 13, 2009, 02:18:36 AM
Quote from: intricatecode on January 12, 2009, 10:26:26 PM
Only at forumusica.com it's a portuguese forum for musicians someone else did a valvecaster there too but nowhere else that i can recall.
I have to buy some more 12au7's so i can experiment with this circuit some more, there are loads of things that i'd like to try, using jfets as a ccs instead of the plate resistor, using voltage pumps so i can get more voltage using a standard 9v power supply, etc... I have loads of questions for all you guys but i have to gather my stuff before i go berserk here ;D
I will post some ideas i have in the next few days.
Well I've used a PNP BJT as a CCS with a similar circuit, the effect is a little brighter and with some more gain:
http://www.diystompboxes.com/smfforum/index.php?topic=71864.0
Here I am using a MAX1044 voltage pump for higher voltage, but its an amp not a pedal - I'm still developing this idea. I will try it with a pedal eventually too:
http://www.diystompboxes.com/smfforum/index.php?topic=73317.0
I've been following your work for quite sometime ;) but i only have a bunch of j201 around so i went looking about on the web if it was possible to use a jfet as a constant current source and aparently it is possible but i haven't tested it yet because in the meanwhile i have been using my double valvecaster full time on my pedalboard ;D recording an album and playing it live.
Anyway here are a couple of links i found about CCS and tubes:
http://headwize.com/projects/cavalli2_prj.php (http://headwize.com/projects/cavalli2_prj.php) has an explanation on using jfets, mosfets, and other types of ccs with tubes
http://www.headphoneamp.co.kr/bbs/zboard.php?id=diy_sijosae&no=211 (http://www.headphoneamp.co.kr/bbs/zboard.php?id=diy_sijosae&no=211) comparison of performance of different kinds of ccs
I haven't come around to really explore the math and concept behind the usage of ccs's with the tubes but what appealed to me about using jfets is that you can do it with a lot less parts than with a bjt even though the performance may be less. From what i've read just tying the gate and source of a jfet will give you a ccs with the value of the jfets Ids. What this value should be to use with the valvecaster i haven't had the time to work out so far.
Regarding the voltage pumps i read somewhere that the icl7660 is more robust than the MAX1044 and is pin compatible and that the icl7660scpa version is less prone to give an audible "wine" when using it as a voltage pump.
I'm relatively new to electronics and diy effects pedals the double valvecaster was my first build so i still have a lot to learn about triodes fortunately this forum has been a great help so far and pages like this one http://www.aikenamps.com/CommonCathode.htm (http://www.aikenamps.com/CommonCathode.htm) have helped a lot about understanding how all of it works.
Right now i have to find the time to work out all the math in my head and review all my electronics concepts (it's been a few years since high school) so i can hopefully contribute with some ideas to :D
Quote from: intricatecode on January 13, 2009, 06:14:11 PM
Regarding the voltage pumps i read somewhere that the icl7660 is more robust than the MAX1044 and is pin compatible and that the icl7660scpa version is less prone to give an audible "wine" when using it as a voltage pump.
It's the other way aound - the 1044 has a frequency boost feature which the 7660 lacks. I have both in my stocks, and a MAX on the bradboard at the moment - I'll pull it and replace it with a 7660 and see if the whine is bad.
Thanks for the links!
Well I was feeling kind of bummed today and so i thought about getting out my trusted soldering iron and try out some of the ideas i had about using a J201 as a CCS on the valvecaster to clear my head.
Here's what i came up with:
(http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=38340&g2_serialNumber=1)
I used it on the last triode stage of the valvecaster running it at 18v and it made quite an audible diference.
The first thing i did was to use the J201 with the source and gate tied but it didn't work so well, so i thought about soldering a 20k pot between source and gate and wiggle it about to see if it made any difference. I found a sweet spot and using a switch compared the sound between the CCS and the standard 100k resistor and the CCS was quite a bit louder ;D
So then i measured the voltage difference on pin 6 between using the CCS and the 100k resistor, with the CCS i got about 15v and with the 100k resistor it was about 10v. I measured the resistance value of the pot and it was about 65 ohms, it stayed quite a bit louder up until 1k and after that started to get progressively quieter. When i went under the 65 ohms it started to sound weird and also quieter.
So there you have it folks :icon_mrgreen: now i'm happy as a camper with a louder valvecaster prototype on my hands and a couple of more ideas up my sleeve.
Please try it and tell me if this works for you too.
Only 5 posts and you come up revolutioning the Valvy... :icon_eek: Seems a good mod to do...After all, just a j201 and a res....
Gonna try out this one, I guess it won't be a distortion unit but a good clean preamp
(http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=38344&g2_serialNumber=2)
Where did you get this idea from?
I really doubt an EF86 pentode will run on 12V DC.
I just did the vero, I found the schem googling around (don't remember where)
I uploaded in my directory, just click --->HERE (http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=38346&g2_serialNumber=1)
Quote from: Renegadrian on January 15, 2009, 08:26:27 PM
I just did the vero, I found the schem googling around (don't remember where)
Hi!
Looks very familiar. I draw that schematic and post it in reply #478 (page 24) in this topic. If you found that schematic somewhere else than my page (http://www.tg-music.com) please tell me.
http://www.tg-music.com/EF86.pdf
Hi Elwood - pls PM or write here your complete name, so I can credit you on my layout (also check if I made any errors...) - I don't remember where I did find it, maybe you could try googling it and see for yourself - as you can see it's not the PDF you linked but a cut image of just the schematic.
How does it sound BTW?!
Quote from: Renegadrian on January 16, 2009, 05:18:36 AM
Hi Elwood - pls PM or write here your complete name, so I can credit you on my layout (also check if I made any errors...) - I don't remember where I did find it, maybe you could try googling it and see for yourself - as you can see it's not the PDF you linked but a cut image of just the schematic.
I had no luck with google. Need to try harder. ;D
Quote from: Renegadrian on January 16, 2009, 05:18:36 AM
How does it sound BTW?!
It's been five or so years when I build that. But if my memory serves me right, it's very clean, warm and maybe a bit "hi-fi". It does get better with higher voltage and good tube. I used old Tesla EF86. Alot better than new electro haromonix. Svetlana EF86 might be good new tube.
Yeah, I read that altough there are some guitar amp schems around, the EF86 is well known for being clean, so it's mainly used on phono preamps.
edit - I got 3 nos ef86, so they should sound good...I'll try it soon...
I was reading some docs, and this always helpful page here -->http://www.diystompboxes.com/pedals/tubedummy.html
Some pages ago we found we can raise R1 and R2 values, they are the first plate res. (pin 1) and the first grid leak res. (pin 2)
So I ask, would it be useful, asking for more gain, to raise the second plate res. (pin 6) and the second grid leak res. (pin 7) too?
The first cathode (pin 3) goes to ground thru the 50k gain pot and the second cathode (pin 8 ) directly to ground. I assume that if I omit the gain pot, so pin 3 to ground, I'd have max gain?!
Also, the heaters need 150mA - but what about the plate?! I read that in a class A amp at 100V the plate mA is 11.8...
how much current should the plates receive, at 12V and more?! will 30mA be enough?! I want to try it at higher voltages, up to 60V - I guess the polarized cap should have higher V value (not the ordinary 16V, but 35V or more?!)
Quotethe EF86 is well known for being clean
Maybe, but the EF86 has a good bit of gain, which is useful for driving a PI/output-stage. See the AC15, DC30, etc.
Quote from: DougH on January 20, 2009, 08:49:38 AM
Maybe, but the EF86 has a good bit of gain, which is useful for driving a PI/output-stage. See the AC15, DC30, etc.
True. One of my favourite amps was my "orange AD15" with EF86 preamp. Really nice OD-sound from PI. Shame I never completed that build. :-\
Quote from: Renegadrian on January 20, 2009, 08:42:12 AM
So I ask, would it be useful, asking for more gain, to raise the second plate res. (pin 6) and the second grid leak res. (pin 7) too?
Yes, raising the second plate resistor to say 470K will give a bit more gain, and raising the second grid leak resistor to 1M will too.
Quote from: Renegadrian on January 20, 2009, 08:42:12 AM
The first cathode (pin 3) goes to ground thru the 50k gain pot and the second cathode (pin 8 ) directly to ground. I assume that if I omit the gain pot, so pin 3 to ground, I'd have max gain?!
That is correct.
Quote from: Renegadrian on January 20, 2009, 08:42:12 AM
Also, the heaters need 150mA - but what about the plate?! I read that in a class A amp at 100V the plate mA is 11.8...
how much current should the plates receive, at 12V and more?! will 30mA be enough?!
Have a look at my "Murder One" (http://www.diystompboxes.com/smfforum/index.php?topic=73222.0) amp - I'm running the plates of one dual triode and one pentode from the 60 volt / 20ma output of the MAX1044.
Quote from: Renegadrian on January 20, 2009, 08:42:12 AM
I want to try it at higher voltages, up to 60V - I guess the polarized cap should have higher V value (not the ordinary 16V, but 35V or more?!)
Whatever voltage you run at you should use caps rated higher than that voltage, so for 60 volts you should be using caps rated at 63 volts, or 100 volts to be on the safe side.
OK Rick, after reading your precious post, I am sure that the link and schem I wanted to share could be useful for our tube projects...
check this out...
http://w1.859.telia.com/~u85920178/power/vconv_01.htm
you can have 30mA at 60V, with a circuit that's quite simple to assemble...I already begun, think I am gonna end it tomorrow...
Be sure I'll report it back! :icon_wink:
Quote from: Renegadrian on January 20, 2009, 01:28:34 PM
OK Rick, after reading your precious post, I am sure that the link and schem I wanted to share could be useful for our tube projects...
check this out...
http://w1.859.telia.com/~u85920178/power/vconv_01.htm
you can have 30mA at 60V, with a circuit that's quite simple to assemble...I already begun, think I am gonna end it tomorrow...
Be sure I'll report it back! :icon_wink:
Precious moi?
That's a very interesting schematic you linked to - very similar to the MAX schemo I'm using in many ways.
Yes, my friend...I saw that the max1044 is a little more expensive than 4 trannies (3 bc547 and 1 bc557), so I'd jump on this one if my experiment goes well...
My thanks to all, especially Rick for helping me debug my power supply probs for my stock Valvecaster. I took a cue from the "Murder One" schematic and I had some TC1044s (its an equivalent to a Max1044) around so while I had the whole thing disassembled I thought I'd drop it in and see if it would work. I only used one stage (2 diodes, 1 10uf cap to pin 2, and one to ground) of voltage boosting, and I went up from 12V to 21V. It definately made my pedal louder, and richer sounding. Maybe even less compressed, IMHO. Either way it sounded AWESOME! Just wanted to confirm that the voltage boost from a 1044 will work in pedal setting like the Valvecaster. Thank you!!!
I just built the Marsha Valve by Erik Hansen - altough he provided a vero layout too, I didn't like it and redrew it from scratch.
here it is...
(http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=38568&g2_serialNumber=3)
I am not so keen on hybrid circuits, but I wanted to try anyway, who knows...Actually it doesn't give that magic sound that a pure circuit like the Valvy can give...Too many components for a sound that's not so special...Also a well filtered PS is mandatory.
I personally don't like it that much...
Hi all :icon_smile:
First of all, thanks a lot for this precious thread & for your help. I'm a beginner in DIY and I've learn a lot by reading your messages.
So, here are few pictures of my "Valvecaster" :
* Circuit
(http://img149.imageshack.us/img149/2801/imgp0181mp7.jpg) (http://imageshack.us)
(http://img149.imageshack.us/img149/imgp0181mp7.jpg/1/w771.png) (http://g.imageshack.us/img149/imgp0181mp7.jpg/1/)
Nota : it's the first time that I draw & realized my own PCB because normally I order them in an electronic shop but it's very long & expensive :icon_rolleyes:
* Face Cover :
(http://img301.imageshack.us/img301/9594/imgp0179jd2.jpg) (http://imageshack.us)
(http://img301.imageshack.us/img301/imgp0179jd2.jpg/1/w747.png) (http://g.imageshack.us/img301/imgp0179jd2.jpg/1/)
Nota : I have to drill the enclosure
My "little" contribution to this projec :
PCB (size 75*25mm):
(http://img242.imageshack.us/img242/1163/pcbvalvecasterdim75x25mey5.gif) (http://imageshack.us)
(http://img242.imageshack.us/img242/pcbvalvecasterdim75x25mey5.gif/1/w602.png) (http://g.imageshack.us/img242/pcbvalvecasterdim75x25mey5.gif/1/)
Based on this layout :
(http://img242.imageshack.us/img242/2053/nouvelleimage1qn4.png) (http://imageshack.us)
(http://img242.imageshack.us/img242/nouvelleimage1qn4.png/1/w625.png) (http://g.imageshack.us/img242/nouvelleimage1qn4.png/1/)
who became :
(http://img132.imageshack.us/img132/6551/renderkn9.gif) (http://imageshack.us)
(http://img132.imageshack.us/img132/renderkn9.gif/1/w701.png) (http://g.imageshack.us/img132/renderkn9.gif/1/)
Nota : S1-> Input Caps switch / S2 -> Resistors Switch / S3 -> Capacitors Switch
Questions : What kind of switches have you used for thoses because I tink that I haven't used the good one (For S1 I took a DPDT and for S2&S3 I took DPDT) ? :icon_redface:
Cheers,
Taya
Taya, (http://www.smileys.it/images/smileys_it_2202.gif) and thx for your contribution to the thread - it's so much apreciated from a newcomer - and hell that graphic rules...Tell me more about those mods, are they so useful?
Hi Renegadrian & thank you for your Welcome (we are neighbour because I'm French)
So I've found that schem' on a pdf file found somewhere in those thread, & I've worked on it for having a PCB because I doensn't like to used "drilled sheet"
I've just finished the wiring yesterday evening, so I prefer finish the project before giving my opinion on it :icon_wink:
Ok, I think I have gone through most of this stuff. One quick question...I want to build one of these and I can see I'm gonna need to run a power supply with it. Can you guys reccomend a cheap 9 or 12 volt regulated power supply (wall wart)? I run batteries on my pedals so I don't want to have to buy an expensive unit like a PP2. Surely somebody makes a nice cheap 12 volt source.
Thanks,
Dan
Check out the 1spot 12v powersupply. You can get it at MF and other similar sites and stores. If it's anything like their 9v, it will be very clean.
Finally I got my tubes from stewmac.com, I bought a pair of 12AT7, which I expect they sound neat.
I also spend a hard time on finding 12AU7 locally but I finally got 4 from a small repair center (the last four tubes in the whole city!), so I think it would be a great project to build a 2-channel valvecaster with one of each tubes.
But first things first...I'm building the basic Valvecaster, but I have some sort of questions before I start the project this weekend:
1) I couldn't find/get a tube base, so I must solder the parts (or wires) directly to the tube pins... Is there a problem if I do this? I've never treated with tubes, so I don't know if my soldering iron would damage it. I have decent skills on soldering, but this is new to me.
2) I've read few pages back that changing the input cap to a lower value would decrease the bassy or boomy sound of the v'caster. I'm pretending to use a cap selector with a rotary switch, but I'm concerned about how many caps and their values... any suggestions?
Thank you all!
Hi guys!
I have been reading all the pages for the last week and must say you guys are great, lots of info.
I have made a bunch of different circuits and etched several boards, but never anything with tubes!
So much to learn and understand LOL.
Anyway I have most of the parts ready for a twin Valve-caster, just waiting for the Russian tubes to show up.
I'am going to install the new board right into my Amp.
It's a 1981 Univox U65G 50 watt solid state amp.
Hoping to use 30volts at the plate and 12v at the heaters.
Heres a link to an easy to understand site on how a tube works and biasing.
http://www.tubedepot.com/whisbipo.html
Quote from: castillogm on February 04, 2009, 02:24:11 PM
1) I couldn't find/get a tube base, so I must solder the parts (or wires) directly to the tube pins... Is there a problem if I do this? I've never treated with tubes, so I don't know if my soldering iron would damage it. I have decent skills on soldering, but this is new to me.
I wouldn't do that - you'll have a hard time mounting the tubes to the enclosure without sockets. And what if you need to change a tube? They shouldn't be too heat sensitive though. Better to get some sockets - try ebay.
Quote from: castillogm on February 04, 2009, 02:24:11 PM
2) I've read few pages back that changing the input cap to a lower value would decrease the bassy or boomy sound of the v'caster. I'm pretending to use a cap selector with a rotary switch, but I'm concerned about how many caps and their values... any suggestions?
0.033 or 0.022 will be less bassy.
What do you think about putting a cap across VR1? Apparently it will help to increase the gain.
It would go between pin 3 and the ground.
Glen
OK I have the Twin Valvecaster board etched and ready to be drilled . It's been a couple of years since I made one, had to re figure out how to do it :icon_rolleyes:
The two tube sockets will not be mounted to the board.
(http://i107.photobucket.com/albums/m297/biggy-boy/twincasterboard.jpg)
Glen
Quote from: frequencycentral on February 08, 2009, 06:53:21 AM
Quote from: castillogm on February 04, 2009, 02:24:11 PM
1) I couldn't find/get a tube base, so I must solder the parts (or wires) directly to the tube pins... Is there a problem if I do this? I've never treated with tubes, so I don't know if my soldering iron would damage it. I have decent skills on soldering, but this is new to me.
I wouldn't do that - you'll have a hard time mounting the tubes to the enclosure without sockets. And what if you need to change a tube? They shouldn't be too heat sensitive though. Better to get some sockets - try ebay.
Quote from: castillogm on February 04, 2009, 02:24:11 PM
2) I've read few pages back that changing the input cap to a lower value would decrease the bassy or boomy sound of the v'caster. I'm pretending to use a cap selector with a rotary switch, but I'm concerned about how many caps and their values... any suggestions?
0.033 or 0.022 will be less bassy.
Thanks, Freq! I started the project this weekend, and I used some sort of connectors to attach'em to the tube while I find a socket. For my disgrace, I didn't get nothing but a terrible hum. The tube was lit, but no sound came out... I hope I come with better news next week.
COOL got my twin Valvecaster working
I got my first ever DIY tube preamp working, it sounds good!
I built it into my 50 watt solid state amp. The amp was way to clean, could not get any overdrive or distortion on it before adding the twin Valvecaster.
But now it's got tons of overdrive :icon_mrgreen: :icon_mrgreen:
I didn't bother adding the out put volume control but I think I'll add it in.
Thanks guys for all the great info. I would not have been able to make the preamp without this thread!
Glen
I'm sure this has been covered but I couldn't find it. I want to build a valvecaster running off 9v using a subminni 6111 tube, of which I have 40, as opposed to a 12AU7, of which I have one, and it is being used. The pinouts are different, yes? what changes do I need to make?
Quote from: svstee on February 14, 2009, 05:06:27 PM
I'm sure this has been covered but I couldn't find it. I want to build a valvecaster running off 9v using a subminni 6111 tube, of which I have 40, as opposed to a 12AU7, of which I have one, and it is being used. The pinouts are different, yes? what changes do I need to make?
(http://i210.photobucket.com/albums/bb292/frequencycentral/SubCaster-2.gif)
But you can use a 9 ohm / 1 watt resistor to drop your 9 volts to 6.3 volts for the heater instead of using the LM317 arrangement. A 10 ohm / 1 watt resistor would give you 6 volts, which is still within the tubes spec.
OK need some help with grounding.
I'd like to improve the grounding on my printed circuit boards.
I want to start using ground planes to help reduce noise.
To go one step further Id' like to have two ground planes. One audio signal GND plane and one power GND plane.
I've included a schematic (not mine)
Can someone point out which grounds in the schematic are audio signal GNDs and which ones are power GNDs?
(http://i107.photobucket.com/albums/m297/biggy-boy/TwinPeaksSchematic2-1.jpg)
Thanks
Glen
Read RG's star grounding article over at http://www.geofex.com it has all the info your looking for.
Quote from: Jered on February 16, 2009, 08:35:49 PM
Read RG's star grounding article over at http://www.geofex.com it has all the info your looking for.
Hi Jered thanks for the link
Lots of great info on that site. I book marked it!
Yup well aware of the star ground principle.
I'm looking for different info thou.
I want to take it further and separate the signal grounds and the power grounds in a tube circuit. tubes are new to me and I'm trying to learn what portions of the circuit is power and what is signal. Ground planes are large areas of copper on a printed circuit board used as a common ground point the star. So I'm looking at basically having
two ground planes (stars) on the circuit board. One for power GNDs and one for signal GNDs. The two planes are then joined with a trace and then to the chassis.
I just need help figuring out what the GND points are in the diagram I posted.
My guess would be:
signal GND R1, R3, R6, R8, pot 4
power GND pot 1, pot 2 and all the GNDs connected to the cathodes.
Glen
hey everybody,
any news on a current working tubecaster project with a EF86?
I'm highly interested in soundsamples, bugs, issues, suggestions and so on with this one.
I'm planning to get myself a 48V DC power adapter to have higher anode voltage and get the 6.3V with the usual LM***
thoughts on that?
alternatively I thought about getting more voltage from a wall wart with this schematic:
(http://forum.musikding.de/vb/attachment.php?attachmentid=2332&d=1233246454)
help is mucho appreciated,
greetings from hamburg, germany
Hallo schlendrian from Renegadrian and (http://www.smileys.it/images/smileys_it_2202.gif)
I only know about this EF86 project, not a Valvy based one...
(http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=38344&g2_serialNumber=2)
The image you tried to post don't show - try to post it again
I used a voltage multipier, so I'd go with a common wall wart at 12V, a 7812 or 7806 for the heaters and the multiplier (the one I build gives out 50V)
hey there! yeah I saw that schematic recently which got me pretty excited about this project.
since the EF86 would sound significantly better and would've had more distortion with more voltage I thought about a power plug with already
48V 0,5A directly to the plate and then generate the 6.3V for the heating, can I do that with a 7806 as described in the schematic you posted?
would be this one:
(http://i63.photobucket.com/albums/h151/eisen-uli/guitar/48Vnetzteil.jpg)
here is the alternative with a 6V wal wart transforming the voltage up to about 200V for the plate:
(http://i63.photobucket.com/albums/h151/eisen-uli/guitar/attachment-1.gif)
Pollin is a special shop over here, so don't worry about the numbers. :D
what do you think about it?
Hi
You had mentioned about dropping the voltage from 48 volts to 6.3 using a regulator!
from 48v to 6.3v would be asking alot from one regulator. It would need a big heat sink to dissipate the heat coming off of it, plus I think they have a voltage max of 40V.
I guess you could put a resistor in series with the regulator to create a voltage drop. But it would have to be able to also handle the heat it would need to shed. 3 or 5 watts??
Glen
Quote from: biggy boy on February 17, 2009, 12:54:25 PM
I guess you could put a resistor in series with the regulator to create a voltage drop.
Glen
213.5 ohm / 8.54 watt @ 200ma
To use a voltage drop resistor to drop 42.7 volts (48 - 6.3) it would have to be 213.5 ohm / 8.54 watt. That would be one huge resistor. Does such a resistor exist even?
42.7 / 0.2 = 213.5 (ohm)
42.7 x 0.2 = 8.54 (watt)
I think when dropping this much voltage you should be thinking transformer.
Quote from: frequencycentral on February 17, 2009, 01:06:36 PM
Quote from: biggy boy on February 17, 2009, 12:54:25 PM
I guess you could put a resistor in series with the regulator to create a voltage drop.
Glen
213.5 ohm / 8.54 watt @ 200ma
To use a voltage drop resistor to drop 42.7 volts (48 - 6.3) it would have to be 213.5 ohm / 8.54 watt. That would be one huge resistor. Does such a resistor exist even?
42.7 / 0.2 = 213.5 (ohm)
42.7 x 0.2 = 8.54 (watt)
I think when dropping this much voltage you should be thinking transformer.
If you put the resistor in-front of a regulator you would not have to drop the voltage down to 6.3v just drop it down to say 12 volts feeding the regulator.
You would still need a heat sink on the reg. 48 -12 = 36 / .2 = 180 ohm 36 x.2 = 7.2 watts LOL it would still be a big ass resisitor.
Glen
Quote from: frequencycentral on February 17, 2009, 01:06:36 PM
That would be one huge resistor. Does such a resistor exist even?
Quote from: biggy boy on February 17, 2009, 01:19:29 PM
LOL it would still be a big ass resisitor.
Second item from the bottom, 220 OHM 10 WATT 10% CERAMIC BLOCK RESISTOR-SIZE: 1-7/8"L x 3/8"H x 3/8"D @ $2.50, http://www.electronicplus.com/content/ProductPage.asp?maincat=RE&subcat=REG
Something else to take into consideration.
Manufactures usually rate their power supply voltage output at there full amp rating. The voltage at no load and at half the specified max load would be higher.
This should be considered when selecting the size of the resistor. The open no load voltage I would guess to be someware around say 52 volts or maybe a bit more??
With a 200 ma load and the load of the tube. the voltage would still be higher then the 48 volts.
Glen
Help!
I've followed the schematic located in the first post or on beavis' page (the normal one, not the pcbless, etc) to the letter in my implementation of the valvecaster. Discovered a few issues like the gain pot being wired the wrong way round (yes, following the schematic visually, how lazy of me) and the same for the tone pot, both of which have been fixed.
The main problem is that I don't hear much difference in sound. In fact, with the pedal engaged at full volume and gain, the output volume is softer. It's so much softer that putting my gain pot slightly below full will result in no sound. From my understanding of the schematics, even if the volume pot happened to have been reversed, it would make no difference to the sound.
All resistors and solderpoints have been checked. I can't check the caps but I trust em. Except..... For axial electrolytic caps, the arrow points from +ve to -ve right? I always have doubts when it comes to caps.
I have slight hum when I put the wires connected to the tube socket so close together but other than that, it's fine.
I need help! It's unholy for a overdrive pedal to sound softer than it's bypass!
Quote from: firethorn on February 20, 2009, 11:26:49 AM
Help!
I've followed the schematic located in the first post or on beavis' page (the normal one, not the pcbless, etc) to the letter in my implementation of the valvecaster. Discovered a few issues like the gain pot being wired the wrong way round (yes, following the schematic visually, how lazy of me) and the same for the tone pot, both of which have been fixed.
The main problem is that I don't hear much difference in sound. In fact, with the pedal engaged at full volume and gain, the output volume is softer. It's so much softer that putting my gain pot slightly below full will result in no sound. From my understanding of the schematics, even if the volume pot happened to have been reversed, it would make no difference to the sound.
All resistors and solderpoints have been checked. I can't check the caps but I trust em. Except..... For axial electrolytic caps, the arrow points from +ve to -ve right? I always have doubts when it comes to caps.
I have slight hum when I put the wires connected to the tube socket so close together but other than that, it's fine.
I need help! It's unholy for a overdrive pedal to sound softer than it's bypass!
Please post voltage sfrom each pin of you tube!
Measure from the pin to ground right? Sorry.. Relatively new to this but getting the hang of it.
Pin 1 to ground is 9.2V
Pin 5 to ground is 9.2V
Pin 6 to ground is 4.8V
The rest are at 0V? Supposed to measure from Vref to these pins?
Quote from: firethorn on February 20, 2009, 09:46:31 PM
Measure from the pin to ground right? Sorry.. Relatively new to this but getting the hang of it.
Pin 1 to ground is 9.2V
Pin 5 to ground is 9.2V
Pin 6 to ground is 4.8V
The rest are at 0V? Supposed to measure from Vref to these pins?
It would be nice to see voltages at all 9 pins. Here's mine, running at 12 volts, with the gain control set to maximum:
Pin 1: 3.02v
Pin 2: -0.518v
Pin 3: 0.00v
Pin 4: 0.00v
Pin 5: 11.97v
Pin 6: 8.21v
Pin 7: -1.285v
Pin 8: 0.00v
Pin 9: 5.91v
As you are running at 9 volts, all your voltages will be 25% less than mine. Your voltage at pin 1 is much too high, it should be 25% of the power supply voltage, so you do have a problem around that pin, perhaps the resistor value is wrong or you have a short? Also, what power supply are you using? Is it filtered/regulated? What voltage does it supply? What is its
ma capability? The arrows on an electrolytic cap point to it's negative side.
Here is a question for you folks. Will a 5964 tube work in this apllication? I know it is a 7 pin and I would have to change the pinouts, but would it work? I only ask becasue I have a few of them and I may try building it with it instead.
http://tdsl.duncanamps.com/show.php?des=5964 (http://tdsl.duncanamps.com/show.php?des=5964)
Dan
Quote from: Big Dan on February 21, 2009, 08:54:28 AM
Here is a question for you folks. Will a 5964 tube work in this apllication? I know it is a 7 pin and I would have to change the pinouts, but would it work? I only ask becasue I have a few of them and I may try building it with it instead.
http://tdsl.duncanamps.com/show.php?des=5964 (http://tdsl.duncanamps.com/show.php?des=5964)
Dan
With that particular tube both the cathodes are connected, so you would have to tie pin 7 to ground, ditch the Valvecaster gain control and instead have an interstage gain control in place of the second stage grid resistor.
Also bear in mind that the heater is 6.3v / 450ma, so you will need to drop voltage for the heater with resistor ( 13 ohm / 3 watt @ 12 volts, or 6 ohm / 2 watt @ 9 volts should do the trick) or voltage regulator (7806 or LM317)
http://frank.pocnet.net/sheets/127/5/5964.pdf
Wow, thanks for the informative reply. I guess I will stick with a 12AU7 for my first go around. Maybe after that I'll try something different.
Dan
Quote from: frequencycentral on February 21, 2009, 07:24:23 AM
Quote from: firethorn on February 20, 2009, 09:46:31 PM
Measure from the pin to ground right? Sorry.. Relatively new to this but getting the hang of it.
Pin 1 to ground is 9.2V
Pin 5 to ground is 9.2V
Pin 6 to ground is 4.8V
The rest are at 0V? Supposed to measure from Vref to these pins?
It would be nice to see voltages at all 9 pins. Here's mine, running at 12 volts, with the gain control set to maximum:
Pin 1: 3.02v
Pin 2: -0.518v
Pin 3: 0.00v
Pin 4: 0.00v
Pin 5: 11.97v
Pin 6: 8.21v
Pin 7: -1.285v
Pin 8: 0.00v
Pin 9: 5.91v
As you are running at 9 volts, all your voltages will be 25% less than mine. Your voltage at pin 1 is much too high, it should be 25% of the power supply voltage, so you do have a problem around that pin, perhaps the resistor value is wrong or you have a short? Also, what power supply are you using? Is it filtered/regulated? What voltage does it supply? What is its ma capability? The arrows on an electrolytic cap point to it's negative side.
Actually I meant the rest are at 0V. The resistors are correct. Probably a short.. Weird though.
Am using a 1spot think it's v2. Puts out "9V". ~9.2-9.4 when measured without load. It's regulated and can put out 1.5A. SMPS but very well filtered.
With this information in hand(esp the sample values) I can now try to troubleshoot it myself. Will post back once I get something.
Thank you very much for your reply. Most people don't realise that even the simplest things can spark off a chain reaction for someone else in the direction of self discovery. =D. Again, thanks. =)
Retested the resistors and noticed that R2 was coming up at 0R. Switched it out and it worked. Weird though that when I measured it before, it read correct. Not the "I could've sworn it was correct" situation, but the "I know what I saw" kind. Very odd.
Pedal is lovely. Can't seem to tell much difference when using a 12ax7 or the 12ay7 though. Will have to try it out on a bigger amp probably.
Thanks so much for the help frequency central. I've fixed my pedal and I've learnt about a half a dozen new things.
Cheers,
firethorn.
Quote from: firethorn on February 23, 2009, 06:47:41 AM
Retested the resistors and noticed that R2 was coming up at 0R. Switched it out and it worked. Weird though that when I measured it before, it read correct. Not the "I could've sworn it was correct" situation, but the "I know what I saw" kind. Very odd.
Pedal is lovely. Can't seem to tell much difference when using a 12ax7 or the 12ay7 though. Will have to try it out on a bigger amp probably.
Thanks so much for the help frequency central. I've fixed my pedal and I've learnt about a half a dozen new things.
Cheers,
firethorn.
No problemo! Glad you got it debugged and working, and glad to have been some help. I found this awesome forum via this particluar thread less than a year ago, I have learned so much, so it's good to give some back. :icon_biggrin:
Man, this thing sounds great! Thanks a lot for such a wonderfull and easy project. Great project for "tube-starters".
Hi everybody,
I'm still looking for modifying my Valvecaster & I would have a little technical question about this :
I know that "Heater power Voltage" is around 12V under 150mA but I would like to know how to mesure "plate voltage" ?
Thank's for your help
Taya
plate voltage is just what it sounds like. If you measure the voltage between the plate of a triode (pin 6 or pin 1 on a 12AU7) to ground, that is your "plate voltage". Now, when most people talk about a particular plate voltage they're really talking about the plate voltage at idle (no signal applied to the input of the circuit). The plate voltage is primarily affected by the power supply voltage, the plate resistor, the cathode resistor and the transconductance curve of the triode. Another interesting voltage to check is the cathode voltage. This dictates the bias point of your tube (assuming you're using a self-biasing scheme).
Thanks a lot for your help :icon_mrgreen:
hey everyone!
i'm a newbie and i'm having trouble with this simple box.
here are voltages:
pin1 - 8.91v
pin2 - 0.40v
pin3 - 0.00v
pin4 - 0.00v
pin5 - 9.12v
pin6 - 9.02v
pin7 - 0.27v
pin8 - 0.00v
pin9 - 4.36v
my wallwart is 9.12v
any ideas?
Quote from: dcd666 on February 27, 2009, 04:10:42 PM
hey everyone!
i'm a newbie and i'm having trouble with this simple box.
here are voltages:
pin1 - 8.91v
pin2 - 0.40v
pin3 - 0.00v
pin4 - 0.00v
pin5 - 9.12v
pin6 - 9.02v
pin7 - 0.27v
pin8 - 0.00v
pin9 - 4.36v
my wallwart is 9.12v
any ideas?
Here's mine, running at 12 volts, with the gain control set to maximum:
Pin 1: 3.02v
Pin 2: -0.518v
Pin 3: 0.00v
Pin 4: 0.00v
Pin 5: 11.97v
Pin 6: 8.21v
Pin 7: -1.285v
Pin 8: 0.00v
Pin 9: 5.91v
As you are running at 9 volts, all your voltages will be 25% less than mine. Your voltage at pin 1 is much too high, it should be 25% of the power supply voltage, so you do have a problem around that pin, perhaps the resistor value is wrong or you have a short? Your pin 6 voltage is also far too high, it should be about 70% of the supply voltage, check the value of the plate resistor at pin 6 and check for shorts.
i've replaced both resistors: R2 & R3 and it's still the same.
voltages on pin1 and 6 are much too high.
i've followed by this schem:
http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=32777&g2_serialNumber=3
any ideas what i'm doing wrong?
i'll try to post some photos later.
edit:
here are photos:
(http://img253.imageshack.us/img253/9683/s5000020.th.jpg) (http://img253.imageshack.us/my.php?image=s5000020.jpg) (http://img89.imageshack.us/img89/3130/s5000022.th.jpg) (http://img89.imageshack.us/my.php?image=s5000022.jpg)
Have ye triplequad checked that all the resistors are functioning with an ohmeter?
yep.
General Note after playing with a new 12AU7 pre-amp all day on the breadboard....
Increase grid leak resistors from 720K - 1M5 for a brighter clearer sound. Wont be as boomy and dark. Don't go too high, the affect will be minimal and those large value resistors are noisy. I think you can go as high as 22M though, that's if your plate current does not exceed 5mA.
ok. now it works. it was just a matter of bad wallwart.
but i can't figure out how to put a DPDT with LED into it... (i don't need a true bypass).
can you help with it?
by the way - it's nice a sounding box :)
http://www.geofex.com/tektips.htm
Right at the btm, stomp switch wiring
bypass works just fine but still i can't add a LED indicator to it :icon_sad:
Use a stereo input jack. The method where the effect can't be turned on unless there's a jack plugged in the input.
Just finished my Valvecaster build, stuck an Electro Harmonix LPB in front of it for a very effective kick that takes the pedal into nice heavy overdrive territory. Really pleased with the build, thanks Beavis and thanks Renegadrian for the vero layout. Here's my take on the whole "relic" thing applied to pedals;
(http://i395.photobucket.com/albums/pp31/mothercruncher/Guitar%20Pedal%20Builds/pic_top.jpg)
(http://i395.photobucket.com/albums/pp31/mothercruncher/Guitar%20Pedal%20Builds/pic_inside.jpg)
Hey that's a great pedal! I am glad I have a part in it in some way... :icon_redface: :icon_surprised:
I like it!!!
Whats the trimpot do Mr. Landgraff? ;)
Quote from: kurtlives on March 11, 2009, 07:14:23 PM
Whats the trimpot do Mr. Landgraff? ;)
Looks like it's the LPB's volume. Like the distressed look!
Looks good man!
Has anyone been using shielded cable in the signal path?
I've been using RG174/u between the input jack and pin1, pin 7 and the output jack.
But I'm wondering if it's really needed? It's a pain in the a$$ to work with.
Any thoughts?
Glen
I wouldn't bother. Its not the kind of circuit that really would benefit much from coax cable.
Id regulate your heaters and give them stiff filtering and move on with it and play!
Ok thanks
I'm almost done this build, its the second Valvecaster.
This one will be running at 140 volts.
I'm using the Real McTube transformer setup.
Glen
hey there
i've recently built a valvecaster, but i'm having a few problems, after building the circuit and testing it it didnt work, the valve lights up and i hear a hum the volume knob seems to be working cus it cuts the hum, the tone knob when its all the way down also cuts the hum, and the gain seems its not working, i checked the connections to see if any where missplaced or soldered together, i know there is alot of possibilities of what could be wrong, but if anyone has an idea it would be apreciated
i'm new in electrinics and i know little about it i'v tried this has my first project so please take it easy on me :icon_wink:
Quote from: archaon13 on March 14, 2009, 02:19:39 PM
hey there
i've recently built a valvecaster, but i'm having a few problems, after building the circuit and testing it it didnt work, the valve lights up and i hear a hum the volume knob seems to be working cus it cuts the hum, the tone knob when its all the way down also cuts the hum, and the gain seems its not working, i checked the connections to see if any where missplaced or soldered together, i know there is alot of possibilities of what could be wrong, but if anyone has an idea it would be apreciated
i'm new in electrinics and i know little about it i'v tried this has my first project so please take it easy on me :icon_wink:
Hi, good that the valve lights up! The hum would be a power supply issue - tubes are choosy. What power supply are you using? Is it filtered/regulated? What voltage does it supply? What is its ma capability? You may be able to solve the hum by using a 7812 (search this thread) and a 100uf cap across the power rails, or by using a good filtered/regulated power supply. The gain not working suggests maybe you wired the pot wrong? Does your guitar signal pass through the effect at all?
It would be nice to see voltages at all 9 pins. Here's mine, running at 12 volts, with the gain control set to maximum:
Pin 1: 3.02v
Pin 2: -0.518v
Pin 3: 0.00v
Pin 4: 0.00v
Pin 5: 11.97v
Pin 6: 8.21v
Pin 7: -1.285v
Pin 8: 0.00v
Pin 9: 5.91v
If you are running at 9 volts, all your voltages will be 25% less than mine.
Quote from: frequencycentral on March 14, 2009, 03:19:42 PM
Quote from: archaon13 on March 14, 2009, 02:19:39 PM
hey there
i've recently built a valvecaster, but i'm having a few problems, after building the circuit and testing it it didnt work, the valve lights up and i hear a hum the volume knob seems to be working cus it cuts the hum, the tone knob when its all the way down also cuts the hum, and the gain seems its not working, i checked the connections to see if any where missplaced or soldered together, i know there is alot of possibilities of what could be wrong, but if anyone has an idea it would be apreciated
i'm new in electrinics and i know little about it i'v tried this has my first project so please take it easy on me :icon_wink:
Hi, good that the valve lights up! The hum would be a power supply issue - tubes are choosy. What power supply are you using? Is it filtered/regulated? What voltage does it supply? What is its ma capability? You may be able to solve the hum by using a 7812 (search this thread) and a 100uf cap across the power rails, or by using a good filtered/regulated power supply. The gain not working suggests maybe you wired the pot wrong? Does your guitar signal pass through the effect at all?
It would be nice to see voltages at all 9 pins. Here's mine, running at 12 volts, with the gain control set to maximum:
Pin 1: 3.02v
Pin 2: -0.518v
Pin 3: 0.00v
Pin 4: 0.00v
Pin 5: 11.97v
Pin 6: 8.21v
Pin 7: -1.285v
Pin 8: 0.00v
Pin 9: 5.91v
If you are running at 9 volts, all your voltages will be 25% less than mine.
thanks for the relply
the values on the power supply is 9vdc 800ma, but i dont think thats the only problem (if its a problem), the bypass signal works but wen i turn it on i only ear the hum and no guitar signal, the gain potenciometer i have has an off switch forgot to mention that, i simply didnt connect anything to the other two pins it had (could that be the problem?)
i've tried to mesure the pins on the valve but i dont know how lol
Quote from: archaon13 on March 14, 2009, 03:52:18 PM
thanks for the relply
the values on the power supply is 9vdc 800ma, but i dont think thats the only problem (if its a problem),
Is it regulated/filtered?
Quote from: archaon13 on March 14, 2009, 03:52:18 PM
the gain potenciometer i have has an off switch forgot to mention that, i simply didnt connect anything to the other two pins it had (could that be the problem?)
If it's the type with a switch grafted on the back it souldn't be a problem. Did you have a look at the Valvecaster wiring diagram on Dano's site? Second diagram down: http://www.beavisaudio.com/projects/ValveCaster/
Quote from: archaon13 on March 14, 2009, 03:52:18 PM
i've tried to mesure the pins on the valve but i dont know how lol
You have a multimeter? Set it to 'volts'. Clip the black lead to ground somewhere, and clip the red lead to each pin of the tube in turn. Note down your readings for each pin. If you don't have a mulitmeter you could use your tongue and estimate - but a multimeter is more accurate! :icon_mrgreen: Might also be a good idea to check that you're giving the circuit the correct polarity from the power supply, if ground reads -9 volts you have it reversed.
Quote from: frequencycentral on March 14, 2009, 04:44:38 PM
Is it regulated/filtered?
my newbish prevents me from understanding how to see that lol sorry
Quote from: frequencycentral on March 14, 2009, 04:44:38 PM
If it's the type with a switch grafted on the back it souldn't be a problem. Did you have a look at the Valvecaster wiring diagram on Dano's site? Second diagram down: http://www.beavisaudio.com/projects/ValveCaster/
i did it's wired that exact same way only with a true bypass switch
Quote from: frequencycentral on March 14, 2009, 04:44:38 PM
You have a multimeter? Set it to 'volts'. Clip the black lead to ground somewhere, and clip the red lead to each pin of the tube in turn. Note down your readings for each pin. If you don't have a mulitmeter you could use your tongue and estimate - but a multimeter is more accurate! :icon_mrgreen: Might also be a good idea to check that you're giving the circuit the correct polarity from the power supply, if ground reads -9 volts you have it reversed.
i have a multimeter only its analogic when i trie to mesure the first pin, the needle tries to go down so i cant read any of the pins, the few that move the needle makes it go down, could it be reversed has you said?
I just tried a 12v power supply I have laying around and the humming stoped!
but still no signal from the guitar to the amp
Quote from: archaon13 on March 14, 2009, 05:21:17 PM
i have a multimeter only its analogic when i trie to mesure the first pin, the needle tries to go down so i cant read any of the pins, the few that move the needle makes it go down, could it be reversed has you said?
Yup, sounds reversed. Test the polarity of the power supply - the 'protocol' for effects pedals is centre=ground, most wall warts (yours too?) are the reverse of that.
the polarity symbol on the power suply is this (http://wombatula.com/electronics/polarity.png)
Thats the opposite of effects pedal protocol. You can cut off the power supply lead and solder it on the other way around, using electrical tape to make good and isolate the wires from each other. The tube probably won't have suffered any damage - they're tough cookies.
Also bear in mind that if you have a metal chassis DC socket you will need to isolate it form your (metal) enclosure, or the positive will short against it.
i have a socket with a little holder in metal, i'm presuming that doesnt make contact with the tube circuit or am i wrong?
Quote from: archaon13 on March 14, 2009, 06:33:52 PM
i have a socket with a little holder in metal, i'm presuming that doesnt make contact with the tube circuit or am i wrong?
If the chassis is plastic and just the nut is metal then thats fine.
Guys i have been following this thread for a while and i really want to make my own valvecaster, but over here a tube is like 60$ a single tube T_T .... Is it really worth it? :P if so, i'll build one :icon_biggrin:!!!
PD: 1000 Posts on this thread :o :o :o :o
Its a cool unit, I would never pay $60 for a new stock tube though. Well fro a generic 12AU7...
Why not order from another coutntry or a cheaper source?
its almost impossible to order anything from outside in venezuela :P.... the sources ive found are these ....
http://www.audiopormenos.com/tubos-de-vacio.html... it reads for a 6l6 "179 bs." the ratio to a dollar is 2,15... so 179/2,15 is 80$!! i realize its a power tube and probably preamp tubes are cheaper. But still is way too expensive =/ thats the only sourve ive found here :(
Edit: Just so you see how big of an overprice here... a big muff for around 200$
Waky, send me your address in a PM
Quote from: Jered on March 15, 2009, 04:51:02 AM
Waky, send me your address in a PM
Jered, you're a saint...you know why... :icon_wink:
Just found this on istructables, seems interesting...thought it should have its place in this topic...
The ValveLiTzer: Low-voltage Tube Booster (http://www.instructables.com/id/The_ValveLiTzer_Low_voltage_Tube_Booster/)
(http://www.instructables.com/files/deriv/FQH/EREV/FQ6EBKK7/FQHEREVFQ6EBKK7.MEDIUM.jpg)
Quote from: frequencycentral on March 14, 2009, 07:11:13 PM
If the chassis is plastic and just the nut is metal then thats fine.
fixed! i used a new power supply and it works!
thanks for your help
has soon has i put it in the case i'l post some pics
just one thing the overdrive kinda fries how can i make it less fried?
Quote from: Jered on March 15, 2009, 04:51:02 AM
Waky, send me your address in a PM
Pm sent!!, Are ya from venezuela too?
Renegadrian: Did you build that Valvelitzer?, How does it sound?.
No, I didn't build it, just found it googling around...
----------------------------------------------------------------
I have to report my breadboard experiment with the Valvy...I used the voltage multiplier (http://w1.859.telia.com/~u85920178/power/vconv_01.htm) I built (I got up to 56V with an unregulated 12V wall wart)
Let me tell you that this simple circuit just breathes a new life with the added voltage...I'd reccomend everyone the voltage mult. I built, it's so easy and so useful with those tube project (as I started my own experiment, the TUBE STAR being my first creation!) - Also it's even cheaper than the 1044 circuit...
does that voltage doubler works well with tubes supplying so little current? (probably a noob question but iv'e never built anything tubey :icon_razz:)
It provides enough current to make a tube work good...(actually it is a multiplier, not just a doubler...)
I built some tube stuff, and that VM gave me good results on every of them I tried it on...(Valvy, Tube Star, Pentaboost...)
OMG! Two nights, a lot of coke, a bunch of tree branching into other articles, schematics, random links, and material price searching later and I'm done reading through pretty much every post in this thread! Learned a bunch of stuff! I think I may have to give one of these a shot! I'm thinking the Pentabooster up front, the Twin-Caster setup, and maybe a diode clipping setup at the end with a toggle for a boost switch.
You guys think a booster after the 'Caster section would be needed for the clipping? I read in the thread somewhere about it being needed because of the clipping lowering the signal, but would the Penta, and Twins be enough to not need it (Just a little volume tweaking)?
Also, if anyone is interested, I have a text file with what I considered to be the good info from the thread. I can copy, and paste it if wanted. It's a bit long though lol.
Quote from: Altec on March 17, 2009, 06:37:11 AM
OMG! Two nights, a lot of coke, a bunch of tree branching into other articles, schematics, random links, and material price searching later and I'm done reading through pretty much every post in this thread! Learned a bunch of stuff! I think I may have to give one of these a shot! I'm thinking the Pentabooster up front, the Twin-Caster setup, and maybe a diode clipping setup at the end with a toggle for a boost switch.
You guys think a booster after the 'Caster section would be needed for the clipping? I read in the thread somewhere about it being needed because of the clipping lowering the signal, but would the Penta, and Twins be enough to not need it (Just a little volume tweaking)?
Also, if anyone is interested, I have a text file with what I considered to be the good info from the thread. I can copy, and paste it if wanted. It's a bit long though lol.
So how many litres of cola did you get through? I think diode clipping would be a bit of a shame, the Valvecaster has plenty of gain and crunch anyway, good tube clipping - so why add clipping diodes? Having said that, you could make it a switchable option for more tones. Try some Ge diodes, they will clip sooner and smoother, or have switchable Ge/Si. There should be enough volume/boost available for you not to need any booster after the diodes. Build a Pentaboost as a seperate pedal, then you can use it where you want - does sound good before the Valvecaster though.
Quote from: frequencycentral on March 17, 2009, 01:27:03 PM
Quote from: Altec on March 17, 2009, 06:37:11 AM
OMG! Two nights, a lot of coke, a bunch of tree branching into other articles, schematics, random links, and material price searching later and I'm done reading through pretty much every post in this thread! Learned a bunch of stuff! I think I may have to give one of these a shot! I'm thinking the Pentabooster up front, the Twin-Caster setup, and maybe a diode clipping setup at the end with a toggle for a boost switch.
You guys think a booster after the 'Caster section would be needed for the clipping? I read in the thread somewhere about it being needed because of the clipping lowering the signal, but would the Penta, and Twins be enough to not need it (Just a little volume tweaking)?
Also, if anyone is interested, I have a text file with what I considered to be the good info from the thread. I can copy, and paste it if wanted. It's a bit long though lol.
So how many litres of cola did you get through? I think diode clipping would be a bit of a shame, the Valvecaster has plenty of gain and crunch anyway, good tube clipping - so why add clipping diodes? Having said that, you could make it a switchable option for more tones. Try some Ge diodes, they will clip sooner and smoother, or have switchable Ge/Si. There should be enough volume/boost available for you not to need any booster after the diodes. Build a Pentaboost as a seperate pedal, then you can use it where you want - does sound good before the Valvecaster though.
First, let me say: Thank you Rick! Your contributions to this thread have been great, and I love your tube designs!
If I had to guess, I'd say 2 liters a night. Wasn't as bad as I thought now that I think about it! The diode clipping was more of a "Why not" for me. I'm forever playing with different settings on my amp, and my parametric EQ, so more options the better! :icon_biggrin:
Thanks for the info man! Guess I gotta put together a shopping list!
i'v heard that ceramic caps arent very good for sound is that true?
I get hiss when I use them.. Supposed to take out the rf buzz but i get more.. bah...
Don't rememner if I already posted it...
Jon Anderson Lonewolf (http://jonanderson.mn.googlepages.com/tubebooster)
(http://jonanderson.mn.googlepages.com/schematic.jpg)
Anyway, as the sound clip was so interesting, I got this on my breadboard, and man, it's so good...I run it at more than 50V with my voltage multiplier and with some tweakings...
220 plate res.
47k instead of the 50k res
47k at the input
33µF at cathode cap
22nF instead of 10nF at the output
Also I like to put a pot to the cathode cap, I don't know if it can be conventionally done, but hey it just sets the gain!
----------------------------------------------------------------------------
EDIT - I have to report another success in the submini field - I found those 6205 I bought some months ago on the bay soooooooo good in the above schematic, just mind the different pinout...
I am going to experiment a little with those little pentodes...Let's see...
here comes mine valvecaster:
(http://img18.imageshack.us/img18/7773/s5000002.jpg)
works really nice.
big thanks goes to Adriano for his help.
WOW Pavel, I love the way it turned out - I am glad if I helped you somehow... :icon_redface:
Simple but nice to the eyes - I am sure it's good to the ears too, isn't it?! :icon_wink:
don't be so humble Adriano :icon_wink:
oh yeah it's very good.
i've had some problems with power supply but i coped with it.
all the parts used were recovered from old radio, stompboxes, etc.
i haven't spent even a penny :icon_biggrin:
that's why it looks how it looks... :icon_smile:
Thanks for the link Renegadrian! The sound clips sound good! This is definitely one that I want to build also.
Just a quick question, is there a connections next the 68K resistor and the 150K variable resistor (where the red circles are)?
(http://i215.photobucket.com/albums/cc70/tr-stompboxes/axe-boxes/6au6.jpg)
Quote from: tranceracer on March 22, 2009, 07:19:49 AM
Just a quick question, is there a connections next the 68K resistor and the 150K variable resistor (where the red circles are)?
I would say no there are not. Also consider making the 50K screen resistor a higher value, and having a cap to ground from the screen.
Quote from: frequencycentral on March 22, 2009, 07:26:17 AM
Quote from: tranceracer on March 22, 2009, 07:19:49 AM
Just a quick question, is there a connections next the 68K resistor and the 150K variable resistor (where the red circles are)?
I would say no there are not. Also consider making the 50K screen resistor a higher value, and having a cap to ground from the screen.
The Screen cap to ground where does it go? on the left side of the resistor ( between the screen and resistor ) or the right side of the resistor?
Also can I use a EL84?
Glen
Quote from: biggy boy on March 22, 2009, 09:19:33 AM
Quote from: frequencycentral on March 22, 2009, 07:26:17 AM
Quote from: tranceracer on March 22, 2009, 07:19:49 AM
Just a quick question, is there a connections next the 68K resistor and the 150K variable resistor (where the red circles are)?
I would say no there are not. Also consider making the 50K screen resistor a higher value, and having a cap to ground from the screen.
The Screen cap to ground where does it go? on the left side of the resistor ( between the screen and resistor ) or the right side of the resistor?
Also can I use a EL84?
Glen
Left side, have a look at my Pentaboost, which is similar: http://www.diystompboxes.com/smfforum/index.php?topic=70524.0
Thanks Rick! :D
Updated schemo:
(http://i215.photobucket.com/albums/cc70/tr-stompboxes/axe-boxes/6au6-2.jpg)
Yeah, that's it, the suppressor and the cathode go togheter - the input goes to the grid and the output has no connection with the screen.
Basically pentodes share the same schematic (I studied some in the last days, like mark lavelle's you can see at his site http://www.harmonicappliances.com/index.html (http://www.harmonicappliances.com/index.html)) and every schem I saw has that screen cap.
I tried to put one in, but it's not so mandatory, you can just try but it sounds good without, so I wouldn't bother...
You can have a 220k instead of that strange 150k (a 150k pot?!) and you can surely play around raising that screen res.
If you want more gain, put an electro cap at the cathode, say 33µF, maybe tied to a small value pot, 1k-10k.
Just finished building this and I only get a clean boost when the effect is engaged ?? There's no overdrive sound whatsoever. I used this layout:
http://www.aronnelson.com/gallery/main.php/v/Schematics-etc/Valvecaster-no-tone.jpg.html
I can hear a 'difference' if you know what I mean. The signal is definately passing through the tube.
Any ideas ??
Don't know, man, that layout is verified by myself and other people too...Check the voltages and compare them to the ones posted by Rick a couple of pages ago...Also, check back every connection on every pin, and maybe the res. values, maybe you got one wrong?!
I'm running this off 9v. Would that affect the effect ??
Quote from: 1878 on March 23, 2009, 11:37:15 AM
I'm running this off 9v. Would that affect the effect ??
Sorry
1878, I can't help you until you change your avatar! Why would anyone come from Liverpool and support 'the other team' as they are referred to in my house?
Seriously though, you should be getting some nice dirt at 9 volts, but as Adriano says, post your voltages, check your resistor values and solder connections.
Rick
Q: How many 'Liverpool' supporters does it take to change a lightbulb ??
A: 5... 4 to change the lightbulb and one to make sure they all get back to Bristol safely.
You should have more respect for your parent.
I'll check and post the voltages tomorrow. All componant values are correct, the valve heats up/glows but no overdrive. I bought a JJ Tesla ECC82 which I'm hoping will do the job. Volume control works as does the gain, it's just there's no gain to control :(
Maybe you inverted the tube pins?!
http://www.dogstar.dantimax.dk/tubestuf/pinout.htm (http://www.dogstar.dantimax.dk/tubestuf/pinout.htm)
Luckily for me, the pins are numbered on my socket. Made my first foray into tubes a bit easier !! Here's my voltages using a well filtered 9v power supply:
1: 7.03
2: -0.15
3: 0.01
4: 0.00
5: 9.20
6: 8.05
7: -0.15
8: 0.00
9: 4.61
Hmmm.....
Thanks again.
Those are the voltages Rick posted of his Valvy some pages ago - As you can he runs it at 12V so some values are to be a little higher.
Pin 1: 3.02v
Pin 2: -0.518v
Pin 3: 0.00v
Pin 4: 0.00v
Pin 5: 11.97v
Pin 6: 8.21v
Pin 7: -1.285v
Pin 8: 0.00v
Pin 9: 5.91v
What it differs too much is the voltage you get at pin 1 - post the value of the res. wired to the plate.
The resistor is 220k and the capacitor is 0.047uf (47nf) which are correct to the layout. Just checked all the other values and they're also correct. I've double checked the wiring/soldering also. Everything seems fine.
I'm getting a nice sparkly valve boost but no overdrive.
Yup, your pin 1 should be 25% of the power supply voltage - about 2.3v in your case.
Your pin 6 should be 66% of the power supply voltage - about 6 volts in your case.
This seems to be a common debug problem with Valvecasters - the plates being too high.
Those voltage of mine that Adriano posted were taken with the gain set to maximum (ie first stage cathode grounded) by the way.
If you are sure everything is correct (though it can't be if your voltages are off), you could replace the 220K resistor with a 1M pot (use the pot's lugs 1 and 2) and tweak it until you read about 2.3v at pin one. Then measure the resistance between lugs 1 and 2 of the pot. Do the same with the 100K at pin 6, though I think pin 6 will come into line when you sort out pin 1.
For those of you who want to try (or have tried with poor results) a 12AX7 in your Valvecaster, I have some ideas.........
12AU7 is a medium mu dual triode
6111 (Subcaster) is also a medium mu dual triode
12AX7 is a high mu dual triode
6112 is also a high mu dual triode
I just breadboarded a Subcaster using a 6112 in place of a 6111 - blarty due to too much gain, so I experimented with a couple of resistor values and would recommend:
For a 12AX7 Valvecaster: change R2 to 100k, change R4 to 100k.
For a 6112 Subcaster: change R5 to 100k, change R6 to 100k.
I haven't got any 12AX7 to try this with, but I'm assuming that a 12AU7 is roughly equal to a 6111, and a 12AX7 is roughly equal to a 6112, based on mu.
I've got an idea for a new very dirty high gain tube pedal based on my little experiments with 6112 (should work well with 12AX7 too), it's working title is "Promiscuous Girlfriend" - watch out for the thread!
ok Rick, I'll try that one tomorrow! :icon_wink:
Altough my tries with the Tube Star went nowhere with the AX...
Quote from: dcd666 on March 20, 2009, 02:00:00 PM
here comes mine valvecaster:
(http://img18.imageshack.us/img18/7773/s5000002.jpg)
works really nice.
big thanks goes to Adriano for his help.
Hey dcd666. I like that enclosure you used. Where did you get it?
i'm glad that you like it.
enclosure was an old amp switch made by polish manufacturer KODA.
now it's called EXAR but i think they don't produce these enclosures anymore.
Hey there guys :) I made a valvecaster and sadly... I don't think I made it correctly :D
All i get when I turn the volume/gain is a brrmmmmm. No sound from guitar, just brm...... The tube filaments light up and stuff, and gets hot. I think they may be running at a higher voltage .... anyways... any1 got a PCB layout and PnP version? I just can't debug with hanging layouts ;(
Quote from: tednet on March 26, 2009, 01:54:23 PM
Hey there guys :) I made a valvecaster and sadly... I don't think I made it correctly :D
All i get when I turn the volume/gain is a brrmmmmm. No sound from guitar, just brm...... The tube filaments light up and stuff, and gets hot. I think they may be running at a higher voltage .... anyways... any1 got a PCB layout and PnP version? I just can't debug with hanging layouts ;(
Huh? PNP transistors? not tubes?
press n peel stuff. toner transfer pcb. not transistors ofc :D
Ohhh i see!
I use a laser printer and print on ink jet glossy photo paper. Then use a hot cloths iron and heat it onto the board, then soak it in hot water to peel the paper away.
Glen
no no no, you still got me wrong :D
I was wondering if any1 has a PCB for toner transfer + the PCB layout for this project. I tried building it normally, with the provided layout and I failed. Now, I can't debug it cuz I am only used to debugging pcb projects. Also it's too chaotic this way :S
Quote from: tednet on March 26, 2009, 06:36:46 PM
no no no, you still got me wrong :D
I was wondering if any1 has a PCB for toner transfer + the PCB layout for this project. I tried building it normally, with the provided layout and I failed. Now, I can't debug it cuz I am only used to debugging pcb projects. Also it's too chaotic this way :S
define failed.
didn't have a 220k resistor, so I wired a few old russian resistors (from around 1970s)... anyways, all I get is brmmmm. The guitar signal doesn't go out the amp and well the tube gets ultra mega hot, I burned myself on it ;(
That is why I am asking for a pcb version, so I can make it properly :D
Quote from: tednet on March 27, 2009, 11:46:01 AM
didn't have a 220k resistor, so I wired a few old russian resistors (from around 1970s)... anyways, all I get is brmmmm. The guitar signal doesn't go out the amp and well the tube gets ultra mega hot, I burned myself on it ;(
That is why I am asking for a pcb version, so I can make it properly :D
Quote from: tranceracer on March 29, 2008, 03:20:45 PM
Well here's my little contribution to this awesome thread. :D
Here's a smaller PC board for this cool little pre. I've used it and verified that it works. Haven't hooked up the voltage divider section but it should work too.
The trace and components are exactly mirrored so, fold on the line and iron the trace and components on the PC at the same time.
This is 300dpi image.
(http://i215.photobucket.com/albums/cc70/tr-stompboxes/MatsumiTubeVertPinsTrace.jpg)
(http://i215.photobucket.com/albums/cc70/tr-stompboxes/MatsumiTubeVertPinsTraceDetail.jpg)
Quote from: Chawk on April 10, 2008, 03:32:27 PM
(http://chawk.files.wordpress.com/2008/04/trurl_pagecontent2.jpg)
(http://chawk.files.wordpress.com/2008/04/trurl_pagecontent-12.gif)
gee thanks man :) I saw those, guess I'll make them
Oh and I just realized my mistake... I wired everything while looking on the wrong side of the socket....
Quote from: tednet on March 27, 2009, 03:17:02 PM
gee thanks man :) I saw those, guess I'll make them
Oh and I just realized my mistake... I wired everything while looking on the wrong side of the socket....
That'll get ya every time. :icon_biggrin:
bleh I am getting even more confused >.< Do those numbers show the pins of the tube, or the pins of the socket >.<
1 is pin 1 of the tube, the pcb posted is like having the tube glass point pointing at you.
Here is a vero layout I did for the subcaster, can anyone verify it? Schematic found here.
http://www.diystompboxes.com/smfforum/index.php?topic=66746.0
(http://i301.photobucket.com/albums/nn71/svsguitarhero/DIY%20My%20layouts/Subcaster10.gif?t=1238195003)
I'm using a resistor instead of the LM317 setup, and the tube is oriented like this:
1 8
2 7
3 6
4 5
Thanks!
I'll check it tomorrow, too tired now...Well, my eyes are, my ears not, so I am playing with the TRIODE TRIODE and with JERED 6021 HIGH GAIN - I like them both, built them some time ago and forgot them...Give them a try!!!
The second is more on the bass side, but has more gain, while the first is a good medium gain overdrive...
Quote from: svstee on March 27, 2009, 07:06:06 PM
Here is a vero layout I did for the subcaster, can anyone verify it? Schematic found here.
(http://i301.photobucket.com/albums/nn71/svsguitarhero/DIY%20My%20layouts/Subcaster10.gif?t=1238195003)
The 14 ohm should be 18 ohm / 2 watt. The 470K can just be 1/4 watt. You have also missed the 100K plate resistor at pin 8.
I did this perf layout for another forum member some while ago, you could take just the part you need and ignore the LM317 bit. It's not verified, but I think it's correct. The layout is designed to mount inside an enclosure like how I did my Pentadriver and Vintage Vibe, if you know what I mean.
(http://i210.photobucket.com/albums/bb292/frequencycentral/Subcaster2.gif)
Wow, don't know how I missed the resistor.
I think the resistor should be 14 or 15 ohms though, since I'm running this at 9v, that gives me 6.4v and 6v, respectively.
I meant for the three watt resistor to be R1. Why do you say it only needs to be two? What is the current of this?
Quote from: svstee on March 27, 2009, 08:21:43 PM
I think the resistor should be 14 or 15 ohms though, since I'm running this at 9v, that gives me 6.4v and 6v, respectively.
Why do you say it only needs to be two? What is the current of this?
OK, for 9 volts then:
6111 heater: 6.3v / 300ma
Voltage drop required: 2.7v
2.7 / 0.3 = 9 (ohms)
2.7 x 0.3 = 0.81 (watts)
So a 10 ohm / 1 watt resistor will give you 6 volts @ 300ma. Thats an easy value to find and within the tolerance of the heater. :icon_biggrin:
Ah, I was doing my math wrong! I had to find for the needed drop. That makes way more sense. Thank you much.
How about this
(http://i301.photobucket.com/albums/nn71/svsguitarhero/DIY%20My%20layouts/Subcaster11.gif?t=1238202065)
Hi! Regarding the Valvecaster...I m thinking about breadboarding it and use the Beginner-Project-Boost circuit in front to make the tube really drive (or any other boost circuit if I might find one I like more ;) ) as soon as I get a 12AU7. What woul you say? Does it make sense? Will afford a couple of changes/additions of course, but thanks to the breadboard^^
Altough I like to go TUBE all the way, I did find a Tillman a good addition to the Valvy - It stays quite clear and doesn't add too much gain. So it boosts the tube in a "natural" way.
Rick finds a LPB a good addition, I tried but didn't like it, as Valvy is on the bass side and LPB too...
Try some booster and see what suits best for your ears. I'd suggest you Tillman - DOD 210 (labelled wrong in the gallery 201) - EA booster (first stage of the tremolo)
Yeah alright...maybe gotta fatten the signal a bit for my like...
but:
http://www.aronnelson.com/gallery/main.php/v/DRAGONFLY-LAYOUTS_0/album14/album143/DOD_201_JFET_PREAMP_VERO_001.gif.html?g2_imageViewsIndex=1 what does the red square with the red dot mean? its a cut connection line I guess?
Yes, a break in the line
Can anyone take a look at my layout? I tried building it last night without success and I want to make sure I'm working off a correct layout.
Quote from: svstee on March 28, 2009, 11:37:38 AM
Can anyone take a look at my layout? I tried building it last night without success and I want to make sure I'm working off a correct layout.
Your revised layout looks ok. But check that your breaks in the strips are actually 100% breaks - electrons only need a tiny connection too small for you to see with the naked eye. It's a common problem with stripboard, one reason I don't like the stuff. Use a continuity tester to determine this.
I do, and I also use a jeweler's loupe to check.
I found my mistake, I messed up on parts positioning. Thats what happens when you build at 1:30a.m. I guess.
Glad to know the layout looks good, I'll report back if I can get this working.
Well I fixed it (C3 was going from 10a to 10b instead of from 10a to 10c) but now I am running into quite an interesting problem. The 10 ohm resistor does nothing. I'm getting the full 9.16v on pin 3, and that probably killed my tube as well. I've tested the resistor, 10.2 ohms, I replaced the resistor and it still does the same thing.
What is going on?
Sounds like it isn't drawing the current you think it is.
Bu its the exact same voltage as my power supply, so I doubt it. It seems like I have a short somewhere, but I measured with my DMM, and there is 10r between the 9.16v and pin three, which also reads 9.16v.
Quote from: svstee on March 28, 2009, 02:21:00 PM
Bu its the exact same voltage as my power supply, so I doubt it. It seems like I have a short somewhere, but I measured with my DMM, and there is 10r between the 9.16v and pin three, which also reads 9.16v.
Mystifying. I'm sure my calculation for the voltage drop resistor is correct. It could be a short. Have you any other way to derive the heater voltage? Like a LM317? I wonder if it would be possible to use a number of 1n4148 in series to drop the voltage........each one has a voltage drop of 0.7v if I recall. So four in series would drop 2.8 volts. Never tried it..........I wonder if it would work?
Hmmm, I like the 1n4148 idea. Do you think I destroyed my tube by running it with 9v on pin 3?
Quote from: svstee on March 28, 2009, 02:31:43 PM
Do you think I destroyed my tube by running it with 9v on pin 3?
Probably not. They are tough little @#$%ers. You may have reduced it's life a little though. I once accidentally ran 12 volts through a 6111 heater without destroying it.
Wow, good to know. I'm going to go try that diode thing, I'll let you know if it works.
btw: where`s Stephane slajeune (http://www.diystompboxes.com/smfforum/index.php?action=profile;u=766;sa=showPosts) these days?
Hey Rick, can you link to the datsheet for the 6111 and 5672? I can't seem to find them.
Edit: Nevermind, I found them.
Got a 5672, and two 12AU7's on order. :icon_biggrin: If I like it enough, I may build a power amp, and build myself a practice amp! :icon_biggrin:
i just ordered the parts yesterday and hopefully i will get what i need, although i think i might have gotten a couple things wrong, i guess we will find out. it sucks since i cant find a decent components store anywhere in San Diego. anyone have any suggestions?
Quote from: KorovaMilkBar on March 28, 2009, 05:35:55 PM
i just ordered the parts yesterday and hopefully i will get what i need, although i think i might have gotten a couple things wrong, i guess we will find out. it sucks since i cant find a decent components store anywhere in San Diego. anyone have any suggestions?
EBay is a good source for parts, I get stuff all the time from Canadian dealers.
Glen
thanks for the advice, fortunately i went to Fry's electronics today and they had just about everything i need. i just need the mono audio jacks and some sort of ac jack. i did get a universal ac adapter that has a connector that resembles a 9v battery so i might just throw in a battery jack instead. the radioshack by my house should have some mono jacks in by tuesday so i just need to grab that and the battery jack and the tube i ordered should be in by then. so ya! hopefully i will have all the parts and get started by next weekend. once im done and if it turns out good i will definitely post pictures!
Alright, I got my layout working.
(http://i301.photobucket.com/albums/nn71/svsguitarhero/DIY%20My%20layouts/Subcaster11.gif?t=1238202065)
A couple problems with it, however.
1: Heater voltage is 5.96v, datasheet says 6.0v to 6.6v. Am I close enough? All I had were 10.7 Ohm 7 watt resistors.
2: Gain control does nothing.
3: I have less gain and slightly less treble with this than I do with my 12AU7 Valvecaster (no tone control version).
Any help would be appreciated.
Quote from: svstee on March 30, 2009, 08:03:11 PM
1: Heater voltage is 5.96v, datasheet says 6.0v to 6.6v. Am I close enough? All I had were 10.7 Ohm 7 watt resistors.
That's close enough I think! What's 0.04v between friends? The Subcaster was designed to run at 12 volts, so you're on new ground running it at 9 volts. I suspect you might have to experiment with the plate resistors, maybe sub them for pots and see if you can dial in the appropriate value? You should also be aware that 6111 will show very different voltages to 12AU7 using in the same circuit.
I was expecting I'd have to tweak a few things running it at 9v, (I had to for the pentaboost) but the fact that the gain pot has NO affect makes me think it might be more than that.
Oh well, I need more practice with a breadboard anyways.
Check your gain pot it might be faulty.
Clearly the pot has some resistance as if it didnt the tube would not work as it would not have a bias reference point. It could be shorted and going right to ground, this would provide a mu-follower and the circuit would work. Is there a lot of gain though, if so the cathode is going straight to ground.
It's hard to tell whats going on from your vero layout. The tubes are unclear.
Tube is the same way Rick does his, like this
(http://i210.photobucket.com/albums/bb292/frequencycentral/Subcaster2.gif)
Quote from: svstee on March 27, 2009, 07:06:06 PM
I'm using a resistor instead of the LM317 setup, and the tube is oriented like this:
1 8
2 7
3 6
4 5
Thanks!
One other thing. Why not use a 6.2v Zener diode? You can buy ones rated at 500mA for peanuts. This curcuit only draws 300mA, right? wouldn't work for all the submini stuff, but a cheap, easy and safe alternative for others. No clue why I just now thought of it.
http://cgi.ebay.com/50-pcs-Zener-Diodes-500mW-6-2V-5-Axial-Motorola-HQ_W0QQitemZ300304216297QQcmdZViewItemQQptZLH_DefaultDomain_210?hash=item300304216297&_trksid=p3286.c0.m14&_trkparms=66%3A2|65%3A15|39%3A1|240%3A1318
I haven't been able to get my Valvecaster build to work properly. It's got plenty of clean boost, but no overdrive. I'm putting an order in for parts tonight, so I'll get a couple of new pots etc and re-build the thing from scratch.
Also, I'm thinking of putting in a voltage doubler to boost it to 18v. Would there be any probs in this ??
Hey guys........I've been eyeing this project for months now, and just recently I got my hands on a 120v > 9v transformer. if I flip it, I can crank out 120v from a 120v>9v wallwart. Now I know that the 12--7 tubes like these values a lot more, so I was wondering if any of you know where I can find a project like that, OR how can I Mod this guy to make it run off of 120v.
ohh yeah, I would heat the heaters from the 9v coming from the wallwart.......smart or not?
I know very little about trafos, anyway I read somewhere you should be able to turn the trafo the other way around and get a good voltage - I believe it should be something less of the specified value, but no less than 100V in your case.
I also feel that you should somehow turn that AC into DC (is it mandatory, is it a better or it just doesn't matter?)
Also, sure you have a 9V (AC?) for the heaters (while 12V would be surely best)
I don't think there are mods to be applied at the main schem - I run mine at 50V - just apply the V at the plates...(pins 1 and 6)
The only problem I see is that you might not have enough juice in your wallwart (but then again you might). Your heaters will need a few hundred ma and then you have to remember that if you need 10 ma for your plates (not likely) with a 10:1 winding ratio, you will need at least 100 ma from your wallwart. I would recommend a fairly high powered zener for the regulation from 9V down to 6.3V.
Tubes must run on DC.
The 9V AC when rectified will be 12.7V so that is fine for series wiring of the heaters. Add some filtering and regulation and your set!
Your transformer setup will work fine as long as you put 9V AC onto the 9V side of the transformer.
The plate resistors and cathode resistors will need to be altered with the increased voltage. Cant say where to, I would experiment on the bread board first.
you guys are great! thanks a ton for the prompt responses.......I'm guessing that SSrectifier would be used, so that the heater can be used in the 12v config. also, I believe I would leave the tone and volume sections the same, while the plate resistors would need to be changed to something calculated from ohm's rule, right? How about the Gain pot, does that stay? I would also add something like an ssrectifier at the 120v section going to the plates and maybe a few large caps to filter............does it all sound correct?
Quote from: 703224796 on March 31, 2009, 05:10:25 PM
Hey guys........I've been eyeing this project for months now, and just recently I got my hands on a 120v > 9v transformer. if I flip it, I can crank out 120v from a 120v>9v wallwart. Now I know that the 12--7 tubes like these values a lot more, so I was wondering if any of you know where I can find a project like that, OR how can I Mod this guy to make it run off of 120v.
ohh yeah, I would heat the heaters from the 9v coming from the wallwart.......smart or not?
I'm running mine well with 157 volts and just a couple of resistor size tweaks
Two transformers back to back in 120 volt/ 12 volt---- 12volt/120volt out rectified it's boosted to 157 volts
Glen
hello! i just got a package from mouser and i messed up on the potentiometers. they are 1 b50k and 2 b100k (the plans call for a100k). they are also the receding (sp) thumbdial kind. so are these any good or should i head to radioshack? thanks!
mike.
p.s. i should be getting the tube anyday now, soon as i do i will be working away on this! im so excited!
Sorry to drag this up agian, but can I use a 6.2v Zener diode for the heater? Wouldn't work for all the submini stuff, but a cheap, easy and safe alternative for some.
http://cgi.ebay.com/50-pcs-Zener-Diodes-500mW-6-2V-5-Axial-Motorola-HQ_W0QQitemZ300304216297QQcmdZViewItemQQptZLH_DefaultDomain_210?hash=item300304216297&_trksid=p3286.c0.m14&_trkparms=66%3A2|65%3A15|39%3A1|240%3A1318
Quote from: svstee on April 04, 2009, 12:27:34 PM
Sorry to drag this up agian, but can I use a 6.2v Zener diode for the heater? Wouldn't work for all the submini stuff, but a cheap, easy and safe alternative for some.
http://cgi.ebay.com/50-pcs-Zener-Diodes-500mW-6-2V-5-Axial-Motorola-HQ_W0QQitemZ300304216297QQcmdZViewItemQQptZLH_DefaultDomain_210?hash=item300304216297&_trksid=p3286.c0.m14&_trkparms=66%3A2|65%3A15|39%3A1|240%3A1318
Are you still planning to un your Sub @ 9 volts? If so, you only need to drop 2.4 volts. That zener would drop 6.2 volts - ie. too much. Did you try 4x 1n4148 yet?
I did, they melted. I thought a zener ALLOWS 6.2v to pass? The Crowther Audio Hotcakes has an 8.7v zener right off the DC jack if I remember correctly.
Quote from: svstee on April 04, 2009, 12:40:56 PM
I did, they melted.
Heheehe - my favourite experiments are the ones involving melting/fuming components! At least now we know. :icon_biggrin:
Quote from: svstee on April 04, 2009, 12:40:56 PM
I thought a zener ALLOWS 6.2v to pass? The Crowther Audio Hotcakes has an 8.7v zener right off the DC jack if I remember correctly.
Dunno, never used zeners.
Zeners can be implemented to either drop their voltage or supply their rated voltage. In series, a zener will drop its rated voltage. If you stick it with the anode to ground, you will get their rated voltage at the cathode (this is how reference voltages are created, typically). that is why I love zeners. Also, you can get beefy 5W ones or bigger so that would handle subminis no problem, though you may have to glue them with thermal epoxy to the case or chassis for heatsinking.
Why would I need 5w? If I'm doing the math right, I only need around .9 watts. 1 watt should be fine, right?
1 watt will work, you might want a heatsink. I only mentioned 5W because if you try to run multiple tubes, you need big ratings. It was just a number.
Quote from: svstee on April 04, 2009, 04:44:25 PM
Why would I need 5w? If I'm doing the math right, I only need around .9 watts. 1 watt should be fine, right?
A good rule of thumb whenever designing tube electronics of anything with HV or heat...double you power ratings. If a plate resistor could be 1/4W double it up to 1/2W. 0.9W is too close to 1W for me...
Quote from: KorovaMilkBar on April 01, 2009, 11:41:07 PM
hello! i just got a package from mouser and i messed up on the potentiometers. they are 1 b50k and 2 b100k (the plans call for a100k). they are also the receding (sp) thumbdial kind. so are these any good or should i head to radioshack? thanks!
mike.
p.s. i should be getting the tube anyday now, soon as i do i will be working away on this! im so excited!
anyone????
The taper will be off, which means the adjustment will seem a bit choppy and hard to find the sweet spot. You can still use them, but if you can afford it, I would suggest getting the right ones because that will just make life easier.
OK, I was comparing my 6111 to my 12au7 vavlecaster and noticed that the 6111 has quite a bit more bass. the 12au7 had plenty, so I'm a little concerned. Any way to get a hair less bass out of it? Also the 6111 doesn't break up as early unless you have a guitar with very hot pickups or some kind of boost in front of it. I assume this a result of running a 12v circuit at 9v, but what would I change to improve this (beside running it at 12v)?
With tubes there is no real substitute for more voltage. In terms of bass, you can change the input and output caps. I built a tube booster with a .01 input and .047 output and that seemed to regulate the bass. Also look at any cathode bypass caps, lower values will reduce the bass.
I believe lowering the value of the cap between the two stages will also roll of some bass too.
Glen
That is true, I guess I just lumped that with either the output or input cap because it is the output of one stage and input of the other. You can also do some parallel resistor/capacitor things to tailor the frequency response between stages as well.
Found THIS (http://music-electronics-forum.com/showthread.php?t=12281) googling...
http://www.dogstar.dantimax.dk/tubestuf/graphics/dz_tone.gif
http://www.triodeel.com/comp1.jpg
Quote from: Renegadrian on April 06, 2009, 04:14:02 PM
Found THIS (http://music-electronics-forum.com/showthread.php?t=12281) googling...
JKowalski is a member here too, surprised he hasn't mentioned it on this thread too. Innovative use of a charge pump to up the plate voltage!
This circuit looks too good to be true! I'd like to try it out with this tube:
http://tdsl.duncanamps.com/show.php?des=6J6A
I will be running off of proper heater voltage. What I'd like to know is, since the plates of the two triodes are connected, can I connect the cathode of the second tube to the gain pot instead of ground?
Also, are there any parameters in the datasheet I missed that would prevent it being used for audio or for low voltage?
Quote from: CynicalMan on April 06, 2009, 05:36:44 PM
This circuit looks too good to be true! I'd like to try it out with this tube:
http://tdsl.duncanamps.com/show.php?des=6J6A
I will be running off of proper heater voltage. What I'd like to know is, since the plates of the two triodes are connected, can I connect the cathode of the second tube to the gain pot instead of ground?
Also, are there any parameters in the datasheet I missed that would prevent it being used for audio or for low voltage?
The plates are not internally connected, but the cathodes are. You could tie the cathodes to ground and use an interstage gain control though.
Quote from: frequencycentral on April 06, 2009, 06:21:47 PM
The plates are not internally connected, but the cathodes are. You could tie the cathodes to ground and use an interstage gain control though.
Right, cathode. I'm not good with tubes yet. :icon_smile:
And the datasheet looks OK?
Quote from: CynicalMan on April 06, 2009, 09:18:59 PM
Quote from: frequencycentral on April 06, 2009, 06:21:47 PM
The plates are not internally connected, but the cathodes are. You could tie the cathodes to ground and use an interstage gain control though.
Right, cathode. I'm not good with tubes yet. :icon_smile:
And the datasheet looks OK?
Well its a medium mu twin triode, as is the 12au7, so worth a try. Jus't remember you can't use the regular Valvecaster gain control, it needs to be and interstage gain control.
http://www.pmillett.com/tubedata/HB-3/Receiving_Tubes_Part_2/6J6-A.PDF
Quote from: frequencycentral on March 28, 2009, 02:27:38 PM
I wonder if it would be possible to use a number of 1n4148 in series to drop the voltage........each one has a voltage drop of 0.7v if I recall. So four in series would drop 2.8 volts. Never tried it..........I wonder if it would work?
I've just been reading the 'Heaters' page over at Valve Wizard. Merlin says:
" A pair of ordinary high-current silicon diodes can be added to the heater chain to drop the heater voltage by about 0.7V. (If using a DC heater supply, only one diode will be needed.)"So I guess he means 1n400*, using four in series would drop 2.8v, using eight (seems a little excessive) would drop 5.4v.
There's also some really good info about series/parallel heaters and pairing mismatched heaters.
http://www.freewebs.com/valvewizard/heater.html
The Valve Wizard is great!
I've learned a lot from him, over the past month or so.
He was even kind enough to answer a couple of questions I asked him via Email.
glen
This is my first post here, on this site. I guess it is fitting that my first post be a request for help. I have just finished building this based on Dano's schematic and layout all the way back at the beginning of this thread. All I can manage to do is get a loud hum when I plug this into my amp. I have noticed that if I put my hands on the input/ output jacks and press down just slightly, I can hear a very static filled, quiet sounding strum of my guitar strings. I was hoping maybe that one of you that has been here would have an idea...Any good ideas / thoughts/ suggestions would be much appreciated. Thank you
Welcome aboard! :icon_wink:
Does the tube light up?! Have you checked the pins? Maybe you read them au contraire?! How is the thing powered? Tube is 12AU7?! Tell us more - pics appreciated too.
Let's make another Valvy work!!!
Quote from: glenn.b on April 19, 2009, 04:19:42 AM
This is my first post here, on this site. I guess it is fitting that my first post be a request for help. I have just finished building this based on Dano's schematic and layout all the way back at the beginning of this thread. All I can manage to do is get a loud hum when I plug this into my amp. I have noticed that if I put my hands on the input/ output jacks and press down just slightly, I can hear a very static filled, quiet sounding strum of my guitar strings. I was hoping maybe that one of you that has been here would have an idea...Any good ideas / thoughts/ suggestions would be much appreciated. Thank you
Posting your voltages at all 9 pins is an essential part of debugging. Here's mine, running at 12 volts, with the gain control set to maximum:
Pin 1: 3.02v
Pin 2: -0.518v
Pin 3: 0.00v
Pin 4: 0.00v
Pin 5: 11.97v
Pin 6: 8.21v
Pin 7: -1.285v
Pin 8: 0.00v
Pin 9: 5.91v
If you are running at 9 volts, all your voltages will be 25% less than mine.
Also worth reading this: http://www.diystompboxes.com/smfforum/index.php?topic=29816.0
Today I found this article on makezine ... I thought that somebody could be interested ...
http://www.electricwestern.com/diytubes.html
Thank both of you for the welcome!
Ok, this is pretty awful, but the values coming off my pins are way higher than yours, and I am only using a 9volt. As far as pics I have tried to capture it, but normally the pic overexposes , due to me trying to shoot it to close. My pins(sigh) are 1:9.24
2:8.51
3:000
4:9.33
5:9.34
6:9.34
7:8.93
8:000
9:9.33
Almost like there is a complete open. Anyway there it is-geez, I know I'm new to this!
And yes, tube is a 12au7.
Quote from: glenn.b on April 21, 2009, 04:10:57 PM
1:9.24
2:8.51
3:000
4:9.33
5:9.34
6:9.34
7:8.93
8:000
9:9.33
Check out your voltages and connections at pins 4, 5 and 9 first, that's the heater. Pin 9 should be half your supply, so about 4.5v. Pin 4 should be 0v and pin 5 should be 9v. Once you get the heater voltages sorted out we can look at the rest of you voltages, which will change once the heater is correct, so repost them. There should of course be no connection to pin 9, as it's the heater's centre tap and is unused in this circuit. Good luck, it will work eventually!
Thank you again for the push and the encouragement! When I get up tomorrow I will unsolder the whole works and then restart, working towards those numbers you gave me. I will let you know what I come up with just as soon as I get it together. gotta get the gremlin out...
i have a fender champ 600, a newer one, that i hack on. it sounds really nice with this tube-booster in front of it. thanks, guys, for making these things tangible.
goodluck debugging glen.b
Welcome to both of you - :icon_wink:
Man this thread keeps going and going...
Has anyone come up with simple mods to the valvecaster to make it function as a simple buffer. Maybe with just a little gain?
Quote from: dano12 on April 27, 2009, 10:13:40 AM
Man this thread keeps going and going...
Has anyone come up with simple mods to the valvecaster to make it function as a simple buffer. Maybe with just a little gain?
Yes it does Dano - it's been quite an inspiration. Though I think it's now offically too long to read!
Using just a single triode stage, a 100K plate resistor and a 100K cathode resistor, taking the output directly from the cathode through a cap value of your choice, will give you a non-inverting unity gain buffer.
Quote from: frequencycentral on April 27, 2009, 11:46:34 AM
Quote from: dano12 on April 27, 2009, 10:13:40 AM
Man this thread keeps going and going...
Has anyone come up with simple mods to the valvecaster to make it function as a simple buffer. Maybe with just a little gain?
Yes it does Dano - it's been quite an inspiration. Though I think it's now offically too long to read!
Using just a single triode stage, a 100K plate resistor and a 100K cathode resistor, taking the output directly from the cathode through a cap value of your choice, will give you a non-inverting unity gain buffer.
thanks buddy, I'll give that a try.
If I recall, setting it up like that will actually give you slightly less than unity gain, but like .99 or something, just a technicality, but I remember reading somewhere that that is why some people prefer to not use a cathodyne phase inverter.
Hello everyone!
I read almost all the replies in this thread and I built my valvecaster and then the twincaster; it's nice, but not really my favourite kind of sound.
Anyway, I still didn't get one thing: I tried to use an AD/DC transformer to power the circuit, and I get a quite loud constant hum, still I can hear the output of the pedal.
Why's that? Maybe a crappy transformer? If I use a 9V battery everything's fine, but I'd like to try to feed it with 12V.
The transformer has a trim that lets me choose the output voltage, and I tried 9V and 12V: the quite strange thing is that if I measure its output, I measure ~12.5V instead of 9V, and ~17V instead of 12V (if I recall correctly... I'm @ work right now :)). Can someone kindly shed some light on this? :)
Quote from: lazerphea on April 29, 2009, 11:30:56 AM
Hello everyone!
I read almost all the replies in this thread and I built my valvecaster and then the twincaster; it's nice, but not really my favourite kind of sound.
Anyway, I still didn't get one thing: I tried to use an AD/DC transformer to power the circuit, and I get a quite loud constant hum, still I can hear the output of the pedal.
Why's that? Maybe a crappy transformer? If I use a 9V battery everything's fine, but I'd like to try to feed it with 12V.
The transformer has a trim that lets me choose the output voltage, and I tried 9V and 12V: the quite strange thing is that if I measure its output, I measure ~12.5V instead of 9V, and ~17V instead of 12V (if I recall correctly... I'm @ work right now :)). Can someone kindly shed some light on this? :)
Sounds like your power supply is an unregulated one. What you need to do is get a 7812 voltage regulator and use that to regulate down the ~17v to a stable 12v. Also, add a 100uf electro cap across the power rails from +ve to ground. That wil get rid of your hum issues and give you a nice stable 12v. This method is mentioned elsewhere in this thread, a lot of people have used it.
The reason why you measured higher voltage on your transformer is 1) it is unregulated and 2) they design wallwarts to deliver a MINIMUM of 9V at the rated current, so if you are drawing less current, then the voltage will be higher.
Yes transformers can be real noisy sometimes.
My ValveCaster is housed in the same enclosure as a VooDoo lab OD, the valvecaster is powered by a transformer and is relatively quite.
The vooDoo is powered by a 9 volt battery.
The two circuits are totally separate from one and other, two channels in, two channels out of the enclsure.
Yet if I use the Voodoo while the valvecaster is powered up I get all kind of noise bleeding into the surrounding wires of the voodoo circuit.
I think I need to isolate the voodoo wires going to the pots away from the 120 volt wires that feed the transformer for the valvecaster!!
For now I just use one or the other.
(http://i107.photobucket.com/albums/m297/biggy-boy/amp2.jpg)
left side ValveCaser in, right side Voodoo in. The outputs are on the back.
I went to the reharsal yesterday, First time with this band, playing QUEENSRYCHE songs - me on the bass - I took my Valvy with me...Man, it's so good on bass...It just rounds up the sound to achieve the Eddie Jackson (bass god for me...) sound...
Just wanted to share this experience...
Quote from: Renegadrian on April 29, 2009, 04:09:27 PM
it's so good on bass...It just rounds up the sound to achieve the Eddie Jackson (bass god for me...) sound...
Just wanted to share this experience...
+1 about running a bass through it, sounds so good with a double musicman pickup.
Glen
frequencycentral, Ripthorn, thanks for the advices!
I bought today my 7812 and a small dissipator, and if I unterstood correctly what I have to do is:
- wire the transformer's output to the 7812's input
- take the output of the 7812 and feed the + pin of the electrolytic cap, while the - pin goes to ground
- take the +12V from the + pin of the cap
Right? :)
That is exactly right. Don't forget to ground the regulator, it uses that for a reference. Probably what I would do, though, is put an electrolytic cap before and another after the regulator, since the smoother the input voltage, the smoother the output voltage will be. An extra few cents is worth it.
If using 12.6v heater supply: pin 9 is not used, pin 4 and pin 5 are used. give one 12v+ and ground the other. @12v the heater draw is 150ma.
If using 6.3v heater supply: pin 4 and 5 are jumpered together and get 6v+ and pin 9 is grounded. @ 6v the heater draw is 300ma.
9v is not enough for a 12.6v heater. the current draw from the heater would kill a battery quick, so you ought to be using a transformer of some sort. might as well be 12v instead of 9v. better yet, get a 120-200v transformer and give a 12ax7 high plate voltage. everything becomes easy once you do this.
without a load, a power supply's voltage may be higher than the required 12.., like 15-17,, once you put the load across it ,, (the filament) it should drop to 12v (or just below). are you getting a 17v reading with the filament as a load? or without the tube installed, across pins 4 & 5?
Guys, I tried the 7812 ant it outputs a nice 11.40V supply, but now, instead of a constant hum I get a constant buzz! :D
Terminalgs, I don't get it... do I have to modify the tube's wiring? ???
Update: I rebuilt the valvecaster and the buzz disappeared, but... It has a crappy sound! :( No sustain and a farty distortion... ???
Ok, I'll try to debug it--- just a question: is it normal for the tube to be quite hot (sorry for the n00bish question)?
The tube will be hot to the touch, but it shouldn't be melting anything, etc. If it has a fartish sound, that sounds like a biasing problem. What current is your transformer rated at?
Quote from: lazerphea on April 30, 2009, 04:55:05 PM
Update: I rebuilt the valvecaster and the buzz disappeared, but... It has a crappy sound! :( No sustain and a farty distortion... ???
Ok, I'll try to debug it--- just a question: is it normal for the tube to be quite hot (sorry for the n00bish question)?
Post your voltages!
Sorry man, you're right! :)
Here are the voltages I measure at the tube's pins:
pin 1: 3.64
pin 2: 0.18
pin 3: 0.09
pin 4: 0.09
pin 5: 11.57
pin 6: 5.05
pin 7: -0.14
pin 8: 0.09
Quote from: lazerphea on April 30, 2009, 05:57:00 PM
Sorry man, you're right! :)
Here are the voltages I measure at the tube's pins:
pin 1: 3.64
pin 2: 0.18
pin 3: 0.09
pin 4: 0.09
pin 5: 11.57
pin 6: 5.05
pin 7: -0.14
pin 8: 0.09
They look pretty good, apart from pin 6, which is 3v less than it should be. Check the resistor value, and for shorts/bridges.
Quote from: frequencycentral on April 30, 2009, 06:02:25 PM
They look pretty good, apart from pin 6, which is 3v less than it should be. Check the resistor value, and for shorts/bridges.
Ok, I'm a total n00b... I switched R3 with R4! :(
Now everything's ok! I thank you a lot, frequencycentral!! :)
Tomorroy I'll try to rebuild the twincaster, and I'll post some news about it!
Thanks again man! :)
Quote from: lazerphea on April 30, 2009, 06:16:49 PM
Quote from: frequencycentral on April 30, 2009, 06:02:25 PM
They look pretty good, apart from pin 6, which is 3v less than it should be. Check the resistor value, and for shorts/bridges.
Ok, I'm a total n00b... I switched R3 with R4! :(
Now everything's ok! I thank you a lot, frequencycentral!! :)
Tomorroy I'll try to rebuild the twincaster, and I'll post some news about it!
Thanks again man! :)
Cool - up and running - that was a simple fix! Well done!
Quote from: frequencycentral on April 30, 2009, 06:02:25 PM
Cool - up and running - that was a simple fix! Well done!
Thanks thanks thanks! :)
No Mine only gets slightly warm to the touch.
Glen
I should confess that i have never actually built the valvecaster, but I am doing some other tube projects.
I just finished mine last night, and it sounds great!!! Full warm tone. A little hiss way way in the back, but I'll get to that. (any ideas what it could be?) I built mine in a BB, so I have the option for a twin. I like the look of a glowing tube, so I put a orange LED in the middle whole in the socket (i just jammed a 3mm in there). Looks amateurish, since I lost my socket screwes, but it works! I also keep the voltage to the tube on constantly, I just bypass the signal. Don't know it this is a good idea, but I guess off-ing and on-ing the DC to the tube isn't best for the tube...
(http://i651.photobucket.com/albums/uu237/kristoffereide/DSC00780.jpg)
Looks good!
I like the glow.
Ya It ok to leave the heaters going while it is in standby or bypassed, that way it is ready to go when you stomp on the switch.
Glen
Nice build
Almost all pedals are setup so the circuit is always drawing current, no matter if your signsal is going trhough or not.
If you cut the voltage everytime you hit the switch you'd have heater issues. You'd have to hit the switch and wait while the heaters "ramp up" and start emitting electronics before you got sound.
yes, you are right. When I think about it, all pedals only bypass the signal...
Quote from: kristoffereide on May 01, 2009, 04:35:30 AM
Looks amateurish, since I lost my socket screwes, but it works! I also keep the voltage to the tube on constantly, I just bypass the signal. Don't know it this is a good idea, but I guess off-ing and on-ing the DC to the tube isn't best for the tube...
The black screws look good to me, matches the black knobs!
Yes, as Kurtlives said keep the tube powered and just bypass the signal. The tube changes tonal characteristics (at least mine does) as it warms up. I personally like my Valvy's tone when it's still cold, has a more gritty tone. After it warms up (20 minutes) the tone becomes a smoother overdrive.
Quote from: Ripthorn on April 30, 2009, 08:26:59 PM
I should confess that i have never actually built the valvecaster,
Isn't there some law against that around these parts?
I'm waiting for my account to be deactivated as we speak... I have a few 12au7's, but no sockets and my submini project is taking a lot of free time (but almost done).
Quote from: Ripthorn on May 01, 2009, 02:37:28 PM
I'm waiting for my account to be deactivated as we speak... I have a few 12au7's, but no sockets and my submini project is taking a lot of free time (but almost done).
I've reported your confession to the moderator. Pleading 'no sockets' is no defence. This kind of behavior really shouldn't be condoned or tolerated.
.........and what the hell is a 'submini tube' ???
All this talk about submini tubes, could give a guy a inferiority size complex.
No honest, it's normally bigger like a ValveCaster.......
Quote from Mrs Biggy Boy: 'Oooh Glen - yours is the BIGGEST Valvecaster I've ever seen!'
Quote from: frequencycentral on May 01, 2009, 05:31:20 PM
Quote from Mrs Biggy Boy: 'Oooh Glen - yours is the BIGGEST Valvecaster I've ever seen!'
LOL
Ya but she was only saying that, to distract me while she took money out of my walet to go shopping. :-\
LOL - you guys make me laugh! :icon_lol:
Is there any news on the infamous Promiscuous Girlfriend yet?
Hello! This is my first time posting here.
This thing sounds fantastic on guitar! My question is whether anyone has tried it on bass? Anyone have some sound clips of it on bass? I'm wanting to build an overdrive but I really don't like the jagged sounding nature of transistors for overdrive. You guys say that the stock Valvecaster is somewhat bassy sounding but would it need some larger value caps to let a bit more bass through anyway? I'm also guessing the tone stack would need a different cap to bring the response range down a bit.
Sorry for so many questions. I'm fairly new at pedal making and I've NEVER worked with tubes before.
Look on the previous page, Adriano and someone else were talking about how good this sounds with a bass. You could try it stock first and see if you like it. If not, you can change in/out caps and tonestack values to get what you want. You can use Duncan's tone stack calculator to make sure you get the right tone stack range.
Quote from: bassmannate on May 07, 2009, 09:42:13 AM
My question is whether anyone has tried it on bass?
Hi bassmanate welcome to the forum.
Yes it does sound good when used with a bass.
Especially if it is a lefthanded bass :icon_lol:
I have no sound clips to offer at this time though.
I roll back the gain to clean up the sound.
Glen
Quote from: kristoffereide on May 01, 2009, 04:35:30 AM
I just finished mine last night, and it sounds great!!! Full warm tone. A little hiss way way in the back, but I'll get to that. (any ideas what it could be?) I built mine in a BB, so I have the option for a twin. I like the look of a glowing tube, so I put a orange LED in the middle whole in the socket (i just jammed a 3mm in there). Looks amateurish, since I lost my socket screwes, but it works! I also keep the voltage to the tube on constantly, I just bypass the signal. Don't know it this is a good idea, but I guess off-ing and on-ing the DC to the tube isn't best for the tube...
(http://i651.photobucket.com/albums/uu237/kristoffereide/DSC00780.jpg)
Nice going, I only think putting that tube beside the stomp switch is creepy.
In the heat of playing, and suddenly wanting to stomp valvy, I would certainly kick that tube out of commission fast.
Personally I would have put the tube above the pots to give the footswitch a little more space.
In this case you might consider putting around the tube some sort of cage, which also would provide extra protection when carrying it around..
(Ore you just want it lying on the same spot all the time, always engaged, in that case,, never mind. :icon_wink: )
It surely helps to be lefthanded! :icon_razz:
Well, I play both guitar and bass and I really enjoy my Valvy. I use the toneless version, and use the amp EQ for small adjustments, but it works just fine for my ears, I just plug and play! As the other southpaw wrote, you can get nice "fat" tone with the gain rolled down a little, to get a full but undistorted sound.
I got a good sound to play in a queensryche cover band (second reharsal for now...)
Wanna know the way it works with bass?! I uploaded a couple of samples I did some time ago.
hope that helps.
http://www.aronnelson.com/gallery/main.php/v/Renegadrian/bass-a.mp3.html
http://www.aronnelson.com/gallery/main.php/v/Renegadrian/bass-b.mp3.html
Very nice. Sounds like it will be capable of producing more than enough overdrive for me. Of course, I have a little dilemma now. My next project WAS slated to be an Orange Squeezer but after hearing this, I'm not sure which I want to do first. I really NEED a compressor for my rig but I really WANT a Valvecaster. Decisions, decisions... :icon_mrgreen:
I built both - I definitely say GO VALVY!!!
Does the Valvy really provide that much compression to the signal? I don't have much experience with tubes (heck, all the bass amps I've ever owned have been good ole' reliable Hartke combos!) so I don't have much insight into how they alter the sound.
I think I can say it acts like a compressor in its way...The sound on the bass is actually tight and round, very full...It boosts the signal in the best way! And I love to keep it as a booster with the gain at mid run or just add some grit turning it up...
Ok, I think you just about have me convinced.
Hmmm...I saw MUCH earlier in the thread someone mention using a 12au7 in place of the 4558 in the Orange Squeezer...Perhaps this could be reversed and a switchable feedback compressor could be integrated into the Valvy...I'll have to think about this for a bit...
Alright, I think I've decided that I'm going to build the Valvecaster. I just have a few questions for you guys.
First, what brand tubes are you guys using? I don't want to go bottom of the barrel but I don't really want to spend more than $10-$15 on a tube.
Second, what all do I need to mount the tube? Obviously I need a socket. Will any 8 pin tube socket do? Looks like there's quite a selection at tubedepot.com. Is there anything else I need to secure the tube like a base or retainer since the tube will be sticking quite proudly out of the enclosure? Like I said before, I've never even owned anything with tubes in it much less built anything with tubes.
Doh. That's right. I'm confusing myself because we're only USING 8 pins on the tube. So, any of the 9 pin sockets will work?
Quote from: bassmannate on May 08, 2009, 10:41:58 AM
Alright, I think I've decided that I'm going to build the Valvecaster. I just have a few questions for you guys.
First, what brand tubes are you guys using? I don't want to go bottom of the barrel but I don't really want to spend more than $10-$15 on a tube.
Second, what all do I need to mount the tube? Obviously I need a socket. Will any 8 pin tube socket do? Looks like there's quite a selection at tubedepot.com. Is there anything else I need to secure the tube like a base or retainer since the tube will be sticking quite proudly out of the enclosure? Like I said before, I've never even owned anything with tubes in it much less built anything with tubes.
There is no specific brand to use...You can buy a new tube (EH are about 7 euros) or go shopping thru EvilBay, you can get some vintage tubes for even less (I usually paid no more than 4 euros each)
You also need a 9pin socket, with or without its shield.
Have a look HERE (http://www.banzaieffects.com/Tube-Retainers-Clips-and-Shields-c-444.html) and HERE (http://www.banzaieffects.com/9-pin-Noval-Sockets-c-442.html)
The tube will be firmly secured by its pins in the socket.
Awsome. Ordered some parts today. I'm going to make the gain switchable with a second footswitch. That way, I can use it as a boost unless I want a bit more overdrive. I'm going to put a 50k resistor in along with the 50k pot and switch back and forth with a dpdt footswitch. I even got a bi-color led that will change color depending on what's on.
well after about a month of being broke and having to put this project off, i finally ordered some tube sockets the other day and i am hoping to see them in the mail today (not likely but who knows) i just wanted to know how well is the wiring layout on page 1 drawn? any revisions i need to note before putting things together? i cant wait to start building this one! i will post a picture of my finished project when i can get it to work. man, cant wait!
alright so i am about halfway through and thoroughly drunk :icon_biggrin:
i have decided to postpone the completion until tomorrow. i will take pictures of the finished project (i will try to add some circuit shots, however ugly they are) and gives some a little backstory as too how i got it done. see you all tomorrow, hopefully i will have an awesome pedal!
Yeah, I can't imagine that soldering irons and alcohol mix too well.
Quote from: bassmannate on May 12, 2009, 09:53:23 AM
Yeah, I can't imagine that soldering irons and alcohol mix too well.
They don't. Not at all. Ha ha ha.
Well, I ordered my parts yesterday. Unfortunately, the socket I wanted was backordered so I may be a week or two back on building this thing.
Quote from: panterica on May 12, 2009, 10:01:44 AM
Quote from: bassmannate on May 12, 2009, 09:53:23 AM
Yeah, I can't imagine that soldering irons and alcohol mix too well.
They don't. Not at all. Ha ha ha.
yes of course i didnt get much done last night, woke up this morning and finished, and of course it doesnt work :icon_frown:
so now im in the debugging phase, can anyone here help? pretty much i get nothing at all when i plug everything in. waited a few minutes for things to heat up and still didnt work. i get nothing from the tube (no heat/light at all) and no sound. i followed the wiring layout and dont know where i went wrong, it might be where an electrolytic capacitor (the 1uf) went. does the neg side go to the pot or the tube? cuz i have it going to the pot (thats what i gathered from the schem).
so yes, help would be greatly appreciated before i just ram this thing down the garbage disposal ;D
thanks!
mike
Quote from: KorovaMilkBar on May 12, 2009, 04:15:40 PM
it might be where an electrolytic capacitor (the 1uf) went. does the neg side go to the pot or the tube? cuz i have it going to the pot (thats what i gathered from the schem).
You've got the cap correct. What about your tube pinout itself? Looking at the tube upside down, ie looking at the pins, they go clockwise 1 to 9. Also, posting your voltages will be essential for a debug. Don't give up on it - it will work! And the thrill you'll get when it does work is better than cocaine........
the pinout is numbered right on the socket itself (which i though was pretty badass myself, thanks korea!)
fa sho i will get some voltage readouts when i get a chance, should i do just pins 1-9? anything else you need?
im gonna wait till later on to clear my head before i try to do anything with
also, what is the polarity of this? or does it go both ways
(bill gates : haha he said "they go both ways"!
ted turner : like a bisexual!
michael eisner : thank you ted, that was the joke :icon_rolleyes: )
Quote from: KorovaMilkBar on May 12, 2009, 04:32:37 PM
fa sho i will get some voltage readouts when i get a chance, should i do just pins 1-9? anything else you need?
Yeah, just 1 through 9.
And state your power supply voltage and amperage, and if it's a regulated supply or not.
And check all your resistor values at least twice.
Quote from: KorovaMilkBar on May 12, 2009, 04:32:37 PM
also, what is the polarity of this? or does it go both ways
Do you mean the power polarity? It's negative ground.
Hi guys,
My name is Dan, and this is my first post. I've been a guitar addict for the past 24 years... I've been reading this thread for the past month and I just finished it yesterday. Great work guys! Anyway, I had pretty specific plans to build a tube overdrive pedal when I found this thread so I found that I had to tweak the circuit quite a lot and in the end, it looks quite different but greatly inspired by the valvecaster non-pcb layout. My first attempt (about 3 weeks ago) was to squeeze a 386-based boost and the valvecaster into a hammond 1590 style box. Success! But I nicknamed that pedal the "firehazard" pedal for obvious reasons. My friend has been borrowing it for the past two weeks and I'm happy to say his house hasn't burnt down. On that first pedal I experimented with mainly the input and output caps. I tended to filter out the bass quite a lot by using a 0.0022 mF cap on the input. I don't remember the rest of the details. Here's are a couple photos:
(http://homepage.mac.com/dshimmyo/musicForBlog/hybridValvecaster.jpg)
(http://homepage.mac.com/dshimmyo/musicForBlog/hybridValvecasterInside.jpg)
I chose to build that pedal on a patterned circuit board from radioshack. That wasn't much fun, I find those tiny boards too cramped to work on. Whenever I tweaked one part another connection would break.
That pedal sounded pretty good but I wanted more overdrive so I started on the twin valve circuit. I spent the past 2 weeks trying different plate resistors, cathode resistors, cathode bypass caps etc. to try to get the perfect tube overdrive sound. I thought I was pretty close so I built it. This is what I built over the past 2 nights:
(http://homepage.mac.com/dshimmyo/musicForBlog/twinvalveFront.jpg)
(http://homepage.mac.com/dshimmyo/musicForBlog/twinValveInside.jpg)
I'm much happier with the pcb-less layout, it looks pretty cool. I love the cleaner look of this circuit. I still need to install LEDs and tack the voltage regulator onto the chassis. I'm very happy with the sounds I'm getting out of this circuit although I think I set the gain too high on the first 2 stages, causing the overdrive to sound a bit loose to my ears.
Anyway, I'll be working on this circuit because my intention is to perfect it and have my own personal ultimate overdrive on my pedalboard. At some point I'll post all of the specs and post some sound samples. You guys have taught me so much, this forum is amazing. I need to get some software to draw up some sweet schematics.
I better get back to work.
Cheers,
Dan
Hello Dan, (http://i149.photobucket.com/albums/s41/ILive4ChristAndGod/Greetings/Welcome/029.gif) THX for your report and your pics!!!
Welcome Dan
Nice Job (http://i107.photobucket.com/albums/m297/biggy-boy/rockon2.gif)
Both of the pedals look great!
Glen
hahah, ok, i DO have my pedal working now (technically) but now
1. tube is heating slightly but not lighting up that i can tell. it is supposed to glow slightly right?
2. their is a very loud low end hum (about as loud as the guitar)
3. the distortion isnt as much distortion as it is some sort of weird ring modlike effect. buzzy (slightly buzzy) and weird is the best way to describe it.
i checked my power supply with a multimeter and it read at bout 17 (ouch!) when it was supposed to be 9 volts. switching it to 6 volts brings it to a very nice 9.05-10.
i will get the pin readouts sometime later, but definitely tonight.
thanks
mike
Quote from: KorovaMilkBar on May 12, 2009, 07:53:43 PM
i checked my power supply with a multimeter and it read at bout 17 (ouch!) when it was supposed to be 9 volts. switching it to 6 volts brings it to a very nice 9.05-10.
That's an unfiltered (it hums) unregulated (it lies about it's output) power supply. Get yourself a 7812 voltage regulator and a 100uf electro cap and regulate/filter that sucker! Run you Valvecaster at 12 volts - better than 9 volts. Sounds like you have issues around the heater if there is no glow.
Quote from: KorovaMilkBar on May 12, 2009, 07:53:43 PM
the distortion isnt as much distortion as it is some sort of weird ring modlike effect. buzzy (slightly buzzy) and weird is the best way to describe it.
You invented a new effects pedal! Cool - soundclips? Schematic? :icon_biggrin:
yes i would beleive it is an unfiltered unregulated power supply, i forgot to say it was a "deluxe universal ac/dc adaptor" (made in china) and it has 6 different tips.
where would i obtain this regulator? is it an outside thing (its own housing?) or another component?
also, here are the readouts i got
pin 1 : 5.67 v
pin 2 : 0
pin 3 : 0
pin 4 : 0
pin 5 : 7.22
pin 6 : 6.30
pin 7 : 0
pin 8 : 0
pin 9 : 3.63
thanks for the help guys!
Quote from: KorovaMilkBar on May 12, 2009, 08:19:10 PM
yes i would beleive it is an unfiltered unregulated power supply, i forgot to say it was a "deluxe universal ac/dc adaptor" (made in china) and it has 6 different tips.
where would i obtain this regulator? is it an outside thing (its own housing?) or another component?
also, here are the readouts i got
pin 1 : 5.67 v
pin 2 : 0
pin 3 : 0
pin 4 : 0
pin 5 : 7.22
pin 6 : 6.30
pin 7 : 0
pin 8 : 0
pin 9 : 3.63
thanks for the help guys!
Here's mine, verified and working:
Pin 1: 3.02v
Pin 2: -0.518v
Pin 3: 0.00v
Pin 4: 0.00v
Pin 5: 11.97v
Pin 6: 8.21v
Pin 7: -1.285v
Pin 8: 0.00v
Pin 9: 5.91v
Looks like you supply is only 7.22v. that won't power the heater, so eveything else will be off too. 7812 look like a slightly bigger transistor. Browse back through this thread for how to use it. Or do a search.
Hi guys,
So, I've been trying to incorporate my twin valve pedal into my pedalboard and I ran into a little issue. The valvy hates having buffered pedals in front of it but sounds fine going into them. Is there some way I can get it to play nice with and without buffered pedals? Is it just a matter of tweaking the grid leak resistor or something? It's important that I get it to work under both situations because in my pedalboard I built a pedal that changes the order of the pedals. Any ideas why the valvy doesn't play nice?
-Dan
Hi all!
I'm still stuck with this build... the problem is: I built the Valvecaster with a 7812 in front of my power supply, and everything is ok, no hum, nice sound.
So I tried to build the Twincaster, and I get a loud hum, as loud as the output of the circuit. Using a 9V battery ends the hum.
The strange thing is: if I leave on my breadboard just the Valvecaster and wire the second tube only to ground and to V+ (pins 4,5,8), no other wirings to the circuit, I get the loud hum... why's that?? :(
Hey guys,
What I thought was a problem with my buffered pedals turned out to be wonky patch cables. I believe the cable I used has too much capacitance and the new pedal is uber-sensitive to it. I need to build a cable tester or something.
lazerphea: When I was testing my circuit, I was able to get clean sounds off of battery and the ecb006 adapter (dunlop 18vdc). Then I bought a 12vdc power supply from radioshack and all I got was hum. Since your circuit sounds good with a battery I'd blame it on your power supply.
-Dan
What is your power supply rated to? You can get massive hum if there isn't enough current going to the tubes (heaters). Check to make sure your power supply and regulator can handle what you are asking.
I get 11.60V out of my power supply passing through the 7812 voltage regulator... dunno if it's enough... ???
Maybe I should try another adapter, as shimster suggested...
Quote from: KorovaMilkBar on May 12, 2009, 07:53:43 PM
1. tube is heating slightly but not lighting up that i can tell. it is supposed to glow slightly right?
not enough power getting to the tube?
lazerphea: It is also important to make sure you get enough current. I believe it's around 150mA for each tube. That radioshack power supply that generated tons of noise was rated at 500mA but still generated so much noise. I never figured out why it was noisy though...
By the way guys, I've been hearing really great tones out of my twin valve circuit. I can't wait to post sounds and schematics for y'all to try! Too bad I have a day job taking up all my time!
Quote from: lazerphea on May 13, 2009, 09:42:06 AM
I get 11.60V out of my power supply passing through the 7812 voltage regulator... dunno if it's enough... ???
Maybe I should try another adapter, as shimster suggested...
Is that with load? Power supply voltages will change a good bit with and without load, especially if what is feeding your 7812 doesn't have the juice the tubes are asking for.
For all the new menbers having trouble with the power supply, I made this...Hope it helps!
(http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=39755&g2_serialNumber=1)
Very nice! Thanks!
Keep in mind that if you want to get proper voltage regulation with a 7812 regulator you have to feed in at least 14.5 volts. The input has to be at least 2.5 volts higher than the output.
Quote from: Renegadrian on May 13, 2009, 06:35:20 PM
For all the new menbers having trouble with the power supply, I made this...Hope it helps!
(http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=39755&g2_serialNumber=1)
Thanks man, but I already use a 100uf cap at the input and another 100uf cap at the output of the 7812... I think I really need a better adapter :)
No, the one's you're thinking of are audio coupling capacitors. This one is not in the signal chain. It's across the +9v and the ground to help filter any noise coming in on the power adapter.
Quote...I already use a 100uf cap at the input and another 100uf cap at the output of the 7812...
I believe he said the right thing, he has 2 caps and not only one placed at the 7812. So no signal chain involved, reading what he wrote...
Quote from: Renegadrian on May 14, 2009, 06:07:58 PM
Quote...I already use a 100uf cap at the input and another 100uf cap at the output of the 7812...
I believe he said the right thing, he has 2 caps and not only one placed at the 7812. So no signal chain involved, reading what he wrote...
I also use a cap before and after the voltage regulator, but I'll put a resistor inline before the first cap to make an RC filter
-----/\/\/\-------|---------------REGULATOR--------|------------
_|_ _|_
___ ___
| |
Quote from: Renegadrian on May 14, 2009, 06:07:58 PM
Quote...I already use a 100uf cap at the input and another 100uf cap at the output of the 7812...
I believe he said the right thing, he has 2 caps and not only one placed at the 7812. So no signal chain involved, reading what he wrote...
Ah, so he did. All I read was the input and output. Didn't read the 7812 part.
Quote from: Renegadrian on May 13, 2009, 06:35:20 PM
For all the new menbers having trouble with the power supply, I made this...Hope it helps!
(http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=39755&g2_serialNumber=1)
haha, man your cool renegadrien! i was pretty sure i knew how to put that all together but the diagram always helps me about a billion times. thanks!
8) <----you
Yeah, I am glad my drawing is helpful to someone!!!
Quote from: Renegadrian on May 14, 2009, 06:07:58 PM
Quote...I already use a 100uf cap at the input and another 100uf cap at the output of the 7812...
I believe he said the right thing, he has 2 caps and not only one placed at the 7812. So no signal chain involved, reading what he wrote...
Exactly! Ripthorn suggested me to do so :)
Quote from: Ripthorn on May 13, 2009, 01:18:36 PM
Quote from: lazerphea on May 13, 2009, 09:42:06 AM
I get 11.60V out of my power supply passing through the 7812 voltage regulator... dunno if it's enough... ???
Maybe I should try another adapter, as shimster suggested...
Is that with load? Power supply voltages will change a good bit with and without load, especially if what is feeding your 7812 doesn't have the juice the tubes are asking for.
Ehm, sorry... what do you mean by "load" ???
Oh, and maybe could help to know that the tubes don't light up at all...
What I was asking is if the 11.6V was when the tubes were drawing their current that they need. If the tubes don't light up, that indicates that the heaters aren't getting either enough voltage or enough current. If your 7812 doesn't have a heatsink, it is possible that it can't dissipate enough power to continue delivering the current you are asking of it. Just to clarify, is the 11.6V coming out of the 7812? What are the specs of the power supply that is feeding the 7812?
alright, so i have my pedal pretty much working nicely aside from the brutally loud hum. i checked my voltage at pin 6 again (with load) and its running at a slightly hot 13.6 volts. is this not good? will it greatly reduce the life of the tube? also, will the voltage regulator fix this along with the hum? you know, i would think a voltage regulator would like, you know, regulate voltage, im just wanna know if its gonna do something like bake cookies instead.
I'm sure this has been addressed before, but I find that my both my Valvecaster and Subcaster are just too bassy. Would a simple input/output cap change take care of that?
Quote from: svstee on May 15, 2009, 09:04:40 PM
I'm sure this has been addressed before, but I find that my both my Valvecaster and Subcaster are just too bassy. Would a simple input/output cap change take care of that?
Yes
I changed the cap between the first and second stage to a smaller value. Check back a bunch of pages it was discused there.
I did it from the start, so I don't have any way of comparing it to the original value of cap.
Edit:
heres the page.
http://www.diystompboxes.com/smfforum/index.php?topic=63479.1100
I finally recorded a little clip of my latest pedal, the twin valve circuit that I've been working on for the past 3 weeks. I'm playing a gibson sg special through a cornford harlequin amp. Let me start by saying I'm super picky about my guitar sounds, and I'm disappointed in the sound of this recording. I think the close micing technique and low amp volume takes away from the brilliance of this pedal. I'm saying that now having just come back from a jam session with some friends. I had this pedal plugged into a mesa boogie dual rectifier and it sounded really sweet. With this circuit I think I went too far into the "brown sound" territory for my taste. Future pedals will likely be based on a cleaner tube circuit with a jfet boost to achieve overdrive. Well, enough talk, here's the sample:
http://homepage.mac.com/dshimmyo/musicForBlog/blinky01Test.mp3
Sounds good Dan. I like it. (http://i107.photobucket.com/albums/m297/biggy-boy/rockon2.gif)
Nice guitar playing too.
WOW! Sounds great! You really nailed down that Punchy, Crunchy distortion! Sounds like a very versatile tone.
If it sound good thru that Harlequin I can imagine how it sounds thru your Mesa! :icon_eek:
Great licks too!
Ok, I had some time to make some experimentations, and here's what I've found:
- Just out of the adapter I read a voltage of 17.19V
- the output of the 7812 reads 11.01V
- if I add the 100uf caps to its input and output the voltage raises to 11.60V
- the same voltage is present an the pin N. 5 of the 12au7, when I connect the power to the circuit.
I get a very sloppy and uncomfortable sound out of it and the situation gets worse and worse as I play through the circuit; here's a soundclip of what I get after about 15 minutes of playing:
http://www.paoloscala.net/diy/12v.mp3 (http://www.paoloscala.net/diy/12v.mp3)
The sound degradates a lot...
So I tried to feed the tube with the 17.19V original voltage, and here's what I get:
http://www.paoloscala.net/diy/17v.mp3 (http://www.paoloscala.net/diy/17v.mp3)
Ignoring the hum, which I understood is given by the unfiltered adapter, the sound is still crappy and with no sustain at all... additionally, the tube doesn't lit up that much: I can see two filaments getting incandescent but that's it.
Maybe I should get a better tube (it's an Electro Harmonix)?
Thanks all.
EDIT: I forgot the adapter specs:
- it's a variable voltage adapter that spans from 1.5V to 12V, and I read: 500mA6VA(max) ??? :)
Ciao Paolo...
* Pins 4 and 5 of the 12**7 family are the heaters, one gets V+ and the other is tied to ground. So it's normal to have the same voltage from the power jack up into the heater (pin 5), that's how it's meant to be! :icon_biggrin:
* Regarding the light emission, the tube is not a light bulb!!! However each tube is different...I have a EH in my Valvy #001, and you barely can see the 2 filaments working - other tube do light up more, but that doesn't necessarely mean they are better...
* Regarding the wall wart - as you can read on the net, the heater current needed is 300mA, and you should add some more for the rest of the circuit - I believe it shouldn't be more than 400mA total. I run mine with a 500mA or a 1A, but never heard big differences, so yeah 500mA is good enough.
* I believe the problem you got could be related on the components/wiring on the signal part, and not a problem on the power part of the assembly.
Maybe you should try another wall wart, so we can be sure if that's to blame, or just go mad and start it over.
Quote from: Renegadrian on May 17, 2009, 05:28:08 PM
Ciao Paolo...
* Pins 4 and 5 of the 12**7 family are the heaters, one gets V+ and the other is tied to ground. So it's normal to have the same voltage from the power jack up into the heater (pin 5), that's how it's meant to be! :icon_biggrin:
Ciao Adriano! Yeah, I know but I specified that to make sure everything's fine with the circuit's alimentation :)
Quote
* Regarding the light emission, the tube is not a light bulb!!! However each tube is different...I have a EH in my Valvy #001, and you barely can see the 2 filaments working - other tube do light up more, but that doesn't necessarely mean they are better...
Ok! :)
Quote
* Regarding the wall wart - as you can read on the net, the heater current needed is 300mA, and you should add some more for the rest of the circuit - I believe it shouldn't be more than 400mA total. I run mine with a 500mA or a 1A, but never heard big differences, so yeah 500mA is good enough.
* I believe the problem you got could be related on the components/wiring on the signal part, and not a problem on the power part of the assembly.
Maybe you should try another wall wart, so we can be sure if that's to blame, or just go mad and start it over.
Good, I'll try to rewire it and get another wall wart asap!
Thanks for the support, man!
When working with tubes and the sound degrades over time, that still makes me think that it is a power issue, because that is almost identical to a problem I had when working with the submini amp I am building. It played fine, but then started dying out. That was because the regulator got so hot it could no longer dissipate the power needed to keep the voltage regulated.
First, your adapter is designed to deliver about 12V when run at max load (all 500mA) and a 7812 needs at least 14V on it, so if you are drawing 400mA, chances are your 17V is going to drop to maybe 13 or so, which won't be enough for the 7812. If it does still provide 14V, then the 7812 probably isn't able to handle the power dissipation for too long, so you would need a heatsink there.
Second, it is entirely possible that it is a combination of something with the signal path and power supply. Perhaps you accidentally put in a wrong value (10k instead of 100k or something like that)? Also, how are you getting the 6V for the heater (or is this the twin tube version?). If you don't have quite enough voltage to run a 7812 or similar, you can always get a zener diode and wire the anode to ground and the cathode to both the +V part of your circuit and the voltage in. This will shunt anything over 12V, even if it is 12.5V. Good luck.
pull the tube from the socket. measure VDC across pins 4 and 5. if you have 12V or more (and your power supply is at minimum 150ma + whatever the rest of your circuit will draw), you have enough filament voltage.
if it sounds bad try a different tube. are you using the 12ax7 ? or 12AT7 or 12AU7 ?? in starved plate circuits, 12ax7s don't seem to sounds as good at the other tubes in that family with lower amplification factors. Thats been my experience, and it has been echoed in various forums for several starved plate circuits. with my B.K.Butler TubeDriver, I didn't get an overdrive sound that I liked until I dropped the 12AX7 to a 12AT7. oddly enough, the 12AT7 is typically thought of as not a good tone-shaping tube for early gain stages (compared to the 12AX7 and 12AY7), and it is often used a Phase inverter tubes.
your sound clips sound similar to the sounds I was able to get out of some of the starved plate circuits I played with (one with 12VDC, one with 40VDC,,, and another with 28VDC ( http://www.guitarship.org/stp.html ). it was disappointing to discover that I'd have to use SS op amps to get enough gain to feed the tubes (like a BK Butler, Guyatone, or Tonebone..), so I moved to High Voltage tube pedal circuits and its been a lot of fun. -- not that there anything wrong with SS circuits, but if I'm going to build a SS pedal, there are other circuits I think I'd rather do...
Paolo,
I just want to mention that the sounds you're getting don't sound anything like the bad power supply that I got from radioshack. It does make me think you have a grid leak resistor that is too small or possibly a short somewhere in your circuit. Sort of a wild guess, but if you're going to rewire it anyway, you might have already fixed it. Good luck!
-Dan
Quote from: Ripthorn on May 18, 2009, 09:55:27 AM
When working with tubes and the sound degrades over time, that still makes me think that it is a power issue, because that is almost identical to a problem I had when working with the submini amp I am building. It played fine, but then started dying out. That was because the regulator got so hot it could no longer dissipate the power needed to keep the voltage regulated.
First, your adapter is designed to deliver about 12V when run at max load (all 500mA) and a 7812 needs at least 14V on it, so if you are drawing 400mA, chances are your 17V is going to drop to maybe 13 or so, which won't be enough for the 7812. If it does still provide 14V, then the 7812 probably isn't able to handle the power dissipation for too long, so you would need a heatsink there.
I forgot to point out I have an heatsink mounted over the 7812.. :icon_redface:
Quote
Second, it is entirely possible that it is a combination of something with the signal path and power supply. Perhaps you accidentally put in a wrong value (10k instead of 100k or something like that)? Also, how are you getting the 6V for the heater (or is this the twin tube version?). If you don't have quite enough voltage to run a 7812 or similar, you can always get a zener diode and wire the anode to ground and the cathode to both the +V part of your circuit and the voltage in. This will shunt anything over 12V, even if it is 12.5V. Good luck.
I checked everything again and I found some errors in the wiring... :icon_redface: :icon_redface:
The sound seems to not degradate over time, but I couldn't play more than 10 minutes or so, and I didn't noticed any sound degradation... still the distortion is unpleasant, especially if I play low frequency notes (E and A strings).
Quote from: terminalgs on May 18, 2009, 02:12:33 PM
pull the tube from the socket. measure VDC across pins 4 and 5. if you have 12V or more (and your power supply is at minimum 150ma + whatever the rest of your circuit will draw), you have enough filament voltage.
I measure 11.60V... is it bad, right?? ???
Quote
if it sounds bad try a different tube. are you using the 12ax7 ? or 12AT7 or 12AU7 ?? in starved plate circuits, 12ax7s don't seem to sounds as good at the other tubes in that family with lower amplification factors. Thats been my experience, and it has been echoed in various forums for several starved plate circuits. with my B.K.Butler TubeDriver, I didn't get an overdrive sound that I liked until I dropped the 12AX7 to a 12AT7. oddly enough, the 12AT7 is typically thought of as not a good tone-shaping tube for early gain stages (compared to the 12AX7 and 12AY7), and it is often used a Phase inverter tubes.
I use a 12AU7.
Quote from: shimster on May 18, 2009, 04:07:29 PM
Paolo,
I just want to mention that the sounds you're getting don't sound anything like the bad power supply that I got from radioshack. It does make me think you have a grid leak resistor that is too small or possibly a short somewhere in your circuit. Sort of a wild guess, but if you're going to rewire it anyway, you might have already fixed it. Good luck!
-Dan
No way man! Maybe I'm doomed to not to get this beast working, maybe the karma is telling me to go solid state instead! :D :D
Paolo! Don't give up just yet! Can you post a sample of the current sounds? I found the distortion of the original valvecaster to be too dark and muddy so I tweaked the snot out of the circuit until it sounded good! What kind of sound are you going for?
quote author=terminalgs
pull the tube from the socket. measure VDC across pins 4 and 5. if you have 12V or more (and your power supply is at minimum 150ma + whatever the rest of your circuit will draw), you have enough filament voltage.
my bad, I wrote that the heaters wanted 300mA, while they want only 150mA when running at 12V - I believe the rest of the circuit needs no more than 50 mA?! but I may be wrong on that...Anyway you surely won't go over the 500 mA limit...
12ax7s don't seem to sounds as good at the other tubes in that family with lower amplification factors. Thats been my experience, and it has been echoed in various forums for several starved plate circuits. with my B.K.Butler TubeDriver, I didn't get an overdrive sound that I liked until I dropped the 12AX7 to a 12AT7. oddly enough, the 12AT7 is typically thought of as not a good tone-shaping tube for early gain stages (compared to the 12AX7 and 12AY7), and it is often used a Phase inverter tubes.
Yeah, Me too, tried to experiment with the AX but no success...While I just LOVE the AT!!!I made my own layout for a heavy distortion!!!
it was disappointing to discover that I'd have to use SS op amps to get enough gain to feed the tubes (like a BK Butler, Guyatone, or Tonebone..), so I moved to High Voltage tube pedal circuits and its been a lot of fun. -- not that there anything wrong with SS circuits, but if I'm going to build a SS pedal, there are other circuits I think I'd rather do...
Absolutely agree with you on that, I really don't like those "hybrid" circuits...I'd rather go all tube or no tube at all...
Hey, I'm a complete noob at building pedals but would love to get into it. I was looking at building this pedal for a first project, but I was wondering if anyone would know how to make it with a boost "channel" on it? I love the sound of my mustang bass with a tiny bit of drive on it, so I was looking for one channel that just let it warm through the tube, and another for something a bit dirtier. Would it be simpler to just build two?
Cheers,
Mike
EDIT: I have just decided I am an idiot, the pedal (and whole thread) is already described as a boost. Perhaps my best option would be to build two into the same box, and have one running a bit harder than the other?
EDIT 2: My guitarist has just suggested putting in a switchable boost in front of the standard valvecaster circuit, with adjustable gain to drive it when needed. Would this be my best bet?
Sorry for asking such dumb questions!
Quote from: silentmike on May 18, 2009, 06:25:43 PM
EDIT 2: My guitarist has just suggested putting in a switchable boost in front of the standard valvecaster circuit, with adjustable gain to drive it when needed. Would this be my best bet?
Sorry for asking such dumb questions!
Mike,
This is exactly what I did in my first attempt with the valvecaster. I just modified the input and output caps to reduce bass frequencies. I've also built a dual valve circuit and I'm currently loving that, plus it's sweet having a pure tube circuit. At any rate, all of your ideas sound great.
Cheers,
Dan
Little update: I'm @ work now, and I've found a 12V/1A wall wart... could this do the job? ???
Quote from: lazerphea on May 19, 2009, 08:13:15 AM
Little update: I'm @ work now, and I've found a 12V/1A wall wart... could this do the job? ???
yes. that would work fine. the previous 11.6 you mentioned would probably work as well, but the farther your voltage varies from 12.6v, the shorter the tube life will be.
Well, I got it all together. Aside from the horrendously loud hum from the unfiltered power supply, it sounds great on my bass! Just need to get that power supply now...
Edit: HOLY CRAP! Just tried it with a battery to eliminate the hum (DEFINITELY is the power adapter) and this thing just sounds so fat and warm with the gain turned down! I couldn't tell before because the hum was just SO loud. Really glad I built this instead of an orange squeezer!
Quote from: bassmannate on May 21, 2009, 12:55:07 PM
Just tried it with a battery to eliminate the hum (DEFINITELY is the power adapter) and this thing just sounds so fat and warm with the gain turned down! I couldn't tell before because the hum was just SO loud. Really glad I built this instead of an orange squeezer!
:icon_cool:
Quote from: lazerphea on May 17, 2009, 03:14:55 PM
Ok, I had some time to make some experimentations, and here's what I've found:
- Just out of the adapter I read a voltage of 17.19V
- the output of the 7812 reads 11.01V
- if I add the 100uf caps to its input and output the voltage raises to 11.60V
- the same voltage is present an the pin N. 5 of the 12au7, when I connect the power to the circuit.
I get a very sloppy and uncomfortable sound out of it and the situation gets worse and worse as I play through the circuit; here's a soundclip of what I get after about 15 minutes of playing:
http://www.paoloscala.net/diy/12v.mp3 (http://www.paoloscala.net/diy/12v.mp3)
The sound degradates a lot...
So I tried to feed the tube with the 17.19V original voltage, and here's what I get:
http://www.paoloscala.net/diy/17v.mp3 (http://www.paoloscala.net/diy/17v.mp3)
Ignoring the hum, which I understood is given by the unfiltered adapter, the sound is still crappy and with no sustain at all... additionally, the tube doesn't lit up that much: I can see two filaments getting incandescent but that's it.
Maybe I should get a better tube (it's an Electro Harmonix)?
Thanks all.
EDIT: I forgot the adapter specs:
- it's a variable voltage adapter that spans from 1.5V to 12V, and I read: 500mA6VA(max) ??? :)
I just listened to your clips again and when I'm running from a plain unfiltered 12v power supply, I get EXACTLY the same hum as you do on you straight 17v clip. I hooked a 9v battery up to it and the thing was almost dead silent with the gain turned all the way up. It is most certainly your power supply. Don't give up! This really is a great overdrive! Just gotta get past that power supply issue.
While I'm looking, I guess I should ask what everyone here is using to supply their valvy with 9-12vdc. Obviously some are putting a 7812 or something in to regulate the power but are there any wall warts out there that will eliminate the hum without having to put more into the pedal itself?
I use this power supply, available from Maplin in the UK: http://www.maplin.co.uk/Module.aspx?ModuleNo=32746
It's rated at 500ma, but I find I can run up to four tubes from it with a combined draw of 600ma with no hum whatsoever. I have a few, I cut off the multi option/polarity plug and hardwire a 2.1mm plug for centre negative - avoids nasty polarity switching accidents!
Quote from: bassmannate on May 21, 2009, 03:46:50 PM
While I'm looking, I guess I should ask what everyone here is using to supply their valvy with 9-12vdc. Obviously some are putting a 7812 or something in to regulate the power but are there any wall warts out there that will eliminate the hum without having to put more into the pedal itself?
You have two options
1) Use a 7812 and a cap to filter and regulate the voltage coming fron whichever WW you may use - I use chines made, 4 euro WW and got no issues with them...
2) Use good WW, which are more filtered themselves and a 7812 (I'd put one inside anyway...)
Hmm...I'll have to do a bit more research. It's hard to find a wall wart in the US that's more than 12vdc (if I go the 7812 route) that's not made for a laptop computer. Having a hard time finding a 12vdc adapter that's filtered as well.
Quote from: bassmannate on May 21, 2009, 09:28:40 PM
Hmm...I'll have to do a bit more research. It's hard to find a wall wart in the US that's more than 12vdc (if I go the 7812 route) that's not made for a laptop computer. Having a hard time finding a 12vdc adapter that's filtered as well.
I recommend Dunlop ECB 006 for 18 VDC 1AMP available thru musiciansfriend or amazon. That's what I use and it is super quiet. But I still use a filter cap in my pedal.
http://accessories.musiciansfriend.com/product/Dunlop-ECB06-18V-Power-Adapter?sku=333100&src=3WWRWXGB&ZYXSEM=0
Quote from: shimster on May 21, 2009, 09:43:46 PM
Quote from: bassmannate on May 21, 2009, 09:28:40 PM
Hmm...I'll have to do a bit more research. It's hard to find a wall wart in the US that's more than 12vdc (if I go the 7812 route) that's not made for a laptop computer. Having a hard time finding a 12vdc adapter that's filtered as well.
I recommend Dunlop ECB 006 for 18 VDC 1AMP available thru musiciansfriend or amazon. That's what I use and it is super quiet. But I still use a filter cap in my pedal.
http://accessories.musiciansfriend.com/product/Dunlop-ECB06-18V-Power-Adapter?sku=333100&src=3WWRWXGB&ZYXSEM=0
Wow! That's great! 18vdc at 1.0A! I'm assuming that it's tip negative since that seems to be the standard.
Quote from: bassmannate on May 21, 2009, 09:46:21 PM
Wow! That's great! 18vdc at 1.0A! I'm assuming that it's tip negative since that seems to be the standard.
That's right. By the way, the reason I'm using this adapter is that this is what comes standard with the Dunlop DC Brick which powers my entire pedalboard. I've never used a different adapter except for that one time I tried one from Radioshack and got tons of noise.
After a little more searching, I found this: http://accessories.musiciansfriend.com/product/Visual-Sound-1-SPOT-Power-Adaptor-for-Wireless-?sku=151693
It's a bit less expensive, is filtered/regulated and I wouldn't need to put a regulator in my pedal! I'm gonna get one of these for the valvy!
Quote from: bassmannate on May 21, 2009, 10:09:00 PM
After a little more searching, I found this: http://accessories.musiciansfriend.com/product/Visual-Sound-1-SPOT-Power-Adaptor-for-Wireless-?sku=151693
It's a bit less expensive, is filtered/regulated and I wouldn't need to put a regulator in my pedal! I'm gonna get one of these for the valvy!
Nice find! Please let us know how well it works.
other sources for wall wart power supplies: At Goodwill, in the back with the electronics... there are baskets of crap remote controllers, power supplies, old curling irons etc....
if you have a big enough enclosure, you can get a 120v -> 12v transformer from mouser. I got a 500ma Triad transformer from them for $10 or so, and a Stancor 1amp that was a bit bigger for $12 or so. KBP005M-E4/45 is a integrated bridge rectifer that I've used ($0.58 ea) plus 2200uf/16v filter caps. not as fancy (or perhaps as quiet) as some good wall warts, but probably better than some of the cheap wall wart units.
well i am pretty much done with this project, and i must say it has been a SEMI-SUCCESS!!!!!!!!!!!!!!!!!! YAAAA!!!!!!!!!!!!!!!!!! WOOOOOO!!!!!!!!!! :icon_mrgreen: :icon_mrgreen:
i put in the voltage regulator and it cut down on about half of the hum. it sounds pretty nice though, still has some weird partials at times though, thats why im calling this a semi success. yet, i did enjoy every second of doing this and cant wait until i can afford another project.
pictures to come soon, and when they come you will realize why i have named my pedal (after a snide remark by my dad) the FrankenTube.
peaceful grooviness to all.
I hope it is alright that I bump this.
I recently read through the whole thread and got very excited and enthused about building such a pedal. I am an undergraduate Electrical Engineer and while we learn all about OP amp and transistor based filters and amplifiers we learn nothing of Vacuum Tubes. I've always thought they looked rather cool and were an interesting device. Now I've started to learn more about working with them and designing for them. This seemed like a great introductory project and it would have been but I screwed mine up right at the end. I had everything else wired and was soldering pin 8 of the socket when I applied too much solder and it ran up the recepticle on the socket meaning pin 8 of the tube would no longer fit in the socket. :icon_cry:
(http://doitle.markdelano.com/stuff/socket.jpg)
You can see the solder in the 8th pin receptacle. I'm not sure how to go about remedying this. I'm hoping some solder wick will work but otherwise I don't know what to do. I really wish I had gone with my gut instinct, put 8 wires from the socket to a bread board and done everything on there for testing purposes.
So in short, any suggestions on what to try? I really dont want to buy another socket and rebuild the whole thing if possible.
Solder sucker. Or just heat it up and blow it out while its still hot.
If you can find a piece of wire or something about the diameter of the hole, you can heat the solder and then shove in your piece of wire or whatever all the way through, if you can. Then let the solder cool, remove as much as you can, and then remove the wire. I do this when solder is clogging a lug on a pot that I don't want clogged.
I will try the thick wire method today sometime. If that fails looks like I'll be heading to radio shack to buy one of those bulb blowers. I sure hope I can get this figured out I was so excited about this pedal build. :/
You should still be excited. All of this stuff here is tons of fun and that is how it should remain. I remember when I first joined the forum, someone said that if this ever gets to the point where it isn't fun, take a step back and a couple days off. Great advice.
I got it working! I used the heat the solder and bang the socket to knock some of the solder lose giving me a small hole in the center of it. Then I heated the solder again and attacked it with a pushpin. The tube slid right in. : ) Unfortunately it doesn't sound too good but it works! That's the first important milestone. Next I get to troubleshoot and figure out why it sounds kinda crummy.
It hums loudly and has some very weird crackly sound to it. Also I can sort of hear an octave effect going kind of like an octave fuzz on some notes. I'd post a clip but I'm so terrible at the guitar it wouldn't be much use. Here's a picture of it though:
(http://doitle.markdelano.com/stuff/valvecaster.jpg)
The hummm could be from the power supply. Try using a battery and see if the hum goes away.
Here's a sound clip of it working. Like I mentioned before I'm pretty terrible :/ First is clean then Valvecaster on. Mine only works on maximum gain. Spin the knob down a little bit and there's no signal. Obviously something wrong there as well.
http://doitle.markdelano.com/stuff/tubes.mp3
Be careful as the tube engaged section is a little loud compared to the clean. See if you can hear the like... fuzzy octave effect. Is that supposed to be there or is something else acting up in my build?
It doesn't seem like I can edit my post but wow! I just got home for the father's day weekend and had my dad try out my Valvecaster. I must have had it setup wrong or something because it sounds amazing! It still hums really loud and I wired the pots backwards but it sounds great! I am renewed with vigor for this kind of endeavor. I can't wait to start my next build and also to get this one packaged up and switching in a nice enclosure. I think it may be going to my dad as a belated Father's Day present. I'll get a clip if I can manage but there's no easy way to record here at home.
Yeah Mike, good job! The Valvy is the kind of circuit that makes you wonder "how a circuit so simple can give out such nice sounds!!!" - It just needs a good filtering...so try to use a good Wall Wart and use the 7812/el.cap at the power jack.
I built several this way and virtually no hums or hisses...
Yeah I think I might go with the 7812. My dad has some 18V Wall Warts from Rechargable drills he said I could use. That should give me a lot more headroom. The 7812 can take a maximum of 35V input so 18V shouldn't be much of a sweat for it with a nice heatsink. Gotta get rid of that hum and figure out a way to prevent the peices that are built on socket from touching each other and shorting it out. Then add two switches (I figure Power and "Standby" :P Sort of like an amp) and I'll be ready to rock.
While you need one in a high voltage circuit, you can just avoid a standby in this low voltage circuit...
You may want to send the 12V from the 7812 to the heaters and the 18V (with some filtering indeed) to the plates (pins 1&6) for a little extra headroom.
Yeah that was my plan. 12 to the heaters and the full 18 to the plates. I thought if I wired it with two switches, a standby and an on then I could use the standby as a true bypass switch with only 1 DPDT and still have filament power and a LED switched on a second DPDT.
Basically, flick on power: Filaments start to glow and LED turns on, plates become powered.
Flick off standby: Rock and Roll
Flick on standby: True Bypass
I'm pretty much trying to avoid using a stereo input jack as a switch or buying a fancy 3PDT.
I like the idea of a "standby" true bypass switch, but my concern is whether you intend to turn the effect on and off during a song and if the standby will be a stomp switch or not. Just something to think about.
I'm no performer. :) I just like to mess around with these things. I was planning to use "Flick" switches like on the front of some amps. I'm not sure what to call them.
Upgraded to a slightly larger 9.6V Wall Wart and the hum almost entirely went away. Funny thing is the original one I was using was the Roland Adapter for my Micro Cube. This new one is some goofy Chinese brand that I don't even know where it came from. I'd have though it would work the other way around but you never know I guess. Also I realized that I forgot to solder one of the lugs on the volume pot... (I wonder why it cuts out when you touch anything?) I got my room mate to make this little demo since he can play better than I can:
http://doitle.markdelano.com/stuff/valvecasterdemo.mp3
This was a Ibanez RG120 into a Carlsbro Keyboard Amp with a line out into the sound card line-in recorded with Audacity.
First is clean, then 50% gain, then 100% gain. Still haven't boxed it up yet. I've been a little busy with other stuff. I bought an old tube radio to maybe try to build a little amp out of or something next. Thank you Valvecaster for getting me interested in the world of tubes.
Hi and thanks for letting me into the forum. Could some one please post the latest Valvy schematic using a 12AU7 with all of the newest mods and corrections. I have been searching the thread but am a bit confused as to the most updated information. Thank You.
Quote from: Pigyboy on June 27, 2009, 07:02:20 AM
Hi and thanks for letting me into the forum. Could some one please post the latest Valvy schematic using a 12AU7 with all of the newest mods and corrections. I have been searching the thread but am a bit confused as to the most updated information. Thank You.
Yeah, this thread is rather long now! Maybe someone should gather all the key information and start a new thread with a link back to this thread.........
Quote from: frequencycentral on June 27, 2009, 07:38:01 AM
Quote from: Pigyboy on June 27, 2009, 07:02:20 AM
Hi and thanks for letting me into the forum. Could some one please post the latest Valvy schematic using a 12AU7 with all of the newest mods and corrections. I have been searching the thread but am a bit confused as to the most updated information. Thank You.
Yeah, this thread is rather long now! Maybe someone should gather all the key information and start a new thread with a link back to this thread.........
That would be a beautiful thing..
I think I found what I was looking for on page 53. Looks to be the latest layout.
Thanks
I built mine off the schematic in the very first post of this thread it works well. I haven't decided if I'm happy with the way it sounds though or if I want to try doing anything else like adding clipper diodes or something. I could probably add a switch to add the diodes and take them back out when I just wanted a tube overdrive right? Also thinking off adding a full wave rectifier to try to get a simple octave effect out of it though I haven't done enough research yet to put that plan into action.
Any suggestion using matsumins valvecaster layout on page 53 to voice it for a bass guitar?
Hey all.
Started work on my Valvecaster 12AU7 today. It's not going great though. I have true bypass, but no effect output. However, i think i MIGHT have the pins wrong on my valve. When you look at the image below, the one that ISN'T SOLDERED TO ANYTHING is supposed to be pin 9, but i think i have it backwards like. I'm working off of this schematic:
http://www.beavisaudio.com/projects/ValveCaster/MatsuminValveCaster.gif (http://www.beavisaudio.com/projects/ValveCaster/MatsuminValveCaster.gif)
and i made this vero:
(http://i40.tinypic.com/2qxw3zq.jpg)
And as a bonus, here's pics :)
1. The valve. I forgot to order a socket lol, but PLEASE check if i have the pins right. Is the one that's not soldered 9 or 1?
http://i41.tinypic.com/33nayyr.jpg (http://i41.tinypic.com/33nayyr.jpg)
2. Slightly different pic of the tube
http://i42.tinypic.com/2eol010.jpg (http://i42.tinypic.com/2eol010.jpg)
3. Top side of the board
http://i44.tinypic.com/ip33u8.jpg (http://i44.tinypic.com/ip33u8.jpg)
4. Underside of the board. Black lines indicate track cuts.
http://i42.tinypic.com/25hzn7p.jpg (http://i42.tinypic.com/25hzn7p.jpg)
5. Pot Wiring
http://i39.tinypic.com/35d836c.jpg (http://i39.tinypic.com/35d836c.jpg)
Any help would be greatly appreciated.
EDIT:
also, the tube does glow, so i don't think it's a problem there.
You have pin 9 unsoldered. That is correct. I just checked it against my valvecaster. Not sure what's wrong with yours. Maybe take voltage readings at each pin and I could compare them to mine? Might tell you where to start troubleshooting.
i would if i had a multimeter....
did you build yours on vero? there's so many vero's out there that i ended up making my own, but it'd be handy if i had another that's verified to check it off.
I built mine on socket. It's sad because yours looks a thousand times better than my build. : )
(http://doitle.markdelano.com/stuff/valvecaster.jpg)
hmmm... quick question. The original schem has an electrolyte, but all the vero's just use a standard cap. which should i be using?
As you can see in mine I used an Electrolytic. Don't know that that would cause your build not to work though...
@ trad3mark: I notice you're using a ECC81/12AT7. The 'standard' Valvecaster tube is a ECC82/12AU7. I'm not sure if anyone has used a 12AT7, but you may find it's an issue. Also, I've posted volategs from my working Valvecaster at various points in this thread - be aware that your voltages may differ as you're using a different tube type.
nah it's been confirmed with 12AX7's, 6111's, 12AY7's, so it's not the tube type. it's gotta be a wiring issue of some sort. :icon_mad:
trad3mark welcome in this fabolous TUBE world! And also thank you for another vero layout - it might be handy to someone...
I made a much smaller layout some time ago, just search for it and some variations (toneless, etc) in the gallery, in my personal folder. Those layouts are quite smaller and all verified by myself and some other fellas around, so you can use them as a guide if that can help you!
Pigyboy, I successfully use my Valvy #001, which has standard values and no tone control, in my band. I play the bass in a Queensryche tribute ATM and the Valvy boosts the signal in the best way, and doesn't cut the low frequencies. I dunno about the other layouts, I know that mine are verified - feel free to take a look at them.
http://www.aronnelson.com/gallery/main.php/v/Renegadrian/
sigh...
tried the vero you suggested, and still nothing. the tube doesn't even glow (it did on a previous vero). Very disheartening, but i'm going to give it a rest for the day. I've college work to do.
i'll post up some pics later, maybe someone could take a look.
Be sure about pins 4 and 5. one must receive 12V and the other must be tied to ground.
It seems you counted the pins in the correct way, anyway you may want to check the link below for reference
(http://www.camillobella.it/immagini/link0.gif) (http://www.dogstar.dantimax.dk/tubestuf/pinout.htm)
I just received an email from an italian builder, he wanted to share his experiments and the results he has with different tubes...
ecc82 electro harmonix = perfect sound as expected
ecc82 electro harmonix gold pin = less gain
gt 12ax7a = bad
sovtek 12ax7 = bad
gt 12ax7wc = little overdrive and gain but good sound
vintage ei yugoslavia 12ax7 = lots of gain and harmonics
I tried to use an ax7, I have a recent JJ around, but it gave an horrible sound, and discarded the idea of using one in a Valvy...I then just discovered that SOME ax7 can be used with good results...
ok, so i'm starting to get somewhere.
Regenadrain, i'm more or less working off your VC vero with the tone dial. The only difference i made to it is that i added a line at the top, where i have all my grounds running to. It's just to simplify that in case i miss a ground. I've noticed one mistake since i took the pictures below, and that's that pin 5 was not grounded. I fixed that and it's giving the valve that old familiar orange glow. HOWEVER, i still have no fun overdrive. I don't think it's an issue with the jacks, cos i'm getting true bypass cleans like. Here's a load of pics anyway. I feel i'm close like... :( I've included a bunch of pics. It's easier to help with tonnes of pics, right?
1. Start off on a good note. :) the gental glow of a tube. ;)
http://i43.tinypic.com/aorl75.jpg (http://i43.tinypic.com/aorl75.jpg)
2. Topside of the board. The black line at the top is my "Ground line". There's also a spacer line between that and the top of Regenadrain's vero, so it might be easier to check it by working from the bottom upwards.
http://i39.tinypic.com/1t5vo9.jpg (http://i39.tinypic.com/1t5vo9.jpg)
3. Tube wiring. A bit of a blurry pic, but for reference to the board.
http://i44.tinypic.com/2qw2338.jpg (http://i44.tinypic.com/2qw2338.jpg)
4. The 1uF cap between board and Tone 1, which then goes to ground. I put it on a tiny bit of board for convenience. ;)
http://i42.tinypic.com/2lo54i9.jpg (http://i42.tinypic.com/2lo54i9.jpg)
5. The 10nF cap between vol 3 and tone 2
http://i39.tinypic.com/2u6g4er.jpg (http://i39.tinypic.com/2u6g4er.jpg)
6. The 10nF and Vol pot. The purple wire goes to the correct pin on the switch for output.
http://i42.tinypic.com/2sbmzqq.jpg (http://i42.tinypic.com/2sbmzqq.jpg)
7. The gain pot. 1 Goes to ground on board and 2 is coming from pin 3 on the tube.
http://i39.tinypic.com/10cvi13.jpg (http://i39.tinypic.com/10cvi13.jpg)
8. And finally, the obligitory shot of the board underbelly, with the mystical magical ground line at the top. :)
http://i43.tinypic.com/5noncy.jpg (http://i43.tinypic.com/5noncy.jpg)
Again, i reiterate that pin 5 is now connected to ground (my mistake!). I have buzz/hum when i touch certain points of the whole scheme too, apart from the obvious ones like the hot input jack wire etc. :P
Ok, looked at this one http://i39.tinypic.com/1t5vo9.jpg and http://i43.tinypic.com/5noncy.jpg
two things I'd like to point out.
1) the 47nF cap that lays horizontal (to the copper tracks) must have a break between its pins/legs.
The pic is not clear enough so I can't say there is that break in the track.
2) Also the res. placements is not so clear...Let's try to explain their positions with words...
Starting from the left
* 470k - pin7 and one part of the other 47nF <----> ground | It should be ok
* 1M - pin2 and the output of the first 47nF <----> ground | I cannot understand wheter it's correctly connected to ground...
* 220k - pin1 and one part of the other 47nF <----> 12V | that seems correct.
* 100k - pin6 <----> 12V | that seems correct.
So I believe the problem is where that 1M res is connected...It should go to ground together with the 470k, but my eyes don't seem to get that...
PS try to write my name correctly or I won't help you anymore!!! :icon_twisted: :icon_evil:
(kidding...)
sorry Renegadrian :P
yeah i had a little look there this morning, and noticed a few mistakes. Here's a pic to update:
http://i42.tinypic.com/2vx24k5.jpg (http://i42.tinypic.com/2vx24k5.jpg)
So just to clear some things up:
1. There is a cut between that 47nF horizontal cap.
2. The resistors:
a. The 470k is going from (at the bottom) Pin 7/47nCap 2 TO Pin 4/Ground/1M (At top, and to 1M via jumper)
b. The 1M is going from (at the bottom) 47nCap1/Pin 2 TO Pin4/Ground/470k (At top, and to 470k via jumper)
c. The 220k is going from Pin 1/47nCap2 TO Pin 5/9V+/100k
d. The 100k is going from 9V+ to Pin 6
Which all seems correct, right?
Yeah, it seems correct...I'd advise you to run it at 12V.
not much point doing that though if i've no output at 9V, right?
Just to verify, if i had a problem with one of the jacks i wouldn't get any signal on true bypass, right? and if it was an issue with the lug with the -ve, the tube wouldn't light up, right?
Hi boys!
I read this topic for a year, but I couldn't register here. Why? I don't know... ???
I was searching for a tube preamp. I build a guitar amp for myself and I wanted a tube preamp.
Do you know The Hood? It's the best low-voltage preamp, I think.
http://www.pdfelectronics.com/the_hood_a_custom_pre_amp_design.htm
It has a very good working tone stack. Boost and clean/dirty switch...
It has warm and very detailed sound. From the clean sound to hard overdive... Great!
I'm using it with stable +24V power (7824), because the power amp has a +-26V supply.
(How can I insert image?)
Attila
Chris, the guy who developed the Hood is quite active with tube stuff here. He's a good guy with great designs. Welcome to the forum.
Hmmm...
anyone got some Voltage Refs for the 9v version, preferably Renegadarian's Vero version with tone?
Quote from: trad3mark on July 03, 2009, 02:11:22 PM
Hmmm...
anyone got some Voltage Refs for the 9v version, preferably Renegadarian's Vero version with tone?
The only voltages in this entire 65 page thread are the ones I've posted a few times, taken at 12 volts. Yours at 9 volts will just be 75% of mine. Post up your own voltages and we'll detect what's amiss.
so where should i check? (this is my first go of my new multimeter, and my first set of voltage refs! :) )
Quote from: trad3mark on July 03, 2009, 02:34:58 PM
so where should i check? (this is my first go of my new multimeter, and my first set of voltage refs! :) )
Set the Gain, Tone and Volume to maximum. Hook up the black probe of your DMM to ground and use the red probe to take readings from each of the tube's 9 pins.
Here's mine:
Pin 1: 3.02v
Pin 2: -0.518v
Pin 3: 0.00v
Pin 4: 0.00v
Pin 5: 11.97v
Pin 6: 8.21v
Pin 7: -1.285v
Pin 8: 0.00v
Pin 9: 5.91v
Great. Thanks FC. I've to take the dog out for a walk really quickly, i'll check it all when i get back. :)
Right, not sure if i'm doing this right:
Black lead is connected to COM on DMM. DMM is set to 20V, Black Probe to Ground on Output, 9v Battery connected, input jack connected, and i put the red probe on the pins giving these readings:
1. 6.47
2. -0.02
3. 0.00
4. 0.00
5. 7.83
6. 7.09
7. -0.02
8. 0.00
9. 3.86
is that done correctly?
Firstly, your battery is only reading 7.83 volts, that's probably not enough, as the heater requires 12 volts. I personally feel that 9 volts isn't enough for the heater really. Valvecasters eat batteries for breakfast. Consider using a regulated wallwart, preferably a 12 volt one.
Secondly, your voltage at pin 1 is way too high. Double check the value of the resistor connected to pin 1, it should be 220K. Your pin 6 voltage is a little high too, but solving the issue at pin 1 is the key right now.
i checked that resistor. it's 220k, definitely. I checked the voltage at both ends, and there's a drop, so it's soldered correctly too.
here's a pic of the board (top side)
http://i44.tinypic.com/2nsrgur.jpg (http://i44.tinypic.com/2nsrgur.jpg)
and the tube wire colours are:
1 grey
2 white
3 red
4 purple
5 orange
6 blue
7 yellow
8 green
any way i could check the pots/jacks with my multi?
built it anew with fresh new parts. Still no output, but here's some new voltage readings:
PINS:
1 6.08
2 -0.01
3 0
4 0
5 7.39
6 6.69
7 0 <----- DISASTER!?
8 0.42
9 3.58
sadface...
Ok, you battery is now giving out 7.39 volts, I don't think that's enough to get the heater hot enough to start boiling off electrons. Consider using a fresh battery or better still a wallwart. Also, as I said earlier, your voltages will probably not match mine as you're using a ECC81, which will certainly give different voltage readings at the plates. As an example, running from a 12 volt supply a 6111 has a pin 1 voltage of 9 volts in this circuit. Compare this to the ~3 volts pin 1 voltage of a 12AU7.
well, the 9v thing aside, cos it's been done with 9v before, are there other things i could check which would be causing problems?
Quote from: trad3mark on July 04, 2009, 07:01:48 AM
well, the 9v thing aside, cos it's been done with 9v before, are there other things i could check which would be causing problems?
Quote from: frequencycentral on July 04, 2009, 04:50:50 AM
Ok, you battery is now giving out 7.39 volts, I don't think that's enough to get the heater hot enough to start boiling off electrons.
You haven't got 9 volts even, you've got 7.39 volts and counting. The first Valvecaster I made was battery only, it didn't take long for it to drain a battery low enough to be gatey and blarty. The tube you're using has a 12.6 volt heater requirement, it's getting 7.39 volts ATM. That's a problem you could solve before all others.
Actually you shouldn't consider at all the use of a battery in a Valvy. If the tube is a 12AU7 and requires 12V, give it what it needs...Otherwise use 9V from a wall wart using a 9AU7.
Every other argue is useless if the circuit hasn't got the proper voltage (regulated and filtered).
ok so i found a wallwart that'll do 9v or 12v. which should i go for first?
Quote from: trad3mark on July 04, 2009, 10:37:52 AM
ok so i found a wallwart that'll do 9v or 12v. which should i go for first?
Go for the 12 volt choice. Best one for the heater. Make sure you hook it up with the correct polarity - test it with your DMM first.
HURRAY!!!!!! :D:D:D:D
Ok first off, COLOSSAL thanks to both Renegadarian and Frequency Central. I have to say thanks before i go into this at all.
I have boost/od.
Running it on 12V at the moment. The boost is great, and the od.... It's VERY subtle. But i like it. So now i'm just wondering though, to get a bit more out of it, what about some sort of a booster before hand? can, for example, a rangemaster vero/schematic be changed to run on the same 12V rail?
Cool! 8)
Those tubes sure like wallwarts better than batteries! The OD is probably subtle as you subbed the 12AU7 for a 12AT7. Would you please take (and post) voltages again now that it's working - just curious as to what the plate voltages are with teh tube you used.
You have a broud choice of boosts to drive it harder, Adriano will be a long soon to say 'Tillman', I like an LPB, some folks even like my own very humble Pentaboost or 5840 Booster.
VRefs for yew! ~(i think the taper is backwards on either gain or tone, but this sounds right)
1. 9.62
2. -0.28
3. 0
4. 0
5. 12.12
6. 9.99
7. -0.13
8. 0
9. 6.03
As for boosters, i had an interesting idea....
the way i was going to do it was put in a second circuit that runs on a 9v battery with super low current draw. This way, you're basically getting 2 boosts/od's in one box. It'll be done in such a way that you could either have just the VC on, the VC and Boost on, or just the boost. There'll be a DC jack for the 12V, but because i dont have and Voltage Reg IC's, you'll need the battery for the boost. If you don't have a battery, the VC will still work off the plug, and if it's not plugged in, but there's a battery, you'll still be able to use the boost. Totally true bypass, 2 switches, 4 dials. DESPERATELY need opinion on this one.
Interesting, those look just like a 6111 Subcaster set of voltages, thanks!
Did someone already suggest a Tillman b4 the Valvy?! :icon_smile:
any ideas for a booster i can run off the 12V rail without one of those voltage regulator ic things to get 9v? like if i had a 9v booster, and put a big resistor from the 12v rail to the 9v circuit, could i do that? (sorry if it's an unclear explanation...)
Most boosters (in fact most circuits) designed for 9 volts will work at 12 volts. I built a footswitchable LPB into my second Valvy, running at 12 volts. I like the sound of it a lot.
fantastic. that makes things so much easier! i just tried the VC with my Super Hard On before it. Sounds MUCH nicer. So i think i've parts for a Rangemaster. I assume i just build it the normal way, but run 12v into it?
Rangemaster + valvecaster is very nice :icon_twisted:
Quote from: trad3mark on July 04, 2009, 01:25:14 PM
fantastic. that makes things so much easier! i just tried the VC with my Super Hard On before it. Sounds MUCH nicer. So i think i've parts for a Rangemaster. I assume i just build it the normal way, but run 12v into it?
Isn't the stock Rangemaster PNP and positive ground? That would be a problem running of the same supply as the Valvy. Though you could do the modified (and NPN, negative ground) Rangeblaster: http://fuzzcentral.ssguitar.com/rangemaster.php
I finally figured out how to simulate tubes in LTSpice. Thought I would simulate the Valvecaster. Does this look right? If so, look at that low frequency BUMP!
(http://doitle.markdelano.com/stuff/valvecasterschem.jpg)
(http://doitle.markdelano.com/stuff/valvecastersim.jpg)
HUZZAH!! I now have it all going on breadboard!
FC, the rangemaster is PNP yeah, but i got a vero for the NPN one, so all is well. :) I tested a bunch of NPN's i had, which gave these results:
2N3904 Hfe=214; Too trebly, very flat sound
Bc107 Hfe=193; Rounder, More Fuzz/Distortion/Gain even at low levels
2n2222 Hfe=248; Similar to BC107, slightly more fuzz, less silicony
C2655Y Hfe=181; high level Gain. Distortion at any levels of boost
C2878b Hfe=226; Grainier, not very crisp/clean
C1815gr Hfe=241; V.Low gain. Almost no od at max boost
With whatever i use though, the VC does give much better results, it kinda needs a boost like.
I think i'm going to go with either the 2N2222 or the BC107. That being said, the C2655Y would be just awesome in some sort of fuzz like a Rat or similar. Going to get breakfast, then i'll start on the final vero.
Quote from: trad3mark on July 05, 2009, 06:49:31 AM
...the C2655Y would be just awesome in some sort of fuzz like a Rat...
???
hmmm...
slight, minor issue with my VC. It's working great, and i really love it, but, there's a slight issue with volume.
With ALL my other pedals, be them build or bought, when volume's at 9 o clock, it's more or less the same volume as clean/when it's switched off. Not with the VC. It needs to be at least at 9 o clock, and even when it's at max volume (and max everything actually) it's still not as loud as if i just use my SHO on max on clean. SO, because output is coming from lug 2 of the volume (which is a 100k pot) could i just swap the 100k pot for something like a 50k pot to get more volume? Or is there something easy i can do to increase the volume? I reckon it's roughly a half or a third of what it should be.
cheers,
tm
Swapping the volume pot for a 500K will give you slightly more volume...........hmmm, I was going to say your build may still have an issue somewhere, but yours is a ECC81 tube, so has less gain than ECC82 anyway. It might also be worth your while tinkering with the values of the two plate resistors, as what works for a ECC82 may need tweaking to work with a ECC81.
going for a pot of HIGHER value gives more volume?! :icon_confused: how come it's not a lower resistance one?
Because with a higher pot value you're putting more resistance between the signal and ground. Think about it, if you short the signal to ground you have zero resistance and therefore zero signal.
oh.... ok. I have a 470k pot. I'll try that. Cheers FC. :)
Just got a package from the mailman. 9 12AT7s. Initially put one in the valvecaster to make sure I wasn't just sold glass ornaments and it did work :P I didn't really hear much of a difference except for strangely... it was quieter than with the 12AU7... Similar to what we were discussing in the Promiscuous Girlfriend thread with the 6112 being quieter than the 6111 even though the 12 has more gain. Later today maybe I'll convince my room mate to record some clips of the valvecaster with the 12AU7 and the 12AT7 for comparison.
Quote from: doitle on July 14, 2009, 02:12:32 PM
Later today maybe I'll convince my room mate to record some clips of the valvecaster with the 12AU7 and the 12AT7 for comparison.
That would be great to hear !!
Mike, it seems that the greater the gain value of a tube, the more voltage they need to work good...
I made some little experiments with the 12**7 I got (AU, AT and AX) - AU work quite good at low voltages, AT require a little extra push and I still haven't managed to make an AX sound decent with my voltage multiplier (50V)
How would I make a Valvecaster, the 12Au7 version, into a clean boost? I'm not looking for overdrive.
I believe Rick made some experiments to get unity gain or something - actually the Valvy gives a clean boost with the gain pot turned all the way down, so you may expect the same result by swapping that pot for a fixed res., say 47k <--> 100k
Quote from: azrael on July 15, 2009, 04:22:35 AM
How would I make a Valvecaster, the 12Au7 version, into a clean boost? I'm not looking for overdrive.
Someone (I forget who) mentioned this way back near the beginning of the message:
The nicest clean sound I've found so far, is with the following mods:
R2 = 100k
R3 = 47k
C1 = 0.1uf
Remove C4 and VR2
Of course, more voltage will give you more clean headroom, so if you really want a good clean boost, I would look at boosting your 9V to something higher (several times higher using a charge pump, perhaps).
sorry to come back to my earlier problem of volume.
I put in a 470k pot for volume, and it made SOME difference, but it still needs to be at least 12 o'clock to match the off volume. Any ideas of what i could change in the circuit to boost the volume? Still running on 12V by the way.
There's not much you can do to boost volume without either increasing gain or voltage. You could do a 1M pot at the end for volume, though if I were you, I would get myself a TC1044 charge pump, put the 12V in, add a few caps and diodes and get yourself 25 or 34V on the plate. It will make a world of difference.
I run a 12AT7 in mine and don't have a problem with volume - bear in mind that every pedal is different, and '12 o'clock' on one won't be the same on the next. But you should definitely be getting way above unity if you crank the volume pot right around. If not, then you have a problem. From memory, mine gets unity gain at about 12 o'clock-ish as well, so it sounds right to me.
Just tried running the LPBass-1 into my valvecaster here... It sounds awesome! Now I REALLY want to get these things packaged up so I can show them off! :P Also for the people asking if the filaments glow brightly, get yourself a GE 12AT7 and run it off 12V... The thing is like a lightbulb!
I can't wait to get these bundled up as real pedals and start on my next project!
Hi first post here and I have to say this is a great site.
I had enough parts laying around to build the Matsumin Valve Caster this weekend and it sounds great. Right now I'm swapping out some parts so i have a couple of questons.
1. Is C3 supposed to be an electrolytic cap. It looks like some of the layouts use different values and not electrolytic.
2. On the below quote I'm confused as to what VR2 is.
"The nicest clean sound I've found so far, is with the following mods:
R2 = 100k
R3 = 47k
C1 = 0.1uf
Remove C4 and VR2"
Thanks :icon_biggrin:
Hi there and welcome!
Right, here's the answers...
As for that cap, you can use either, so polarized or unpolarized are quite the same - I used both and got no differences...
VR2 (variable resistor) is actually the TONE pot - So you have to build the toneless version (and if I read the previous pages you know that many fellas including myself think it's better without...)
Hope it helps!
I was thinking of removing the tone pot from my valvecaster because it doesn't do much when you turn it anyhow. Maybe when I get back down to school I will remove it.
Been there already...I am sure you won't miss it...All my valvies are toneless...
Else you should breadboard a more functional tone control and try it out...but the stock one just sucks!
There's a new dual 12au7 design for bass over at Tube Town: http://www.tube-town.net/diy/lov/lov04-sugar_box.html German language only ATM, but an English version should be out soon. Nice looking PCB.
thx Rick for the suggestion...
Basically it says that it came from some ideas in their forum - that yes it features 2 12AU7 tubes but is rather simple design, and you can have a good bass system coupling it with a chip power amp...and that as other low voltage tube projects, a good power supply is reccomended (they also sell a dedicated power supply)
gotta study this circuit...
As I am writing this, I want to share my experience with my Valvy (my fist one, toneless, 12AU7, with 7812/100µF)
I use it with my bass, so happy with it...but at the end of our weekly reharsal, the last 30 minutes, it becomes dirty and unstable with some hum added...Maybe someone experienced the same problem?!
Tried a different tube? Maybe it needs replacing. Was it new or was it NOS?
It has a EH tube, bought new as I began building it (so 1 and ½ year ago) - I have to try another tube, that one never satisfied me...
Maybe test the voltages too then. And reflow the joints. I bet your soldering has improved in 1 1/2 years!
Yeah I have to give my baby some attentions and care...I'll report if anything goes wrong/strange...
Renegadrian how is the regulator heat sunk, if it is at all?
It could be possible it is overheating and failing. Then you would be using some form of "dirty" voltage I would think. That would defiantly cause hum, as we all know very well.
The flat side of the 7812 lays onto the inside of the enclosure, so the enclosure itself should act like an heatsink?!
I was thinking the same, maybe the 7812 works flawlessly until it gets overheated?! I'd have to touch it to feel its temperature...
Bolt it to the enclosure.
Hi, I'm building a valvecaster with a sparkle boost inside it, but I'm having some problems with the switching... (decided to got for something adventurous for my first build!) I've got a 3PDT for the main on/off which I believe is wired in right for true bypass and the rest, and I've got a 4PDT to change between valvy or sparkle boost + valvy. My LEDs light up and the valve gets warm, but I think I was misinformed by my guitarist when he drew me a wiring diagram. Anyone know how to go about doing this? Also, the pedal won't work with my power supply, only batteries. Any ideas there as well?
First, you don't need a 4PDT, you could do it with a DPDT. Also, what do you mean by doesn't work with power supply? Did you wire it for center negative? Also, if you could post a drawing of the wiring diagram, we would be happy to take a look at it and see what we can find.
Also, what is the rating of your power supply? If there isn't enough current supplied it won't work.
Right, sorry I didn't know what you guys needed to have. My guitarist thought I needed the 4PDT switch...
Here's the diagram I've worked off:
(http://i782.photobucket.com/albums/yy108/silentmike87/mikes-1.jpg)
When I say it doesn't work with the power supply it literally does nothing. It'll light up when connected to a battery but as soon as it gets connected to the power supply it doesn't do a thing. The supply is a regulated 9V one with center negative. The socket is wired in right (I've modded my big muff to have one and that works fine with the same supply).
Right, I think I'm going to blame some of this on my guitarist's unverified vero layout and just build the valvecaster on the back of the socket as I had intended to do anyway! Does anyone know of a vero layout for the sparkle boost or am I asking in the wrong place?
Cheers!
Mike
just a quick search in the gallery and you'll find what you need...
Aha! Found it! Thank you very much. Now to take it all apart...
Ok, I just got an absolutely INSANE idea for a valvy. Please be prompt to shoot me down if this is the dumbest thing you've ever heard of.
What if we were to replace the 1/4" jack out with an XLR and turn it into a phantom powered direct box? it would give us +48v to play with and we wouldn't need a power supply if we were going into a house sound board.
What would be involved in bringing the valvy up to line levels to go direct into a board? Does phantom power provide enough current to power the valvy?
There is no possible way to get enough current out of phantom power if you are trying to run the heaters off of it. If you were to run just the plates, sure, there's enough juice for it. I think you would have some issues with impedance matching, plus you wouldn't get the benefit of a balanced signal unless you put in a transformer. So in short, could do it, not without a separate power supply, but could (means a transformer and some other things). Worth it? In my opinion, no.
Ok. I figured that phantom power wouldn't supply enough current for the heaters. Just out of curiosity, what is typically the max. current of most phantom power systems?
14mA. Not much ;)
Hey guys, here's my effort. First off, thanks to all those who have participated and provided great ideas on this thread! :D I am indebted to Matsumin, Beavis and all those who have followed.
OK, so my "Valve'd" has a few mods as you will see by the schematic below:
* The "Clarity" switch. As suggested by Krinor - refer http://www.diystompboxes.com/smfforum/index.php?topic=63479.msg518458#msg518458 (http://www.diystompboxes.com/smfforum/index.php?topic=63479.msg518458#msg518458)
* I added a power on/off switch and run the heaters at 12.6VDC & the plates at 24VDC using a customised power supply on my pedal board that has all sorts of outputs.
* The Gain Pot bypass for clarity at lower gain suggested by Ripdivot - refer http://www.diystompboxes.com/smfforum/index.php?topic=63479.msg516969#msg516969 (http://www.diystompboxes.com/smfforum/index.php?topic=63479.msg516969#msg516969)
* Various filter cap and plate resistor mods to vary gain and frequency range
I hope this helps some other people. I really enjoyed this project - especially the extra hardware for the enclosure. I also think running the pedal at the higher voltages helps the structure of the sound, but this thing will still run nicely at 9VDC on both power inputs - versatility is what makes this circuit so special! Extra thanks to Renegadrian, who seems to be keeping this whole thread together! ;)
Excuse my Beavis-style schematic . . . :P
(http://macturkey101.googlepages.com/ValvedSchem.gif/ValvedSchem-full;init:.gif)
I went for the all polished chrome/stainless look and added a high intensity blue LED up the centre of the valve socket that lights up when the effect is on - mmmm, blue! :icon_lol:
(http://macturkey101.googlepages.com/Valved3.jpg/Valved3-full;init:.jpg)
(http://macturkey101.googlepages.com/Valved4.jpg/Valved4-full;init:.jpg)
An nice old Mullard 12AU7 for that extra creamy goodness! :P
(http://macturkey101.googlepages.com/Valved2.jpg/Valved2-full;init:.jpg)
Obligatory gut-shot
(http://macturkey101.googlepages.com/Valved1.jpg/Valved1-full;init:.jpg)
And finally, the vero I used:
(http://macturkey101.googlepages.com/ValvedVero.png/ValvedVero-full;init:.png)
Cheers,
turkey101
Wow that is a great looking build, very classy.
Like the PVC(?) wire and your routing.
I don't understand your clarity switch though. It looks like when the switch is open you won't get any output.
Ah totally missed the schem. Very cool control, I get it now. :icon_biggrin:
can someone please check my layout...
(http://i297.photobucket.com/albums/mm230/w437776/valvecaster.gif)
(http://i297.photobucket.com/albums/mm230/w437776/valvecasterpcb.gif)
This is my first time posting on DIY stompboxes (I think). Now I blame you guys for getting me overly obsessed on this.....
Nah just kidding, I love this site. :icon_mrgreen:
I was planning on building the Real Mctube, but I totally changed my mind when I found out about the Valvecaster. I don't have money yet to buy the parts, since I just used it to make a gain boost, but I'm just here to figure things out and make my plan. So far I'm thinking of getting a 2-amp 25.2v transformer and regulate it to 12v. Tell me if there's any problem with this.
As a some of you guys done, I'm gonna place a high brightness LED underneath the 12AU7 (Turkey101, yours looks gorgeous!), but I'll be using a bicolor LED, making RED indicating bypass and BLUE as active. The blue LED will light up to the guitar signal, so it will react to the guitarist's picking. You guys may know this as the LED Twinkler on YouTube by JeonJoe, I found out how to do this with only just a cheap opamp and capacitor which can be found at radioshack. Having the tube light up to the sound of your guitar would look amusing :3
As you guys can tell, I'm probably one of the biggest DIY guitar guru at my age, see here for proof:
http://www.youtube.com/user/duy1337guitar
There are actually a ton of members here about your age, but welcome all the same. The issue I see with regulating a 25.2V wall wart is that the 150mA needed for the heaters (at 12.6V) will mean you have to dissipate about 2W from your regulator, which means a big heatsink to keep it from shutting down. Other than that, I can't think of anything, though 25.2V implies that is going to be an AC wall wart, correct? If that is the case, you are going to be dropping more like 3W to regulate, but gets great plate voltage.
Calling yourself a guru :icon_lol:
The LED sounds cool
Quote from: Ripthorn on August 18, 2009, 11:27:14 PM
There are actually a ton of members here about your age, but welcome all the same. The issue I see with regulating a 25.2V wall wart is that the 150mA needed for the heaters (at 12.6V) will mean you have to dissipate about 2W from your regulator, which means a big heatsink to keep it from shutting down. Other than that, I can't think of anything, though 25.2V implies that is going to be an AC wall wart, correct? If that is the case, you are going to be dropping more like 3W to regulate, but gets great plate voltage.
I said I'm going to be using a 25.2v transformer from radioshack. This one:
http://www.radioshack.com/product/index.jsp?productId=2102703
2 amps is more than enough to power everything I need for this project.
I'm gonna use a 12v voltage regulator so I don't get any noise or hiss. Just yanked off some heatsinks from scraps just a while ago. I think it be cool to have 24v but a 24v voltage regulator requires at least 27v DC supplied. I'll be using the 12v for the circuit itself and the heater. If I'm informed correctly, it should be safe for the heater to have 12.6v plus/minus 10% (so ~11.3v to 13.9v). Better than using 4.5v like from the original schem.
Maybe I could just make a switch for changing plate voltage. Make it switch between the regulated 12v and the 25.2v directly from the transformer. If there's no hiss or noise that i'd get annoyed of, I'll probably keep the switch.
If any of you guys are interested on how the LED Twinkler works I can post a drawing, super simple and would look great on projects. Maybe looks even cooler with the light emitting border shown on this site :icon_cool:
Quote from: DUY1337GUITAR on August 19, 2009, 01:04:53 AM
...Make it switch between the regulated 12v and the 25.2v directly from the transformer.
not a good idea... :icon_biggrin:
Here's the deal, you are going to totally fry something if you try to use that transformer with a voltage regulator. You will need to go from that transformer, through a bridge rectifier, smoothing caps and chokes/resistors then into your regulator. Rectified, that transformer will supply 35V. So you are going to be dropping 23V ish over your regulater. At 150mA, that comes to 3.5W, which is going require a really hefty heatsink with some good compound. You really should study up on power supplies first. Here are some faults with your current approach and their solution:
1) You HAVE to rectify your 25.2VAC to DC, you can't just run AC into a regulator, that thing will fry quick.
2) You NEED to filter after rectifying, otherwise you will get hum and noice up the wazoo.
3) If you use a 12V regulator on the rectified output, make sure the heatsink on it never gets much more than fairly hot to the touch. Blazing hot means it is working too hard to dissipate the heat which can also introduce hum into your signal.
4) To use 12V on your tube heaters, you will have to use different pins on the tubes, the one for the heaters in series.
5) Number of amps from your transformer in this case is a non issue.
If you can't find a heatsink that is appropriate, you could probably rectify one of the 12.6V taps and regulate that, but the smoothing caps and resistors are still required. Again, I should stress that if you want to do these things you propose, you have to read up on power supply design, or you will have youreself some nicely fried tubes/ICs/caps, etc. not trying to be harsh, just trying to open your eyes a little before you go gung ho on something that will blow your project up.
I guess I'll leave out the switch then
And when I said voltage regulator, I actually meant the whole system of components to achieve it. I understand about the bridge rectifier and the caps to remove the ripples. I know which pins to use for 12v, I did my research.
And just now I just learned that the bridge rectifier increases the DC voltage by ~1.41 times. Is this true? If so then I can just use a 12.6v transformer, use the bridge rectifier to make it ~17.8v, then use a 12v voltage regulator and have caps at the right places.
Here's my source:
http://diy-fever.com/index.php?project=power_box
I'm glad I'm asking you guys on this, thanks
Yes, when you rectify, your AC voltage of 12.6V then becomes about 17.8V because that is the RMS and that is what diode bridge does. If you go this route, then you don't need a super beefy heatsink, but it would still be wise to use one. You can still put in a switch if you want, what you would do is tap off your power supply before it gets to your 7812 and filter some more (since there is only one filter capacitor up to that point). That still gives you higher plate voltage, and your plate voltage doesn't have to be regulated, just rectified and filtered. I would highly recommend reading "Power supply basics" at geofex.com. Best resource on this stuff that I have found.
I'll go with the 12.6v transformer then. I got a heatsink that was originally bolted onto a voltage, and also got a 2x1 inch and 2.5x2 inch heatsinks. I'll check out geofex soon, thanks!
Here's the diagram for the twinkler if anyone is interested, just quickly drew it on microsoft paint:
(http://img80.imageshack.us/img80/5585/twinkler.jpg)
Many thanks to my friend who helped me with this circuit. He just wired his the input and ground directly the audio jack, so the circuit is working in parallel to the guitar signal (if I worded that correctly). Just wire the LEDs in series, parallel, or whatever and supply the correct voltage as usual. But since the LM386 opamp has some resistance, I think it'd be best to supply a little more voltage to achieve full brightness. So for a blue LED which has the typical voltage of 3.5v and 3.8v max, I would use 4v for each.
Hey folks,
It's been a month or 2 since I've contributed to this thread. I recently built a valvecaster for a friend of mine who loved my first invention (the tweaked valvecaster with an IC booster). I suggested that I build him one without the boost circuit, so it's a nice clean single-valve circuit. This time I put in a pot on both cathode resistors for gain just for fun to see what we can learn. Didn't learn much but it does sound pretty good. One thing I'm still dealing with is the change in tone between 2 identical tubes from different batches. I'm guessing I'll need to put in trim pots on the plates or grids for biasing but I have a lot of reading / comprehending to do before I mess around with that too much.
Anyway, here are the photos of it. It's basically a valvecaster running at 12 volts with 2 gain pots and a lower input cap. Oh, and I'm using an EH 12AY7 tube. This was a fun project. Oh, I gave it a small power indicator light for safety. A small but nice touch if I may say so myself! I'll build one for myself to use as a boost or to add some dirt to clean tones. My wiring has gotten cleaner but it's nothing compared to the super anal designs I'm seeing on this thread. You guys are amazing!
(http://homepage.mac.com/dshimmyo/musicForBlog/fire_hazard_II.jpg)
(http://homepage.mac.com/dshimmyo/musicForBlog/jtvcIMG_0085.JPG)
Hope you enjoy the pics!
Cheers,
Dan
That looks like a crazy bright LED. Looks good otherwise. Hope that tube doesn't get busted off up there...
Quote from: Ripthorn on August 20, 2009, 12:05:34 AM
That looks like a crazy bright LED. Looks good otherwise. Hope that tube doesn't get busted off up there...
Yeah, it is that bright too. The guy I built it for likes them super bright. Seems like a lot of people like them that way, me not so much, it's blinding... The tube mounted on top is kind of silly looking and not so practical but I like it. When I build something to take on the road I'm gonna have to design a bulletproof enclosure or buy an electro-harmonix chassis.
Been reading through this whole monster of a thread( taken 2 8hr shifts at work on and off to read) and would like to say i love all the versions of it. Im gonna have a go at building one of these myself just waiting on the tube and socket and my new soldering iron that ive been waiting for for a week. Have a nice wierd case hiding that i think will do the job nicely for what i have in mind.
I don't know if this question has already been asked but this thread is getting rather large to read from the beginning :), here goes:
I've been looking at the different brands of 12AU7 out there, especially on ebay. Some are rather expensive, other not. Is it really worth it to pay big money for such a tube? Is the difference in sound noticeable? Personally, I have tried Electro Harmonix and I'm satisfied but when I see those tube costing 80$ or more, I wonder what makes them so special.
I'd like to hear about your experience with trying different 12AU7 tube brands with this circuit.
cheers
A lot of those really expensive tubes are rare NOS tubes that have taken on an almost mythological status. Like old black plate RCA's or Telefunken's. Do they sound better? Depends on what you like to hear. Are they worth the money? How much do you have and how much does it matter to you? Personally, I like my old no-name tubes that I picked up for a couple bucks a piece.
In a low voltage stompbox application use whatever working 12AU7 you can get a hold of.
I got a bunch of Conn NOS 12AU7s a while back for really cheap. Tbh though, in a lowish voltage setting they aren't that much different than the modern production tubes.
hey again all,
so does anyone have a verified schem / vero for a TWINcaster? I got some nice Pre 1970's Philips EEC83's, and i was thinking they'd be tasty in a Twincaster running off either 12V or a voltage doubler and go for 18V (9V battery lol?!) First things first though, i need a verified schematic or layout.
Cheers,
tm
Have you tried the schematic earlier in this thread? It's basically just two cascaded valvecasters, but I don't see why it wouldn't work. I actually have one wired up, just haven't wire all the pots and put in the tubes yet. A more pressing matter popped up with a different project.
isildur100, I used a lot of different tubes, and yeah I found some differences amongst them...I definitely go with the old tubes, as they are cheaper than the new ones (lowest price paid=1€+1€ shipping from Germany!)
Go to EvilBay and you'll surely find some tubes at great prices...So great you'll be tempted to buy more than you need, just to try them out...
The ones I like the best are GE and Sylvania. The new EH I have doesn't sound so good to my ears...but that's ok...
Quote from: Renegadrian on August 23, 2009, 04:57:27 AM
isildur100, I used a lot of different tubes, and yeah I found some differences amongst them...I definitely go with the old tubes, as they are cheaper than the new ones (lowest price paid=1€+1€ shipping from Germany!)
Go to EvilBay and you'll surely find some tubes at great prices...So great you'll be tempted to buy more than you need, just to try them out...
The ones I like the best are GE and Sylvania. The new EH I have doesn't sound so good to my ears...but that's ok...
Hi Renegadrian! I will definitely try old ones as the only ones I've tried were new EH :) I have also bought some 12DW8 on ebay which are supposed to be 12U7 (not 12AU7) replacements but I was not impressed. Maybe I need to bias them differently... Anyways, the 12DW8 I bought are intended for a pepper shredder build. Can't wait to hear how they sound :)
cheers
hello everyone,
I am very new to building effects, in fact i have never built one in my life haha! I am very interested in building a Valvecaster to use as a bass drive. I have saved a few images from this thread so that i can use them for building a Valvecaster. Since i am a newbie, I was wondering if anyone has a list of parts that i would need to purchase to build this? Also, since i live in the US would http://www.smallbearelec.com (http://www.smallbearelec.com) be the best place to get everything i would need?
I would be most thankful to anyone who can give me advice/help with this as i am very excited to try this as my first project. Thanks in advance,
Cory
^ the first post has all the parts on the schematic. In addition to those parts, you'd need a mono jack, a tube socket, a stereo jack, a 3PDT, an LED, and an enclosure.
i rekon it doesn't sound too good on bass, there's too much compression for using it clean and not enough drive to get it sounding proper dirty. i'm gonna try modifying it for a more clean boost and run a fuzz circuit into it for distortion
I use it on bass too and am quite satisfied, it adds a good fatness...I like it so much...
I really like this thing on bass as well. I took the tone control out. Like Adrian said, it really fattens up the sound nicely! With the right eq settings on your amp, it also gives your tone a very "upright" sound.
I took the tone control out and my valvecaster doesn't work anymore... :P I'll have to find some time to troubleshoot what I did wrong when I removed it.
In order to get the toneless version you need the remove the pot (obviously) and C4 (10n) - So you have tube pin 6 connected to the 100k (to 12V) and to the volume pot lug 3 thru the C3 cap.
See all the schems/layout as reference. Hope it helps.
A.
Hello everyone,
I've read the entire post (70 pages must show my dedication) and finally built the no tone version of the valvecaster as per Renegadrian's vero layout.
The only part I've haven't got is the gain pot, shown as a B50k pot, I've only got B100K or B10K pots and for some strange reason trying get a Alpha B50K in the UK seems near impossible.
So my question is can I use the B100K pot?
Many thanks
Matt
Hi Everyone,
Finally finished two Valvies. Sounds great. I tried to ground everything to the back of one of the pots. I also used the 7812 voltage regulator. I found it is very important to use a good power supply to keep the pedal quiet. I have one question:
Has anyone had a problem with a noisy gain pot? Using new parts and on both pedals I can hear a scrape like a dirty sounding pot. Other than that I love the pedal.
Thanks for the help and the great design.
Quote from: mmaatt25 on August 27, 2009, 07:57:09 AM
The only part I've haven't got is the gain pot, shown as a B50k pot, I've only got B100K or B10K pots and for some strange reason trying get a Alpha B50K in the UK seems near impossible.
So my question is can I use the B100K pot?
I prefer a 100K gain pot - it will give you cleaner boost.
Quote from: Pigyboy on August 27, 2009, 08:02:13 AM
Hi Everyone,
Finally finished two Valvies. Sounds great. I tried to ground everything to the back of one of the pots. I also used the 7812 voltage regulator. I found it is very important to use a good power supply to keep the pedal quiet. I have one question:
Has anyone had a problem with a noisy gain pot? Using new parts and on both pedals I can hear a scrape like a dirty sounding pot. Other than that I love the pedal.
Thanks for the help and the great design.
Man, we want PICS!!! As for the pot scratching, it's not a "problem", it's a known feature of this kind of gain - you are working on the cathode, and a change with the pot brings some lil noise.
Hi All,
Ok, this is going to sound really bad. I can build a pedal but I cannot figure out how to post pictures up on the forum! Give me a few pointers on this and I will be glad to put up my pics.
Thanks
You can get a photobucket account and copy the link to the picture. Then in a post here, click the picture button and paste in the url for the picture.
Thanks for the photo upload info. I will give it a try now. Here are pics of the 2nd Valvey I have made. Not too special to look at for my first time out but it really does sound good. Last night was the first time using it live. Not only did it work great, everyone said, 'Wow, What is that!?' I am waiting for some stand offs to properly mount the board so as you can see for now I have it snuggled in on top of a piece of foam.
(http://s852.photobucket.com/albums/ab86/pigyboy_2009/)
(http://<a%20href="http://s852.photobucket.com/albums/ab86/pigyboy_2009/?action-view¤t=Greenpedal.jpg"%20target="_blank"><img%20src="http://i852.photobucket.com/albums/ab86/pigyboy_2009/Greenpedal.jpg"%20border="0"%20alt="Photobucket"></a>)
(http://[img]http://i852.photobucket.com/albums/ab86/pigyboy_2009/Greenpedal.jpg)[/img]
Ok, got the pictures figured out. Let me know what you think!
(http://i852.photobucket.com/albums/ab86/pigyboy_2009/Greenpedal.jpg)
(http://i852.photobucket.com/albums/ab86/pigyboy_2009/GreenPedalinside.jpg)
(http://i852.photobucket.com/albums/ab86/pigyboy_2009/IntGreenPedal.jpg)
(http://i852.photobucket.com/albums/ab86/pigyboy_2009/GreenPedalLED.jpg)
Hey I like that! THX for posting...Nice wiring there... :icon_wink:
Thanks Adriano,
The only wire I had on had was from some heavy old electrical cabling I found. Quite colorful! I notice I burned a few of them too. Going to try to simplify the layout a bit more next time. I think it is possible to eliminate 2 ground wires as the metal chassis itself links the input and output jacks to ground.
My friends from Germany, Mamasweed, and are here in Spain for some shows and the guitar player has used the Valvy for the last two shows and now he wants one. Using it live is the true testing ground and these little pedals really sound great.
Hi, i have recently finished a modded valvecaster, and it sounds great but my volume pot is acting like a gain pot.
see the thread here:
http://www.diystompboxes.com/smfforum/index.php?topic=78671.0 (http://www.diystompboxes.com/smfforum/index.php?topic=78671.0)
Have anybody else experienced this with the valvecaster??
Quote from: Stellan on September 05, 2009, 11:33:52 AM
Hi, i have recently finished a modded valvecaster, and it sounds great but my volume pot is acting like a gain pot.
see the thread here:
http://www.diystompboxes.com/smfforum/index.php?topic=78671.0 (http://www.diystompboxes.com/smfforum/index.php?topic=78671.0)
Have anybody else experienced this with the valvecaster??
Post up your voltages and we'll detect what's amiss.
Set the Gain, Tone and Volume to maximum. Hook up the black probe of your DMM to ground and use the red probe to take readings from each of the tube's 9 pins.
Here's mine, taken from my fully functional Valvecaster, my power supply is 12 volt:
Pin 1: 3.02v
Pin 2: -0.518v
Pin 3: 0.00v
Pin 4: 0.00v
Pin 5: 11.97v
Pin 6: 8.21v
Pin 7: -1.285v
Pin 8: 0.00v
Pin 9: 5.91v
Also, you have made some component changes - post what you have changed and any other modifications you have made to the circuit.
Hi again,
Voltages usin 12v powersupply:
pin 1: 3,14
pin 2: -0,35
pin 3: 0,09
pin 4: 0,00
pin 5: 12, 04
pin 6: 7,45
pin 7: -0,52
pin 8: 0,11
pin 9: 5,86
Moddifications: C1 and C2 are both 22nf, and i have no tonecontrol wired up yet, but I don't see how that should cause problems... I tried other values for the other components but went back to stock values to see if that changed the problem. Obviously it did not.
Hmm, your voltages look good to me. It should be working fine.
Do you still have a pot at the input? Is the gain control now standard?
Quote from: frequencycentral on September 05, 2009, 02:04:16 PM
Do you still have a pot at the input? Is the gain control now standard?
Thanks for the replys.
I took the gain pot out of the circuit and jumpered the cathode to ground. I also tried different values for the catode resistor, all with the same result.
I have checked all connections with the DMM and everything seems fine to me. Really frustrating, as this should be fairly easy. There must be something
that I am missing...
Quote from: Stellan on September 05, 2009, 04:10:41 PM
I took the gain pot out of the circuit and jumpered the cathode to ground.
With the cathode grounded the overdrive will be 'always on'. The lower the resistance between the cathode and ground, the more overdrive you will get. You have hardwired it for maximum overdrive. Put that gain pot between the cathode and ground, I prefer a value of 100K, as that way you can have cleaner boost than with 50K
Yeah, I'll do that as soon as I have got this volume issue sorted out. I hardwired it for max gain, so it would be easy to hear if the volume could be turned down without turning down the gain.
Hi,
Just finished a hybrid of the twincaster/pepper shredder. Sounds great but I am getting a bit too much sizzle as the note fades. Any idea where I should look?
Thanks
Sizzle?
Schematic?
I used the Pepper Shredder Schematic at
http://www.tube-town.net/diy/lov/lov02-peppershredder-eng.html
but substituted the 1MA gain for 50kB and the volume 50kA for a 100kA. When I used the 1M for the gain and the 50k for the volume I got real bad sizzle. I also changed C5 and C8 from 10K to 22K resistors and it seemed to smooth it out a bit.
I used the tone stack from the twincaster schematic on this thread. Basically a .01uf cap in series with a 100kA pot. I like the crunch of the sound but it does get a small sizzle sound if I let a note ring and fade. It is almost a clipping sound. I have a good power supply that works well with my other pedals so I do not think it is the problem. Thanks for the help.
Are you saying you took the pot for gain out of the pepper shredder and put in the variable cathode resistor gain control of the valvcaster? If you simply replaced the value of the pot, that isn't going to result in the best sound. If you did put the gain control on the cathode, did you remove the cathode resistor? Also, if you change the cathod bypass caps, you can control how much low end is let through. If you then put a resistor in series with that bypass cap, you can tame the high end gain and get (what I think) is a little smoother of a response.
Hi,
I used the pepper shredder schematic so the gain is between stage one and two of the first tube and not off the cathode, right?
Do you recommend I use the exact parts called for in the pepper shredder schematic? I have not heard the pepper shredder before this so I have nothing to judge the sound by and breadboarded it was very trebly. I am just learning about this stuff so thanks for bearing with me and my mistakes.
Tube preamps when used direct can sound insanely harsh and fizzy. If you are playing through a speaker, a lot of that will go away, though possibly not all of it. Also, having changed the gain pot, there will be less gain available, as the signal will bleed to ground earlier with a 50k pot than with a 1M pot. If you are needing to get rid of some highs, I would look at putting a resistor in series with cathode bypass cap, or put in a set low-pass filter at the output just before the volume pot to get rid of some of that. You can experiment with both or a either and find what works best for you. To start, maybe try a 1k5 resistor in series with the first cathode bypass cap and see what that does.
Thanks for the help. I will give it a try and post my results.
Hi you all,
I just joined this forum and I'm very glad to see that there are lots of people helping each other to save money with these gadgets.
I am going to build one of these boxes to my son for his guitar rig, but I wonder if I could modify it to make another one for my Hammond organ.
It's a T-200 solid state organ which I have modified heavily and it sounds pretty good with passive zener diode overdrive. I just would like to try if the tubes could add a little warmth to the sound. I've tried some regular overdrives inserted after the pre-amp (~600mV) but they won't sound good, there's too much noise.
I thought I could try this as it is first, but if someone has an opinion or a suggestion I will be more than happy :icon_smile:
Thanks,
Jussi from Finland
You won't be saving money in the long run, believe me, I have spent way more on this than I would have spent on pedals. Of course, I have a lot more pedals than I would have had. The only way to really answer your question is "try it out and see what happens". As for noise, you might not see a significant improvement over a solid state circuit.
Thanks for your answer.
I think I didn't make myself clear, sorry for my lousy English...
The question is: Can this effect handle line level input signals as it is, or do I have to change some components? And is the output level strong enough to match the line level input of the main amp, or does it need any modification?
I know that the problem with the ordinary pedals in this case is that in most guitar pedals there's a bass roll-of circuit to make the sound sharper, and that is not what I want. Also the output signal isn't usually strong enough without a buffer amp, and that's what causes the noise when using them with line level signals.
I guess I just have to build the guitar version first and try it with the organ. I was just hoping that someone would have had the same problem and already solved it...
Cheers,
Juha
Your question is all about headroom and amplification. When it comes to tubes, that translates directly into plate voltage (for the most part). So the answer to your question is "maybe." It really depends on your plate voltage. If you go 9V plate voltage, I highly doubt that it will work any better than any other pedal you have tried. If you put, say, 150V or higher on it, it could probably match your output level pretty well and give enough headroom that the clipping range is wide enough for good use. Of course, you will really need to play with the voltage to see what you need for your particular situation. I think a 12au7 can handle something like 300V or so on the plates, so try different plate voltages up to that range to see if you can get enough output. Just as a side note, on one project I did, I found that the difference in output level between 24V and 100V was ridiculous, it was so much louder it was hard to believe.
OK, Brian,
I think that with my skills I have to keep away from those high voltages and try to figure out something with transistors... :o
Thanks for the info,
Juha
Depending on what you want to do, you could use a high voltage opamp (by high voltage, I mean something like +/-24 or 30V) which could be done using a charge pump to get the right voltage from a +9V supply. Of course, those opamps start at 3 or 4 USD and go up to over 100 depending on what you want. The thing there is that the voltage swings can be huge, making line level inputs plus gain no problem. The only thing is that if you want overdrive, you will have to find a way to do natural clipping. Of course, you could always look at RG's adjusticator over at geofex.
So, I finally got a 12v supply for my Valvecaster yesterday. I was just playing through 9v batteries occasionally to play with it. This is a filtered and regulated power supply. It's a 12v 1Spot with a capacity of 1500ma.
Got it all set up and turned it on. I'm getting a hiss from the circuit now. I've tried putting a 22uf cap in to filter the power (it was the only one I had laying around) and it helped but i still enough hiss that it's annoying.
Also, the hiss is louder when I turn the gain pot down. Probably has something to do with the fact that the gain shorts to ground. I really can't turn the volume pot up more than half way without the hiss being unbearable.
Is there anything else simple I can do to filter the power? The power is the only thing I can think of that it would be since I haven't changed anything else.
Are your components rated high enough? I am guessing that they are. The only other way to really filter out a power supply is to either add caps to ground or inductors (or sometimes a resistor) in series. If the supply is already filtered and regulated, I don't suspect that it would need too much external filtering, if any. Have you audio probed with both 12 and 9V to see what the differences are at each stage in the circuit?
I took a look at my voltages and it looks like they may be off a bit judging by earlier posts. Also, it looks like the voltage on pin 6 is almost identical on both supplies. My output cap is a tantalum because it was the only one I could find around here in that value. Not sure if that could cause any problems. I'm 99.99% sure that I put it in with the correct polarity. I may swap it out for something else.
12v:
1: 5.82
2: -0.15
3: 0
4: 0
5: 12.13
6: 6.86
7: -0.16
8: 0
9: 6.11
9v:
1: 6.31
2: 0
3: 0
4: 0
5: 8.46
6: 6.85
7: 0
8: 0
9: 4.2
Lookiing at your 12v voltages, pin 1 is too high and pin 6 too low - check for dry joints or resistor values that are out?
Resistor values are good. Going to try resoldering those joints here after a while. My soldering skills leave a bit to be desired and it may be the problem. :icon_redface:
maybe you swapped the two resistors (pin1 220k - pin6 100k) ??
As the first plate res. has an higher value, it should receive less voltage than the second plate...If I am right?!
Edit: I didn't read you already checked them...mmm...
Update:
Re did the joints. the voltages went down a bit but not much. pin 1 is now 5.76 and pin 2 is 6.82
Well, the thread has dropped to page 5, so its time to get it back on the front page...
After more than a year i have have finally made the Valve Caster work. I started when 2008 was fairly new, but I couldn't make it work. I even rebuild it from scratch (twice) and tried three different tubes and and two power supplies in all combinations. In disgust and dispair I threw it in my box with abandoned circuits where it has been for more than a year.
Last week I pulled it out from the box, plugged it in, and it worked!!!!! I have heard about self-healing circuits, but I really don't have a clue why it suddenly worked.
One thing puzzles me, however: The voltages on the pins are pretty close to the ones frequencycentral posted on the last page, except for pin 1, which is almost twice the size. I have measured R2 and it is 220K as it should. Should I change the value of R2 in order to lower the voltage on pin 1?
Here's my voltages (FC's voltages in paranthesis for reference). I used Renegadrians no-tone vero-layout: http://www.aronnelson.com/gallery/main.php/v/Renegadrian/Valvecaster-no-tone.gif.html
Supply Voltage 12.03 regulated
Pin 1: 5.4v (3.02v)
Pin 2: -0.75v (-0.518v)
Pin 3: 0.00v (0.00v)
Pin 4: 0.00v (0.00v)
Pin 5: 12.03v (11.97v)
Pin 6: 7.46v (8.21v)
Pin 7: -1.20v (-1.285v)
Pin 8: 0.00v (0.00v)
Pin 9: 6.21v (5.91v)
Regards
Carsten
How was your Gain control set when you took your voltages? Mine was maxed, ie the cathode was grounded. IIR the voltage at the plate (anode, pin 1) reduces as you put more resistance between ground and the cathode.
Quote from: frequencycentral on September 26, 2009, 05:05:06 PM
How was your Gain control set when you took your voltages? Mine was maxed, ie the cathode was grounded. IIR the voltage at the plate (anode, pin 1) reduces as you put more resistance between ground and the cathode.
It was turned almost all the way up, I had read your note about that in an earlier post. However changing the tube did the trick. With another tube the voltage of pin 1 came below 4V.
The first tube (a Mazda, bought on ebay.uk for 19p) does not sound bad at all but distorts more (in a nice way), while the second (RCA) is much more mellow.
Thanks for your help
Regards
Carsten
Hi, as a new member here I`m glad I found this page cause the tube pedal looks awesome! I bought everything I needed to build it, but unfortunately it does not work!
My question is; on page 1 on this thread there is a handy schematic of the pedal. I used this one when I built it. I get no glow on the heaters, and how come pin 9 is not connected?? it runs the heaters right?? pin 9, 4 and 5?? I assume this pedal is for a standard 12AU7??
I really would appreciate if someone would answer me on this one, thanks Frank
OH, I noticed the hot tip on the input jack was touching ground! and I read up on the 12AU tube and it says you can connect pin 4 and 5 in series and leave pin 9 blank! interresting! I`ll try it out tomorrow!!
It did not work! damn!... anyone got any suggestions?
A new question, on the handy schematic on page 1, are the pots wieved from the back or front? kinda makes big difference either way look at it.
Hi there - the pots are always drawn as you see their back. It should work anyway I believe, even if you wire them au contraire...
The tube heaters receive the 12 V they need with the pins 4 and 5. 9 is left unconnected.
Can you post some pics?!
I wired them as they were wieved from the back. But I thought it was meant to run on 9V?? I`ll post some pics a littlebit later! Thanks for the reply!
As promised here are the pics! The box was i littlebit tiny but I managed to get it all in there!
I must add that I tested it now and there is glow in the fils! Haha they were so small I didn`t notice it earlier! but now I hear this powerful hum! Does anyone see an error in the pics? ;)
It had to be carbon comp resistors and orange dips!
(http://img70.imageshack.us/img70/5359/13526175.jpg) (http://img70.imageshack.us/i/13526175.jpg/) (http://img70.imageshack.us/img70/13526175.jpg/1/w1095.png) (http://g.imageshack.us/img70/13526175.jpg/1/)
(http://img70.imageshack.us/img70/8654/24393583.jpg) (http://img70.imageshack.us/i/24393583.jpg/) (http://img70.imageshack.us/img70/24393583.jpg/1/w1095.png) (http://g.imageshack.us/img70/24393583.jpg/1/)
there is a tube socket in there somewhere..
(http://img70.imageshack.us/img70/5176/10889393.jpg) (http://img70.imageshack.us/i/10889393.jpg/) (http://img70.imageshack.us/img70/10889393.jpg/1/w1095.png) (http://g.imageshack.us/img70/10889393.jpg/1/)
(http://img209.imageshack.us/img209/3411/47580520.jpg) (http://img209.imageshack.us/i/47580520.jpg/) (http://img209.imageshack.us/img209/47580520.jpg/1/w1095.png) (http://g.imageshack.us/img209/47580520.jpg/1/)
As you can see I left pin 9 blank and no the resistor is not touching it
(http://img39.imageshack.us/img39/7207/44358343.jpg) (http://img39.imageshack.us/i/44358343.jpg/) (http://img39.imageshack.us/img39/44358343.jpg/1/w1095.png) (http://g.imageshack.us/img39/44358343.jpg/1/)
(http://img209.imageshack.us/img209/3073/86505514.jpg) (http://img209.imageshack.us/i/86505514.jpg/) (http://img209.imageshack.us/img209/86505514.jpg/1/w1095.png) (http://g.imageshack.us/img209/86505514.jpg/1/)
Here you see the result! It`s nice and shiny!
(http://img205.imageshack.us/img205/2702/71991243.jpg) (http://img205.imageshack.us/i/71991243.jpg/) (http://img205.imageshack.us/img205/71991243.jpg/1/w1095.png) (http://g.imageshack.us/img205/71991243.jpg/1/)
(http://img18.imageshack.us/img18/5842/46713832.jpg) (http://img18.imageshack.us/i/46713832.jpg/) (http://img18.imageshack.us/img18/46713832.jpg/1/w1095.png) (http://g.imageshack.us/img18/46713832.jpg/1/)
And again, I appreciate any response! thanks!
INFO! Looking from underneath inside; the pot on the right hand is the tone control, and on the right hand is the gain control. The big one is the volume
You need to use a regulated DC power supply with adequate filtering.
hmm, I`m using a standard wall supply. 9V DC 450mA Does this sound ok? if not, got any tips for a better suited one?? thanks
How hard would it be to modify this to function as a headphone amp? Would I just basically add a 386 based amp after this circuit? Also, I love the condor type cab sims. Where would add a cab sim into this, or any other type of headphone amp.
yeey! I hooked the pedal up to a 9V battery and the hum is gone! seems like it`s the power supply that`s messed up! I found a 1.1A regulated 9V wall supply on ebay. Does that sound right??
As Some of us have experienced before, power from a wallwart has to be well filtered and regulated.
Also, try to get one running at 12V as it suits the circuit and the tube best
yeah, I`ve tried 5 diffenrent wall warts and every single one is different from the other.. let`s hope this 9V I found works, if not I`ll have to buy a buch of batteries in the meantime.
hm...
Just make sure the wall wart you buy is center negative (or rewire the DC jack). Last thing you want to do is fry something.
center negative??.. All the wall warts I have is center positive. Thought they all were so. Anyways I connected the battery in such way that the tip of the plug was positive, so I guess it works that was with batteries but not with wall warts. Thanks for the help. I painted it gold and will be posting pics in a couple days!
The polished chassis were all scratched up so I painted the entire thing gold.. Cool
Stamped some stuff on it too.. looks retro
(http://img18.imageshack.us/img18/6518/45973852.jpg) (http://img18.imageshack.us/i/45973852.jpg/) (http://img18.imageshack.us/img18/45973852.jpg/1/w821.png) (http://g.imageshack.us/img18/45973852.jpg/1/)
(http://img131.imageshack.us/img131/1971/37951815.jpg) (http://img131.imageshack.us/i/37951815.jpg/) (http://img131.imageshack.us/img131/37951815.jpg/1/w1095.png) (http://g.imageshack.us/img131/37951815.jpg/1/)
(http://img63.imageshack.us/img63/1645/28386896.jpg) (http://img63.imageshack.us/i/28386896.jpg/) (http://img63.imageshack.us/img63/28386896.jpg/1/w1095.png) (http://g.imageshack.us/img63/28386896.jpg/1/)
(http://img80.imageshack.us/img80/3415/69340826.jpg) (http://img80.imageshack.us/i/69340826.jpg/) (http://img80.imageshack.us/img80/69340826.jpg/1/w1095.png) (http://g.imageshack.us/img80/69340826.jpg/1/)
Good usage of a hot power tranny. That sencence sounded weird! :-S
(http://img207.imageshack.us/img207/1336/65424632.jpg) (http://img207.imageshack.us/i/65424632.jpg/) (http://img207.imageshack.us/img207/65424632.jpg/1/w1095.png) (http://g.imageshack.us/img207/65424632.jpg/1/)
hey guys, i have my valvecaster built and have been using it for awhile. i took it to a buddys place and it didnt work. brought it back home and it worked... turns out that it works connected in the beginning of my fx chain but doesnt work with just guitar to valvecaster to amp... why is this?
Sounds like a weird problem, but if it truly doesn't work when going straight into an amp that suggests a very high output impedance. This is odd, especially since many amps have a large input impdance. Will it not work with any amp or just the one? Also, I have found that a poorly wired pot can cause loading like nobody's business (something like this gave me a heck of a time in my submini tube amp a couple months ago). That's all I've got for right now.
ive tried it on two different amps now. when i flip the on switch i get a louder hum but no signal. works fine in the chain.
Quote from: REGNAD on October 19, 2009, 02:23:13 PM
ive tried it on two different amps now. when i flip the on switch i get a louder hum but no signal. works fine in the chain.
Time to post some voltages! You haven't missed out the output cap by any chance?
i'll dig up the schematic I used and post. where do you want these voltages measured?
Quote from: REGNAD on October 19, 2009, 02:59:33 PM
i'll dig up the schematic I used and post. where do you want these voltages measured?
Directly from all 9 pins of the tube. Also include the voltage of the power supply you're using.
question, do i take these voltages with the tube inserted or not inserted?
Quote from: REGNAD on October 19, 2009, 05:46:57 PM
question, do i take these voltages with the tube inserted or not inserted?
Inserted.
i just discovered two things. im using a plastic box and my power negative was not common with signal negative, not sure if thats a deal breaker..but, i also discovered a cold solder joint. when the tube was wiggled i got a signal to pass through the circuit. resoldered all the socket lugs and all is good now. the voltages below where taken before i resoldered, so they may be skewed...
voltages:
incoming connected----9.2
pins:
1-9.0 vdc
2-0 vdc
3-started out around 7 vdc and stabilized at 1.3 vdc
4-power negative
5-9.2 vdc
6-9.1 vdc
7-0 vdc
8-started out around 5 vdc and stabilized at 1.3 vdc
9-4.5 vdc
Took some shots today of the finished pedal..
(http://img11.imageshack.us/img11/3640/30574253.jpg) (http://img11.imageshack.us/i/30574253.jpg/) (http://img11.imageshack.us/img11/30574253.jpg/1/w1095.png) (http://g.imageshack.us/img11/30574253.jpg/1/)
(http://img36.imageshack.us/img36/7636/89966127.jpg) (http://img36.imageshack.us/i/89966127.jpg/) (http://img36.imageshack.us/img36/89966127.jpg/1/w1095.png) (http://g.imageshack.us/img36/89966127.jpg/1/)
(http://img11.imageshack.us/img11/2903/70639458.jpg) (http://img11.imageshack.us/i/70639458.jpg/) (http://img11.imageshack.us/img11/70639458.jpg/1/w1095.png) (http://g.imageshack.us/img11/70639458.jpg/1/)
oh yes, I repainted it cause the writing didnt work well with the clear.
I like it!!!
I`ve purchased a 9 pin footswitch and tried connected it as the "0.5" layout says, but nothing happends. not even any hum! how do I know which way to mount the 9 pin switch?? it`s all square and got no sign of indication what so ever!
this is the "0.5" version of the layout.. neat layout
(http://img21.imageshack.us/img21/3599/valvecasterv05qs5.jpg) (http://img21.imageshack.us/i/valvecasterv05qs5.jpg/) (http://img21.imageshack.us/img21/valvecasterv05qs5.jpg/1/w531.png) (http://g.imageshack.us/img21/valvecasterv05qs5.jpg/1/)
but i found this other image of someone here building it totally dfferent?? take a look at the wiring of the switch. Which one is correct??
(http://img33.imageshack.us/img33/1270/valvecasterinterir.jpg) (http://img33.imageshack.us/i/valvecasterinterir.jpg/) (http://img33.imageshack.us/img33/valvecasterinterir.jpg/1/w528.png) (http://g.imageshack.us/img33/valvecasterinterir.jpg/1/)
Well, you can wire a 3PDT in some different ways...
as you can see, THIS IS SIMILAR (http://home.centurytel.net/flanneldrawers/3PDT-wiring.jpg), while THIS ONE (http://fuzzcentral.ssguitar.com/faq/switchwiringpnp.gif) is different...
If you followed my layout, be sure that the pins go in a horizontal way...
THIS GAUSSMARKOV (http://gaussmarkov.net/images/1590B_SETUP_TRUEBYPASS.bmp) image should be clear enough...(note the wiring here is different, but yeah look at the pins' direction!)
edit: HERE'S (http://www.fulltone.com/images/3pdt_lg.jpg) what I tried to tell you...The way it is oriented the holes are in the up/down position...See?! Be sure the switch is in its correct orientation, and it MUST work!!!
(at least the switching...) - that layout is obviously VERIFIED, I built a couple with a 3PDT, then SWITCHED (sorry...stupid here...) to DPDT.
this is what i used...
(http://i360.photobucket.com/albums/oo41/regnad/Valvecasternylayoutmkabler.jpg)
quick response! thanks! I`ll give it a try one of these days and those layouts certainly helped!
It`s finally done!!! Thanks for superb help!!! I`ll give back some relaxing photos for you fellas to enjoy!
kinda messy but everything`s up and going!
(http://img406.imageshack.us/img406/2581/28148411.jpg) (http://img406.imageshack.us/i/28148411.jpg/) (http://img406.imageshack.us/img406/28148411.jpg/1/w1095.png) (http://g.imageshack.us/img406/28148411.jpg/1/)
I dodn`t want the standard red led which all pedals have so I went for a yellow one! I think it matches the gold.
(http://img406.imageshack.us/img406/1116/83170806.jpg) (http://img406.imageshack.us/i/83170806.jpg/) (http://img406.imageshack.us/img406/83170806.jpg/1/w1095.png) (http://g.imageshack.us/img406/83170806.jpg/1/)
this is with 8 sec exp
(http://img42.imageshack.us/img42/3051/42506481.jpg) (http://img42.imageshack.us/i/42506481.jpg/) (http://img42.imageshack.us/img42/42506481.jpg/1/w1095.png) (http://g.imageshack.us/img42/42506481.jpg/1/)
15 sec expo!
(http://img2.imageshack.us/img2/2847/39064393.jpg) (http://img2.imageshack.us/i/39064393.jpg/) (http://img2.imageshack.us/img2/39064393.jpg/1/w1095.png) (http://g.imageshack.us/img2/39064393.jpg/1/)
sweet!!
I've just attempted a Vavlecaster and unfortunately I'm having some problems. I just get a loud hum when it's turned on!
I'm using an unregulated 15VDC 200mA wall wart with a 7812 regulator and a 100uf cap across the DC jack. On the output of the 7812 I measure 11.67V when the tube is out of its socket and about 9.8V when it is connected (I say about because the voltages wavers). Is this as expected? I also notice that there is continuity between the output of the 7812 and ground when the tube is in its socket - this is to be expected though, right? as pins 4 & 5 have continuity in the 12AU7.
Here are the voltages I've measured on the tube socket (both with the tube in and with the tube out):
Tube In
7812 Pin 3: 9.90V - 10.03V
Socket:
Pin 1: 9.30V
Pin 2: -0.29V
Pin 3: 0.14V
Pin 4: 0.00V
Pin 5: 9.84V (this was in keeping the voltage at pin 3 of the 7812 at the time)
Pin 6: 9.40V
Pin 7: -0.34V
Pin 8: 0.00V
Pin 9: 5.03V
Tube out
7812 Pin 3: 11.64V
Socket:
Pin 1: 11.37V
Pin 2: 0.00V
Pin 3: 0.00V
Pin 4: 0.00V
Pin 5: 11.63V
Pin 6: 11.50V
Pin 7: 0.00V
Pin 8: 0.00V
Pin 9: 0.00V
Does anyone have any ideas? I only just noticed that the wall wart is 200mA - is this enough for the tube?
Voltages should be taken with the tube socketed. Here's mine, taken from my fully functional Valvecaster, with the Gain, Tone and Volume at maximum., my power supply is 12 volt:
Pin 1: 3.02v
Pin 2: -0.518v
Pin 3: 0.00v
Pin 4: 0.00v
Pin 5: 11.97v
Pin 6: 8.21v
Pin 7: -1.285v
Pin 8: 0.00v
Pin 9: 5.91v
You will note that your pin 1 voltage is way too high. Are you sure the associated resistor is teh correct value, and that there isn't a solder bridge?
Your 200ma wallwart is maybe not enough, as the 12AU7 heater requires 150ma alone. Additionally, both the plates require a small amount of current, and the 7812 will also require current. That's probably why the output of your 7812 isn't achieving 12 volts. An overworked wallwart will hum!
Thanks for the reply!
When I bought the wallwart from eBay I'm sure it was supposed to be a 500mA one which is why I was surprised when I noticed just now it says 200mA! How about this one from Maplin: http://maplin.co.uk/Module.aspx?ModuleNo=32746 (http://maplin.co.uk/Module.aspx?ModuleNo=32746) It's regulated so I could ditch the 7812 leaving a bit more room in the case. Do you think 500mA will be enough?
The resistor is dead on 220K and I can't see any solder joints - there's no continuity between pins 5 and 1 either. Hmmm... might have to come back to this one with fresh eyes in a couple of days.
Quote from: letterbeacon on October 31, 2009, 10:59:25 AM
How about this one from Maplin: http://maplin.co.uk/Module.aspx?ModuleNo=32746 (http://maplin.co.uk/Module.aspx?ModuleNo=32746) It's regulated so I could ditch the 7812 leaving a bit more room in the case. Do you think 500mA will be enough?
That's the one I use. Yes you can ditch the 7812 with that one, and (to answer your next question!) it will power both a Valvecaster and a Vintage Vibe at the same time.
I bought the wallwart from Maplin today so I've ditched the 7812 and now have a healthy 12VDC when the tube is in place. I still can't figure out why I'm getting such a high volt reading at pin 1 though. Even when I desolder the C2 (the capacitor that bridges pin 1 and 7) I'm reading around 10V at pin 1. The resistor is a .25w 1% 220K metal film resistor.
I'm also getting a higher than usual reading at pin 6. Again there is a resistor used here to drop the voltage but again it doesn't seem to be dropping it enough.
I'm a little stuck here!
R4 is the problem maybe? Definately 470K? And your tube is definately a 12AU7? Other 12**7 type tubes will give different voltages.
R4 measures to be 470K and the tube has ECC82 printed on it with ECC82/ 12AU7 printed on the box.
Here are the measurements at the pins with 12.10V coming from the DC jack:
Pin 1: 10.42V
Pin 2: -0.54V
Pin 3: 0.00V
Pin 4: 0.00V
Pin 5: 12:09V
Pin 6: 10.83V
Pin 7: -0.41V
Pin 8: 0.00V
Pin 9: 6.11V
I should add that the hum has gone away. The volume pot works but the gain control, when turned up, just makes it louder. I don't hear any distortion at all at the moment.
Hey guys, while i'm a bass player using a valvecaster on bass, just thought i'd clue you in on a little thing i learned tonight @ practice. Try inserting your valvecaster in your amp's effects loop, if it has one. I found mine adds a nice extra stage of saturation without getting muddy and ugly. Try it, you might like! I use a peavey Windsor and the valvy sounds awesome in the loop. I'm afraid to try the twincaster i made!!
200mA is not that much :-\
I got a 1A 9V regulated. It works absolutely perfect!! With 1A it gets lots of juice and breaks up smootly and powerful. recomended!
With 1A you can stay safe, 500mA are good too...
Quote from: runmikeyrun on November 04, 2009, 12:19:32 AM
Hey guys, while i'm a bass player using a valvecaster on bass, just thought i'd clue you in on a little thing i learned tonight @ practice. Try inserting your valvecaster in your amp's effects loop, if it has one. I found mine adds a nice extra stage of saturation without getting muddy and ugly. Try it, you might like! I use a peavey Windsor and the valvy sounds awesome in the loop. I'm afraid to try the twincaster i made!!
Would that just be from the line level of the fx loop?
I am new to this forum (and pedal building) and am really glad I found this site. I am hooked on building a valvecaster and want to get some parts on order. I was hoping to feedback on the best places to buy parts - I have been checking out this site, thetubestore.com and pedalparts.com. Also, as far as 12au7 tubes, I was looking at what thetubestore has and they range from $10 up. I was looking at the following and wonder if anyone has any thoughts as where to start:
NOS 5963 / 12AU7 The 5963 tube will replace 12AU7 tube types and is equivalent to the European ECC82 tube and can be used in any 12AU7 or ECC82 circuit. - $9.95
RFT ECC82Like all RFT preamp tubes, the RFT ECC82 / 12AU7 is a low noise and low microphonic preamp tube. It sounds great and is especially good for guitar amps because of its rugged construction. $29.95
I would appreciate any input anyone has
I would also like to know where to get the cool aluminum knobs like the ones in the pictures posted by tipetu recently
Smallbear electronics
- Chris M
thanks for pointing me to Small Bear Electronics - I sent off my order tonight.
Last thing to buy are a couple of tubes. I found some really cool vintage 12au7 tubes at audiotubes.com that I am considering ordering, but am a little confused about heater voltage and tube life. I've read many of the posts here and I can't quite figure out if I should use 12VDC or 9VDC
12V DC is what you need. Make sure it is regulated and filtered.
I haven't read all 75 pages of this, so i am wondering if anyone has build a TRIPLEcaster...? Or even a Quadcaster... I am considering it. I should run my valvy into my twincaster to see how it sounds.
Quote from: Wasted_Bassist on November 05, 2009, 07:25:31 PM
Quote from: runmikeyrun on November 04, 2009, 12:19:32 AM
Hey guys, while i'm a bass player using a valvecaster on bass, just thought i'd clue you in on a little thing i learned tonight @ practice. Try inserting your valvecaster in your amp's effects loop, if it has one. I found mine adds a nice extra stage of saturation without getting muddy and ugly. Try it, you might like! I use a peavey Windsor and the valvy sounds awesome in the loop. I'm afraid to try the twincaster i made!!
Would that just be from the line level of the fx loop?
yeah, my amp has a preamp control that drives the fx loop, so the more i crank the preamp the more signal gets to the valvy and the harder it's driven. if you have a preamp control (pre-gain, etc) you should have some control over it. Then you control how much signal is getting to the poweramp using the valvy's volume control. Just be sure not to overdrive the poweramp with it, the volume should be the same with the valvy on and off.
Well I built mine on a proto-board tonight. I found a tube at my electronics store but they didn't have a socket so I solder 8 wires right to the tube and harvested all the cap's out of dead components. Its running at 12v but getting a small hum and hiss, so I'm looking to get a 12v regulator tomorrow but I always like to salvage if possible. I have a small practice amp that I gutted for parts, and it has a small transformer in it but it outputs 12v AC, not DC. What is required to change AC to DC? Is it worth it? I just want to try and use whatever I have laying around that I can. lol. Also for pots, all I have a 100k B type pot, a 500k pot from a humbucker guitar and 250k pot from my strat and 10K-B pot from my practice amp. Which one would be best for the gain control?
I am building my first valvecaster using the schematic on page 1 by dano/beavisaudio.com and have a question about the placement of C3 & C4. The schematic shows C3 connected from pin 6 of the 12AU7 to to lug 3 of VR3 with C4 connected between lug 3 of VR3 and to lug 3 of VR2. However, according to the pcb-less wiring diagram also by dano/beavisaudio.com, C3 is connected from pin 6 of the 12AU7 to lug 3 of VR2 and also to lug 3 of VR3 and C4 is connected from lug 2 of VR2 to ground. I found one post that said "Lug 3 of tone pot in jumpered to lug3 of volume pot just because the author inverted the order of tone pot & cap, with no remarkable differences". I am interested in any feedback anyone may have on this.
^
^
Either way is fine, won't make any difference.
I'm still having problems with my Valvecaster. I have a feeling that it might be the tube. Can I confirm that when the tube is plugged in the 12VDC is shorted to ground?
Apologies, I can't seem to find the edit button for the previous post.
What I mean by the previous post is that when I insert the 12AU7 tube into the socket, my DMM says there's continuity between the 12VDC coming into the circuit and the ground. Is this normal?
I also don't understand why the voltage I measure at Pin 1 is so high (I read 10.42V). Isn't R2 responsible for the voltage down to around 3V? My R2 measures dead on 220K so I don't understand why the voltage at Pin 1 is so high!
If anyone can shed any light then I would really appreciate it!
Well, your DMM may just call the low resistance between pins 4 and 5 'continuity'. Like a light bulb, the heater doesn't have a lot of resistance. Try reading that with the ohmmeter and see if you get some low resistance.
I haven't built the Valvecaster, but have it on LT Spice as a simulation....I get close to 7V at the plate of V1, so you are probably in the ballpark. If you are reading w/no tube in the socket, don't forget that the tube's resistance (Rp) must also figure in when thinking about what the voltage there will be. Don't worry, you can't hurt it!!!!! It's rated for like 350V ;o) It all depends on Rp and the cathode resistance...
Quote from: GibsonGM on November 27, 2009, 10:28:24 PM
Well, your DMM may just call the low resistance between pins 4 and 5 'continuity'. Like a light bulb, the heater doesn't have a lot of resistance. Try reading that with the ohmmeter and see if you get some low resistance.
Yes you're right, I measure 11 ohms between pins 4 and 5.
Quote from: GibsonGM on November 27, 2009, 10:28:24 PM
I haven't built the Valvecaster, but have it on LT Spice as a simulation....I get close to 7V at the plate of V1, so you are probably in the ballpark. If you are reading w/no tube in the socket, don't forget that the tube's resistance (Rp) must also figure in when thinking about what the voltage there will be. Don't worry, you can't hurt it!!!!! It's rated for like 350V ;o) It all depends on Rp and the cathode resistance...
I don't seem to get any overdrive or distortion with my Valvecaster, it just acts like a boost and makes the signal slightly louder. This is my first tube project so I don't fully 100% understand the circuit -which components do you think I should be looking at?
I actually think you're only supposed to get the very Slightest overdrive from the circuit, if I am reading it correctly...the supply voltage doesn't seem high enough to push the 'AU7 into grid current limiting or cutoff, but to slightly 'round over' your signal. This would be great going into a tube amp - it would take the place of the input section, and then drive THAT harder (like a REAL TUBE SCREAMER, if you get the drift). Then the output from amplifier stage 1 is higher, and so on, leading to more distortion in the amp....cascading gain stages.
You basically have a 1V P-P signal going in from guitar, and you get out about 7V...not bad, a transistor can do this too but not as "warmly" as a tube. You are, I'm sure, getting SOME distortion and 2nd order harmonics from the tube, also. A transistor would add 3d, 5th harmonics, which are fuzzy and brittle. What do you need to look at - what is going on that you don't care for?
For more info on basic tube operation, check out http://www.freewebs.com/valvewizard/index.html
This guy, the Valve Wizard, IS a wizard. Read up on 'triode gain stage'. To see what's happening with your circuit, you'd need to plot a load line for the 'AU7 at that voltage (very low!) and check out what different anode resistors could do for you. Also, whether to add a bypass cap or not.....I bought the dude's book, it is AWESOME!! The supply is so low here, we're lucky to just be getting a boost out of it, which is what it really is!
PS - I did some math, and the 12AU7 running at this voltage and anode resistance gives a gain of about....18. With gain pot set to about 10 ohms. So, it will clip up to the supply voltage level as it sags - expect an output less than that, of course. This indicates maybe a little dirt there due to insufficient drive, but not 'distortion'. Maybe changing the 220k on V1 to 470k or so might improve gain, but I don't think so, it's running so that it barely even indicates being alive on the load line, ha ha!
A 2nd avenue would be to bypass the cathode gain pot with a capacitor...maybe 47nF or so; this will give you a little 'treble boost' and make it seem brighter/clipped more on the high end. Better described on the site I linked above. Let us know how you make out!
Thanks for the info - I'm definitely going to check out the Valve Wizard website.
I thought this circuit was a low voltage tube distortion pedal, not just a tube boost. This YouTube video of the pedal seems to have distortion in it and I used his layout to build mine: http://www.youtube.com/watch?v=3cMqYlhSQ8c (http://www.youtube.com/watch?v=3cMqYlhSQ8c). Maybe I've completely misunderstood this circuit completely!
yeah the youtube videos are misleading. i too built mine to those specs. definatly not an overdrive. more like a boost with very mild tube breakup. the videos are either putting a distortion pedal after the valvecaster or using the valvecaster to overdrive the input on the amp. im pretty happy with mine, i would have preferred more breakup but my butler tubedriver takes care of that...
Hi,
Just finished mine today after replacing a tube with o/c heater! Mine sounds just as GibsonGM and others describe - warms the signal up very nicely but no real distortion. There's bags of boost - my volume is less than half way, but gain is max. Driving mine with 12v - no hum issues. I'm very impressed with the sound from such a simple circuit. Warms up the front end of my solid state amp perfectly!
Dom
Cool, Dom. Definitely a good idea to run it at 12V if you have an extra supply or don't mind another power cord - you get that much more headroom.
A tube amp will break up a lot if you increase the input signal it's expecting to see from 1 or 2V from the pickups, to 7 or 8 from the Valvecaster. This can = a lot of gain at the front end, and totally overdrive your input!! Think of solos by Stevie Ray and others...
I turned the Gain all the way up and there is some overdrive there, so it does work after all! I've spent most of my day reading that Valve Wizard site - definitely going to pick up the book I think.
Are there any DIY tube distortion pedals around? I'd imagine they'd probably need a DIY power supply to go with them, but I don't mind building one of those as well.
Quote from: letterbeacon on November 29, 2009, 11:14:46 AM
I turned the Gain all the way up and there is some overdrive there, so it does work after all! I've spent most of my day reading that Valve Wizard site - definitely going to pick up the book I think.
Are there any DIY tube distortion pedals around? I'd imagine they'd probably need a DIY power supply to go with them, but I don't mind building one of those as well.
Are you looking for more gain?! Try my Tube Star!
http://www.diystompboxes.com/smfforum/index.php?topic=74888.msg610047#msg610047
Can't see the Tube Star schematic as the site is blocked by our server at work. I'll have to have a look at home.
The Valvecaster seems to have loads of clean boost, presumably as a result of the 2nd stage so there's plenty of oomph available (the obvious limiting factor running off 9 or 12v). I wonder if there's a simple way to drive the 1st stage harder and the 2nd stage not so hard to provide a bit more crunch but with less clean headroom? Would a 12A?7 valve with more gain spice things up?
Just ideas at the moment - I've asked santa for the Valve Wizard's book!
Dom
Quote from: Renegadrian on November 29, 2009, 06:28:17 PM
Quote from: letterbeacon on November 29, 2009, 11:14:46 AM
I turned the Gain all the way up and there is some overdrive there, so it does work after all! I've spent most of my day reading that Valve Wizard site - definitely going to pick up the book I think.
Are there any DIY tube distortion pedals around? I'd imagine they'd probably need a DIY power supply to go with them, but I don't mind building one of those as well.
Are you looking for more gain?! Try my Tube Star!
http://www.diystompboxes.com/smfforum/index.php?topic=74888.msg610047#msg610047
Hi! I thought about doubling your Tube Star circuit and use it as a high gain preamp.
I have two questions:
Where should i put the tonestack? Between the two stages (i mean between the two Tube Star circuit) or at the end of the circuit?
(i bypassed the tonestack in my amp, its like a Vibro Champ or Tweed Champ now)
Resistors are normal 1/4W resistors with 50V B+ or they should be more powerful at some places like the cathode resistors?
i tried a 12ax7 in mine and it sounded bad. much less volume. over all bleah...
editfail :icon_redface:
Instead of bulding a 12V power supply for the valvecaster or dual valvecaster, is there one you can buy with the right volts and amps ratings? i am only asking as i am not sure about building them.
Quote from: WhenBoredomPeaks on November 30, 2009, 08:31:45 AM
Hi! I thought about doubling your Tube Star circuit and use it as a high gain preamp.
I have two questions:
Where should i put the tonestack? Between the two stages (i mean between the two Tube Star circuit) or at the end of the circuit?
Resistors are normal 1/4W resistors with 50V B+ or they should be more powerful at some places like the cathode resistors?
Didn't try the double star, let me know if it turns out well!!! I'd put the TS as you say, between tube A and B.
It seems that 1/4 W res handle fine the voltage - it's not high enough to need other types!
-
REGNAD I tried an AX7 too, the result was awful.
Quote from: KH602 on November 30, 2009, 05:57:26 PM
Instead of bulding a 12V power supply for the valvecaster or dual valvecaster, is there one you can buy with the right volts and amps ratings? i am only asking as i am not sure about building them.
Any 12V power supply with at least 200 ma for the valvecaster or about 400 ma for the twincaster should be fine. It may require extra filtering if it isn't already filtered, but that is easy. Also, make sure to note the type (center positive or center negative) and wire accordingly (most stompboxes are center negative).
Quote from: Ripthorn on November 30, 2009, 09:42:51 PM
Quote from: KH602 on November 30, 2009, 05:57:26 PM
Instead of bulding a 12V power supply for the valvecaster or dual valvecaster, is there one you can buy with the right volts and amps ratings? i am only asking as i am not sure about building them.
Any 12V power supply with at least 200 ma for the valvecaster or about 400 ma for the twincaster should be fine. It may require extra filtering if it isn't already filtered, but that is easy. Also, make sure to note the type (center positive or center negative) and wire accordingly (most stompboxes are center negative).
does it matter how much current runs through it? eg. max current through valvecaster & dual valve?
big misunderstanding wih current. current is the flow of electrons, or electricity. a power supply is given a rating of lets say 12vdc at 500 milliamps. it delivers 12 volts and can dwlliver up to 500 milliamps. the load is only going to take what it needs. in other words, you could have a 12 volt 15 amp power supply and the load (the tube circuit) is only going to draw the amperage it needs, nothing more. hope that helps.
Hi,
I replaced the 12AU7 I had in my valvecaster for a 12AY7 in the quest for a little more gain/drive. There is definitely more gain/drive not as much as thought I would get bearing in mind it should be double the the gain according to the figures (12AU7 gain 20 & 12AY7 gain 45). What i did notice more was the volume drop using the 12AY7. Unity on my setup with 12AU7 was 9 oclock with gain at 12 oclock, but with 12AY7 unity was 12 oclock with gain the same at 12 oclock.
Has anyone else noticed this volume drop??
Many thanks
Matt
This volume drop is not an uncommon thing with tubes. This is what happens when tubes with different characteristics are put into the same circuit. IN order to take the biggest advantage of a higher gain tube, you have to change cathode and plate resistors, bypass caps, etc. Hope that helps.
Quote from: REGNAD on December 01, 2009, 03:07:31 PM
big misunderstanding wih current. current is the flow of electrons, or electricity. a power supply is given a rating of lets say 12vdc at 500 milliamps. it delivers 12 volts and can dwlliver up to 500 milliamps. the load is only going to take what it needs. in other words, you could have a 12 volt 15 amp power supply and the load (the tube circuit) is only going to draw the amperage it needs, nothing more. hope that helps.
Thanks very much. just wanting to confirm things thats all. I have a 12V 2A supply lying around thats all. I just got my tubes today for it. Is it possible to dual valve an 12AU7 & 12AX7 in the dual valve circuit on here?
cheers
12ax7's tend to sound nasty when used in starved plate mode. What are you trying to achieve? If you want more gain, go for a higher voltage.
Quote from: Ripthorn on December 02, 2009, 08:58:15 PM
12ax7's tend to sound nasty when used in starved plate mode. What are you trying to achieve? If you want more gain, go for a higher voltage.
what kind of high voltages you talking about? reading this forum, i thought higher than 12V would lower its life exspectancy, but then again thinking about high powered heads like peavey & marshall they would use a lot more than 12v. when i got my 12AU7 valve i didnt think it would be that small due to looking at the valves in amps etc.
You are thinking of the heater voltages, those are the same. THe plate voltages are what I am talking about and those govern how the tube reacts to an incoming signal when coupled with thing slike the plate and cathode resistors, etc.
I removed the gain pot (it's always maxed out) and the tone pot and cap (i don't use it). Seem to have just a smidgeon more gain and just starting to get some crunch. :)
Quote from: BigBadDom on December 04, 2009, 11:00:22 AM
I removed the gain pot (it's always maxed out) and the tone pot and cap (i don't use it). Seem to have just a smidgeon more gain and just starting to get some crunch. :)
It's not just you, you are getting more gain. That is because the cathode of the first stage is now completely grounded and there is not signal at the tone stage going to ground. I have a twincaster I'm working on, just need to pull it out and get it together.
So I just stumbled upon this thread which is extensive to say the least.
To sum up this is what I would like to do:
I'd like to build a tube boost using this technique (after reading up on en 12AU7 6111 Valve Caster Summary PDF):
http://www.beavisaudio.com/projects/ValveCaster/MatsuminValveCasterWiring.gif (http://www.beavisaudio.com/projects/ValveCaster/MatsuminValveCasterWiring.gif)
But using 12v (since most people seems to prefer it) and adding a 7812 and a 100uF filter cap on the dc jack to eliminate hiss.
Which components are preferred if I want a subtle and sweet overdrive sound?
I'm a bit new to all this, but I can follow a diagram...
Could someone please supply me with a BOM?
A revised wiring diagram (with the above mentioned additions) would be great as well...
Best,
Arlaharen
At page 69 you got a good layout!
Quote from: Arlaharen on December 04, 2009, 06:59:46 PM
So I just stumbled upon this thread which is extensive to say the least.
To sum up this is what I would like to do:
I'd like to build a tube boost using this technique (after reading up on en 12AU7 6111 Valve Caster Summary PDF):
http://www.beavisaudio.com/projects/ValveCaster/MatsuminValveCasterWiring.gif (http://www.beavisaudio.com/projects/ValveCaster/MatsuminValveCasterWiring.gif)
But using 12v (since most people seems to prefer it) and adding a 7812 and a 100uF filter cap on the dc jack to eliminate hiss.
Which components are preferred if I want a subtle and sweet overdrive sound?
I'm a bit new to all this, but I can follow a diagram...
Could someone please supply me with a BOM?
A revised wiring diagram (with the above mentioned additions) would be great as well...
Best,
Arlaharen
If you plan to use a 7812, you have to supply at least 14V, so you would likely need a 15V wall wart at the minimum. I think that tube selectionm will play a more ciritical roole in the result of this circuit than supporting components. I don't have a BOM or diagram, but perhaps someone can help you out with that.
QuoteAt page 69 you got a good layout!
You mean this http://www.diystompboxes.com/smfforum/index.php?topic=63479.msg645180#msg645180 (http://www.diystompboxes.com/smfforum/index.php?topic=63479.msg645180#msg645180)?
It seems that allt the images are gone in that post....
QuoteIf you plan to use a 7812, you have to supply at least 14V, so you would likely need a 15V wall wart at the minimum. I think that tube selectionm will play a more ciritical roole in the result of this circuit than supporting components. I don't have a BOM or diagram, but perhaps someone can help you out with that.
Ah, ok. Is there some other way to remove the hiss when using 12V?
Quote from: Arlaharen on December 05, 2009, 08:25:50 AM
QuoteAt page 69 you got a good layout!
You mean this http://www.diystompboxes.com/smfforum/index.php?topic=63479.msg645180#msg645180 (http://www.diystompboxes.com/smfforum/index.php?topic=63479.msg645180#msg645180)?
It seems that allt the images are gone in that post....
Hey, sorry guys - I don't know why the links had failed. So, here is a re-post for Mr Arlaharen! Thanks for your recommendation Renegadrian!Hey guys, here's my effort. First off, thanks to all those who have participated and provided great ideas on this thread! I am indebted to Matsumin, Beavis and all those who have followed.
OK, so my "Valve'd" has a few mods as you will see by the schematic below:
* The "Clarity" switch. As suggested by Krinor - refer http://www.diystompboxes.com/smfforum/index.php?topic=63479.msg518458#msg518458
* I added a power on/off switch and run the heaters at 12.6VDC & the plates at 24VDC using a customised power supply on my pedal board that has all sorts of outputs.
* The Gain Pot bypass for clarity at lower gain suggested by Ripdivot - refer http://www.diystompboxes.com/smfforum/index.php?topic=63479.msg516969#msg516969
* Various filter cap and plate resistor mods to vary gain and frequency range
I hope this helps some other people. I really enjoyed this project - especially the extra hardware for the enclosure. I also think running the pedal at the higher voltages helps the structure of the sound, but this thing will still run nicely at 9VDC on both power inputs - versatility is what makes this circuit so special! Extra thanks to Renegadrian, who seems to be keeping this whole thread together!
Excuse my Beavis-style schematic . . .
(http://macturkey101.googlepages.com/ValvedSchem.gif)
I went for the all polished chrome/stainless look and added a high intensity blue LED up the centre of the valve socket that lights up when the effect is on - mmmm, blue!
(http://macturkey101.googlepages.com/Valved3.jpg)
(http://macturkey101.googlepages.com/Valved4.jpg)
An nice old Mullard 12AU7 for that extra creamy goodness!
(http://macturkey101.googlepages.com/Valved2.jpg)
Obligatory gut-shot
(http://macturkey101.googlepages.com/Valved1.jpg)
And finally, the vero I used:
(http://macturkey101.googlepages.com/ValvedVero.png)
Cheers,
turkey101
Quote from: Arlaharen on December 05, 2009, 08:25:50 AM
QuoteAt page 69 you got a good layout!
You mean this http://www.diystompboxes.com/smfforum/index.php?topic=63479.msg645180#msg645180 (http://www.diystompboxes.com/smfforum/index.php?topic=63479.msg645180#msg645180)?
It seems that allt the images are gone in that post....
There's a good layout by member w437776 - it seems easy to build!
(http://i297.photobucket.com/albums/mm230/w437776/valvecaster.gif)
(http://i297.photobucket.com/albums/mm230/w437776/valvecasterpcb.gif)
Quote from: turkey101 on December 06, 2009, 01:02:29 AM
Quote from: Arlaharen on December 05, 2009, 08:25:50 AM
QuoteAt page 69 you got a good layout!
You mean this http://www.diystompboxes.com/smfforum/index.php?topic=63479.msg645180#msg645180 (http://www.diystompboxes.com/smfforum/index.php?topic=63479.msg645180#msg645180)?
It seems that allt the images are gone in that post....
Hey, sorry guys - I don't know why the links had failed. So, here is a re-post for Mr Arlaharen! Thanks for your recommendation Renegadrian!
Hey guys, here's my effort. First off, thanks to all those who have participated and provided great ideas on this thread! I am indebted to Matsumin, Beavis and all those who have followed.
OK, so my "Valve'd" has a few mods as you will see by the schematic below:
* The "Clarity" switch. As suggested by Krinor - refer http://www.diystompboxes.com/smfforum/index.php?topic=63479.msg518458#msg518458
* I added a power on/off switch and run the heaters at 12.6VDC & the plates at 24VDC using a customised power supply on my pedal board that has all sorts of outputs.
* The Gain Pot bypass for clarity at lower gain suggested by Ripdivot - refer http://www.diystompboxes.com/smfforum/index.php?topic=63479.msg516969#msg516969
* Various filter cap and plate resistor mods to vary gain and frequency range
I hope this helps some other people. I really enjoyed this project - especially the extra hardware for the enclosure. I also think running the pedal at the higher voltages helps the structure of the sound, but this thing will still run nicely at 9VDC on both power inputs - versatility is what makes this circuit so special! Extra thanks to Renegadrian, who seems to be keeping this whole thread together!
Thanks!
So if I want stick to your layout but only use one 12V input and skip the breadboard, how would the diagram look then?
(sorry about the basic questions, I'm fairly new at this and need to be baby talked)
Best,
Arlaharen
can i run the plates at 170V dc? ;D this seems like a good idea: http://www.ledsales.com.au/kits/nixie_supply.pdf
I never went that high, but yeah you can try for sure - also that PS has a trimmer to regulate the output voltage - I guess the plate resistors should be raised to 1W or something...but I'm no expert when talking high voltage (but yeah if we're talking AC/DC, the band I mean)
Quote from: w437776 on December 08, 2009, 04:48:02 PM
can i run the plates at 170V dc? ;D this seems like a good idea: http://www.ledsales.com.au/kits/nixie_supply.pdf
I've used that SMPS:
http://www.diystompboxes.com/smfforum/index.php?topic=78302.0
http://www.diystompboxes.com/smfforum/index.php?topic=74088.100
No need for 1W plate resistors!
uh ok Rick - good to know then!
so i can use this power supply without changing the valvecaster schematic?
Quote from: w437776 on December 10, 2009, 11:42:03 AM
so i can use this power supply without changing the valvecaster schematic?
I would guess so, but keep the volume control down when you try it, as you may find the output volume insanely huge. I've got that SMPS built onto a small piece of perf for experimentation, if I get the chance I'll hook it up to a Valvecaster over the holidays and report back.
I ran across this thread by accident a while back. then I found my registration for this site had lapsed a hundred years ago ...
Anyway, I have a couple of suggestions, based on mucking about with glass bottles for a long time. And all down to me being a cheapskate ...
Firstly, if a 12AU7 works, why not use a 6SN7? Very similar but octal base, and easy to find NOS versions cheaply. If you buy the Russki 6N8S versions on eBay, they are "cheap as chips". Look very impressive ...
Another valve that should work in the circuit is the ECC804 / 6GA8 which was designed for low noise - warning, different pin-out from the 12AU7 (pin-out like 6DJ8), 6.3V heaters only. You see them selling cheap, because nobody uses them in any modern design. They hit the market at the wrong time, when transistors were taking over, so they were never popular except in obsolete TV circuits.
A couple of other obscure types that might be useful -
5963 was for use in computers - sometimes they are great, sometimes they are noisy, they look like a possible alternative, and are usually cheap.
The Russian 6N6P is another possibility. Audiophiles get wet in the underpants about them, but they are hard to find, and you will be offered the 6N6P-I or 6N6P-VI most often - these are pulse mode valves, and are sometimes noisy.
I have not tried any of these ideas. Frankly, I don't have time right now - but I don't see a lot of harm in giving people my ideas. What's the point in having obscure knowledge if you don't share it occasionally? Anyway, I am pretty sure a 6SN7 will do the job, no messing, and a 12SN7 will do it too! Might as well use up those old things and stop them cluttering up a couple of nations ...
Welcome! 5963 - yeah I used one with good results!
thx for your suggestions...
i guess it should probably go here.
I'm working on a new design semi-based on this. Basically i've been looking at the transition/connection between triode and FET. I'd love to basically make 2 cascading fet/triode boosters running off the one 12AX7. The problem is, i can't seem to get levels of gain anywhere near the likes of simple fets like a j201 or a 2n7000 or a BC108. I'm trying to do this all (ambitiously) on 9 or 12V.
So, basically, what's the easiest way, on 9v, to get so much gain out of half a 12AX7 that it will produce overdrive like a FET would? I'm using this as a basic schematic by the way:
http://aikenamps.com/CommonCathode.htm (http://aikenamps.com/CommonCathode.htm)
Quote from: Renegadrian on February 19, 2008, 11:35:40 AM
Aren, thx for pointing out those errors, so here is version 0.5!!! (should be final...)
(http://img155.imageshack.us/img155/3599/valvecasterv05qs5.th.jpg) (http://img155.imageshack.us/my.php?image=valvecasterv05qs5.jpg)
Hey, post some pics of your version!!! I'll be glad to see them!!!
Sorry im a noob but... Where is the ground?
ground is usually on one of the jacks. Try to tie all ground wires there. Or to ease the wiring (less wires going to one point) solder some of those "to ground" points on the second track (there are 3 holes unused), and then run the wire on the left to the jack.
Guys,
Some of the drawings (e.g. the one shown in the post from Renegadrian on February 19, 2008, 10:35:40 AM), show that capacitor C4 is located between the ground (same ground connection that the volume pot is connected to) and the middle lug of the Tone pot.
However, the schematics that go around show that C4 is located between the tone pot and C3 (and the Volume pot).
Why is there a difference and what effect does this have on the unit? does this perform teh exact same function as teh schematics indicate? (I don't have that great electronics skills). If so, why wire it up differently than the schematics, if it does the same job anyway?
If it doesn't do teh same job, why are the schematics not drawn to reflect teh actual connection? (that one seems really odd to me...)
Another point is, the Tone pot and gain pot appear to have two lugs connected to ground on teh schematics, yet the connection diagrams that indicate teh components again do not seem to follow this principle. What's going on with this?
I'm hoping to start building my unit today, so I look forward to a speedy response.
Cheers guys!
Kryn
Welcome Kryn, glad you are going to build a Valvy!
I guess you meant this layout here --->LINK (http://img155.imageshack.us/img155/3599/valvecasterv05qs5.jpg)
Assuming this, and comparing it to the schem by Dano at the first page, let's explain how it works...
You see in Dano's that the signal leave C3 (it can be polaryzed or unpol.) to go to (pin 3 of) the volume. Just in between there is the tone cap and the pot controlling how much signal is going thru that cap to ground.
You also see Dano's PTP diagram here --->LINK (http://www.beavisaudio.com/Projects/ValveCaster/MatsuminValveCasterWiring.gif) He had C3 going to pin 3 of tone pot, but that way it worked counterclockwise, so using pin 1 fixed it. As you have surely read, it's verified by myself (my first one had the tone pot) and a lot of other people!
Hi, thx forthe quick reply! :)
Yes, I read it during lunch.
Now what I wonder is, should I use 9V or 12V when using the 12AU7's?
I can get a regulated 12V DC PSU, but not a 9V, in which case I wouldhave to cobble up a circuit to rgeulate that (I guess that would be easy if I just drop it to 9V with a voltage divider circuit and still use the PSU...)
77 pages are quite hard to read, but yeah we wrote several times that a 12V supply is better suited for that kind of tube!
I have now built 2 of these that sound identical. Both on 9v power supply. When I hook up 12v it hums loud. I cant tell if its regulated. Also..when I changed to a 12ax7 I noticed a hesitation when I hit a note hard. Anyone else notice this?
PS. Thanks Dano and Renegadrian for all the layouts. I have read most of the forum. Lots of mods and tips.
yeah, mine has a lot more hum when using 12V. I use 9V and a 12AU7. My impression is that the 12AX7 needs alot more power than the 12AU7, therefore the AU7 is more apropriate for this build. I`ll post some shots of the inside if anyone wants?
12AX7 needs higher voltages, I made some experiments at 50V but didn't get a decent sound out of it...
both the AU and the AT are good in the Valvy - dunno about the AY.
Pics are always appreciated!!!
I`ll open it up tomorrow and upload some.. btw, it`s not the most pretty one I tell ya that! but it works!
(http://img191.imageshack.us/img191/6551/img0516j.jpg) (http://img191.imageshack.us/i/img0516j.jpg/) (http://img191.imageshack.us/img191/img0516j.jpg/1/w640.png) (http://g.imageshack.us/img191/img0516j.jpg/1/)
(http://img690.imageshack.us/img690/6194/img0517w.jpg) (http://img690.imageshack.us/i/img0517w.jpg/) (http://img690.imageshack.us/img690/img0517w.jpg/1/w640.png) (http://g.imageshack.us/img690/img0517w.jpg/1/)
(http://img12.imageshack.us/img12/1834/img0518h.jpg) (http://img12.imageshack.us/i/img0518h.jpg/) (http://img12.imageshack.us/img12/img0518h.jpg/1/w640.png) (http://g.imageshack.us/img12/img0518h.jpg/1/)
(http://img204.imageshack.us/img204/890/img0519ox.jpg) (http://img204.imageshack.us/i/img0519ox.jpg/) (http://img204.imageshack.us/img204/img0519ox.jpg/1/w640.png) (http://g.imageshack.us/img204/img0519ox.jpg/1/)
That black tape in the middle of the tube socket is just to isolate the yellow led
Today I tried the pedal on my transistor marshall for the first time and there were actually NO HUM! I`ve been using this pedal on three other amps in which 2 of them are tube amps and the last one is a Crate transistor. All of them gave hum, but not the marshall. Strange... What amps do you guys run this pedal through?
i have mine in a chain feading an epi valve jr stack and the wet output of my mistress into a SS amp. all very quiet!
guitar>cs-3>fuzz>valvecaster>bk tube driver>big muff>carbon copy>mistress>SS amp
>boss eg>valve jr
I remember when this thread was under 10 pages... who knew it would become such an epic!
I just pulled a 12AU7 from a cheap old multimeter that was headed for the trash heap, so I decided to try this. I guess I'm a little late to the party. Sounds pretty good though!
You are never late to join the tube club...I am sure yours is going to be a great pedal!!!
I wired up a tube socket-to-breadboard adapter and have been going mod crazy and swapping tubes to see what all the fuss is about. A couple interesting notes:
I tried a couple RCA 5963 tubes and was very surprised to see them working with a plate voltage of less than 5V. I think I dropped the plate voltage all the way down to 3.8V and was getting some dirty boost and gain. I had no idea tubes could work at such low voltages.
Also, I made each section into a SRPP stage with first MOSFETs and later BJTs as the "upper" section. I also replaced the cathode resistance with JFET constant current sources. None of this made a huge effect on the sound. ::)
I just finished my valvecaster today. I ran into some problems with it not working and spent a few hours searching for what could be wrong.
I used an old input jack from a strat copy I had and didnt look carefully enough and wired the input connections backward :icon_lol:. I also used caps that were not 47nF but much smaller, after fixing these two problems it finally works! But if I turn the volume up past a quarter or so there is a loud constant humming sound, so some more work needs to be done, Im only on page 20 of this 80 page thread. I want to read through the whole thing before I decide what to do next, maybe Ill find a few mods to do :icon_lol: .
It sounds Amazing! Especially with the Valve Junior tube amp that I also picked up today. Really fat sounds coming from my Epiphone Les Paul Standard. Its a bit late tonight, but tomorrow I will make a demo video/mp3 file.
Here is pic of it:
(http://farm3.static.flickr.com/2756/4270877414_6aaa9f3ae5_o.jpg)
I will end up painting it once Ive read everything and make it work properly.
It's been a while since I managed to finish my valvecaster/sparkle boost pedal and it's really nice, gives a really smooth overdrive. I'm using it on bass and recently I've upgraded to a Markbass amp. It's a lovely amp, but it's very trebly and while I've managed to reign it in for my clean tone, when I step on my valvecaster I can hear a noticeable loss in the low end. Does anyone know how I could make it a bit more bass responsive? I've heard something about changing the input and output caps, but I'm not sure what sort of values I should be looking at.
Cheers!
Sorry if this has already been covered, but has anyone tried making a stereo preamp like for an ipod or something, with two 12au7's? One for each channel. maybe something like thepedal-sized zvex stereo tube amp. Any suggestion for keeping the signal ultra clean and is Hi-FI quality possible when opperating at this low of a voltage? if this is an old idea please direct me to where it was discussed, ...I cant find it?
thanks
In general, you won't get anywhere near hi-fi with this kind of a setup. The higher the voltage, the higher the clean headroom for a given circuit topology. There may be exceptions, but I am not aware of any off the top of my head. If you want something hi-fi, you should go the the musicelectronics forum and look at the tube hi-fi systems in the hi-fi section. Something like the valvecaster was not designed for pristine reproduction of the input signal.
A mod:
(http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=41939&g2_serialNumber=1)
Besides the output buffer and changes to part values, this basically shows an different way of doing a gain control on the Valvecaster. By moving a few connections around (not adding or subtracting any parts) you get a totally different gain control. To the left of the wiper it's essentially the stock gain control. To the right, it also acts as a variable load on V1 and a variable input impedance control for V2.
I encourage you to try this mod while you're building your next Valvecaster. If you don't like it, simply short the rightmost lug (in my schematic) to ground to restore the stock Valvecaster configuration. With stock Valvecaster values, this mod should provide more bass at high gain settings, as well as slightly more maximum gain.
Looks good your input grid on the second triode looks a bit small though.
Quote from: kurtlives on January 17, 2010, 11:05:56 AM
Looks good your input grid on the second triode looks a bit small though.
That's correct. It was mostly intentional. Such a low value makes a low impedance load on the plate of the first triode, so the first triode is attenuated more as the gain is turned down. Basically it makes the gain control have a better "feel" at the cost of lower maximum gain.
I tweaked a little more and stopped here:
(http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=41966&g2_serialNumber=1)
Wow, what a post....I think I quit at 15 pages though and skipped to the last 3 lol.
I think it's time to play with this, first with the original circuit....whew!
Hi all,
I just started looking at this thread a couple days ago, and I found this diagram. Is this an proper/accurate diagram for the standard valvemaster with a stomp switch, etc? (You know, without any mods?) Thanks so much!
Quote from: REGNAD on October 21, 2009, 09:47:11 PM
this is what i used...
(http://i360.photobucket.com/albums/oo41/regnad/Valvecasternylayoutmkabler.jpg)
Quote from: jrmcgrath13 on January 22, 2010, 02:14:22 PM
Hi all,
I just started looking at this thread a couple days ago, and I found this diagram. Is this an proper/accurate diagram for the standard valvemaster with a stomp switch, etc? (You know, without any mods?) Thanks so much!
Yea, that layout was the one I used and it works beautifully. Almost have my first build completed, except I need to replace the stomp-switch since I borrowed this one from another pedal and it's got issues...but otherwise the pedal works great. Had some hum from a dirty power supply initally, but made a separate in-line voltage regulator/filter following earlier instructions (on page 18 of this thread). After I replace the switch with a more heavy-duty one, I can then trade it to my coworker who wanted this...and start on the next build. I am thinking of going with a two-stage pedal next, feeding one Valvy into another in one chassis like others on this site have done (also including the regulator/filter internally).
As for what I named it? I just picked a name that was just too appropriate for a 12AU7 running cold ;)
Here are some pics:
(http://img685.imageshack.us/img685/3327/dscn0459z.jpg)
(http://img42.imageshack.us/img42/5929/dscn0461p.jpg)
Ok, Probably been said on here but....I lowered the input cap to .002 uf on my first valvecaster and ran it into a second one stock. Holy cool tube crunch. If you are looking for more gain...quit...just buy another tube and socket and build a second one. Put in the dpdt mini toggle and put stock input cap on one side and .002 uf on the other. You will not be disapointed. I left them in different boxes because I use one all the time for my "clean" tone and the other one is an insert on my vox tone lab. It turns on and off as I switch patches giving me distortion or not etc. Just though I would share. Both are running at 9v from a onespot wallwart.
Hi, I've been watching for quite some time, got round to building my first Valvecater over the festive season and though I'd share my findings..
My build is the standard single valve circuit running a Phillips (mil) 12 AU7. The only mod I made was to incorporate a simple audio relay in order to switch the on/off LED as I didn't have the correct footswitch. This made no difference to the sound. I run it at 10.6 volts
I tested it on 2 amps:
Mesa Boogie DC5 - On the clean channel there is a lot of extra gain and some overdrive but nothing to write home about. my Vox Valvetone pedal does a better job. On the dirty channel, there is a little extra drive but really this amp does not like this pedal too much.
70's Roost Sessionmaster. (50w) OMG!!! Running the amp at 8 pre & whatever the family will stand on the master, with the Valvetone flat out on all controls, there is a HUGE boost in volume. More importantly, the overdrive is wonderful, wonderful, wonderful. The amazing thing is the sensitivity to pick attack. Played gently - round smooth clean tones. dig in and the overdrive is simple amazing. no need to adjust the guitar volume (though it works as you would expect) just do everything with your hands. I'm obviously overdriving the preamp which is in turn overdriving the power amp so ? cascading gain? whatever -I love it. Compared to the Vox pedal which i've always liked, there is less overdrive but the sound is just so much more open
It also responds very well to the vox pedal being placed before it - boosting the gain further but not really changing the sounds so now I'll put a 2 valve version together. I'm keeping the current pedal intact as I don't want to change it and building from scratch will allow me to redesign the box as the current one suffers from bad placement of the in/out sockets when on a pedalboard. The cables look messy
Final point is re the AU7 / AX7 thing. I tried it with a newish AX7 and as expected, the sound was not great however, an old Brimar AX7 sounds very similar to the AU7 when used with the Roost. It didn't work well with the boogie.
Here's a pic of the finished article - no innards - started off neat then got worse and worse - think spaghetti and goliath welding and you'll be about there.
Sorry about the logo - my workmate's idea of a bit of fun but I've left it on
A HUGE thankyou to everone who has had a hand in this - I've really enjoyed building this thing
Regards
Kevin
(http://www.stallibrass.com/sharepix/VA-1.jpg)
I LIKE THE WAY IT LOOKS!!! :icon_wink:
Cool looking box, just don't try to sell it. :icon_biggrin:
One question - is it possible to run valvecaster or similar 12au7 tube based overdrive on 18V? are there any necesary modifications? I am asking because I don't want to stick a regulator in the enclousure and I already have an 18V power supply.
The plate voltage can go way beyond +18V safely, but NEVER exceed the heater voltage rating. For a 12au7 it's 12.6V in series, or 6.3V in parallel.
Hi guys ive been trying to build a tube stompbox for a week and none of them seems to work. i've tried to build GGG Tube Driver and failed, switch to Marsha Valve Tube also failed, and then yesterday i build Valvecaster..also failed. im using NOS Hitachi 12ax7 from the 80's. i know this tube isn't sound good in valvecaster setup, but i build it just to test the tube and valvecaster had the simplest schematic. i'm sure every cables and connection goes where it should but still the circuit produce no sound at all. im using 12VDC 1200ma power adapter by the way.
So whats happened with my setup?is it the tube malfunctioning?ive read few articles about how to powering the tube heater and a little confused because some mentioned that the 12ax7 work at best when the heaters are wired parallel at 6.3v instead of 12.6v series, while other articles and talk in this forum mentioned no problems wired it either way?im wiring my tube in series with pin 4 goes to 12vdc and pin 5 to ground.
If i want to wired the heater in parallel 6.3v do i need to create a R/C voltage divider?and if i do need the divider whats the value for the divider resistor and capacitor?thanks!
cheers.. :icon_biggrin:
So I yust have to use a proppriete resistor values to ensure those voltages to heaters and everything is going ok? How about the power? 1/4 W resistors are propably not acceptable? i shoulg go for higher ratings?
(http://www.failfunnies.com/images/2/you-have-failed-please-die.jpg)
ok jokin...as for the tube, I tried an AX7 and it sounded really bad, but the sound came out...It's strange you got no sound at all...Does the tube light up!? Maybe you count the pins in the wrong direction?! (I know it's a stupid point, but it happens, sometimes the easiest things give trouble...) - Check your tube pins and see if the heathers give some light...
And yeah the tube should work fine with the adapter you have and the wiring you wrote...
The first time I wired up a tube (a few weeks ago!) I got the pinout upside-down... and I have been doing this long enough that I should know better! Double check everything, and make sure the connections really are what you think they are.
Hi i double check it and i think im wiring it the way it should, because i can see clearly through the glass that the 4th & 5th pin are the heater and the 9th pin is the heater center tap?and no the heaters are not light up, but the tube glass get warmer.
And to test the circuit (the marsha valve) i replaced the tube with two 2sk30 JFET,change the first stage plate resistor for a 100k trim, tweak the trimmer a little and there is a sound!now im really, really, reallly confused ??? :icon_question: ??? what the tube is going on here? ;D
I must have done something wrong with the tube but i,..i, i just.. dang my head hurts! :icon_mrgreen:
Now i summon the Tube God to come down and shed some light on this! :icon_mrgreen:
...meanwhile i think i'll tweak the 2sk30 "Marsha FET" instead ;D
cheers!
I've found that preamp tubes glow way less when the heaters are powered by DC. I've got a box of random tubes that I've been messing around with on the breadboard and with some of them I can only see a pair of tiny orange dots at the top if I turn the lights out! I know they all work from testing them in an amp head (AC heaters). The glass getting warm is the sign that you need, I guess tubes aren't designed to always give an impressive display!
I've also found that not all 12AX7s guarantee an output with the 12V plate voltage. I've got a Fender tube that gives no output, JJs and EH that give a very weak output and the strongest comes from a couple of Chinese no-name tubes (one pulled from an old Marshall Valvestate). They still sound really thin compared to my Philips 12AU7, which gives the highest output of all.
Quote from: dukie on January 29, 2010, 04:14:56 AM
If i want to wired the heater in parallel 6.3v do i need to create a R/C voltage divider?and if i do need the divider whats the value for the divider resistor and capacitor?thanks!
A voltage divider won't work. Trust me on this. Running the heater at 6.3v is a little wasteful as it will consume twice as much power as running it at 12v (300m vs 150ma). Bit if you really want to run it at 6.3v, connect pins 4 and 5 to ground and feed 6.3v into pin 9. You can derive 6.3v (or 6v, which is close enough) in a number of ways:
- use a 7806 voltage regulator
- use a 7805 voltage regulator with two 1n4148 between the 7805's pin 2 and ground
- use a LM317 and associated components, as in the Subcaster
- use a voltage drop resistor in series with the heater. This effectively forms a voltage divider, as the heater is a resistor itself. The ohmage/wattage of the voltage drop resistor will depend in what power supply you plan to use with it. An 18 ohm 2 watt resistor for a 12 volt supply, or a 10 ohm 1 watt resistor for a 9 volt supply.
Quote from: anchovie on January 30, 2010, 08:03:09 AM
I've found that preamp tubes glow way less when the heaters are powered by DC. I've got a box of random tubes that I've been messing around with on the breadboard and with some of them I can only see a pair of tiny orange dots at the top if I turn the lights out! I know they all work from testing them in an amp head (AC heaters). The glass getting warm is the sign that you need, I guess tubes aren't designed to always give an impressive display!
I've also found that not all 12AX7s guarantee an output with the 12V plate voltage. I've got a Fender tube that gives no output, JJs and EH that give a very weak output and the strongest comes from a couple of Chinese no-name tubes (one pulled from an old Marshall Valvestate). They still sound really thin compared to my Philips 12AU7, which gives the highest output of all.
Yeah tubes aren't light bulbs! but yeah they should display some kind of heating, as they are heaters THAT'S THEIR JOB!!! :icon_twisted:
Quote from: anchovie on January 30, 2010, 08:03:09 AM
I've found that preamp tubes glow way less when the heaters are powered by DC. I've got a box of random tubes that I've been messing around with on the breadboard and with some of them I can only see a pair of tiny orange dots at the top if I turn the lights out! I know they all work from testing them in an amp head (AC heaters). The glass getting warm is the sign that you need, I guess tubes aren't designed to always give an impressive display!
Hi Anchovie i think you had unfinished sentence here..so what do i need, more voltage?if it is then what voltage that is adequate to heat this tube?18v,24v?because if 18v or 24v is enough then i'll build a voltage doubler circuit to heat it. Anyway when i switch the effect on with the tube running on 12v the other effect that use the same daisy chains power dimmed for a about 30 second or so before back to normal but their leds are not as bright as before the valvecaster is on. :icon_question:
Quote from: frequencycentral on January 30, 2010, 08:08:40 AM
Quote from: dukie on January 29, 2010, 04:14:56 AM
If i want to wired the heater in parallel 6.3v do i need to create a R/C voltage divider?and if i do need the divider whats the value for the divider resistor and capacitor?thanks!
A voltage divider won't work. Trust me on this. Running the heater at 6.3v is a little wasteful as it will consume twice as much power as running it at 12v (300m vs 150ma). Bit if you really want to run it at 6.3v, connect pins 4 and 5 to ground and feed 6.3v into pin 9. You can derive 6.3v (or 6v, which is close enough) in a number of ways:
- use a 7806 voltage regulator
- use a 7805 voltage regulator with two 1n4148 between the 7805's pin 2 and ground
- use a LM317 and associated components, as in the Subcaster
- use a voltage drop resistor in series with the heater. This effectively forms a voltage divider, as the heater is a resistor itself. The ohmage/wattage of the voltage drop resistor will depend in what power supply you plan to use with it. An 18 ohm 2 watt resistor for a 12 volt supply, or a 10 ohm 1 watt resistor for a 9 volt supply.
Yeah the 6v voltage divider is not working, i just tried it and the tube is not even warm.tried the 9 volt supply with 10 Ohm 1 watt trick too but the tube is dead cold.
cheers!
Hi dukie, I meant that warm glass is the sign that you need to confirm that the heaters are working! Don't go over 12.6V for 12A*7 heaters in series, that's what they're designed to use and too much will kill them.
The LEDs dimming on your other effects in the daisy chain suggests that the current draw is more than your PSU can put out. What are its specs?
Quote from: anchovie on January 30, 2010, 12:40:59 PM
Hi dukie, I meant that warm glass is the sign that you need to confirm that the heaters are working! Don't go over 12.6V for 12A*7 heaters in series, that's what they're designed to use and too much will kill them.
The LEDs dimming on your other effects in the daisy chain suggests that the current draw is more than your PSU can put out. What are its specs?
Hi Anchovie, my PSU is an unregulated 12vdc 1200ma (14.5Va Max) with variable voltage (1.5v-12v) and polarity selector that i modified with Dano's Hum Filter circuit.
What PSU spec that is needed to properly heat 12ax7 tubes?I mean the valvecaster can run on 9v DC and aside form 12ax7 bad sound, some people here reported no problem using it?
You said earlier that not all 12ax7 can output sound, so is it possible that i got this kind of tubes?
Maybe i should buy 12Au7 and throw this "no output 12ax7 tubes" out.. ;D
But im still curious.. ;)
Cheers!
Quote from: frequencycentral on January 30, 2010, 08:08:40 AM
Running the heater at 6.3v is a little wasteful as it will consume twice as much power as running it at 12v (300m vs 150ma).
Power dissipation of the heaters is determined by P=IV, so
P=(6.3V)(0.300A)=1.89W
or
P=(12.6V)(0.150A)=1.89W
But this is assuming you already have either a 12.6V supply, or a 6.3V supply. Dropping a 12V supply down to 6V, with a regulator, resistor, diodes, or
anything, will consume additional power.
Quote from: frequencycentral on January 30, 2010, 08:08:40 AM
Quote from: dukie on January 29, 2010, 04:14:56 AM
If i want to wired the heater in parallel 6.3v do i need to create a R/C voltage divider?and if i do need the divider whats the value for the divider resistor and capacitor?thanks!
A voltage divider won't work. Trust me on this. Running the heater at 6.3v is a little wasteful as it will consume twice as much power as running it at 12v (300m vs 150ma). Bit if you really want to run it at 6.3v, connect pins 4 and 5 to ground and feed 6.3v into pin 9. You can derive 6.3v (or 6v, which is close enough) in a number of ways:
- use a 7806 voltage regulator
- use a 7805 voltage regulator with two 1n4148 between the 7805's pin 2 and ground
- use a LM317 and associated components, as in the Subcaster
- use a voltage drop resistor in series with the heater. This effectively forms a voltage divider, as the heater is a resistor itself. The ohmage/wattage of the voltage drop resistor will depend in what power supply you plan to use with it. An 18 ohm 2 watt resistor for a 12 volt supply, or a 10 ohm 1 watt resistor for a 9 volt supply.
Hey, frequencycentral, will voltage divider work for valvecaster / twincaster type OD pedal, that will run on 18V? The divider is for heaters in series... I want to do this because I don't have any 7806 regulators...
Hey!
I have a question. You were saying that rising the voltage will make theese things sound better.
Well, I built PepperShredder
With this schematic (http://www.tube-town.net/diy/lov/lov02-peppershredder.jpg)
And I was thinking about feeding it with 24V. How will it work?
Quote from: ca cat on January 31, 2010, 05:14:09 AM
Hey, frequencycentral, will voltage divider work for valvecaster / twincaster type OD pedal, that will run on 18V? The divider is for heaters in series... I want to do this because I don't have any 7806 regulators...
To run a 12AU7 heater from 18 volts: pin 4 to ground, pin 5 to 18 volts via a 36 ohm / 1 watt resistor. You should be able to measure around 12.6 volts at pin 5.
Quote from: served on January 31, 2010, 07:27:59 AM
I built PepperShredder.......And I was thinking about feeding it with 24V. How will it work?
Should be cool! Just remember that the tube heaters still want only 12.6 volts though. So use a 7812. Or, as you have two tubes, another solution would be to wire together the two tubes' heaters in series.
Hey! Thats a good point. I will connect the heaters series. And will let you know!
Here is my Werevalve:
http://www.youtube.com/watch?v=K9mm_gXS-kE (http://www.youtube.com/watch?v=K9mm_gXS-kE)
I noticed the bite in this pedal and could think of no better name than The Werevalve:
Don't judge my playing to hard:
http://www.youtube.com/watch?v=K9mm_gXS-kE (http://www.youtube.com/watch?v=K9mm_gXS-kE)
(http://195.149.144.149/images/89/8991744263.jpg)
Notice the detail "ut" which is "out" in Swedish/Norwegian. The "t" in "ut" is actually the authentic ancient rune "Wolfcross" to protect against wolves. And not the natural kind. Of course the Nazis later miss-used it as a symbol for something else.
Valvecaster with 24V DC, use any polarity, 12AU7 tube.
I have built a few extra. Cost: 50 Euro/70 dollar.
Shipping from Sweden or Norway.
Hey I ran three valvecasters together and guess what? It sounds awsome! I dropped the input caps to .001uf on the first two ans .022uf on the third. Its still pretty fat. I also ran a 12ax7 in the second stage. Here is a link to youtube clip. http://www.youtube.com/watch?v=L0ZtpJ12C2A . Check it out and please give some feedback. good or bad is fine.
WOW! :icon_eek:
Yeah, WOW. Very good playing and good sounding pedal!
damn.. my valvecaster doesn't even comes close to this one.. Awesome sound, just that good.
I'm definitely doing something wrong..
Well, Thank you very much! :icon_redface: I will take those as great compliments! I am trying to figure out how to run these at 30 volts or so. I know the heater only gets 12.6 max so where do I hook up the 30 volts? To the anodes? I am looking for a schematic but I cant tell the mechanics of it from vero board layouts. ( iwish I wasnt such a visual person). Any one have a clue? ( its a rhetorical question, I know Renegadrian knows... ;) )
p.s. Differo, I just daisy chained three together to get that much gain. My single doesnt get that much ( although its still maybe my favorite tone..) and I had to build it twice before I even got sound out of it at all. Just keep going on them and they will sound good. I figured out using heat sinks keeps me from burning all my parts up while I solder. Go figure... Cheers Gentlemen!
Quote from: zambo on February 03, 2010, 08:05:29 PM
Well, Thank you very much! :icon_redface: I will take those as great compliments! I am trying to figure out how to run these at 30 volts or so. I know the heater only gets 12.6 max so where do I hook up the 30 volts? To the anodes? I am looking for a schematic but I cant tell the mechanics of it from vero board layouts. ( iwish I wasnt such a visual person). Any one have a clue? ( its a rhetorical question, I know Renegadrian knows... ;) )
Yeah, more voltage goes to the anodes - if you use my layout here (http://www.aronnelson.com/gallery/main.php/v/Renegadrian/Valvecaster-no-tone+elc3.jpg.html?g2_imageViewsIndex=1) (or follow to get the idea) you see a red wire that gives power to two res (R2-R3) that go to first and second anode (pins 1 and 6) and then on the same line pin 5 (one of the heaters) is connected - to apply different voltages, you can use that very same layout, just connecting pin5 to the +12V and whatever upper voltage you want to that row with the red wire!
HA! I knew you would know the answer! Thanks mister! I have read most of this forum and you are a lot of help to everyone on here. Thank you on behalf of all of us.
I think my next one will be 24 volts at least. Maybe more I'm not sure. I will have to figure out how to regulate the power so I don't get the dreaded hum. I dont think a voltage pump will power three valves together ( and I am considering four ) .
Thanks for your kind words, I am still a noob but yeah as I've got a little of "already done that" I got some little experience to share and maybe be helpful to someone... :icon_redface:
Regarding the voltage pump, what you must consider is the current that you need for the tubes...I guess you should start with a 1MA 12V PS - the heaters want 12V/150mA. The current required at the anodes is much less (around 15-20mA, but here I go guessing, following the tube datasheet).
So from the power input, you'd have one wire going to the heaters and one feeding the voltage pump. I dunno how much current can a voltage pump provide, but I guess it's enough to run a couple of circuits...
Read Rick's experience with the 555 smps - as the circuit needs more current, you have to step down a little with voltage, but hell I guess you can be still quite happy to have 150V and not 200V from that smps...
Here is clip of my latest build. They are getting better. Better tone control on this one. Still has scratchy gain pots. Any fixes for that anyone? http://www.youtube.com/watch?v=qbDJYMAp6Mo
I just got my hands on a bunch of tubes (mostly 12au7 but some others too) and tried last night in my valvecaster - actually I don't know about you guys but I liked the sound of 12AX7 in my valvecaster! It doesn't differ that much from AU type, its quieter a bit but there is some overdrive to it, well basically it works - I tried ecc84 too that one was no hit - it worked but rather quite with little to no overdrive. What I like with tubes and particularly with this project is that almost everything works :) and its wasy to swap and test.
Hi!
Nice design! built it with first cap at 0,022uF, and using 24v. Ran it with a battery (UPS), not humming at all.
Tried out some different power supplies, none of them made the same sound.
Anyone know why a power supply for a laptop is making a hi frequent hum? Looked at the current in a oscilloscope, can't see anything.
Thank you all for a grate forum! Made me into a DIY Tube addict!
Quote from: volund on February 12, 2010, 08:40:16 AM
Tried out some different power supplies, none of them made the same sound.
Anyone know why a power supply for a laptop is making a hi frequent hum? Looked at the current in a oscilloscope, can't see anything.
My best guess is that most power supplies for computers and laptops are switched-power supplies, which operate at a high-frequency
Quote from: zambo on February 08, 2010, 09:19:43 PM
Here is clip of my latest build. They are getting better. Better tone control on this one. Still has scratchy gain pots. Any fixes for that anyone? http://www.youtube.com/watch?v=qbDJYMAp6Mo
:icon_eek: The tripple tubber sounds great!
Thanks! I am actualy going to build a 4 tube version so I have more options for clean dirty and lead boost ( still trying to figure out switching on that though ). I have been gigging with the three tube version and getting really positive response from it. I recomend trying it if you are in a hi gain situation. I heard it sounds better than a triple rectifier from the audience ??? :o :icon_surprised:
Quote from: BlueJay on February 13, 2010, 01:22:02 PM
Quote from: volund on February 12, 2010, 08:40:16 AM
Tried out some different power supplies, none of them made the same sound.
Anyone know why a power supply for a laptop is making a hi frequent hum? Looked at the current in a oscilloscope, can't see anything.
My best guess is that most power supplies for computers and laptops are switched-power supplies, which operate at a high-frequency
I Make my own power supply using a transformer and a Velleman 1Amp PS board. It's cheap and stable. Never had any problems with noise no matter which pedal I'm using. Nice thing is that the board allows you to modify the output voltage to taste
Had the thread bookmarked for a year now. Finally built this thing today!!! I used the basic layout in the first few pages and added a switchable input cap. Here are few pics:
(http://img.photobucket.com/albums/v693/BigDanPhotos/IMG_0040.jpg)
(http://img.photobucket.com/albums/v693/BigDanPhotos/IMG_0045.jpg)
Has anybody build this Twincaster layout? Is it correct?
Dan
Quote from: Renegadrian on February 19, 2008, 02:49:41 PM
Based on the Twincaster schem, seen some pages ago and developed by Dano (again) I'd like to show you my Twincaster VERO version...
Here is my vero (should be correct, but hey...)
(http://img220.imageshack.us/img220/460/twincasterv01yq0.th.jpg) (http://img220.imageshack.us/my.php?image=twincasterv01yq0.jpg)
Checked it again, still seems correct - I guess you'd have 99% of getting it fired up alive and kicking arse right away...
Still haven't built it myself tho'
Hey guys! Here's my valvecaster. Also my first post, although I've been lurking (on this thread specifically) for quite some time. It all started when I had this unused 9v power adapter from a modem/router. Was gonna use it for my pedalboard, but it already had a working power supply, so I thought I'd use this for a pedal build. Switched polarities and it's good to go. Regulated also, as far as I can measure. Then an abandoned pedal build came into my hands (some guy trying to build a jcm800 emulator?), complete with the enclosure, DPDT footswitch and some other stuff. At the time I was most interested in building the valvecaster, so on to it!
First I used a perfboard (or veroboard??) just to see if it was a pedal I'd like. Also took the time to experiment with components. First was input cap values, after a while I found out I was very happy with a .010 uF, and that it's all I need to rawk! I just use it to boost my amps. Amp slightly crunchy, valvy tone and vol always maxed out, and just adding a bit of gain on it to taste.
(http://i252.photobucket.com/albums/hh19/siore/Image0081.jpg)
(http://i252.photobucket.com/albums/hh19/siore/Image0083.jpg)
(http://i252.photobucket.com/albums/hh19/siore/Image0084.jpg)
My mistake right here... is not following any of the layouts already posted. :icon_lol: Each component had a spot on the board so... TOO MANY HOOKUPS!! Then I tried the vero layout on aronnelson.com's summary PDF file (I believe the proper credit to this is Renegadrian's?). Then at this time I got the enclosure (from the abandoned pedal build) delivered to my doorstep. Following the new layout, and admittedly rushing to put it all together in the box, I ended up with this monstrosity. :D :D :D
(http://i252.photobucket.com/albums/hh19/siore/Image0085.jpg)
(http://i252.photobucket.com/albums/hh19/siore/Image0086.jpg)
(http://i252.photobucket.com/albums/hh19/siore/Image0088.jpg)
So I took a few steps back, removed everything once again, and re-housed with some decals and "label plate" (which I just put there to cover old holes from the previous build). At this point, I felt like I still had way more wires than needed, so I decided to go point-to-point, but I did some modifications to the layout, basically just switching ground here and there so they follow a more separated ground route. E.g. dedicated heater ground route, switch grounds, signal grounds, lead twisting, routing, then leading them all back to the jacks. Not that it matters at all ;D as it worked fine as shown on the layouts, but I wanted to prep myself for an amp build in the future, so I figured I'd have fun with it that way.
(http://i252.photobucket.com/albums/hh19/siore/Image0099.jpg)
(http://i252.photobucket.com/albums/hh19/siore/Image0100.jpg)
(http://i252.photobucket.com/albums/hh19/siore/Image0097.jpg)
(http://i252.photobucket.com/albums/hh19/siore/Image0098.jpg)
Oh, in the end I replaced the formal looking 'valvecaster' plate and put in something more personal. I chose him, because I dunno if you guys play mortal kombat........ but the dude just WINS. 8)
(http://i252.photobucket.com/albums/hh19/siore/Image0105.jpg)
(http://i252.photobucket.com/albums/hh19/siore/Image0107.jpg)
(http://i252.photobucket.com/albums/hh19/siore/Image0109.jpg)
I'm liking it a lot. Thanks to matsumin-san, dano, renegadrian, that frequencydude, and all the others who have made this pedal build possible. Yes, I'm still using it with 9v (and a 12au7 tube), and for boosting purposes, it's epic.
siore
Quote from: Renegadrian on February 16, 2010, 08:02:45 AM
Checked it again, still seems correct - I guess you'd have 99% of getting it fired up alive and kicking arse right away...
Still haven't built it myself tho'
I built your 0.11 version of the Twincaster, works perfectly. Uses 12DW8 12V tubes, so pin 9 is connected to ground as it's a separate diode on these. They draw nearly 1A as a pair, but sound great.
(http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=23025&g2_serialNumber=5)
(http://farm3.static.flickr.com/2596/4079939969_612bb99693.jpg)
siore, I really enjoyed your build report - it seems you already learned a lot, trial and error, and so on...
I like the first boxed version, looked "cyberpunky" somehow...
Glad you like your pedal!!!
juansolo, thx for using my layout!
OK guys... this is my first post here, please don't kick me for my bad English :P
I'm reading this tread from about 2 months, and this week i built a twincaster, with 12Au7 + 12ax7, i followed this circuit:
(http://www.beavisaudio.com/Projects/ValveCaster/twincaster.gif)
i corrected the error in the middle, and exchanged connections on second tube from lug 4 to lug 5, as suggested in the first pages (cit: "12ax7 and Au7 are pin to pin compatible except pin 4 and 5 that got inverted in grounding and heating"). Is this practice correct or i had to leave the lug connections as shown in project?
i added also a 3PDT switch, so i have a full bypass pedal. I added also a "always on" blue led that lights up when the power plug is connected and a green led that lights up while the switch is not in bypass position. The leds are working correctly.
I'm using a 3-12 volt 400ma DCa, but the stompbox is not working. Tubes are not lighting up, and when i connect it to the amp i get only a big hiss in bypass mode and nothing in work mode. Can u guys help me checking the circuit?
Hi there, and welcome! Your english is also quite good!
First, if you have no sound when bypassed, there must be something wrong! I believe that you should use a PS with more power, 400 mA for 2 valves couldn't be enough...But hell, before that you must see why there is no bypassed sound!
I dunno about the pins 4 and 5, AFAIK you could use them both ways and get no difference...
The circuit you posted should be correct, let us see your work then, post some pics and we'll check!
A.
as reneg suggested by chat, i checked the tubes... i connected them directly to the power plug (i used a 2000ma 9v DC this time) and it happens something strange... The 12AX7 lights up but remains cold, and the 12AU7 remains dark but becomes warm.
I'm a bit confused :icon_eek: The Tubes are new, bought them 3 days ago.
This is a (bad) shoot of the circuit. It's just a trial, i must fully rewire it i guess, but all connections appear good.
(http://img268.imageshack.us/img268/4927/foto293p.th.jpg) (http://img268.imageshack.us/i/foto293p.jpg/)
Center resistors heats leds, the two red cables who starts from center heats the tubes, the two red cables going from 3dpt to jack plugs carry audio signal.
Except 2 cables (i had not enough blue one :P ) i used blue for audio, red for DC and black for ground.
This is the outside... 4mm MDF painted with no-gloss nitro puliurethane. Looks good :D
(http://img297.imageshack.us/img297/7138/foto296q.th.jpg) (http://img297.imageshack.us/i/foto296q.jpg/)
@ DPV
C3 should be connected to pin 2 of the third stage, not pin 1. You also need to add a grid leak resistor (or a pot) from pin 2 of the third stage to ground - so it looks similar to C1/R1.
R3 of the second stage is just floating in that schematic, it should be connected to +ve.
12v/400ma should be just enough for this circuit, but 12AX7 really don't perform at such low voltage, maybe try a 12AU7 instead.
Pins 4 and 5 are interchangeable, some tube designs use AC for the heaters.
Don't expect the tubes to glow like light bulbs - you may just get two small pinpoints of glow in each tube.
Quote from: frequencycentral on February 17, 2010, 07:19:59 AMC3 should be connected to pin 2 of the third stage, not pin 1. You also need to add a grid leak resistor (or a pot) from pin 2 of the third stage to ground - so it looks similar to C1/R1.
Ok i already corrected that pin, pin6 of first stage is connected with a cap to pin2 of second stage. I'll try adding that resistor.
Quote from: frequencycentral on February 17, 2010, 07:19:59 AMR3 of the second stage is just floating in that schematic, it should be connected to +ve.
No, is connected to +v
Quote from: frequencycentral on February 17, 2010, 07:19:59 AMDon't expect the tubes to glow like light bulbs - you may just get two small pinpoints of glow in each tube.
I was just wondering about the different reaction of the tubes... thx for help.
Any Other suggestion?
You might start with sorting out the bypassed sounds or should I say no sound; this should be the starting point as this is only wiring problem has nothing to do with the circuit. It happens sometimes that these simple (yet annoying) problems cause another problems like circuit not working in 'work' mode.
DPV, check your pin 4 and 5 connections maybe? Sure they're interchangeable, but know that one pin takes DC, the other shunts to ground. So if you have other connections that use one of the two pins for ground, then suddenly you interchange them, you just connected a component to the +9v supply. IMO, heater grounds should be isolated from signal grounds, but it also works as shown in the layouts. You may have already done this, but still, work your way from the schematics. The layouts could have a slight error (for instance the tone pot functioning in reverse in one of the original layouts), but the schematic will show you which pin or component connects to which.
I have also had 1 12ax7 that worked in a valvecaster but 3 that didnt. That wouldnt solve your bypass issue but if you dont have sound in "work" mode I would try 2 12au7 s .
Also decided to lay out my creations on this scheme. That one I did for the first time http://virtue-harp.narod.ru/lam2.JPG, bypass mode with cold bypass. That one made my friend http://www.gb-music.ru/george/walvecaster_2.jpg, inside looks http://www.gb-music.ru/george/walvecaster_4.jpg. Tremolo pedal combined with a tube http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=40279&g2_serialNumber=1
My second pedal http://virtue-harp.narod.ru/0918191018.JPG
Third http://virtue-harp.narod.ru/1020015147.JPG
Type in the second and third http://virtue-harp.narod.ru/1020200749.JPG
Fourth (http://virtue-harp.narod.ru/0212233716.JPG)
Type in http://virtue-harp.narod.ru/0212233845.JPG
Subject to the Russian forum about the tube-like pedal http://www.forum.harmonica.ru/viewtopic.php?f=19&t=127115
First post. Built a Valvecaster a few weeks ago, and it sounds great! Really warms up the front end of a SS amp.
I FOUND OUT WHAT THE TONE KNOB IS FOR!!!!
Ok, so I thought I agreed with the tone knob delete, but I already built the valvecaster, so I left it on. Then while fooling around with it and my Peavey Bandit, I found out why it's a good thing. I've been trying to find something smaller to take to gigs, as I am SICK of lugging around my 5150 and Marshall 4X12 of HEAVY celestion V30s... So I decided on a Peavey Classic 50. I don't have the cash for that right now... but I do have a 80w Peavey Bandit 112 that's loud enough for bars, just doesn't sound right. Putting the valvecaster in front of it sounds great, just turn the knobs up all the way and it sounds smooth and creamy, but at higher volumes it starts getting all twitchy. But I found that I could get really respectable gain and tone out of the Bandit if I put the valvecaster in the fx loop, play through the lead channel with the pre at about 5 and post at about 8, t dynamics at 10 presence at 7 and on the valve caster turning the gain and TONE down somewhere between 40% and 80%, and use the volume knob as a power brake. Great tone at any volume! PERFECT! Well, as good as a Bandit is going to sound, anyway.
Note: I'm using a early 90's LP studio, playing punk, and I have the gain and thrash buttons pushed in.
Edit: I'm using the Dano layout - on the socket build.
Right, thx for the report and welcome! Feel free to post some pictures of your Valvy!!!
Hi,
I discovered a cool thing. If you do your own vocals, try hooking the Valvecaster to your regular DI-guitar input. And THEN use a Whirlwind Little IMP impedance transformer to hook a SM57 microphone (or any other mic that doesn't need 48V phantom power) to the input of the valvecaster. Nice tube saturation and vocal fattener!
For some reason I get less static and hum using the impedance transformer, suggesting a little impedance transforming would to the valvecaster some good for guitar also. If anyone has a spare transformer that doesn't do to much with the signal feel free to try it out.
Quote from: snickers_163 on February 23, 2010, 02:06:04 PM
First post. Built a Valvecaster a few weeks ago, and it sounds great! Really warms up the front end of a SS amp.
I FOUND OUT WHAT THE TONE KNOB IS FOR!!!!
Ok, so I thought I agreed with the tone knob delete, but I already built the valvecaster, so I left it on. Then while fooling around with it and my Peavey Bandit, I found out why it's a good thing. I've been trying to find something smaller to take to gigs, as I am SICK of lugging around my 5150 and Marshall 4X12 of HEAVY celestion V30s... So I decided on a Peavey Classic 50. I don't have the cash for that right now... but I do have a 80w Peavey Bandit 112 that's loud enough for bars, just doesn't sound right. Putting the valvecaster in front of it sounds great, just turn the knobs up all the way and it sounds smooth and creamy, but at higher volumes it starts getting all twitchy. But I found that I could get really respectable gain and tone out of the Bandit if I put the valvecaster in the fx loop, play through the lead channel with the pre at about 5 and post at about 8, t dynamics at 10 presence at 7 and on the valve caster turning the gain and TONE down somewhere between 40% and 80%, and use the volume knob as a power brake. Great tone at any volume! PERFECT! Well, as good as a Bandit is going to sound, anyway.
Note: I'm using a early 90's LP studio, playing punk, and I have the gain and thrash buttons pushed in.
Edit: I'm using the Dano layout - on the socket build.
Hey man, I think the valvecaster sounds great with the peavey transtubes. I tried it on my peavey blazer, I have the gain around 1'oclock, and use the valvy with all the knobs turned up except the gain knob, which I keep low. It definitely adds top end sparkle to the cleans when you roll back the guitar volume, compared to rolling back with just the amp on full. Wish I could try it on the effects loop, but I (stupidly) sold my bandit years ago. But in front, I agree with you that the peavey takes it well. :)
This is so funny...I also run a trans tube peavy half stack ( and I have the combo as well ) but I run into the clean side and use a three tube version. It sounds awesome too me.I cant find a better tone right now and I have access to a marshall jcm , 5150, several fenders etc. I just like the peavy the best. Is this weird?
Yes
Very weird
:-)
Ok, have it totally dialed in now. Played a small bar the other night. The pre gain was at about 3 and the post at about 8, presence at 8 and t dynamics at about 80%. Valvecaster in the fx loop was: gain at 10, tone at about 6ish, and volume to taste. Bridge pickup cranked on my les paul. Let me say this thing sounded quite a bit like my 5150, and definitely kept up with the other guitarists Classic 50 (4x10). Very impressive. Saved my back not having to lug the half stack!
I dont mean to hi jack the thread but has anyone tried the runoffgroove big daddy distortion into a valvecaster. It is truly a thing of beauty if you like solid state grind ( which i do as well). Simple build and very rewarding. I think it uses a .0068 mf cap and I subbed a .0047 with good results...
Ive been struggling to get my dual valvecaster to work properly. I did have a working version of the single tube unit but then decided to try and upgrade it.
Heres all the info I can think of, if theres anything else that I can provide that will help in diagnoses please let me know, if all else fails Ill just go back to the single tube and call it a day:
I used this schematic as the basis:
(http://farm5.static.flickr.com/4033/4402512394_cd824c682e_o.jpg)
I created my own perf board layout, which I added leads to the different tube pins from the proper points on the perf:
(http://farm3.static.flickr.com/2692/4401747595_a8f12728d2_o.jpg)
Other notes:
Im using an unregulated power supply, which is why I added the voltage regulator with 100uF cap to the +12V as described in this thread.
All my grounds come together on the perf board, is this correct?
At the voltage regulator there is continuity (beep from multimeter) between my negative (middle pin) and output (right pin), should this be like this?
The voltages at the various pins, I used the main ground on the perf board as the negative lead on my multimeter for all tests:
Tube A:
1> 2.48
2> -0.36
3> 0
4> 0.04
5> 11.6
6> 4.26
7> -0.42
8> 0.04
Tube B:
1> 4.66
2> -0.7
3> 0
4> 0.01
5> 11.56
6> 4.94
7> -2.05
8> 0.015
The problem is that there is an (almost) constant hum as soon as I plug the power in. This hum gets louder/quieter as I move the volume knob. The tone knob does change the tone of the hum. The hum seems to disappear (or at least gets too quiet to be noticeable) when I play the guitar then comes back when I stop. When I am playing the sound is very distorted, sometimes sounding almost like a fuzz effect, or really bad distortion.
from reading this thread I think that its either a grounding problem or a problem with my power supply, if anyone could provide me any help with this it would be great.
Im probably forgetting some other info, If I think of it Ill post. Ill also see if I can record a little MP3 demo a little later
Thanks!
I'll bet anything it's the power supply. I first tried mine with an unregulated 9v power supply and it made an awful noise. Bought a regulated supply and now all is good. On a side note, sometimes, even with a regulated power supply, if I have the wall wart too close to the amp I get squeal.
I think it was the power supply too, Im thinking that it wasnt strong enough for 2 tubes, it is rated for 800mA @ 12V and from what I read the regulator likes more then twelve to start with so it was probably running out of juice.
I rebuilt the single tube one and its working great! The hum is there when I turn it on but it fades away within 2-3 seconds and then its fine.
You should look at renegadrian twincaster vero layout. His stuff always seems to get good results. Power supply is huge too but I think 800 ma should work. Each tube wants about 200 ma. I built a version with 3 tubes and no hum. Used a onespot 9v power supply. :icon_wink:
im starting work on a tube od that's kindof running on 9v. Thanks to rick, i'm using a Nixie ps to get 125V for a single 12AX7. Some of you may remember the argey bargey in the pictures thread, but you'll be glad to know, that particular effort has been dismantled and i'll be using the box for a little FX Loop for my KP. :)
This is going in a bigger box. it's the same size as a Little big muff, or the big muff with tone and wicker, so i'd hardly call it excessively big.
My previous attempt was not unlike a ZVex Super duper, with 2 switches, 2 gain stages and 3 controls. This is a bit more... practical? It still has 2 gain stages, but one is only a little boost, and quite clean. The other is really gritty. So it'll have 4 controls; Boost, Drive, Tone and Volume. Boost is the cleaner stage. It'll be strong enough that if you've a high output pickup, on full, it'll probably just start to clip. Drive on the other hand will go into cutoff and clip at around 40-45%. There's tonnes of tonestacks out there, but i think i'll probably base it on the Big Muff filter. It's nice and easy, and gives a pretty good range.
One of the major problems with the last project was that nothing really was mounted. This time, it's kinda the opposite. I'm just working things out now, but it looks like the board will be mounted to the 4 pots and the two jacks. As for the tube, i'm ordering 10 nice new sockets, and 28 tubes. :D The 10 sockets are the ones with the rings with screw holes. I'll probably mount one side of the tube to the outer wall of the box, using a small L-Plate, and the other side will be mounted to the top wall of the box, again, with a small L-Plate. I've still got 2 x 12AX7's i pulled from an old philips turntable, but the tubes i'm ordering are old russian 12AX7's (and some mini pentodes ;) ) so i'll try out the russian tubes too.
The only forseeable problems i have so far is time (i'm mega busy with uni at the moment) and ventilation. Where the tube will sit, should i put a hole or two for ventilation? particularly if it's going to be running 125V?
Vent it. I hear even at 9 to 12 volts you should vent the box when they are inside. I was talking to an amp maker about it. He said vent the sides and front if you can. That way no one can spill beer into it. I was just playing in a bar last week that had a leaky tub of ice by my rig and I was real glad to be running at 9 volts. 125 might have scared me to death :o
cool. Cheers zambo. I left my camera in the studio in uni so no pics till monday or tuesday. It'll only be pics of the enclosure, but you can see my mammoth improvement efforts. :D
guys, I can hardly understand what's happening.... 12AU7 needs a minimum of 100 V plate voltage, how could it run on 9 V?
read this:
http://www.nj7p.org/Tube4.php?tube=12AU7
I don't believe this valvecaster would ever work with 12AU7
I am looking into building something similar, but I will have to use 100-250 V
Quote from: motorhead on March 08, 2010, 04:41:05 AM
guys, I can hardly understand what's happening.... 12AU7 needs a minimum of 100 V plate voltage, how could it run on 9 V?
read this:
http://www.nj7p.org/Tube4.php?tube=12AU7
I don't believe this valvecaster would ever work with 12AU7
I am looking into building something similar, but I will have to use 100-250 V
That says "Typical operation", not "Minimum operation". You'll see on the Plate Characteristics graph that the X-axis starts at zero, not 100!
correct
but who can guarantee any liniarity or characteristics in that range? it's probably random
Nobody guarantees linearity. It's a guitar distortion pedal, not a hi-fi preamp. The lack of linearity with such a low plate voltage is exploited deliberately.
Quote from: motorhead on March 08, 2010, 04:41:05 AM
guys, I can hardly understand what's happening.... 12AU7 needs a minimum of 100 V plate voltage, how could it run on 9 V?
read this:
http://www.nj7p.org/Tube4.php?tube=12AU7
I don't believe this valvecaster would ever work with 12AU7
I am looking into building something similar, but I will have to use 100-250 V
Do you really believe that?! Strange, I have built 9 Valvys (at 12V) for me and some friends - they are working so good!!!
So please read people's reports before making silly statements...
:o After two and a half years and over eighty pages of this thread we find that all of our many Valvecasters don't work? ::)
I'm not saying that, but I suspect it's a matter of chance rather than science. As a matter of fact, I found some 6-7 tubes myself and i will build one
if you look at some of the characteristics, you will not see the line going down until 0V Plate voltage, so 9V is clearly out of range
that's why I would not expect much out of the circuit, maybe experimenting with various tubes I'll get a good sound, but it's more of an experiment than science
modern science is based on experiments...Isn't it?! :icon_wink:
To say, one of the rules of modern science approach is that you must be able to duplicate your "invention" in every moment.
As you can read, The valvy successfully falls in that rule.
the initial tube was a 12U7 i think
http://www.nj7p.org/Tube4.php?tube=12U7
the "science" looks better with that tube ?
Hi! Quest about the dual circuit. C3, way is it so large?
it's what I suspected, the miniature tubes have completely different characteristics
so it's not supposed to run with a starved plate, but it became that way by changing the tube
i'll go with a high voltage design, since I can't find a miniature tube, apparently it will get closer to the tube amp sound
Motorhead... perhaps you should just try building one. A 12AU7 tube can be obtained cheaply on ebay or through various other websites. Or, go look up some of the ones that have been built on youtube. You'll see that they have a very nice sound, and indeed work quite well.
(http://www.santuariofontanellato.it/Pasqua%202008/incredulita_SanTommaso.jpg)
I think everyone is right- Obviously, the circuit works. That's not in question. The point of the project isn't to recreate an optimally functioning 12**7 tube gain stage. If you want that, just go out and grab any tube amp schematic and recreate the first stage: Bam. Done.
The purpose of this project was to allow pedal builders that don't work with high voltages to do something with tubes, without cooking their insides.
Is a 12**7 tube meant to run on 12 volts? No. Does it? Yes. Does it sound good at 12v? I'd say good, but not magical. Would it sound better at 100v? Probably, but that would defeat the purpose of this project.
Maybe the circuit needs a "For Entertainment Purposes Only" disclaimer.
disclaimer is a great idea. :icon_smile:
Hey everybody,
I haven't posted in years,, but every once in awhile pop in and check things out and this time had to comment,, sorry if this comes across a bit harsh.
Motorhead,, have you worked with tubes before? it doesn't sound like it and I hope you take care when you build your high voltage pedal.
As for the starved plate designs being a "chance" thing,,,,, I imagine it was just "chance" that the tube driver,, the mini boogee, the tonebone classic and hot british,, the aria tube overdrive,, the nady tube overdrive,, the behringer tube overdrive,, the various vox tube pedals,, the various maxon tube pedals, and so on and so forth were developed.
As you will notice,, tube curves are exactly that,, curves,,, they don't drop off totally at 9.7 volts or 15 volts,,, they curve. Do they sound the same as at higher voltages?,,, no,,, does that mean they sound bad? absolutely not. Most of the characteristics you want in an overdrive will be in a starved plate design,, breakup,, compression etc,,,,,NOT LINEARITY,,,, will it sound like a triple rectifier, absolutely not,,, neither does a tube screamer,, a boss overdrive,, or any other overdrive out there(not that a triple rectifier is at all linear).
As for your comment on the mini tubes,,,, the 12u7 follows the same general curves as the 12au7, physically has the exact same plate structure, sounds the same ( yes I have both) and quite possibly is just a 12au7 relabeled. Yes the subminiatures follow different curves but again,,, linearity is not the goal!
The fact is,,, its been done time and time again,, and this design has been researched so thoroughly by the guys in this thread that it has me a bit speechless that you would pop in 80 pages later and act like it was a fluke,,, ummm, what?
I mean you could build it and try it,, its so simple it would take an evening at most, or don't bother because you don't believe it works(even if the thousands of pedals made with a starved plate 12au7),, but most people are here to learn too and if thats your case,, then remember its hard to learn when your close minded.
Regan
Quote from: motorhead on March 10, 2010, 11:21:05 AM
i'll go with a high voltage design, since I can't find a miniature tube, apparently it will get closer to the tube amp sound
Be careful, it might just be pure speculation that a tube preamp sounds like a tube preamp. ;D
Quote from: Regan on March 12, 2010, 03:45:54 AM
cut
most people are here to learn too and if thats your case,, then remember its hard to learn when your close minded.
/cut
That sentence makes me think of my first Valvy - it was one of my first pedals made and yeah I had a great surprise when done - how can a tube with just a few components and working at 12V can sound so good!!! it left me like http://www.youtube.com/watch?v=QkjD3D5FgmE :icon_lol:
well, that's exactly what I'll do when my tubes will arrive: ECC802 S and ECC803 S
"The ECC802S is the uber premium version of the ECC82/12AU7 tube with extra internal structure, pure copper grid supports and 10,000 hour life ratings. These tubes were made in the Siemens Munich, Germany factory"
and I'll build both the valvecaster and probably some fender or vox or whatever preamp, and let you guys know the difference
that's right, i never used tubes before, but I'll survive a shock of 100 to 250 V, hopefully :icon_lol:
if I survive, the power amp is next :icon_wink:
Quote from: motorhead on March 12, 2010, 09:50:48 AM
and I'll build both the valvecaster and probably some fender or vox or whatever preamp, and let you guys know the difference
No offence, but I think everyone already accepts that the Valvecaster is a pedal circuit. It's for use
with a preamp, not instead of one.
ECC803 S is a 12AX7 - you won't get great results with that tube in a Valvy...
Why cant we use valvy as a pre amp? Forgive the ignorance on my part. Ps....what comes out the business end of a valvy ohms wise and voltage wise?
Can I use this schematic as a preamp for an tube amp project I'm working on? :-\
I guess (an educated guess :icon_lol:) that you can't use it as a preamp, since plate voltage needs to be higher than 12 V, in order to achieve some sort of gain out of a tube - look at the curves
or you can add an op-amp at the end, and increase the overall gain, but you won't be able to call that a tube preamp
ecc802 or ecc82 is equivalent to 12AU7, so it should work with valvy
Quote from: frequencycentral on March 08, 2010, 12:36:48 PM
:o After two and a half years and over eighty pages of this thread we find that all of our many Valvecasters don't work? ::)
Finally, you guys have caught on to my evil plan.
Quote from: motorhead on March 12, 2010, 09:50:48 AM
that's right, i never used tubes before, but I'll survive a shock of 100 to 250 V, hopefully :icon_lol:
if I survive, the power amp is next :icon_wink:
You might want to suggest that your wife/roommate/family, or whomever you live with, take a CPR class. And offer to pay for it too. ;D
Seriously though, read up on some safety before trying anything high voltage.
Quote from: motorhead on March 16, 2010, 05:07:19 AM
.......since plate voltage needs to be higher than 12 V, in order to achieve some sort of gain out of a tube..............
I don't even think it's worth arguing the point any further. If you choose not to believe this then that's your call. Whatever. There are worse facts to choose not to believe I guess. I despair. I don't think I can bear to look at this thread any longer.
I have used the valvecaster as a preamp for a lm386 power amp ( or lack of power amp at a raging .3 watts!!) and it seemed to work fine. I dont know what a "real" power amp wants to see at the input and if it matches the output of a valvecaster. If I only knowed the answer to these two things...... It seems like the answer was in these 83 pages somewhere .
Hi everyone. I'm Paul. After reading some pages on this forum. I wanted to see if I can build one of these pedals. So far I got it to work but I think I would want more overdrive. Something a bit tighter sounding. I have heard some of the sound clips from Shimster and Zambo and they sound great. I want to go for something like what they have. I haven't had much time to mess with the caps and resister but I'm working on when I have time. Any help would be great. Thanks. Noob. ;D
All the n00bs are welcome as long as they want to have fun with this $h.t!!! :icon_wink:
The Valvy is a good booster/overdrive but yeah it's not a gain monster...If you're after some more gain, why don't you try my TUBE STAR?! It's as easy to build as the Valvy and yeah it gives you that extra kick!
you have a schematics for it?
Tried the forum's Search button?
Quote from: paulyy on March 17, 2010, 03:09:06 AM
Hi everyone. I'm Paul. After reading some pages on this forum. I wanted to see if I can build one of these pedals. So far I got it to work but I think I would want more overdrive. Something a bit tighter sounding. I have heard some of the sound clips from Shimster and Zambo and they sound great. I want to go for something like what they have. I haven't had much time to mess with the caps and resister but I'm working on when I have time. Any help would be great. Thanks. Noob. ;D
Thanks for the welcome. I figured this wasnt going to be a high gain project but I do have a thing for OD pedal as well. I tryed hook up a second tube to my VC but no luck. I got both to power up but only one was making sound. I tryed to read the schmatics but I cant read schmatics. Ill just start tweaking with what I have so far. Thanks.
Quote from: Renegadrian on March 17, 2010, 08:13:54 AM
All the n00bs are welcome as long as they want to have fun with this $h.t!!! :icon_wink:
The Valvy is a good booster/overdrive but yeah it's not a gain monster...If you're after some more gain, why don't you try my TUBE STAR?! It's as easy to build as the Valvy and yeah it gives you that extra kick!
I ment to put your quote in and not mine. Still trying to figure out how this forum works :icon_redface:
Should you need more than a standard Valvy, try the twincaster, which is 2 Valvies!
Quote from: Renegadrian on March 17, 2010, 03:37:25 PM
Should you need more than a standard Valvy, try the twincaster, which is 2 Valvies!
That's what i was going for but couldn't figure out. It sucks that I have to be so visual :icon_mad:
Ok. I figurerd out how to make the daul VC and works really well. Im using a 1spot 9V to power it for now untill I can find a good 12V. I found out that 1spot doesnt make a 12V any more. Witch SUCKS! Id post pics but cant figure out how to post them ???
(//)F:\IMG_2062.JPG
(http://F:%5CIMG_2062.JPG)
Trying to put some pics up but no luck. Ill try latter.
You need to host the pics on a site somewhere - we can't all see your F: drive! :)
i just finished building mine and i ran into a problem..
i have got a signal,when its bypassd.
and when i turn it on,the led works and when i turn the volume up i just hear a hum...
any ideas?
It's wired up wrong.
Sorry if that seems unhelpful, but you need to do some basic debugging on this. There's a sticky thread about that.
maybe we need some more info to get to the problem...Judging on the little you wrote, the only thing that we can say is...That it's wired wrong!
sorry for my last post i posted it after i tried to solve the all day... i dident think clearly...
after i looked at the debugging post i checked things out so.
this is where i got the idea to build the valvecaster http://www.mylespaul.com/forums/pedals/71001-diy-tube-overdrive.html
i checked the wiring 3 times and all seems in place,im using a 12au7 tube,and im using a 3PDT switch.
i get a signal when its bypassed,and when i turn it on the led turns on,and when i turn up the volume i hear a hum and when i turn up the volume more the hum gets stronger...
the tube works and it gets hot and glows.
im using a 9 volt dc supply
i measured the voltage on the tube legs,when the gain was fully opend:
1- 10.03
2- 0
3- 1.44
4- 0
5- 12.23
6- 4.75
7- -0.24
8- 0
9- 6.10
It's not a regulated wall wart, I think...You got 12.23 at the heaters (which is very good for that kind of tube, running at 12V)
pin 4 is ground so 0V - pin 9 halves the voltage, so it should be correct to have that voltage on pin 9, altough pin 9 isn't connected to anything, right?! For other voltage references, you should read this chart by Rick
Pin 1: 3.02v
Pin 2: -0.518v
Pin 3: 0.00v
Pin 4: 0.00v
Pin 5: 11.97v
Pin 6: 8.21v
Pin 7: -1.285v
Pin 8: 0.00v
Pin 9: 5.91v
Take measurements from yours with the tube in the socket, power engaged, and everything set to maximum
What is unusual is voltage on pin 1. check the resistor at that pin!
and also pin 3.
I finished mine, too! :)
well, it's not exactly the valvy... it uses more than 200 V :P
and I couldn't stop at the preamp stage, I made an entire amp ;D
and it sounds damn good, although the output transformer isn't exactly what the schematic demands, but what the hell... it's an all tube amp, after all, I recomend it to you all!
http://ax84.com/sel.html
Hi all, newby here,I have read all thro this and not found an answer to my question below. I have built a 386 with a marsha pre amp and wish to replace the pre-amp with this valvy and run it off 9v to start and move to 12v when I build my reg supply. I have a stratoblaster built in to the guitar which gives a nice boost to the marsha 386 when full up and a nice clean as I turn the gain down on the SBlaster.
The question I have is: can I omit the gain pot on the valvy as I already have the gain on the 386 and guitar?Do I just leave pin 3 vacant?
Thanks all Barrie :)
Quote from: dano12 on December 12, 2007, 09:22:41 AM
Here's a diagram for using a 12AX7 as a clipper pair based on info from another thread here:
(http://www.beavisaudio.com/Projects/ValveCaster/TubesAsClippers.gif)
has anyone got this configuration to work as clipping diodes in an SD-1 ????
I just remembered I had seen it somewhere ie page 40 answer by Frequency Central it will not work with pin 3 open,now thinking a mid point resistor ie 25K ish and work from there?any thoughts please? Thanks.
;) Well,I just finished building it and guess what ??? WORKED first time :D now thats a first :icon_biggrin:
Lovely tones and off 9v as well, get my psu regulated now and away we go and experiment :icon_cool:
Big THANK YOU ALL for this post.Cheers all I owe you all a drink-i-poo. Regards Barrie
Quote from: MetalGod on April 03, 2010, 05:27:17 PM
Quote from: dano12 on December 12, 2007, 09:22:41 AM
Here's a diagram for using a 12AX7 as a clipper pair based on info from another thread here:
(http://www.beavisaudio.com/Projects/ValveCaster/TubesAsClippers.gif)
has anyone got this configuration to work as clipping diodes in an SD-1 ????
I used this same layout in my SD1 and it worked fine. 1 and 8 go to D6 and 3 and 8 go to D4. I left D5 stock. Hope that helps. Id post pics but don't know how. :icon_question:
Quote from: paulyy on April 07, 2010, 11:00:32 PM
Quote from: MetalGod on April 03, 2010, 05:27:17 PM
Quote from: dano12 on December 12, 2007, 09:22:41 AM
Here's a diagram for using a 12AX7 as a clipper pair based on info from another thread here:
(http://www.beavisaudio.com/Projects/ValveCaster/TubesAsClippers.gif)
has anyone got this configuration to work as clipping diodes in an SD-1 ????
I used this same layout in my SD1 and it worked fine. 1 and 8 go to D6 and 3 and 8 go to D4. I left D5 stock. Hope that helps. Id post pics but don't know how. :icon_question:
the pedal still 'worked' when I did this too, but the valve itself is not working or adding anything to the mix (the valve is actually turning itself 'off' as the grid is doing nothing) - all you have is the SD-1 without any clipping. to get the valve to act as clipping diodes the grids need connected to their corresponding plates - you can hear that the valve is clipping when you do this.
Ok, just here to add a pic of my no-tone Valvecaster.
(http://s1.postimage.org/8ihqr.jpg) (http://www.postimage.org/image.php?v=gx8ihqr) (http://s2.postimage.org/3TfOA.jpg) (http://www.postimage.org/image.php?v=Ts3TfOA)
Many thanks to Adriano a.k.a. Renegadrian for direct support to a compatriot :icon_mrgreen:
I had only the time to try it in a Little Fender Frontman 15R but the improvement in sound is stunning: adds really a warm valve tone, even to a thinly suonding 8" solid state practice amp, looking forward to try it with the Lionheart and also with bass in my solid state Mark Bass rig!
FANTASTIC! I use it too on bass with great results, gives me a lot of "air"!
Hi people!!!
I'm new here. I've built a valvecaster a few months ago, and now I'm going to build another, but maybe this one without the tone pot. But... what I want to know is, if I remove it, how would it sound? as if it is with the tone pot set to max, min or...? I know that the pot doesn't make a lot of difference, but if there is someone that could help me... sorry for my English!!! and thank you!!! I'll post pics when I finish the new one!!
Hello and WELCOME! Your english is quite good, at least this poor italian understood everything you wrote... :icon_wink:
I made my first one with the tone pot - as it just filter some highs to ground, the more you turn it CCW the more highs go to ground, so you have no high at all, at the same time the tone pot maxed is like nothing goes to ground.
So yes, no pot or pot at its max position is the same!
Pics are always appreciated!!!
Thanks Renegadrian!!! ;)
I've made a new valvecaster, this one without the tone control, it's great!
And I decided to make another and combine both in one pedal (like the twincaster). And I've put a minitoogle switch, so you can choose to use it as a valvecaster or as a twincaster. It works, it's a great crunchy overdrive! but when I turn the volume pot or the gain pot loud I can hear the radio! :icon_confused: wtf!!! that must be grounding problem, no?
I'll try to solder the grounds again...
And what about if I put a tone stack??? with 3 knobs for hi mids and low? would it improve the sound or...?
When I finish the enclosure I'll post pics!!!
Cool thread!
I've been trying out all the mods on breadboard and decided to build the twin caster. Here's my progress so far.
it's amazing what you can do with a handle, plexi glass and a couple of parts from an old washing machine...
(http://i115.photobucket.com/albums/n302/Rg505bk/P5160133.jpg)
(http://i115.photobucket.com/albums/n302/Rg505bk/P5160134.jpg)
As you can see I've not done any wiring yet, just the case. I think I'll use push-pull pots for gain switches and maybe for negative feedback.
Anyway a big thank you for all of you who have contributed to this thread, I'm off to heat my soldering iron ;)
Hi again!
I post here some pics of my valvecaster and my new twincaster, hope you like them!
(http://i50.tinypic.com/2ymdab4.jpg)
(http://i49.tinypic.com/fbb8dt.jpg)
(http://i46.tinypic.com/2yvthjl.jpg)
(http://i48.tinypic.com/2rxe3bk.jpg)
(http://i46.tinypic.com/2yv1hlj.jpg)
I've put the voltage filter and regulator inside the twincaster, but when I turn the gain and volume loud there's still some little radio interferences... maybe I try with another caps... or just resolder everything again and a bit more clean :)
I just finished a build using a RCA 12at7 for the tube. I find it doesn't get too gritty at all, and only begins to break up with the gain is turned 1/2 way or more. It sounds pretty transparent actually. I was expected it to be pretty dirty. Now I just have to house this sucker. I wish I had cleaned the pins before soldering everything on there though, as they were pretty dirty and solder doesn't take to them. But I didn't feel like buying a socket, as the whole point of the build for me was that I already had all the necessary parts.
Iv had this done for awhile so heres some pics.
(http://farm5.static.flickr.com/4006/4578261903_57c6c3d682_b.jpg)
(http://farm5.static.flickr.com/4033/4578263075_770959517b_b.jpg)
(http://farm5.static.flickr.com/4049/4578264397_af035ded51_b.jpg)
Just need some paint. Thanks to everyone that helped.
I've browsed quite a few pages in this thread and am pretty interested in building one of these. I love simplicity.
I've got a couple of questions though, the answer might be in here somewhere, but 85 pages is a LOT. And I'm a ToobNoob
So here goes:
as every single tube is a little different, would/could/should you bias the tube for optimum performance and are the component values just starting points? Which components would do the biassing?
- I understand the heaters need 12V, and I have seen it mentioned that some have put voltages way over that on the anodes, using charge pumps. What effect does this have and should component (ratings) be adjusted for this?
- How to best power the effect? It eats through batteries, a One Spot is only 9V, PP2 'only' supplies about 200mA at 12V (which as I understand is barely enough). Not very keen on using a separate power supply for just that one tube pedal.
- is there a single document available that summarizes the whole bunch, including mods 'n stuff?
I also just stumbled across this thread and wondered if there were any other resources to help a pedal noob put one of these together. Any parts lists or kits based on this?
How similar is this to The Persuader - http://www.amplifiedparts.com/products/accessories/K-930 (http://www.amplifiedparts.com/products/accessories/K-930)
Hello guitarfly, I guess you should put enough effort and read the topic and search for the various layouts in the gallery, you have plenty of info just searching!!!
I have seen the Persuader, I know it has got an IC inside, maybe a 4558?! So it's not that similar to the Valvy, but I guess more to other tube pedals driven by an IC. Personally I don't like them, but hey they can give a good sound (altough not PURE tube...) No need to buy a damned overpriced Persuader kit, and for the Valvy there are no kits, just some regular components you can get at the local store...
Hey - just finished my very first project... Matsumin. I am having some trouble. Worked great out of the aluminum project box. Mounted everything inside OK. 9V power plug is neg tip and pos ring... right? When I mount the plug it is grounding out via the box. Now nothing works. What I am missing? Sorry if this is sounds dumb or is simple. Could use the help. Thanks
Did you use a metal power socket ?? If so, you need a plastic one. A really simple mistake which I've made myself.
yes, metal. yes, simple mistake. took it out of the box and it works great. looking for a plastic power plug now. thanks for the heads up. cheers!
I just tried building pedal using this layout http://s47.photobucket.com/albums/f191/krinor/?action=view¤t=Valvecasternylayoutmkabler.jpg
Im having trouble, its not working so I got my multimeter out and noticed that everything after the footswitch has a negative voltage, for example pin 5 on the valve socket has a heater voltage of -5v. What is the problem? Is something wired back to front?
Hello and welcome!
Krinor layout shows that pin 5 is connected to 12V and pin 4 is ground, so 0V.
check the power supply and its wiring!!!
Hi Fellows,
I've decided to start up a parts list for my first Valvecaster. I've tried my best to skim through this insanely large thread for some of this info, but I realized it might be easier to just ask.
I want to build a no-tone Valvecaster for bass guitar. I'm not looking for a ton of gain, and I'm not looking to color the tone too much. I just want a little wooliness to move a little more air through my solid state rig.
My question is, where should I start with voicing it for bass? I'm assuming I should socket the input and output caps and try experimenting with .1uf cap up front and then go from there.
Any other suggestions?
Thanks!
I used mine with bass, it's stock and I like the sound it gives out, more "air" but stays quite neutral.
You can find some layouts and parts lists in my gallery.
So, this weekend I summoned up the courage to start reading through this thread from start to finish. Thanks to everyone who has contributed to this great little project.
Below are my results. Not yet boxed as I'm too busy playing.
(http://www.sundgist.talktalk.net/Layout/-misc-/Valvy-1.jpg)
(http://www.sundgist.talktalk.net/Layout/-misc-/Valvy-2.jpg)
(http://www.sundgist.talktalk.net/Layout/-misc-/Valvy-3.jpg)
(http://www.sundgist.talktalk.net/Layout/-misc-/Valvy-4.jpg)
Trimmers are used for the plate resitors and everything else is socketed to play around with different values.
Valve is 12at7, running on 21v. Tried with 12ax7, some good sounds in there but found 12at7 more usable.
I've used 100k for the Gain pot for a good helping of dirt.
R1 = 470k
R2 = trimmer at 100k 'ish
R3 = trimmer at 100k 'ish
R4 = 220k
C1 = 33nF
C2 = 22nF
C3 = 1uF
Here is the perf layout I made (my first) to enable the valve to sit within the enclosure but viewable through a cutout between the knobs. Could be better laid out but was changed a few times during building.
(http://www.sundgist.talktalk.net/Layout/Valvecaster/Valvecaster%20test%20perf.gif)
and a vero layout for the 12.6v Heater regulator.
(http://www.sundgist.talktalk.net/Layout/Valvecaster/Valve%20Heater%20PS.gif)
Added orange led eye candy, not shown on layout.
Sound goes from clean boost (which can be driven harder with a clean booster or tube screamer type thing) through to Overdrive (which when driven harder gives a nice fuzzy compression).
I've been using this with a very ordinary clean solid state amp and it makes it sound quite impressive. I'm quite enjoying myself with this.
It appears that I am late to the party.
I've worked with a lot of solid state electronics before, but have yet to do anything with tubes. I've decided to dive in head first, reading as much as possible, and I think I'm ready to start my first build. I've worked up a simple design: three cascading valvecasters with separate gain controls, master volume, and a plate voltage variable from 9-12V (using an adjustable voltage regulator) and a fixed heater voltage of 12V. I plan to power it with an 18V 1A dunlop wart.
Schematic:
(http://i326.photobucket.com/albums/k433/om617/TripleThreat2010-06-21.png?t=1277428978)
Thoughts? Right now I'm on a (very lengthy) TAD away from my usual tools, but I should be able to scrounge up a cheap soldering iron to fabricate an enclosure-less circuit.
hey everyone,
i'm new around these parts, i have built a number of amps from scratch, i have never built a pedal though. i'm also quite terrible at reading schematics..... and wiring switches is the worst.
i have seen all the layouts for this pedal using a 3pdt switch for the led and bypass, but has anyone acheived this with a dpdt? and is there a layout for this aroud here? the reason i ask is that i have all the parts around here to build a few of these pedals to muck around with, but i only have dpdt switches left over from some other projects and dont want to go out and buy more stuff if i dont need to.
layout anyone?
thanks in advance.
Quote from: kylegood on June 27, 2010, 02:27:13 PM
i have seen all the layouts for this pedal using a 3pdt switch for the led and bypass, but has anyone acheived this with a dpdt? and is there a layout for this aroud here? the reason i ask is that i have all the parts around here to build a few of these pedals to muck around with, but i only have dpdt switches left over from some other projects and dont want to go out and buy more stuff if i dont need to.
layout anyone?
thanks in advance.
Hi there and welcome aboard!
Actually, the use of 3pdt or dpdt is common to all pedals, I use dpdt in valvies but in all the other pedal as well, it's not something related to a specific circuit but a common way to wire things up (so the method I use is applied to all pedals).
A lot of layouts are available, just go the the gallery and search for them, or other sites like geofex...
alright im back for some help now.....
i have built the pedal, its running sort of.... i have checked and double check and rewired.... and built a whole new pedal from new parts twice with the same result..
i have a lot of hum... and muddy muddy bass. i gan here the tube faintly through the bass and hum... but its just bass..
does anyone have any suggestions?? do the back of the pots need to be grounded??? i'm spent hours de bugging.... with no luck... the bypass and led and everything for that matter are functioning properly... but i just cant figure it out.
i used krinors layout as posted at the top of this page.
so my only two thoughts are the 1uf caps polarity is incorrect, or the back of the pots need to be grounded. or both
anyone have any suggestions?
thanks in advance.
So you have the 3 knobs version?! Guess you should check the tone pot wiring then.
Quote from: kylegood on June 29, 2010, 03:32:00 AM
alright im back for some help now.....
i have built the pedal, its running sort of.... i have checked and double check and rewired.... and built a whole new pedal from new parts twice with the same result..
i have a lot of hum... and muddy muddy bass. i gan here the tube faintly through the bass and hum... but its just bass..
does anyone have any suggestions?? do the back of the pots need to be grounded??? i'm spent hours de bugging.... with no luck... the bypass and led and everything for that matter are functioning properly... but i just cant figure it out.
i used krinors layout as posted at the top of this page.
so my only two thoughts are the 1uf caps polarity is incorrect, or the back of the pots need to be grounded. or both
anyone have any suggestions?
thanks in advance.
I build using that layout too.
Are you running at 9 or 12 volts? Are you using a DC wall jack(wall wart)? If so the hum could be coming from the wall wart being "Unregulated" which means it could be sending in hum from your AC jack. The best thing you can do to kill the hum is to regulate the power. Ill explain here in a sec...
To kill the muddyness i HIGHLY recommend running at 12 volts, it REALLY makes the sound MUCH better, jus 3 more volts makes it ALOT better. And if the sound is too bassy for you, you can change one of the capacitors(C1) to a lower value, maybe .022uF, that will lower the bass to a nice level. If you want, you can increase the gain of the pedal by adding a higher value potentiometer. Change it from B50K to idk, maybe even A1M! 1M audio. That will really up the gain, but it may be too much for your liking, so you can always experiment if u have the money for more pots an stuff. P.S. if ur on a budget do NOT go to radioshack...
As for the hum. You can try this: buy a 7812 Voltage regulator, they are pretty small, an u can get them from radioshack for pretty cheap(but way cheaper online, try Mouser.com), and a 1000uF Capacitor(Electrolytic). I have a diagram from our friend Renegadrian that shows you how to do this, i can post it here for you(With his kind permission of course) and it will show you how to do this. Its pretty simple. Then after you put that in, run the pedal at 18 Volt(if u cant, atleast make it higher then 12 volts.) and play! You will notice a HUGE difference i guarantee it. I just installed my regulator a few days ago an i dont know why i didnt when i first built this pedal xD
If you wana try the regulator, let me know an i will be here to asssit you as best as i can :icon_mrgreen:
This layout is in my gallery, so it's there for everyone to use - no permissions needed.
(http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=39755&g2_serialNumber=1)
Quote from: Renegadrian on June 29, 2010, 11:16:05 AM
This layout is in my gallery, so it's there for everyone to use - no permissions needed.[/img]
Ya thats it. That should show you how to do it. If u need some help we are here :icon_biggrin:
i have got it running. and it sounds amazing.... the 12volts really helped.
question... how terrible would it be to run this on 18 volts?
Quote from: jaki54321 on June 29, 2010, 11:08:46 AM
If you want, you can increase the gain of the pedal by adding a higher value potentiometer. Change it from B50K to idk, maybe even A1M! 1M audio.
That won't increase the gain. Rather it will make for a cleaner boost. 1M is far too high though. 100k would be fine. But neither will increase the gain. Though a cathode bypass cap might.
the gain it has is great, i'm not worried about that... just for kicks i ran it on 18 volts, and it seemed that it was alot clearer... more defined maybe is the words..... i just want to know if its safe...
Keep in mind that the heaters must always receive 12V. You can go from 12 to 300+ at the plates (pins 1 and 6) but the heaters run always at 12V. Running them at higher voltages will lead to permanent damage of the tube itself.
Quote from: kylegood on June 29, 2010, 03:27:06 PM
the gain it has is great, i'm not worried about that... just for kicks i ran it on 18 volts, and it seemed that it was alot clearer... more defined maybe is the words..... i just want to know if its safe...
if you have a 7812 volt regulator installed, running at 18 volts will be perfectly safe. If you run at 18 with the 7812 regulator, it will drop the voltage down to 12 volts, which will allow you to run at 18 volts. I personally recommend 18 ONLY if you have that regulator and the capacitor installed. However that 7812 regulator may get pretty hot. I mounted mine on the side of my enclosure which seems to keep it cooler. You can also put a heat sink on it
Quote from: frequencycentral on June 29, 2010, 03:13:24 PM
Quote from: jaki54321 on June 29, 2010, 11:08:46 AM
If you want, you can increase the gain of the pedal by adding a higher value potentiometer. Change it from B50K to idk, maybe even A1M! 1M audio.
That won't increase the gain. Rather it will make for a cleaner boost. 1M is far too high though. 100k would be fine. But neither will increase the gain. Though a cathode bypass cap might.
Really? I always heard it will up the gain... hmm... maybe ill give the 100K pot a try. is it worth it?
Quote from: jaki54321 on June 29, 2010, 05:32:53 PM
Quote from: frequencycentral on June 29, 2010, 03:13:24 PM
Quote from: jaki54321 on June 29, 2010, 11:08:46 AM
If you want, you can increase the gain of the pedal by adding a higher value potentiometer. Change it from B50K to idk, maybe even A1M! 1M audio.
That won't increase the gain. Rather it will make for a cleaner boost. 1M is far too high though. 100k would be fine. But neither will increase the gain. Though a cathode bypass cap might.
Really? I always heard it will up the gain... hmm... maybe ill give the 100K pot a try. is it worth it?
http://www.diystompboxes.com/pedals/tubedummy.html
"The cathode resistor along with the Plate resistor control the gain of the tube stage. Typical values are anywhere from 100 ohms to 10K. Smaller values = more gain."A 100k gain pot will allow for cleaner boost, well worth it.
I assumed the same when I used 100k for gain.
Turns out that max gain is when the pot is at least resistance. Mine seemed to be clean for half the pots travel.
Instead of changing the pot I've put a 82k resistor in parallel with it, making 47k. This gives me clean with a fair bit of headroom and also gives a bit of antilog taper which spreads the gain out a bit.
There's quite a range of gain in the last bit of the pots travel. If I need more clean headroom I can always switch a 47k resistor in series.
Quote from: frequencycentral on June 29, 2010, 05:42:19 PM
Quote from: jaki54321 on June 29, 2010, 05:32:53 PM
Quote from: frequencycentral on June 29, 2010, 03:13:24 PM
Quote from: jaki54321 on June 29, 2010, 11:08:46 AM
If you want, you can increase the gain of the pedal by adding a higher value potentiometer. Change it from B50K to idk, maybe even A1M! 1M audio.
That won't increase the gain. Rather it will make for a cleaner boost. 1M is far too high though. 100k would be fine. But neither will increase the gain. Though a cathode bypass cap might.
Really? I always heard it will up the gain... hmm... maybe ill give the 100K pot a try. is it worth it?
http://www.diystompboxes.com/pedals/tubedummy.html
"The cathode resistor along with the Plate resistor control the gain of the tube stage. Typical values are anywhere from 100 ohms to 10K. Smaller values = more gain."
A 100k gain pot will allow for cleaner boost, well worth it.
So... Small Value puts more gain? I like the way my valvecaster sounds right now but Im not afraid to experiment... I also thought if you lowered the input cap(C1) it will reduce bass, one person put it down to .022uF and said he loved it. Any suggestions on tonal improvements? lol
all hail vavlecaster. so i used xicon caps in mine that r 630v . im runnin a 12ax7 in it and luve it . renagadrian mentioned he tried it but to bassy . with a 12au7 ,it was nothin but clean . soooo would the 630v caps have a say on drive and gain?
Quote from: ultran8 on July 03, 2010, 05:09:01 PM
soooo would the 630v caps have a say on drive and gain?
I had a 12ax7 in mine sounding good with the stock values. Went for slightly lower gain 12at7 in the end (sounded better to my ears at full gain).
I doubt the voltage rating of the caps would have any influence.
I lowered the input cap to 10nF and the one between the triodes to 22nF to take some bass away. Depends on taste, amp, valve(maybe?).
Hi everyone
i'm total noob and this was my first attempt to build stompbox in sum i failed :icon_eek: . I'm getting no sound just buzz was hoping for some hints were did i get wrong.
Used this schematics without switch
(http://i360.photobucket.com/albums/oo41/regnad/Valvecasternylayoutmkabler.jpg)
With 9v 1A adaptor
only difference is that the tube is soviet 6N1P(perhaps that's the problem?) checked connections several times everything seems ok
Voltages for pins are as follows
1: 3,2
2: 1,2
3: 0
4: 0,1
5: 8,8
6: 6,2
7: 6,2
8, 0
if necessary i can post some pics
sorry for bad english
P.S. will try to make another one with tube 6N2P(12AX7 equivalent)
Quote from: Kazha on July 04, 2010, 11:01:57 AM
Hi everyone
i'm total noob and this was my first attempt to build stompbox in sum i failed :icon_eek: . I'm getting no sound just buzz was hoping for some hints were did i get wrong.
Used this schematics without switch
(http://i360.photobucket.com/albums/oo41/regnad/Valvecasternylayoutmkabler.jpg)
With 9v 1A adaptor
only difference is that the tube is soviet 6N1P(perhaps that's the problem?) checked connections several times everything seems ok
Voltages for pins are as follows
1: 3,2
2: 1,2
3: 0
4: 0,1
5: 8,8
6: 6,2
7: 6,2
8, 0
if necessary i can post some pics
sorry for bad english
P.S. will try to make another one with tube 6N2P(12AX7 equivalent)
Whoa man... Ok i looked up some data on a 6N1P tube and um it says it runs on 6.3 volts! idk if this data is correct but it is, i think your putting too much voltage in the tube. I am no professional, but I think thats y it may not be working.
Try a 12AU7, 12AT7, or 12AX7, jus about any tube that can run on atleast 9 volts will be ok, take a look at these data sheets, jus open them up an look at the voltage requirements/limits.
http://www.drtube.com/tubedata.htm
Every tube will sound different, not jus by type, but by company as well, try Eurotubes.com
can't buy them enywhere localy so went for soviet tubes
will have to order some 12AU7 todey from ebay then
thanks jaki :) just have to wait now
Quote from: Kazha on July 05, 2010, 02:16:04 AM
can't buy them enywhere localy so went for soviet tubes
will have to order some 12AU7 todey from ebay then
thanks jaki :) just have to wait now
ok. also did you build this layout without the switch?
Quote from: jaki54321 on July 05, 2010, 03:45:07 PM
Quote from: Kazha on July 05, 2010, 02:16:04 AM
can't buy them enywhere localy so went for soviet tubes
will have to order some 12AU7 todey from ebay then
thanks jaki :) just have to wait now
ok. also did you build this layout without the switch?
Yes without (don't have it jet) did that just to test if everything is ok
cos i had some concerns about the tubes and they came true :(
don't know what to do with them now though :-\ , but they came very cheap and theres probably some project out there,
where i could put them in, in future.
in few days 12AU7 will be in my hands and ill wrap it up ;)
One thing to keep in mind about the 6n1p and similar types is that heater wiring is different - different pin out and different voltages. It is a true 6v (6.3v really) tube not a 12v tube like the 12--7s that can be run at 6v (parallel). Pin 9 on the 6n1p isn't even used - it goes to a shield that is between the 2 triode sections. So if you want to use them, you may need to rewire the heaters and probably drop the voltage down to the 6.3v or so - at least under 7v. I don't have the spec sheets in front of me so I'm writing this from memory. I'll look at the schematic you posted.
Ok - Just looked at the schematic, apparently you aren't using pin 9 at all so that's cool. You are running 5 at +8.8 v so that is too high. You might try re-wiring it so that R3 hangs off pin 5 with 9v coming in and just jumper pin 5 to 6 - that way both will get 6.2v. Pin 4 is ground so that's ok.
Should work - hope this is of some help -
Jim
Quote from: Kazha on July 05, 2010, 07:03:35 PM
Quote from: jaki54321 on July 05, 2010, 03:45:07 PM
Quote from: Kazha on July 05, 2010, 02:16:04 AM
can't buy them enywhere localy so went for soviet tubes
will have to order some 12AU7 todey from ebay then
thanks jaki :) just have to wait now
ok. also did you build this layout without the switch?
Yes without (don't have it jet) did that just to test if everything is ok
cos i had some concerns about the tubes and they came true :(
don't know what to do with them now though :-\ , but they came very cheap and theres probably some project out there,
where i could put them in, in future.
in few days 12AU7 will be in my hands and ill wrap it up ;)
Thats good. Spud is probably right. Im not a pro but you can give his idea a try. it may jus work...
Quote from: spud on July 06, 2010, 03:46:58 PM
One thing to keep in mind about the 6n1p and similar types is that heater wiring is different - different pin out and different voltages. It is a true 6v (6.3v really) tube not a 12v tube like the 12--7s that can be run at 6v (parallel). Pin 9 on the 6n1p isn't even used - it goes to a shield that is between the 2 triode sections. So if you want to use them, you may need to rewire the heaters and probably drop the voltage down to the 6.3v or so - at least under 7v. I don't have the spec sheets in front of me so I'm writing this from memory. I'll look at the schematic you posted.
Ok - Just looked at the schematic, apparently you aren't using pin 9 at all so that's cool. You are running 5 at +8.8 v so that is too high. You might try re-wiring it so that R3 hangs off pin 5 with 9v coming in and just jumper pin 5 to 6 - that way both will get 6.2v. Pin 4 is ground so that's ok.
Should work - hope this is of some help -
Jim
Thanks for an idea but nothing happens tube isn't even lightening up or getting hotter ??? voltage goes down to 0 at the moment when it is connected to pin 5 :icon_neutral:
Quote from: Kazha on July 07, 2010, 07:51:02 PM
Quote from: spud on July 06, 2010, 03:46:58 PM
One thing to keep in mind about the 6n1p and similar types is that heater wiring is different - different pin out and different voltages. It is a true 6v (6.3v really) tube not a 12v tube like the 12--7s that can be run at 6v (parallel). Pin 9 on the 6n1p isn't even used - it goes to a shield that is between the 2 triode sections. So if you want to use them, you may need to rewire the heaters and probably drop the voltage down to the 6.3v or so - at least under 7v. I don't have the spec sheets in front of me so I'm writing this from memory. I'll look at the schematic you posted.
Ok - Just looked at the schematic, apparently you aren't using pin 9 at all so that's cool. You are running 5 at +8.8 v so that is too high. You might try re-wiring it so that R3 hangs off pin 5 with 9v coming in and just jumper pin 5 to 6 - that way both will get 6.2v. Pin 4 is ground so that's ok.
Should work - hope this is of some help -
Jim
Thanks for an idea but nothing happens tube isn't even lightening up or getting hotter ??? voltage goes down to 0 at the moment when it is connected to pin 5 :icon_neutral:
Id jus wait for the 12AU7 and give it a try. Oh since you did wire the pedal without the switch, make sure it is connected like this:
(http://www.beavisaudio.com/Projects/ValveCaster/MatsuminValveCasterWiring.gif)
i think this is one sheet u did follow tho
Received tube today, not much to say my clumsiness made my day really bad i broke it :icon_cry:
at least finished up proco rat that worked
probably gonna try to figure out how to make it work with 6n1p if anyone has some more ideas i would kindly appreciate it :(
So I built the a box based on the schematic I posted earlier. I left out the "warmth" control for now just because I figured it was ambitious enough building a circuit with 3 dual triodes for my first valve circuit.
First impressions on the sound are: UNBELIEVABLE. Playing it through the clean channel on my Egnater Rebel it sounds like a cranked Laney stack... totally awesome.
The only problem is a persistent high-pitched whine/hum. I messed around with my grounding scheme to no avail, so I figure it must be the caps ringing or some behavior of the 12AU7s that I am not aware of. Has anyone had similar problems and/or have any ideas?
Quote from: Kazha on July 09, 2010, 06:44:10 PM
Received tube today, not much to say my clumsiness made my day really bad i broke it :icon_cry:
at least finished up proco rat that worked
probably gonna try to figure out how to make it work with 6n1p if anyone has some more ideas i would kindly appreciate it :(
Oh no! I am soo sorry that happened to you! Im clumsy too so i kno how it feels to break a tube, i buried mine in my backyard and it grew more tubes(Sarcasm lol)
I looked over the datasheets. I think what you should do is get a 6v DC wall wart and have it run the same way as u have the connections now.
have pin 5 running to the positive rail of the DC jack and pin 4 to ground. Use the sleeve of the input jack as ground. if it still doesnt work, have pin 4 run to positive and pin 5 to ground. If it still doesnt work let me kno an ill see if i can come up with something.
Everything works now :icon_mrgreen: re soldered everything and took 6v DC sound thou isn't good (cos of tube probably) and there is no boost actually clean is louder :D why that is I don't know same thing is on proco rat ??? But I'm happy that it works :) gonna find cool knobs and post some pics when i'll have a time
P.S. Thanks for help ;)
I've just added the vibracaster tremolo to my build. A worthy addition to anyones valvecaster.
Here's a verified stripboard layout for just the addon LFO.
(http://www.sundgist.talktalk.net/Layout/Valvecaster/ValveTremAdd.gif)
8k2 resistor should be changed to 47k if yours runs on 12v. Mine is at 21v and I've used 27k here. Changes the range of tremolocity. :icon_rolleyes:
Full post here including flashing rate LED. http://www.diystompboxes.com/smfforum/index.php?topic=70160.msg718098#msg718098 (http://www.diystompboxes.com/smfforum/index.php?topic=70160.msg718098#msg718098)
Re: Tube boost + overdrive running off a 9 volt battery
« Reply #1734 on: July 11, 2010, 02:23:15 PM »
--------------------------------------------------------------------------------
So I built the a box based on the schematic I posted earlier. I left out the "warmth" control for now just because I figured it was ambitious enough building a circuit with 3 dual triodes for my first valve circuit.
First impressions on the sound are: UNBELIEVABLE. Playing it through the clean channel on my Egnater Rebel it sounds like a cranked Laney stack... totally awesome.
The only problem is a persistent high-pitched whine/hum. I messed around with my grounding scheme to no avail, so I figure it must be the caps ringing or some behavior of the 12AU7s that I am not aware of. Has anyone had similar problems and/or have any ideas?
sounds like a layout issue..picking up rf or not using sheilded wire in the signal path. Also running a pedal with a buffer in front of it helps with the whine. I have built a bunch of these three tube versions and the only one that doesnt whine as much is the one i built in a huge enclosure. Try putting a buffered chorus in front of it. it doesnt have to be turned on even. hope this helps. cheers, Zambo
Hi,
I have a question that I'm hoping somebody can help me out with (probably Renegadrian). So, here's my question: based on the circuit below, in theory, do I need to run the ground from the input sleeve via individual wires to tube pin 4, volume 1, and 3pdt 5, or can I just instead run a single wire from the input sleeve to, say 3pdt 5, then from there to volume 1, then to tube pin 4 and have it do the same thing? I'm building a single enclosure with three vlavecasters in it with a fourth master 3pdt on/off, and I'd really save me a lot of wire mess if I can just do the grounding like this instead of running a separate wire out to each solder point from the input sleeve. Thanks for the help in advance. =]
-Jr
Quote from: Kazha on July 04, 2010, 11:01:57 AM
(http://i360.photobucket.com/albums/oo41/regnad/Valvecasternylayoutmkabler.jpg)
Both methods should work fine, I am using the second one ATM when more complex pedals are made...I take a thicker wire, strip it and use it as a ground bus, as you can find on some PTP tube amps. Then I solder it between in and out and solder everything in between on it.
Ooo... that's a great idea too! Thanks for the help. =] I'll post my results when I finally get this thing done.
Hello all has anyone thought of using this circuit as an output section in some sort of compressor? Such as taking the envelope section of say the Clari not or something more sophisticated and then combining it with the boost section?
nope - you could be a pioneer! Just try! :icon_wink:
I too have been using the ground bus wire between in and out jacks. Much cleaner and easier. I have been building little amps similar to Frequency Centrals.Mine is actualy just the power section of the firefly and a valvecaster pre running at 200 volts. If you build one of those and put the triple caster in front it is incredible.Am just now learning how to run power tubes in push pull paralel.
Hows the pedal coming along Mcgrath?
It's coming along nicely. I just have to finish up the grounding, install the power wiring, then figure out how to get my LED's to stay at the bottom of my tube sockets (just had the novel idea to try hot glue), and I'll be ready to fire it up for some triple valve mayhem! I need to get it done in the next week since I'll have no time whatsoever after starting grad school on the 23rd. =P
Quote from: zambo on August 12, 2010, 01:15:17 AM
I too have been using the ground bus wire between in and out jacks. Much cleaner and easier. I have been building little amps similar to Frequency Centrals.Mine is actualy just the power section of the firefly and a valvecaster pre running at 200 volts. If you build one of those and put the triple caster in front it is incredible.Am just now learning how to run power tubes in push pull paralel.
Hows the pedal coming along Mcgrath?
post a clip when you get it done! Good luck and get busy! :icon_mrgreen:
Alrighty... I got it done! Worked first time I plugged it in! Ran at 9 volts just great! Wanted to try it at a full 12. Plugged in a wart that I thought was negative tipped. Turned out it wasn't. Fried something. Smells bad. Who wants to be the first at chiming on on what it was that I fried? I'm using Renegadrain's layout with the 7812 limiter and the 100 uf cap for power, so I'm figuring it's one of those two items that's stinking up my living room like melted plastic.
For good measure though, here's the inside and outside (minus knobs) pics. I'll put fun lit up ones once we all figure out what I fried and I get it back up and running. =]
(http://jrmcgrath.com/images/IMG_7571.JPG)
(http://jrmcgrath.com/images/IMG_7572.JPG)
well, my first guess is the 7812 and the cap on the power input if you used that. Did you put a 100uf cap from + to - on the dc in? I got my money on those two items first. imho the difference between 9 and 12 isnt all that much on this. If you are going to run a higher voltage that 9 make a multiplier and take it up to like 24 or 36. they get better mids i think. That thing looks awesome man! Nice choice of enclosures!
How much do the tubes glow in these circuits? Without an LED behind them, of course...:icon_biggrin:
As in a standard Valvy, I guess it depends on the tube used - some glow more, some are barely lit...
Hi guys!
I just started to play with tubes and tried the valvecaster. Unfortunately, it does not work. Please help...
The caster adds gain, but takes much of the loudness.
I used (http://a.imageshack.us/img155/3599/valvecasterv05qs5.jpg) this layout, but did not put the volume and not the tone pot. So I also did not put C4 cap. Just wired from C3 directly to S1.
I also did not have a 50k B pot, so I put a 100k B pot instead.
I am running a 12AU7 (ECC82) with a 9v, 500mA supply.
Again the problem: The gain knob works, I get a sound out of it, but way to silent...
Any idea, where there could be the mistake?
Thanks, I really appreciate!
Dongle
EDIT: Sorry, image did not work... How do I do it?
EDIT 2: No I made it... Hope, you can help me!
Regards
Hello and welcome aboard!
Glad you used my layout - so you went straight from C3 to output (this cap can be polarized or NP)
It should work good, as long as there are no other variations and no soldering errors, bridges, whatsoever...
Only thing, did you try it a 12V?! I never did, some reported it works good at 9V but I always suggest 12V. 500 mA should be enough. the 100k pot should fit the circuit without too much change...
Check your board and see if everything's all right...
Thanks for your reply!
You run it on 12V? Your layout said 9, thats why I used it...
Is 500mA also enough if I run on 9 v or only for twelve? Do I have to adapt the circuit for 9 V?
And one last question: How can I check the circuit / which voltages should I post, that you can tell me, what might be wrong? My visual control could not find any mistakes...
I used a polarized cap for C3 and put the minus to the side of the output.. I guess, that should be fine...
Yes I always use 12V. The layouts I did back then were from the original schem, which calls for 9V.
Basically, you can also apply more than 12V to the plates (pin 1 and 6) while 4 and 5 HAVE TO be ground and 12V.
(9V is fine but you give the heater less than required)
There is nothing to adapt when using one voltage or another, and yes 500mA should be fine with both voltages.
Also, if you wired C3 like THIS LAYOUT (http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=42416&g2_serialNumber=2) it's ok.
voltages were posted several pages back from other users. check em out!
Hi Renegadrian!
I tried to check the voltages, but the mearsurement device is broken... I will get a new one tomorrow and post again...
Is there a possibilitiy to check if the valve is working correctly? I still think, that my circuit is correct. But still I get only a weak signal out of it. ther might be a problem with the 12AU7...
You should get another tube then!!! ;D
Well, did you break the line under C1 (e3)?!
hey everyone, first time posting. i had a question about this valvecaster pedal. is there a parts listing for this thing anywhere? thanks in advance for the help.
Are you sure you read the thread^!? :icon_eek: Or took a look in the gallery?! :icon_eek:
Quote from: Renegadrian on August 15, 2010, 06:45:11 PM
You should get another tube then!!! ;D
Well, did you break the line under C1 (e3)?!
Alright... I will get another tubes. Will take some days, but probably its the only way...
Yes, I broke the line under C1.
Hey Renegadrian: Thanks a lot for being so helpful! I will try some thing in the next day and report my experience than. Don't have time to solder today, but the next days...
Thanks and regards!
Dongle
Quote from: Renegadrian on August 14, 2010, 06:33:19 AM
As in a standard Valvy, I guess it depends on the tube used - some glow more, some are barely lit...
Hm, interesting. Which one would you recommend for max glow?
I would feel like a cheater to have it glow using an LED. :p:
@Dongle
Glad if I can help you somehow! go on debugging that $hit and report back! I's gonna work!!!
@azrael
Actually I sperimented several tubes, most NOS. I don't remember which kind or brand were the brightest, sorry...
Dude Renegadrian you are like the patron saint of valvecaster building...lol. Your help is definatley cool bro! Thanks .
:icon_lol: :icon_redface: :icon_wink:
Quote from: Renegadrian on April 29, 2009, 04:09:27 PM
I went to the reharsal yesterday, First time with this band, playing QUEENSRYCHE songs - me on the bass - I took my Valvy with me...Man, it's so good on bass...It just rounds up the sound to achieve the Eddie Jackson (bass god for me...) sound...
Just wanted to share this experience...
Hey there,
I'm going to attempt a Valvecaster, and I've been reading over the megathread. Sorry if I missed this somewhere, but are there any mods needed to the basic Valvecaster layout to make it suitable for bass guitar? I'm pretty excited about you getting the Eddie J sound, as he's a god to me as well! My plan is to use a 12au7 (I think I have one around somewhere), and try it at both 9v and 12v. Later I'd like to build a 9au7 version and a subcaster.
Also, to use the 7812 regulator at 12v, is 18v too much? The reason I ask is that I have an 18v charge pump adapter for my Power All.
IT IS FINISHED! I've finished the triple valvecaster I've been working on. It's just three valvecasters housed in a single enclosure with a master bypass switch so I can go from clean to any of the three stages of overdrive that the pedal houses. I have it running at 9V... I tried it at 12V, but for some reason with the power supply I have, it gives it some mad hum when you actually turn on a tube. I couldn't really tell a difference between it running at 9 or 12V anyway, so there ya go.
I have each tube set up to have the input cap at either .001uf or .022uf with a toggle, but I've been leaving at the .001 position for most things. The .022 adds a lot of bass, which can be fun sometimes, but not necessary for the way I play.
Here's a video of it on youtube: http://www.youtube.com/watch?v=AOLSZuZ0OS8 (http://www.youtube.com/watch?v=AOLSZuZ0OS8). I'm really happy with the way it came out sounding... I hope you like it too.
Lastly... I just wanted to give special thanks to Renegadrian and Zambo. You both have provided priceless guidance and encouragement through this board and your messages. Thanks so much!
Here's the final product lit up all fancy-like. The green is the lowest gain setting tube, blue is mid, and white is the highest gain setting. Also, here's a link to the layout I made to make the whole thing: http://jrmcgrath.com/images/triple%20valvecaster.jpg (http://jrmcgrath.com/images/triple%20valvecaster.jpg). It's kinda wonky and confusing, but it got the job done for me. I'd post the image here, but it's huge and I don't want to resize it.
(http://jrmcgrath.com/images/IMG_7589.JPG)
Sounds Sweet! Have you tried a 12at7 in the middle yet? Adds a lot more gain. run both blue tubes on .001 middle tube tone set 3/4 to the dark side. last tugbe on .022 cap. No rat needed. Awesome looking pedal!
I don't have an at7... if I get my hands on one, I'll schlap it in there and give it a whirl. Have you tried an ax7?
Quote from: karter2000 on August 17, 2010, 04:31:47 PM
Quote from: Renegadrian on April 29, 2009, 04:09:27 PM
I went to the reharsal yesterday, First time with this band, playing QUEENSRYCHE songs - me on the bass - I took my Valvy with me...Man, it's so good on bass...It just rounds up the sound to achieve the Eddie Jackson (bass god for me...) sound...
Just wanted to share this experience...
Hey there,
I'm going to attempt a Valvecaster, and I've been reading over the megathread. Sorry if I missed this somewhere, but are there any mods needed to the basic Valvecaster layout to make it suitable for bass guitar? I'm pretty excited about you getting the Eddie J sound, as he's a god to me as well! My plan is to use a 12au7 (I think I have one around somewhere), and try it at both 9v and 12v. Later I'd like to build a 9au7 version and a subcaster.
Also, to use the 7812 regulator at 12v, is 18v too much? The reason I ask is that I have an 18v charge pump adapter for my Power All.
If I remember well (I always post at 4am, sleeeepy...) you can sub the input and putput caps with some electros, the higher the value the more bass gees thru. I used the very first one I build which is a standard values, no tone.
I made one with a 9AU7, but that didn't impress me much, as Shania would say! :icon_smile:
18v should be quite good for the reg. - hook it and see if it gets too hot after a while, in that case you can screw it (in a good way!) (sorry, I'm with stupid!) to the enclosure or consider a small heatsink. Usually the screw it method works fine, but it's not always needed.
Please take a look at my band's site if you have some spare time...http://nuke.mindcrimeitaly.com/ and you'll find some vids too...Hope you'll enjoy the link!!!
Great videos! Are you using the Valvecaster in those?
Thanks for the help!
Yeah, I tried the ax7 but it was a little barky and harsh. Like some notes would just jump out louder and knife you in the face kind of loud and harsh. Not the cool kind you would think of. I tried about every ax au at ay config you could think of. au at au in that order seems to be the best. Older rca and conn tubes seem to be the smoothest and best sounding. If you drop your treble and bass and boost your mids it counter acts the space charge tendencies that are inherent with this design. Yuo will get a lot less fizzle. With one valvie it sounds grate, three starts to get fizzy. Rolling of one of the tones most of the way helps too. I have found that running it while my amp is on the drive channel but set really clean helps. Clean channels seem to have a built in mid scoop wich works against you sometimes....man i type to much.... :icon_redface: Nice pedal bro!!!
Quote from: karter2000 on August 17, 2010, 11:30:48 PM
Great videos! Are you using the Valvecaster in those?
Thanks for the help!
Thank you! Actually there's no Valvy in those videos, as it was lended to a friend at the time of the shooting - I used an Orange Squeezer instead.
Quote from: Renegadrian on August 18, 2010, 06:22:56 AM
Thank you! Actually there's no Valvy in those videos, as it was lended to a friend at the time of the shooting - I used an Orange Squeezer instead.
Great bass tone! You know, I built one of those but I never boxed it. It works great....maybe it's time to break it out again.
what about adding a cathode follower? negative feedback to increase gain?
uping the voltage seems to increase the gain a lot. especialy on twincasters etc. its easy as well. 36 volts gets pretty nasty. 12at7 at 63v gets real nasty.
12AT7...yum...See my TUBE STAR, it can be used with an AU, but the results I liked the best were with an AT, running at 50V.
Great sound!
yeah now we are talkin! Valvecaster is a super awesome first build, but its not the gain monster alot of people seem to want. At7 sounds toothy!!!
zambo, if you're after gain monsters you definitely have to check out my TUBE STAR, it really roars with the AT!!! Easy to build (not so different from a Valvy) but real fun for you, not so much for the neighbors!!! :icon_eek: :icon_twisted:
Nice to see the old tube thread still a-goin'. Haven't been around much, but Adriano, you are still the man. I need to dig my doubly valvy up and finish it off now that we are done moving around and settled. Yes, the valvecaster isn't a gain monster, but you can always feed it more volts!
I been building these http://www.youtube.com/watch?v=YtFdINnPEeo and http://www.youtube.com/watch?v=bw5zT8GpDpk tiny amps are way fun.. I am going to have to venture into the 15 watt zone though....... :o
Okay, I just breadboarded a basic Valvecaster (no tone) with a 12at7 (only one I had around). I have to say, this thing sounds excellent with bass guitar. Initially I tried it at 9v, but soon switched it to 12v (sounded better to me). Not lots overdrive, but a nice low-gain growl. Not sure if I need much more overdrive than it produces anyway. Definitely lots of volume available. Can't wait to try it with a 12au7.
Now I'm hooked! The tube I'm using is glowing quite bright...soooo cool!
Just want to say, that my valve caster is also working now. I think the problem was a broken cap...
Thank you Renegadrain for your help!
@Ripthorn
Nice to see you back, man! I love how this project still catches attention, and some newcomers are now in the topic.
You're definitely right about that!!!
@Karter2000
Yes, I do think that an AT7 in the Valvy gives that extra kick, and yeah it's good on bass!!! It "rounds" and fattens the tone in a "pure" way. Post pics when you're done with it, right?!
@Dongle
Nice to read you made it, man!!! Glad if I helped you somehow...Enjoy!!!
Totally tube noob question, but how do you guys mount the tube socket in the enclosure? I've looked through the thread, but I'm still confused. I'm using a chassis mount tube socket.
Thanks!
Quote from: karter2000 on August 20, 2010, 12:32:14 PM
Totally tube noob question, but how do you guys mount the tube socket in the enclosure? I've looked through the thread, but I'm still confused. I'm using a chassis mount tube socket.
Thanks!
Chassis mount sockets have a diamond-shaped plate around the socket with holes in the sides. You mount the socket using a nut and screw going through these holes and corresponding holes in the enclosure. You can see the screws in this pic beside the base of the tubes.
Quote from: jrmcgrath13 on August 17, 2010, 06:45:21 PM
(http://jrmcgrath.com/images/IMG_7589.JPG)
As I told you before, my valvacaster is working now - with 9 V and I like it!
But: Is there a possibility to get more volume? I guess, with 12 V it would be a bit louder, but is there also another possibility?
What would happen if I lower the 100k resistor R3 and the 220k resistor R2? I thought, I might get higher voltage at the Anodes -> more volume?! Is this true? What disadvanteges do I get, if I would do it?
I believe you will get more volume and clean headroom. If you go to the homepage and look at tube amp stuff > tubes for dummies you will find a lot of helpful stuff there. It explains all of the resistors and caps as well as cathode bypass caps and plate resistor bypass caps for rooling of highs lows etc. Very cool stuff and it has been invaluable for me. If you build pne of these then you will probably build two. Then you are going to want more gain etc. That page will help you a lot. And yes nore voltage = more volume in my experience ( wich isnt a lot ) :icon_wink:
I thought you'd all enjoy some Valvecaster pr0n - my 12AU7 running 12v, got it up and running very quickly after reading this entire topic. Cozy! (NB: It's a 1 minute exposure...)
(http://farm5.static.flickr.com/4106/4947767724_c2c7e87d0b.jpg) (http://www.flickr.com/photos/71172892@N00/4947767724/)
Glowing valve / tube (http://www.flickr.com/photos/71172892@N00/4947767724/) by Tom.Whitwell (http://www.flickr.com/people/71172892@N00/), on Flickr
I just found an old 12 V supply and will test it later this day... I am looking forward to it - especially, because I already like it with 9 v...
Wondering if anyone here can help me with this project... I built it on the bredboard and noticed that the status LED I put in turned off as soon as I made the connection between pin 5 and +12v. When testing the tube (-v to pin 4, +v to pin 5) with my multimeter connected to the bredboard I notice the voltage dips from 12.28v to 0.68v when the tube is connected (like a short). No glow. Tested 3 different tubes, all of which were working perfectly fine in my guitar amp. WTF am I doing wrong?
is pin 9 hooked up? if so un hook it...
did you use a schematic like renegadrians? If not try his. His stuff is pretty bulletproof ;)
No, like I said I was testing it only with pins 4 and 5. Nothing else was connected anywhere.
I tried with a different power adapter and it worked, I wonder why the hell the regulated one didn't.
Sounds like your supply is not strong enough or you have a "wrong connection" - sorry, dont know the english word.. maybe "short circuit"??
It LOOKS like a short, but the power supply works with everything else I plug it into. It's 12v, 1.5A, should be more than strong enough to power the valvecaster, no?
valvecaster will run on as little as 9v 200ma so yes. I believe heaters pull 150ma and plates are under 10ma
Just wanted to say that I built my first one yesterday, rock'n'roll. Thank you everybody for this super thread.
Hi folks, 1st post.... 1st problem!!!! Just built this box, 1st attempt at any such venture! It does work but there is a loud hum from it, which increases dramatically with volume... I've checked and everything looks ok but obviously I've boobed somewhere.... any suggestions?
john
www.oneeyedog.co.uk
Try a different power supply. They will cause a mean hum! I use a 1 spot 9 volt. They seem to be consistently good.
oneeyedog
You should get better result with a regulated PS, or regulate it using a 7812 - I got an image on my gallery and also was posted a couple of pages ago. It should help you to get rid of the hiss!!!
Kain
Glad you made it! Pics, please!!!
antiuser
grab the first scrap piece of vero and throw it togheter using my BULLETPROOF layout!!| :icon_lol:
Sorry if this was covered elsewhere in the thread, but is there a verified layout for a Subcaster? Vero, perf, or otherwise?
thanks renegadrian, I'll give it a try first chance I get .... where is your gallery????
john
Well yes, I did build the Valve earlier, and did build peppershredder with two 12AU7, but his Triple valvevaster made me really want it. So, I will go for it!
I thought on powering the pedal from 24VDC, so that I will regulate heater and LED voltage from 7812 and Anode voltage will go directly from the adaptor socket, but. Then It got me thinking, 7812 will not let 12V inputpower pass, it will lower it, so if I would like to power it from 12V adaptor then I am screwed and will have to remove 7812, but hey, that's why they invented switches.
At the moment I have some tubes in my storage, but I am afraid i dont have the right ones to make it sound good. So It will take some time to complete.
I have built several tube amps before and done some tube stuff, but I don't know everything about it, so I will stop by and maybe ask some questions.
One thing more, I have a Tube Driver somewhere. its not finished, because I didn't have the motivation to finish it. Has anybody done it? How would you compare it with this subject? I know its hybrid, but still.
I will go or at least try to build something out of these old Russian tubes:6N1P, 6N2P, 6N3P, 6N6P, 6N23P and so on. You could get them unused and really cheap. So that If anyone could get his hand on them, then you would know what to choose. But it will not happen in weeks, maybe after a month or so. Some research has to be done and there is not much time and finance to make it quickly.
So good luck to everyone!
One thing though. Could you all post the tubes you have used in this circuit and found it working and worth trying?
On more: if you look for oldschool rock sound, metal or something. Try Peppershredder from tubeTowns DIY section. This thing made me really enthusiastic about tubes. its not high-Gain or something, but its better than DS-1 and fun to build.
@ Served.....You could use a 24volt supply and a 7812. Run wires right from dc input to anodes ( to resistors at anodes). Run 7812 right from socket to heaters. Done. It works, you just end up having 3 24volt leads off the dc in as well as a 7812. I use 12au7 in all three spots on my latest triple tube build. I use a voltage multiplier I saw from Rick Holts Murder One design. Works quite well at 45volts. http://www.youtube.com/watch?v=YhyyYjY5CgA
Quote from: oneeyedog on September 09, 2010, 01:46:44 PM
thanks renegadrian, I'll give it a try first chance I get .... where is your gallery????
john
http://www.aronnelson.com/gallery/main.php/v/Renegadrian/
Hello, I am sorry if this has already been covered, and if it is common knowledge, but I am new at this stuff, and am very excited to build myself a valvecaster. I only have AC power converters, no AC to DC. Do I need to rectify the AC to DC to have this work, or will the normal step-down AC adapter work? Thank you.
Quote from: jcgss77 on September 13, 2010, 07:04:20 PM
Hello, I am sorry if this has already been covered, and if it is common knowledge, but I am new at this stuff, and am very excited to build myself a valvecaster. I only have AC power converters, no AC to DC. Do I need to rectify the AC to DC to have this work, or will the normal stepson AC adapter work? Thank you.
No. You cant use AC to make it work. Heaters can do their job with AC but no amplifycation is possible with AC.
But rectification is actually so easy to perform. It will acquire only like 6 additional parts, or less. Diodes(or diode-bridge - don't know how its in English), el.caps and that should do the trick. Of course if you want something more, filtering and regulation, then its a bit more complex, but not much. So give it a try and if its not enough, add what ever is necessary.
Egads, so much info in this thread!
So here is what I think I have figured out from all my reading and researching:
This is the simplest overdrive valve circuit and any mug should be able to build it,
The schematic on the first page works. Blowed if I can make head nor tail of it corellating with another thread that says the valve heaters are pins 4 & 5. I assume a 9V power input works by virtue of resistor(s) feeding the tube with 6.3V twice so it's getting 12.6V in total just like its name 12AU7, not sure on the maths to verify that, I just take these things on faith.
It's a little bit noisy but will run fine with a wall wart style unregulated 9V.
It's a little dark toned for some but all the vids I saw sounded cool to me.
I want one and that means I have to buy some components which I don't have. Nobody seems to sell a kitset for it. How come? Does Mr Matsuwotshisname retain rights to it that nobody is allowed to profit off it?
Going shopping online I am struck by so many different capacitors it makes my head spin. Can somebody please point me at the right ones? Ceramic, monolithic, metal film, polyester??? Nothing as low as 9V so I guess a 50V works ok??? I think I've got the value scales figured out.
Pots I have found locally online don't specify if they are linear B or logarithmic A. Gee, you'd think I actually knew what I was talking about. I guess you learn a lot in a day when you have to.
I'm in New Zealand. We have a "Dick Smith" in town, a lot like radioshack, prolly copied from RS actually. Anyway, I should be able to get correct pots, resistors and capacitors off the shelf if I ask their guy the right questions? Any tips?
use a regulated dc power supply. I use a 1 spot 9 volt. You can run 9 volts to pin 5 and ground pin 4. Works great. 100k a pots and 50 k b pot are the right ones I believe. %0 volt caps are fine. I use poly or whatever is available and they all seem to work. Antique electronics was selling a kit that I believe is this pedal. You can build your own for about a quarter of the price. There are only 4 caps and 4 resistors 3 pots a tube a socket a dc jack and a box. An extra cap and 7812 on the dc jack make it quieter. Renegadrian has the cool vero layouts that are tried and true. Schematic on first page works as well. Welcome!
Thanks. Is that a typo, %0 V caps??
I tested my power supply with mulitimeter and it's putting out 9.2V with no load, rated at 1000mA so I could prolly run three off it, but it doesn't say anything about being regulated as such.
Valves are very pricey in New Zealand but I see some bargains on ebay so might have to go there. They all claim to be tested NOS but who really knows? I haven't found anyone selling the tubes and the sockets together yet. Stuff paying two lots of shipping.
I tracked down Renegadrian's layout and it appears same as the front page one but done on that stripped board stuff, might have to get some of that too, looks real handy to solder onto. Is that the vero or is that the drawing program name?? I'll find out shortly!
IT WORKS!!!!!!!!!!!! :icon_mrgreen: not that I ever doubted the advice, I got the 7812 and cap today and.. no noise. thank you kindly for the advice. I have it built in a cardboard box!!! but now that it works i will get a proper enclosure, and post pics when I'm done. thanks again
:icon_wink:
cheers
john
Thank you for the direct replies. ;D
Just to ask-is it really a good idea to run the whole 9v to the filaments? Don't they want 6.3v with 300mA, or 12.6 v with 150mA? I thought I had read earlier in this thread that going more than 10% over or under was bad?
Sorry about the typo.....50 volt caps should be fine.yes the striped stuff is vero board on renegadrians layout. 9 volts on the heaters seems to be ok as well. I have been running them on 9 for a long time and they are still working great! Antique Electronic Supply sells tubes and sockets I believe. Small Bear Electronics is a great source as well. 16 bucks for a tube and 2.20 for a socket. They have all the caps enclosure etc. A good one spot shopping place to be sure. I recomend using 100 volt caps on these as once you build it you may want to start running on higher voltage.....it gets kind of addicting imho...good luck and hope this helps.
Quote from: jcgss77 on September 14, 2010, 04:49:37 PM
Just to ask-is it really a good idea to run the whole 9v to the filaments? Don't they want 6.3v with 300mA, or 12.6 v with 150mA? I thought I had read earlier in this thread that going more than 10% over or under was bad?
I read that too and it confuses me no end trying to figure it out off the schematic. I'm not even sure I got the good oil on which pin is which in the valve so it ended there for me.
wot I learned at highschool:
If you put resistances in series then then the voltage each part consumes in turn is in proportion to the resistances.
Power is voltage drop x current
So I can see how applying 6.3 volts to two heaters seperately is the same power consumption as 12.6 volts to them both if they were in series with each other. I just don't see how the wiring is doing that.
All the yap about shouldn't it be 12V is just guys who know even less than me messing with it, finding it makes more noise without going bang and then going "rarara it does need 12V", when they are now overpowering theirs if they kept the same circuit. Good luck to their valve if I'm reading it all right.
aarg, after more reading it looks like the pins 4 and 5 are indeed the heaters but they are connected together in series (via a disused pin 9) straight off the 9v to ground. So it looks like the heaters indeed being run at somewhat less than ideal power input after all! Any fool can see that! Apologies.
I have a multi voltage adaptor that does 12V so I guess that's a better bet. If I do that do I need to change anything else?
Is it possible to parallel the heaters off pin9 , ground 4 and 5 and get clever with that voltage regulating filter scheme to drop 9V down to 6V regulated. Anyone done it that way?
Well they will heat up, but I remember somewhere, that they don't actually like lower voltages. They last less or something like this.
Quote from: served on September 15, 2010, 11:34:35 AM
Well they will heat up, but I remember somewhere, that they don't actually like lower voltages. They last less or something like this.
This concerns me, although nobody complains that their valve craps out prematurely on the 9V.
Can anyone confirm my very limited understanding of the circuit please? The way I read it the tube heaters are in series and they are parallel with the rest of the circuit off the power supply, meaning thay get the full supply voltage whatever that is, 9V being the original standard, 4.5V per heater plate.
My cunning plan, ( ref BlackAdder, Baldrick ) is to throw the 9v into a voltage dividing scheme for the heater side, onto pin 9 @ 6.3V and ground the pins 4 and 5. That could be a very bad idea if I misunderstand the nature of pin 9. Still need to get a grip on voltage division. I guess I need to know the internal resistance of the heaters when they are up to temp. Do I infer that off the power consumption? Sheesh, 5 days ago a valve was a thing that glows inside an amp and makes lots of noise.
Anyways, valves have been evilbayed, enough for another project or three if they are all good. I got a 4 pack of "tested" NOS Sylvania Baldwin organ 12AU7 for 16 buckeroo + a Raytheon just because the seller had it cheap and it didn't cost any more to ship.
EDIT, just looking up specsheet on 12AU7, they say one is good for a 5w, presumably clean, power amp. Mamamia, Valvecaster on 'roids. Doesn't tell me what the heater resistance is but it sure looks like pin9 is common to both plates.
RE EDIT Ok, 300mA at 6.3V makes for 6.3/0.3 = 21 0hm from the parallel pair of heaters. 9v @.3 amp needs 30 ohm so I need to put a 9 ohm resistor soaker into the heater circuit to deliver 6.3V. Did I get that right?
btw The power supply has a doofer in the line about an inch long and thick as a finger. I'm guessing that's there to regulate and/or stop hum?
and by and by polishing off more of this monster thread.
Zambo, you RAWK. I'm a bassist but I love rock guitar and run a jam session at a bar. I'm building this thing for the guest artists to rock out with. I think your "triple rectifier" version will be next once I get my building chops.
@ Lowend. Thanks! I wouldnt worry to much about the heater voltage thing. Cathode stripping is what occurs if you run to low of a voltage and no one has reported a problem with it since I started reading the post. I have run quite a few versions of these for about a year now with no tube replacement and I gig with mine 4 to 6 times a month. 12.6 volts to pin 5 and pin 4 to ground is good. I rum 9 to pin 5 and 4 to ground. Havent tried using pin 9 yet. I think you put 6.3 volts to pin 4 and pin 5 and run 9 to ground? I think....but in not positive. I just do it the other way and never worry about it. Baldwin organ tubes work really well by the way. I use those all the time. The old organ speakers are awsome if you can find them too. I got some jensen 8 inch speaks from my tube guy. He said they are from an old balwin organ? Anyway, I love them. Good luck and rock on!
Thanks for the help. The vid where you were running a higher voltage one into a wee fender blues junior was tres cool. I've got a wee solid state combo that we mic up. It's got a very nice rich clean so hoping my valvecaster does something similar. With the same valve as yours that's a good start.
I think I have confirmed my own maths for the drop resistor in the heater by comparing it with the answer someone else got to 18V. Still not sure how to wire it though. Does it matter which is neg and pos on the heater? My guess is it shouldn't.
I think it does matter....let me see what i can find... here we go http://tdsl.duncanamps.com/show.php?des=12AU7 this place rules for tube info. Looks like 4 and 5 are hot and 9 is ground for both. Duncan amp pages has been a life saver for me. Read tubes for dummies on the home page of this sight as well. Awsome info and very helpfull.
This one I presume http://www.diystompboxes.com/pedals/tubedummy.html (http://www.diystompboxes.com/pedals/tubedummy.html) ta.
Thinking about it some more, it can't matter as in one scheme 4 is hot and the other it's the ground, quid pro quo it doesn't matter. Cool. Maybe I'll get to build a real amp one day.
I had another look at my wall wart and it's obviously not using a typical lump of coils transformer because it weighs hardly anything. I figure it must be some fancy electronic deal, regulated and filtered so I'm probably good without the mystery capacitor off the side. But for the extra 20c it would be good to throw one onto my order if someone can help out.
Well there is a problem with impulse adaptors. Their output is not flat enough. There are only very few models that suit for the purpose. But if you try it and it will pass, you are the lucky one.
As for the pins. Then there is no difference between the pins. Heater acts like a lightbulb. It has only repressive effect (like a resistor). No matter which way the current flows.
If using AC for heaters then there is no different also, but you could avoid some disturbance if you try to change the wires.
Google isn't picking up "impulse adaptor" so I'm stuck on that. It's similar to this one but 1A: http://www.sparkfun.com/commerce/product_info.php?products_id=298 (http://www.sparkfun.com/commerce/product_info.php?products_id=298)
The phrase might be wrong, I am not sure, its not my native language.
EDIT: The correct phrase is "switching battery eliminator" I think.
I have tried sever of thouse, they were cheap for me and I had resources to try a lot of different models, but no luck for me.
Oscope showed impulses for most of them. So I was suggested to stay to transformer based adaptors.
Its very offtopic, but I hope you don't mind.
Mind? Not at all. I must have missed the part where it said you can't run a valvecaster on a switching supply. Did yours have the cylinder doofer wired into the lead like mine? I wonder if that is there to clean up the power.
EDIT, reading around the "1spot" seems popular and it's a switching supply so I'm thinking this is a case of ymmv.
Well actually in my experience, I have not tried it with valvecaster, you can be the first one, it doesn't work in audio circuits.
I have tried to smooth it up and filter it and so on, but without any success. Have tried various pedals, amps, op-amps and so on. But hey! Try it out, there is nothing to loose only to gain some knowledge!
Just for knowledge purposes, if you power the heaters to pin 4 or 5, it doesn't matter. If you ground pin 9, it will only power the heater that has the power connected, then complete the circuit to ground, leaving the other heater unpowered.
I am pretty sure that I read somewhere on this thread that someone uses laptop psu's, and I am pretty sure that most, if not all, are switching. So I would believe that if you have good filtering and/or regulation, it should be ok.
Quote from: zambo on September 14, 2010, 11:37:20 AM
use a regulated dc power supply. I use a 1 spot 9 volt. You can run 9 volts to pin 5 and ground pin 4. Works great.
not the first to use a "1 spot", maybe the first to use 6.3V
parallel but I really doubt it.
Quote from: zambo on September 14, 2010, 11:37:20 AMAn extra cap and 7812 on the dc jack make it quieter. Renegadrian has the cool vero layouts that are tried and true...
Just wondering if you think it necessary for the extra bits? I'll have to revisit that 7812, I thought it needed extra volts to power it.
Yep, needs extra volts. I'm gonna assume my switching 9V power supply is already regulatated and go with a simple capacitor filter to take out any hiss it may or may not make. I know it's simple because I can't find an explanation for one in a good half hour of searching :icon_confused:
I found a bunch of threads that got no further than some resident posting the link to the Rolls Royce DIY powersupply of bliss, not gonna happen. I have read in passing about using a cap and a resistor, or just a cap but I'm short of specifics. Somebody please help so I can order the sucker with the rest and know where to put it.
My 9v is going to 4 and 5 and I'll ground 9 with a resistor as I posted earlier for 6.3 V parallel heater operation (patent applied)
Just put Electrolyte cap there. - to minus and + to plus and that's the deal. (if this was what you were asking)
Thanks for that, I did some more digging and have ended up plunking for a 220 and a 470uF to try out in the absence of anything more specific.
Quote from: lowend on September 15, 2010, 12:17:41 PM
My cunning plan,
RE EDIT Ok, 300mA at 6.3V makes for 6.3/0.3 = 21 0hm from the parallel pair of heaters. 9v @.3 amp needs 30 ohm so I need to put a 9 ohm resistor soaker into the heater circuit to deliver 6.3V. Did I get that right?
btw The power supply has a doofer in the line about an inch long and thick as a finger. I'm guessing that's there to regulate and/or stop hum?
I have struck a hitch in my cunning plan so it makes me wonder if i got the maths right.
putting .3A thru 9 ohm at 2.7V makes I^2*R = .09x2.7 = 0.243W which is right on the 1/4W limit of the resistors commonly sold. Seems a bit underengineered! All good?
Anyone know much about those inline doofers? The exact same style of doofer on a similar supply here at Godlyke http://www.godlyke.com/power-all-digital-power-supplies (http://www.godlyke.com/power-all-digital-power-supplies) (mine's not Godlyke)
Ok. I have spent the last 2-3 hours combing through this thread and I still cannot find any layout/wiring info for a 12AX7 tube! All of the posts I read allude to 12AU7 and 12AT7. Even some soviet tubes but NO 12AX7s!
Can someone point me in the right direction? Did I miss some info in this thread about using the AXs?
Quote from: Govmnt_Lacky on September 19, 2010, 07:23:41 PM
Ok. I have spent the last 2-3 hours combing through this thread and I still cannot find any layout/wiring info for a 12AX7 tube! All of the posts I read allude to 12AU7 and 12AT7. Even some soviet tubes but NO 12AX7s!
Can someone point me in the right direction? Did I miss some info in this thread about using the AXs?
All the 12a?7 tubes have the same pinout.
Quote from: R.G. on September 19, 2010, 07:30:16 PM
All the 12a?7 tubes have the same pinout.
I agree however, they do not all have the same gain value nor do they all work well from 9V. I do remember reading about that in this thread.
What I did not see was any solution to the higher voltage requirement or a solution for the proper usage of the increased gain.
Basically, I am throwing this out there to see if this has been discussed already or whether it needs further exploration.
Ideas??
What has been stated about the 12ax7 is that it doesn't sound good in this low-voltage circuit. There are better designs out there for those. This circuit is intended for a boost and light overdrive, which is what you get. Actually, I am very pleased and surprised with the distortion you get from a 12at7, which I use. Throw it on your breadboard and see. If you need more gain, do a 2 tube version.
Quote from: Govmnt_Lacky on September 19, 2010, 07:37:23 PM
I agree however, they do not all have the same gain value nor do they all work well from 9V. I do remember reading about that in this thread.
What I did not see was any solution to the higher voltage requirement or a solution for the proper usage of the increased gain.
Sorry. I misunderstood your question from the "wiring and layout" thing.
12AU7: amplification factor 20
12AT7: amplification factor 60
12AV7: amplification factor 41
12AY7: amplification factor 40
12AX7: amplification factor 100
12AZ7: amplification factor 60
There are also many other tubes which have the "9A" dual triode pinout.
All of these were designed for running with 100V upwards on the plates. They can all be run at lower voltages, but the consensus I've heard is that there is a starved or grainy quality to the sound from doing that.
There exist (or existed) tubes designed to run from significantly lower voltages, usually for portable or car radios.
QuoteBasically, I am throwing this out there to see if this has been discussed already or whether it needs further exploration.
It's been discussed a lot, although I don't think much of that discussion was here.
The bottom line is that to get a lot of gain with a tube you can actually buy replacements for, you're kinda stuck with the 12A?7. They can work at voltages in the 30-50V range, but there is a characteristic sound to that which some people like and some people don't.
Quote from: lowend on September 19, 2010, 01:12:45 PM
Thanks for that, I did some more digging and have ended up plunking for a 220 and a 470uF to try out in the absence of anything more specific.
Quote from: lowend on September 15, 2010, 12:17:41 PM
My cunning plan,
RE EDIT Ok, 300mA at 6.3V makes for 6.3/0.3 = 21 0hm from the parallel pair of heaters. 9v @.3 amp needs 30 ohm so I need to put a 9 ohm resistor soaker into the heater circuit to deliver 6.3V. Did I get that right?
btw The power supply has a doofer in the line about an inch long and thick as a finger. I'm guessing that's there to regulate and/or stop hum?
I have struck a hitch in my cunning plan so it makes me wonder if i got the maths right.
putting .3A thru 9 ohm at 2.7V makes I^2*R = .09x2.7 = 0.243W which is right on the 1/4W limit of the resistors commonly sold. Seems a bit underengineered! All good?
Anyone know much about those inline doofers? The exact same style of doofer on a similar supply here at Godlyke http://www.godlyke.com/power-all-digital-power-supplies (http://www.godlyke.com/power-all-digital-power-supplies) (mine's not Godlyke)
I'm surprised nobody spotted my mistake, perhaps they were distracted. I was bored at work and rehashed it and got a fright. Good thing I have yet to order the bits.
power= I^2 * R = 0.3A * 0.3A * 9ohm = 0.81W far too much for a single 1/4W resistor methinks. Being that they don't stock any gruntier ones I guess I'm stuck with 4 of them paralleled on the vero.
What's the current limit on vero at 9V anyway?
Put some solder on the lines and you will be fine!
I have one questin. How much voltage this kind of schematic will hold?
Can I just put 200V on anode without changing anything (except caps)?
Almost forgot about this thread. I never finished the twincaster and when I came back there's allready a tri-caster :D
So naturally I want to build that now. Here's the casing, it's mahogany with the metal part made out of an old propane tank warning sign. The Shell - logo
is still on the inside of the case. Kinda quick and dirty, looks like something out of an old sci-fi movie. Think I'll just shine some and start building the thing ;)
(http://i115.photobucket.com/albums/n302/Rg505bk/P9200177.jpg)
(http://i115.photobucket.com/albums/n302/Rg505bk/P9200179.jpg)
Quote from: Govmnt_Lacky on September 19, 2010, 07:23:41 PM
Ok. I have spent the last 2-3 hours combing through this thread and I still cannot find any layout/wiring info for a 12AX7 tube!
Can someone point me in the right direction? Did I miss some info in this thread about using the AXs?
To use a 12AX7 the pin out is the same, but you will want to move R1 and R4 (the grid leaks). Instead of connecting them to ground, connect them directly to the 9V supply.
(You may also want to experiment with connecting just one of them to 9V, the other to ground as normal).
I can say now that you can use
Russian tubes
6H1П-l(12AU7 and 6H2П(12AX7)
They work just fine.
6H2П gain factor is 100
6H1П gain factor is 35
But! Be Aware! 6N2P heater votalge is 6.3V, its filaments are connected paralel, so you cant just replace 12AX7 with this one.
Hi, 1st post. I've read this thread back and forward and I've decided to build a Twinvalvecaster first and a Trivalvecaster second. Next weak I'll buy the tubes, I have all other stuff. I'm pretty sure that I'll have many doubts in the process but I'm confident in this forum. First doubt :P I have an old PS Input: 120V AC 60Hz 15W Output: 9V DC 1Amp Well, at least that's what it says, but it throws me an output from 13.27 volts to 13.31 volts. Do you think I can use it to feed my valvcaster? If not, I'm really decided to build my own PS too.
Wish me luck. :icon_wink:
"Those who fear darkness have never seen what light can do."
9 volt 1 amp dc should work if its filtered well. Dual casters are cool. Tricasters are sweet too. Good luck! If you read this forum all the way through you know all there is to know about these things!
Quote from: kaalaraab on September 27, 2010, 01:18:25 AM
Output: 9V DC 1Amp Well, at least that's what it says, but it throws me an output from 13.27 volts to 13.31 volts.
Hi.
The reading you get is not the real output, it is Electromotive force. You will need to use somekind of load to measure how many voltage it gives. For example, build the pedal and power it from this adaptor and then measure the voltages. Your adaptor will give 9V if the flowing current is 1A. If its less than 1A then the voltage is higher. If its higher than 1A, then the voltage is lower than 9V.
There are some IC controlled adaptors also. Their output is regulated to only give the voltage that is written on the package.
Just for information.
Good luck!
Hi!
Did anyone try higher voltages than 18 V DC? Of course not for the heating, just for the rest...
Does it makes sense? How does it sound?
I dont like so much, that the sound is a bit "muffy". Would it get better with 18 V? So far, I am running with 12.
Regards
Dongle
Hi Dongle, I have one running at 63 volts and it sounds great. One of the characteristics of starved plate designs like this is an abundance of bass and treble with a huge cut to the mids. So if you wanted to counteract that you could always use a smaller input cap like a .002 or .003uf for caps 1 and 2. I have used .001 as well. I put them on a dpdt toggle so i have a fat and skinny switch....otherwise...yes raising voltage gives more mids and "balls" . I have a 3caster ( I call all mine Voltron ) running on 45 volts as well. I love it. You have to tame the highs between stages. I throw a .0005uf from anode to ground on all the stages. remeber to use caps and resistors rated for new voltage requirements! Hope that helps. Oh yeah...above 30 or 40 volts doesnt seem to make a huge difference in sound. I am starting to run them at 150 and 200 volts so I will post results when I get some done. :icon_smile:
Thanks for that detailed answer! My english is notgood, so I have to ask again, although you wrote it:
What does it mean "above 30 or 40 V doesnt seem to make a huge different in sound"? Does it mean it is the same if I use 30 or 90 V? Would I hear something if I go fom 12 to 18 V, or should I try to make the big jump to 40?
The problem is; I cannot find DC power supplies with hogher voltages than 24 - and these are seldom as well! Could I use one of the ICL7660 to double the voltage? But they only work with AC and are not so powerful I guess...
Could you post your powersupply and Valvecaster-schematic? That would be great!!
For the resistors and caps: I just have to raise the power the resistor can consume, right? The values stay the same, right?
He ment that 30V and 40V sounds the same. If you go 90V then it will make a difference.
If you cant find DC adaptors, then use AC and rectify it with diodebridge (4 diodes and a cap)
Resistors may stay same, caps have voltage limitation.
Thanks!
So I really want to try it with higher voltage...
Of course the heating remains at 12 V.
But how much power should my supply have for 30 / 60 / 90 Volts? If I understand it correctly, not very much... but I am not sure about this... Can someone tell me, the mA or Watt - number?
CU
Dongle
Quote from: Dongle on October 01, 2010, 04:41:23 AM
But how much power should my supply have for 30 / 60 / 90 Volts? If I understand it correctly, not very much... but I am not sure about this...
Most of the current is for the 12V 150mA heater. You only need a few extra milliamps for the anodes / LED. 200mA would be more than enough.
Hey guys, Sorry for my absence, I have been working hard on a new project......more on that later! I use a voltage multiplier that i found on the Murder One thread by Frequency Central. It works quite well and the schematic is on there. I am using the ic from small bear that is marked lt1054cp . Like this alot and it has enough juice to run the 3 tubes anodes easily. I dont have a schematic for the Voltron pedal ( triplecaster ) but its pretty easy. Chain three valvecasters in series and change all the input caps ( cap 1and 2 ) to .002uf. thats a good start. At higher voltages i have found that putting a .0005uf (500pf) from anode to ground stops some of the oscilations. I am not an experienced preamp designer so do this at your own risk. for real! If merlinb or anyone else wants to offer advice...take it. They are smart.PM me if you need to get ahold of me faster as this sight only notifies me of private messages. Good luck! G
Thanks!
I will try higher voltages, as soon as I manage to implement them ;)
I am looking forward to it - and hope for a better sound...
Cheers!
Here's my layout that I made when I built my triplecaster: http://jrmcgrath.com/images/triple%20valvecaster.jpg (http://jrmcgrath.com/images/triple%20valvecaster.jpg).
It's not the most "proper" of layouts, but it worked. =] I think I have the resistor on the master bypass LED on the wrong lead though.
So many pages on this topic I don't know if this has been covered sorry if it has. IS there a way to convert this to a clean boost I've been experementing a little but cant get it right. Thanks for the help
I hear if you change the plate resistors too a lessor value it makes it cleaner. Change r2 to a 100k and see if that helps you.
thanks is there a way to get rid of the gain knob i could replace with 50 k resistor but wouldn't that just keep the distortion in?
no it sets the "bias" so that the tube would run cooler. Straight to ground is max distortion. I would go about 25k if I went that route.you probably want some gain. Actualy the option of the knob is nice I think.
yah ill probably keep it in but I'm looking for a clean boost to run into a solid state frontman and to boost my strat into some distortion pedals. sorry one more question if i raise the 1uf cap will that raise the volume also sorry I'm slowly figuring all this out and thanks for the help.
no apologies needed man, we are all friends and everyone here is really helpful to everyone else from what i can tell.Raising the 1uf cap wont change the volume as far as I know. I believe it blocks the dc from leaving the pedal while allowing all the guitar ac frequencies to pass. Raising the plate voltage dramaticly increases volume. Are you running nine or twelve volts? If you are rtunning either one and want more volume, take a lead from the dc input to run the heaters only. Take another lead from the dc in and run it into a voltage multiplier and run that on your plates. 18 or 24 volts will give you ample volume and you will here an improvement in the mid frequencies as voltage goes up. Voltage multiplier I use is on the Murder one thread started by frequency central on this forum. Its cheap and works well.
yah i've been trying to run at 12volts but haven't had any luck I think i need new 12 volt wall wart any idea of the MA it should run at ?
with no voltage multiplier i have run one on a 200 ma. I think its a cheap dan electro one. What is the prob with the one you have? Noisey or motorboating stuff?
just plugged it in and theres just a high pitch squeal have a 12 volt dc
what schematic did you use and what tube are you using?
The matsumi valvecaster with 12au7 its the one from the start of this thread.
got any boss 9 volt tip neg adaptors around?
Nope but ill get one thanks again
Sorry - done...
Quote from: Dongle on October 18, 2010, 11:08:53 AM
Hi guys!
Why is C3 an electrolytic cap? Can you also use ceramics or films for this?
Thanks!
Dongle
C3 is electrolytic because 1uF caps most often come in that sort of package. But you could use any 1uF cap you have. Actually doesn't even need to be 1uF, you could try all kinds of values in there to get different sounds. I'd say anything 0.001uF to 10uF.
Thanks! I just found that out... Thats why I changed the post. Sorry, that I did not manage before I posted...
Best regards!
This is a great project, i just finished this and worked on the second try ( switched two wires which turned it into a radio when i touched ground ???).
It is my first project and i'm very happy with it.
The sound still is a bit grainy for my taste. I run it on 12V with a National 12au7a German made tube. The only mod i did was to put a 22nF cap on c1 to make it humbucker "friendly" and used a dptd footswitch for true by-pass.
Are there any other builders who use this little monster on humbuckers?
yep! tons of us! Glad you had success on your first build! Congratulations :)
Finally I exchanged C1 and 2 with 3nF - now I also like the sound! Not so undefined bass anymore...
But still I will try to raise the voltage... Just orderd two LR8s.. I am going to try implementing a potentiometer to control anode voltage on the fly. So I can easily hear, if it makes a different or not.
I will see...
Hi
I'm trying to put a little valvecaster together, but to no avail. I'm getting really weird voltages and I can't seem to figure it out. Maybe some one could point me in the right direction. Here are my voltages @12.6v:
pin 1: .5v
pin 2: 12.6v
pin 3: 6.5v
pin 4: 12.6v
pin 5: 0
pin 6: 1v
pin 7: 12.6v
pin 8: 12.6v
It seems like my power is coming in through the ground, but I can't seem to figure out why. Am I correct in my assessment? Any suggestions?
Thanks!
OK. I realized that I was measuring my voltages backwards - whoops!
The 12au7 lights up, but I get nada. No sound, just hiss. Here's my updated pin voltages:
pin 1: 2.8v
pin 2: 0v
pin 3: .8v
pin 4: .8v
pin 5: 12.6v
pin 6: 6.5v
pin 7: .2v
pin 8: .8v
pin 9: 7.6v
Help!
Here's mine from a working unit with gain at maximum. Yours are not that far off the mark. Cheack all connection, resistor values and off board wiring (!). As yours are close to good I'd suspect the off board wiring.
Pin 1: 3.02v
Pin 2: -0.518v
Pin 3: 0.00v
Pin 4: 0.00v
Pin 5: 11.97v
Pin 6: 8.21v
Pin 7: -1.285v
Pin 8: 0.00v
Pin 9: 5.91v
Quote from: Freekmagnet on October 25, 2010, 12:45:26 AM
OK. I realized that I was measuring my voltages backwards - whoops!
The 12au7 lights up, but I get nada. No sound, just hiss. Here's my updated pin voltages:
pin 1: 2.8v
pin 2: 0v
pin 3: .8v
pin 4: .8v
pin 5: 12.6v
pin 6: 6.5v
pin 7: .2v
pin 8: .8v
pin 9: 7.6v
Help!
If the polarity of your wallwart is backwards the heaters will still light up, but you will get no amplification, fyi. Not the likeliest problem, but something to check none the less.
Quote from: MikeH on October 25, 2010, 11:03:37 AM
Quote from: Freekmagnet on October 25, 2010, 12:45:26 AM
OK. I realized that I was measuring my voltages backwards - whoops!
The 12au7 lights up, but I get nada. No sound, just hiss. Here's my updated pin voltages:
pin 1: 2.8v
pin 2: 0v
pin 3: .8v
pin 4: .8v
pin 5: 12.6v
pin 6: 6.5v
pin 7: .2v
pin 8: .8v
pin 9: 7.6v
Help!
If the polarity of your wallwart is backwards the heaters will still light up, but you will get no amplification, fyi. Not the likeliest problem, but something to check none the less.
Thanks. I tried flipping the power input leads, but still no go. I tested the polarity of the power and it seems to be correct. I have another wall wart, but that one doesn't seem to be any different. I built a little voltage regulator, so I might try putting a pair of 9 volt batteries together and see what happens.
Tried different tubes yet? I don't think you should be getting any voltage on pin 4. I have built lots of these and they usually fire right up. What do you have it built on? Post some detailed pictures and let us have look. I have also wired it up with using either pin 4 or 5 being the hot and it works both ways. Check the tube and be sure it is good.
Chris
Unfortunately, I don't have any other tubes laying around. I live out in the middle of nowhere, so I'd have to order any extras. The tube is a new EHX 12au7.
I can post some photos. Here's a link to the layout I used for the rectifier:
http://www.tube-town.net/diy/lov/lov03-bananabooster-eng.html
Just ignore the top layout. I made my own on perf based on the schem posted on Beavis Audio. Here's my layout and photos. I omitted C1 deliberately - I play bass. Maybe that's why it doesn't work! Anyway, excuse the mess - I'm in trouble shooting mode.
Thanks.
(http://jeremykirsch.com/images/valvecaster_layout.png)
(http://jeremykirsch.com/images/2328_0010.jpg)
(http://jeremykirsch.com/images/2329_0011.jpg)
(http://jeremykirsch.com/images/2330_0012.jpg)
(http://jeremykirsch.com/images/2331_0013.jpg)
Hard to tell much from the pics. ??? If it was me I would take it apart and start over being very careful to check the layout. I can see you may have some issues with solder joints and trying to wire it all up with the socket pins gives lots of chance for error.
and put c1 back in. It stops the dc voltage from reaching your instrument. This happens more with low voltage tube projects for some reason. Scratchy volume pot is one of the symptoms of it.
Quote from: zambo on October 27, 2010, 02:15:45 AM
and put c1 back in. It stops the dc voltage from reaching your instrument. This happens more with low voltage tube projects for some reason. Scratchy volume pot is one of the symptoms of it.
I'll check it out for sure. Thanks for the suggestions. I guess I'm going to have to just pull all the wires out and do it again. :-\
I tried building one of these about a year ago and it sounded great with a battery but when I used a regulated power supply, it was just too noisy. Not sure if it was my soldering causing the noise or not. I was wondering if anyone had any thoughts on getting a pcb mounted socket and putting it all together on a piece of perfboard instead of soldering multiple components into the same hole? I loved the sound I got with a battery but was discouraged when I couldn't track down the source of my buzz.
sounds like it was a bad power supply experience. I use a 1spot power supply with great results and no hum. dane elctro 200ma power supplys work as well. I think even boss supplys work but i dont use them so i dont know from personal experience. If you look back in this thread Renegadrian has posted a vero board layout several times and it seems to work quite well. I bet its on the schematics and layouts page to. A cap from positive to negative on the dc input and a 7812 from ratshack helps things out as well. Hope this helps and keep building!G
Quote from: zambo on October 29, 2010, 09:22:32 PM
sounds like it was a bad power supply experience. I use a 1spot power supply with great results and no hum. dane elctro 200ma power supplys work as well. I think even boss supplys work but i dont use them so i dont know from personal experience. If you look back in this thread Renegadrian has posted a vero board layout several times and it seems to work quite well. I bet its on the schematics and layouts page to. A cap from positive to negative on the dc input and a 7812 from ratshack helps things out as well. Hope this helps and keep building!G
Yeah, It's a 12v 1spot supply. It's more of a hiss than a buzz. I've tried a cap across the dc input and it reduces it some but it's still there. I'll have to try the 7812 as it sounds like an easier mod than I previously thought. Nice to know I can get it locally instead of ordering from yet another supplier (have to order the socket from a tube supplier)
I saw the vero board layout when I was rummaging through the forum. I forgot that was there! I have an extra piece of perfboard laying around so That's what I'll probably use this time around.
Hey guys, i was looking at the pics from Freekmagnat. Please correct me if i'm wrong.Isn't a Elco with 1000UF not a bit much? Doesn't it cut of the signal?
I am new at this stuff and just build one of these. It works ands sounds ok, just getting a little hiss.
Finally, it worked! It really boosts up with a lot of gain, but some issues, a was thinking to skip it and start with the no-tone version, but I'm here primarily to learn, so I'll try to fix them.
Issues:
- A pretty loud hum.
- The led doesn't light up.
- The sound is a little bassy.
- The sound is less overdrived than I wish,
- The tube lights up much more than expected, I'm afraid I have voltage issues.
(http://img263.imageshack.us/img263/183/blackvalveivalve.jpg) (http://img263.imageshack.us/i/blackvalveivalve.jpg/)
Ideas:
- For the hum, integrate the Renegadrian idea with the 7812 regulator, and check out the ground bus.
(http://img64.imageshack.us/img64/5908/blackvalveibus.jpg) (http://img64.imageshack.us/i/blackvalveibus.jpg/)
-For led, just check out the wiring and the led itself.
- For the basst sound, change the capacitors value, I know That the no-tone version deals with this problem, but I want to make this version sound good.
- For the overdrive, I'll will experiment with other tubes: 12au7 and 12at7 of several brands. I'm using a new EH 12au7
- For the tube light, I'm going to post voltages, hopping somebody check them out, maybe the 7812 will fix it.
Thanks to you all, specially Rick and Renegadrian which contributions were must helpful to me.
(http://img575.imageshack.us/img575/4439/blackvalveiup.jpg) (http://img575.imageshack.us/i/blackvalveiup.jpg/)
(http://img826.imageshack.us/img826/676/blackvalveipres.jpg) (http://img826.imageshack.us/i/blackvalveipres.jpg/)
I've also buit the ValveCaster and experimented with it for a while but I'm stuck now... :icon_frown:
I didn't like the saturated gain it gave me so I changed R2 to 100K, lowered C1 to 22nF, added the SWTC2 tone control and stuck a Tillmann FET Preamp in front of it. Nice! But this could be better!
Yesterday, I made a voltage booster to get voltages up to 80 volts from my 12 volt input (Cioks Double Jack). This gave an enormous volume boost to the Chinese 12AU7 but also increased the dense, saturated gain it already had at 12v. I then tried a 12AX7: insane amount of volume and gain, up to a fat distorted fuzz. Not really what I was hoping for ;)
How do I decrease that saturated gain? Should I try to get a better 12AU7? Or maybe try a 12AT7?
Quote from: kaalaraab on November 03, 2010, 12:02:26 AM
- For the hum, integrate the Renegadrian idea with the 7812 regulator, and check out the ground bus.
It seems to help a lot, easy fix should be...
Quote
- For the bass sound, change the capacitors value, I know That the no-tone version deals with this problem, but I want to make this version sound good.
I myself find the Valvy a little on the bass side - tweak the input cap and it should be less bassy.
Quote
- For the overdrive, I'll will experiment with other tubes: 12au7 and 12at7 of several brands. I'm using a new EH 12au7
The first one I made has the same tube of yours, yes not a distortion for sure but a good overdrive.
Quote
- For the tube light, I'm going to post voltages, hopping somebody check them out, maybe the 7812 will fix it.
Simply check pins 4 and 5, they should read +-12V
Quote
Thanks to you all, specially Rick and Renegadrian which contributions were must helpful to me.
Glad if I can help you somehow!!!
@Harold: are you after a cleaner boost!? It shouldn't be that difficult to get with some fiddling I believe...
Quote from: Renegadrian on November 03, 2010, 12:28:38 PM
@Harold: are you after a cleaner boost!? It shouldn't be that difficult to get with some fiddling I believe...
I'm looking for a mild overdrive that's not overrsaturated and not overcompressed. I'd like to use it to push my old JCM800/JMP MV amps into high(er) gain terrritory for which I now use a Taiwanese black Ross Distortion (MXR Dist+ clone with Silicium diodes), but I'd like to explore the possibility of an all-tube signal clipping path. ;)
Current mods:
* Tillman Preamp to boost input signal and clarity
* C1: 22nF
* R2: 100k
*
EDIT: SWTC2 tone control
I'm going to breadboard the ValveCaster and fiddle with the caps and resistors some more. I already got the advice to lower C2 to 2-22nF and maybe add a cathode resistor(/pot) between pin 8 and ground to finetune the gain a bit more, next to lowering C1 to 1nF...
Quote from: Renegadrian on March 29, 2008, 08:43:02 AM
Quote from: tranceracer on March 29, 2008, 12:31:51 AM
Glad you got the problems resolved! :D
Did you place the 100uF across the +/- of the power leads?
put a 100uF cap across the DC jack (positive leg to positive rail, neg. leg to neg. rail), then, instead of connecting the positive rail directly to the circuit, connect it to the regulator's pin1, ground to pin2, and the circuit to pin3. Then screw it on the enclosure. It is a 7812.
The caps legs are soldered directly to the dc jack lugs...
Quick question, if I ground pin2, then screw it on the enclosure, due that the terminal 4 of 7812 is conected to pin 2, it wouldn't create a ground loop?
@ Harold..if you are after a cleaner boost the adition of a 1meg pot between stages is good. It creates a pre and post type circuite. So after c2 put a 1 meg pot. do away with r4 as the 1m pot is your reference to ground for pin 7 now. You should be able to limit the amount of signal going into stage 2 now. put another 50 k pot from pin 8 to ground just like the gain pot of pin 3. Assuming this is all on a bread board. Tweak to taste then start measuring things like the resistance of the gain pots. You can replace them with fixed resistors if desired. Let stand 5 minutes and serve warm with beer..Good luck, hope that helps. G
Done!! ;D I'm so happy that finally, after 3 months of trying with tree or four proyects, and a little painful curve or learning :P I manage to assamble one DIY, and not any DIY, this rocks. I'm still wating for some tubes to arrive for try them all, and tomorrow in the studio I'm going to try my valve with diferent amps, guitars and bass, and configurations with other pedals. I'll try to record samples for you all, Thanks for the help, this tread has been enlighting.
(http://img822.imageshack.us/img822/2007/03112010518.jpg) (http://img822.imageshack.us/i/03112010518.jpg/)
The led lit up when I realize my confusion, I was using a 470k res :-[ instead of a 4.7k, at the end, I'm using a 1k resistor.
I change the 47nF in cap for a 22nF, bassy sound fixed. :icon_wink:
(http://img838.imageshack.us/img838/7561/03112010511.jpg) (http://img838.imageshack.us/i/03112010511.jpg/)
This fixed the hum problem, well, here in Mexico City the electical current is very fluctating, but at least, my valvecaster doesn't make a hum any louder than my Cooltron Big Ben.
(http://img822.imageshack.us/img822/5934/03112010515g.jpg) (http://img822.imageshack.us/i/03112010515g.jpg/)
Here it is, my first son :icon_biggrin:
Thank you all, spetially Rick and Rnegadrian, and everybody working on this proyect.
Next: Twincaster!!
Quote from: frequencycentral on September 09, 2008, 03:42:56 PM
Here's mine, running at 12 volts:
Pin 1: 3.02v
Pin 2: -0.518v
Pin 3: 0.00v
Pin 4: 0.00v
Pin 5: 11.97v
Pin 6: 8.21v
Pin 7: -1.285v
Pin 8: 0.00v
Pin 9: 5.91v
These are my readings:
Pin 1: 3.21v
Pin 2: -0.35v
Pin 3: 0.00v
Pin 4: 0.00v
Pin 5: 12.05v
Pin 6: 1.84v ??
Pin 7: -0.08v ??
Pin 8: 0.00v
Pin 9: 5.95v
Is there a problem on pins 6 and 7, or those are normal readings?
seems like pin 6 should be getting more voltage than that. I know a lot of people have posted voltages throughout the forum thread. You might look back a few pages on here to find out. I dont have a digital voltage meter :icon_redface: so i cant measure to help you. Pin 6 seems low to me though.
Quote from: zambo on November 04, 2010, 01:43:46 AM
seems like pin 6 should be getting more voltage than that. I know a lot of people have posted voltages throughout the forum thread. You might look back a few pages on here to find out. I dont have a digital voltage meter :icon_redface: so i cant measure to help you. Pin 6 seems low to me though.
Yes, I think that too, what could be the problem? Could C3 or R3 (100k) being sucking the voltage?
Quote from: zambo on November 03, 2010, 04:25:02 PMAssuming this is all on a bread board.
...
Let stand 5 minutes and serve warm with beer..Good luck, hope that helps. G
Hi G,
I've just received a package containing all components to create another ValveCaster, this time on my breadboard. I got a lot of tips to unsaturate the valvecaster and I'm hoping I can try the first ones out this weekend...
This is the voltage booster I've used for feeding the plates:
(http://diy-layout.com/diyl/42/render) (http://diy-layout.com/42)
Quote from: zambo on November 04, 2010, 01:43:46 AM
seems like pin 6 should be getting more voltage than that. I know a lot of people have posted voltages throughout the forum thread. You might look back a few pages on here to find out. I don't have a digital voltage meter :icon_redface: so i cant measure to help you. Pin 6 seems low to me though.
OK, pin 6 still reads 2.00V. Here's where my theoretical knowledge is pretty lame. What happens if I change the value of R3 (100K)? Will that generate a problem with C3 or tone pot? And finally, do I need increase or decrease the value of R3 to give more voltage to pin 6?
before you do anything, I would do some research through this thread and see what the voltage measurements are supposed to be. I would bet you find them in the first 10 to 15 pages. It should work just the way the schematic is. Try work arounds after you figure out if there is or isnt a mistake would be my advice. I will skim through to see if i can find something in here. :icon_wink:
I found this from somewhere on here. Its a quote from Frequency Central. Hes really good at this so I think its from a pretty reliable source.
Here's voltages taken from my working Valvecaster, which I run at 12 volts:
Pin 1: 3.02v
Pin 2: -0.518v
Pin 3: 0.00v
Pin 4: 0.00v
Pin 5: 11.97v
Pin 6: 8.21v
Pin 7: -1.285v
Pin 8: 0.00v
Pin 9: 5.91v
Take measurements from yours with the tube in the socket, power engaged, and everything set to maximum and post them here. Also measure and post your power supply voltage.
[/quote]
Quote from: frequencycentral on June 05, 2008, 04:43:34 PM
Pin 1: 3.02v
Pin 2: -0.518v
Pin 3: 0.00v
Pin 4: 0.00v
Pin 5: 11.97v
Pin 6: 8.21v
Pin 7: -1.285v
Pin 8: 0.00v
Pin 9: 5.91v
DC power in is reading 11.99v.
Gain at maximum.
Edit: My gain pot is 100K not 50K.
OK, thanks, these are the right voltages. Pin 6 must be around 8V I made some test and with R3 at 22K pin 6 goes up to 6.2V, with all other pins going at right values, I only can think that there's the problem. I'm using Renegadrian's layout: http://www.aronnelson.com/gallery/main.php/v/Renegadrian/Valvecaster+v0_5.jpg.html
These are my readings with R3=100k
Pin 1: 3.21v
Pin 2: -0.35v
Pin 3: 0.00v
Pin 4: 0.00v
Pin 5: 12.05v
Pin 6: 2.21v
Pin 7: -0.08v
Pin 8: 0.00v
Pin 9: 5.95v
Pin 7 also looks suspicious to me.
These are my readings with R3=22k
Pin 1: 3.3v
Pin 2: -0.36v
Pin 3: 0.00v
Pin 4: 0.00v
Pin 5: 12.05v
Pin 6: 6.06v
Pin 7: -0.06v
Pin 8: 0.00v
Pin 9: 5.95v
What else I should test with multimeter to know if having R3 at 22k affects anything else?
EDIT: My power supply throws 22 volts, after the Renegadrians 7812 divice, I read 12.06V
EDIT 2:
With R3=10k my readings are these.
Pin 1: 3.26v
Pin 2: -0.35v
Pin 3: 0.00v
Pin 4: 0.00v
Pin 5: 12.05v
Pin 6: 8.3v
Pin 7: -0.05v
Pin 8: 0.00v
Pin 9: 5.95v
Well, R3=10k seems to fix the voltage on pin6 but, does it affects anything else?
pin 7 is a grid so it should have ac voltage while being played. pins 2 and 7 are basicly signal in for each triode. Pin 1 still looks low but im guessing. Whats going on with pin 9? I dont even use that one. I put 12 volts to pin 5 and ground pin 4 for the heaters. Besides those things you should be getting sound.
I just compared yours to freqcentral. You should be good now... :icon_redface:
Yes, thankyou very much, Greg. I put in the 10k resistor, and it sounds and sounds really good!! Now I'm having the overdrive I was, we all was, talking about! And now I'm ready to start with the Twincaster.
if you are looking for hi gain you might just go right to a three tube version..I have found I am happiest with that. I gig with it all the time in a hard rock band. Just a thought. Glad to hear you got it working right. This is one of my fav pedals ever. Simple but effective. Congrats!
Quote from: zambo on November 05, 2010, 08:17:53 PM
if you are looking for hi gain you might just go right to a three tube version..I have found I am happiest with that. I gig with it all the time in a hard rock band. Just a thought. Glad to hear you got it working right. This is one of my fav pedals ever. Simple but effective. Congrats!
I have seen your videos, and that's how I would like to sound (pedal sound and guitar playing :icon_biggrin: ) In special this one http://www.youtube.com/watch?v=qbDJYMAp6Mo&
I hope to achieve that sound from one stompbox one day, I tried the vibracaster and realized that I have so much to learn. So I decided to build them all: Twincaster, then triple valvecaster, then vibracaster.
Thanks for your help and your videos. I'll be around here for a while :icon_biggrin:
Well thanks! Glad you are like them and glad you are building! If you really like hi gain...I built this pedal using a valvecaster and I think aron nelsons smaxh drive. I think I went into the smash drive first then into the valvecaster but it was all in one box. It sounded really cool, then i used the parts to make something else. Run off groove has some real cool pedals to. Big daddy is a good hi gain that uses lm386 in it. Anyway, Thank you and welcome aboard etc.! :)
Just ordered some parts to try a second time at this on a piece of stripboard instead of putting everything on the socket. Also got some parts to build a Ruby. Hopefully I can make a halfway decent bass amp out of it! :icon_biggrin:
are you going to do a half watt bass amp? Awsome! Post sound clips or vids when done please!! If you look on the beavis audio sight he had a way to bridge 2 lm386 n4's for a one watt amp that is pretty cool. I did it once and it was pretty loud for fitting in an altoids can!
I've tried a lot of mods supplied in this topic, but I still don't really like the ValveCaster as a "real tube tubescreamer replacement" type of overdrive/booster so now I'm looking for alternatives and found a simplified 3-button Chandler(?) tube driver schematic:
(http://www.muzique.com/schem/tubedrvr.gif)
Has anyone tried to build it and compared it with the ValveCaster? Is this a nice pedal to build or should I go full monty with the 4-knob version with the bi-polar power supply?
Quote from: zambo on November 06, 2010, 08:07:14 PM
are you going to do a half watt bass amp? Awsome! Post sound clips or vids when done please!! If you look on the beavis audio sight he had a way to bridge 2 lm386 n4's for a one watt amp that is pretty cool. I did it once and it was pretty loud for fitting in an altoids can!
Yeah, I'm going to do the 1/2 watt version. I was planning on doing the ruby with the bassman mods and going from there. I'll probably build the 1 watt version with the same mods eventually. It's cheap enough to build that can try a few different versions! Might even try making one with a tube preamp section eventually.
Hi everyone,
i finished wiring everything, but i can't get it to work !
I followed the components scheme from the 1st page : http://www.beavisaudio.com/Projects/ValveCaster/MatsuminValveCasterWiring.gif
I have a more or less 16v dc power wallwart, which i regulate with a 7812 and 100uf cap, giving a stable 12v.
My voltages found on the tube are quite far from the ones that were posted previously of working valvecasters.
For example, for Pin 1 i have around 7v where other persons get around 3v.
I have my 12v coming well to the pin5, divided by two if i check with pin 9.
My first question is : are the potentiometers seen from the top or from the bottom ?
I wired those ones, thinking that they are seen from back. But now, as it doesn't work, i'm not sure anymore that it's the right way !
I will try to post tonight my voltages, and other questions, and perhaps some pictures of the wiring.
Thanks in advance.
Fabien.
Fabien, the pots are looke from the bottom. But I'm not really sure if there's a difference on that and I'm pretty sure that they don't affect the voltage on the tube's pins. In my first try with this project, I wired the pins counterwise, are you sure you're doing it wright?
Quote from: kaalaraab on November 08, 2010, 10:47:47 AM
Fabien, the pots are looke from the bottom. But I'm not really sure if there's a difference on that and I'm pretty sure that they don't affect the voltage on the tube's pins. In my first try with this project, I wired the pins counterwise, are you sure you're doing it wright?
I think so. Can you explain a little more ?
Seeing the tube from the bottom, the pins goes clockwise.
normally, it's right.
but i'll post some pics tonight, so that to get some help.
I'm quite sure i missed something, because it's quite an easy circuit ...
Fabien.
Here are my voltages :
Pin 1: 7.44v
Pin 2: -0.42v
Pin 3: 0.00v
Pin 4: 0.00v
Pin 5: 12.10v
Pin 6: 3.37v
Pin 7: -0.58v
Pin 8: 0.00v
Pin 9: 6.11v
and here is the link to some pictures of inside :
http://picasaweb.google.com/fabien.lahaulle/Valvecaster?authkey=Gv1sRgCJDXm8H27IeZNg&feat=directlink
as pin 9 is between pin 4 and 5, it usually reads half the voltage. It seems it's not a misoriented tube...
Quote from: fabienl on November 08, 2010, 02:53:08 PM
Here are my voltages :
Pin 1: 7.44v
Pin 2: -0.42v
Pin 3: 0.00v
Pin 4: 0.00v
Pin 5: 12.10v
Pin 6: 3.37v
Pin 7: -0.58v
Pin 8: 0.00v
Pin 9: 6.11v
and here is the link to some pictures of inside :
http://picasaweb.google.com/fabien.lahaulle/Valvecaster?authkey=Gv1sRgCJDXm8H27IeZNg&feat=directlink
--> i have added some pictures
I cann't see any error :icon_frown: Check for ground loops, and your 3pdt wireing, post a pictur of that. I don't think having 7v on the plate would be a problem.
Quote from: fabienl on November 08, 2010, 03:05:38 PM
Quote from: fabienl on November 08, 2010, 02:53:08 PM
Here are my voltages :
Pin 1: 7.44v
Pin 2: -0.42v
Pin 3: 0.00v
Pin 4: 0.00v
Pin 5: 12.10v
Pin 6: 3.37v
Pin 7: -0.58v
Pin 8: 0.00v
Pin 9: 6.11v
and here is the link to some pictures of inside :
http://picasaweb.google.com/fabien.lahaulle/Valvecaster?authkey=Gv1sRgCJDXm8H27IeZNg&feat=directlink
--> i have added some pictures
--> i've added some pictures of the 3pdt and around the 3pdt
This may sound dumb but did you ground everything together including the grounds from input to output jacks? I think thats a plastic box right? The circuite looks right but its hard to tell on the 3pdt switch. I dont wire them that way.
I wired 3pdt that way and it works. Just to be shure:
Lug 1 jumper to lug 2
Lug 2 jumper to lug 1
Lug 3 jumper to lug 8
Lug 4 ground
Lug 5 to input, in this case C1 I think
Lug 6 to output tip sleve
Lug 7 to led
Lug 8 to in tip sleve and jumper to lug 3
Lug 9 to volume lug 2
Hey so I'm new to the Forum, I found out about the whole Matsumin Valvecaster this whole forum was initially based off of, and I really want to try out building this thing with some mods. My idea coming into this is to build a high gain Tube distortion pedal. So I've skimmed the first 15 pages trying to find inspiration, and I'm just way too impatient to read through the entire thing, so I'm sorry in advance if what I'm thinking has already been covered!!!
So I was thinking of adding a (modified) SHO circuit before the initial Tube Boost stage, running it through a 12AT7 instead of a 12AU7, and having the whole thing run on 12v DC. If anyone can tell me what I should worry about trying to do all these mods, (re-biasing the tube, how and where I should wire the SHO, how the 12AT7 will respond as opposed to AU7, etc. etc. ) that'd be great. From what I can tell, it'd be awesome, but I'm a noob when it comes to Tubes and this is gonna my first Boost/Overdrive/Distortion pedal project (although I have made a couple pedals already so I'm not completely inexperienced)
anywho, anyone's feedback would be AWESOME! thanks
Quote from: Astronaurt on November 09, 2010, 04:41:11 AManywho, anyone's feedback would be AWESOME! thanks
If I may?
Breadboard it and experiment away! There are only a few components and each component change is reflected immediately. As long as you don't put more than 12v on the heaters, (almost) nothing can go wrong!
Astronaurt, welcome to the tube club!!!
Yeah someone has already experimented some of the things you say, personally I like a simple Tillman to push the Valvy, without trasforming it in a total different thing...just put it before the valvy input. An AT is a good choice, as other tubes too react well in this ckt. Basically you don't have to swap components if not to meet your needs/tastes, stock values work well wirth the above 2 modifications.
If you're after higher gain, check my tube star using the search button.
i am with harold on that thought. Try to build the valvecaster first then experiment with variouse boosts and distortions before and after. Hybrids can be cool. Arons Smash Drive is a cool distortion I have used with this to great effect. 12at7's are a little gritty at 12v, I have found three 12au7's in series to give pretty sweet distortion. Renegadrian has some really cool designs too! Tube Star i think is one that uses 2 12at7's. Good luck!
Just one AT at slightly higher voltage (+-50V) - it can also use an AU but there's less gain.
I'm new to the site, so Idk if I'm using the search function right! Could I get a link for the Tube Star? I'm not particularly interested in voltages above normal stomp box level, I'm building stuff so I can put on my Pedal Board and hook it up to my power brick mostly! I also just looked up the Tillman circuit cuz I hadn't heard of it before and it sounds like an idea worth checking out. If I want to adjust the gain on that though, I'm thinking I should sub a pot for either R3 or R4. Do I have the right idea there? I'm thinking off the schematic on this link:
http://www.till.com/articles/GuitarPreamp/
I think I'm going to go get components for the straight up Valvecaster this weekend after I finish my Wah Pedal I've been working on! Hopefully I can get it done soon! thanks for the input guys :) this thread is awesome as hell, I've learned SO MUCH STUFF!
Quote from: Astronaurt on November 10, 2010, 03:07:46 AM
I'm new to the site, so Idk if I'm using the search function right! Could I get a link for the Tube Star?
http://www.diystompboxes.com/smfforum/index.php?topic=74888.0
Quote from: Astronaurt on November 10, 2010, 03:07:46 AMI'm not particularly interested in voltages above normal stomp box level, I'm building stuff so I can put on my Pedal Board and hook it up to my power brick mostly!
You can use a voltage booster inside your pedal, like this one:
(http://diy-layout.com/diyl/42/render)
http://diy-layout.com/42
Quote from: Astronaurt on November 10, 2010, 03:07:46 AMI also just looked up the Tillman circuit cuz I hadn't heard of it before and it sounds like an idea worth checking out. If I want to adjust the gain on that though, I'm thinking I should sub a pot for either R3 or R4.
I've also put the Tillman preamp in front of my ValveCaster and like it al lot! I could not get the J201 to function correctly so I replaced it with an 2N5485.
(http://diy-layout.com/diyl/34/render)
http://diy-layout.com/34
Hey weird question but on my sockets I cant get a 5mm LED through the middle hole? Are the people doing this pulling the metal plug? Or maybe using a 3mm LED and if it's a 3mm what would the resistor be while running at 12volts? Thanks to everyone answering question on this thread great for all us Noob tubers (hehe good name for a band)
i think its a 3mm and I use a 4.7k resistor with my led's. I dont even know why actualy, I just always have....hmmm....never tried the light in middle of tube trick. Post pics when done if you would! Greg
theres pics on this thread around page 70 or so I think lol I'm gonna go a different way because I want the tube flat in the box so i can actually have it on my board without having to worry that much.
I used a 3mm led with a 1k resistor, 4.7k makes it less shinny. It fits well in the socket.
Am i the only one that cant see these DIY-layout pics? I'm probably doing something wrong but I'm interested in that voltage booster?
Quote from: clydeshere on November 11, 2010, 09:33:55 AM
Am i the only one that cant see these DIY-layout pics? I'm probably doing something wrong but I'm interested in that voltage booster?
Hmmm, that's weird. I never heard that before... Are they also invisable on the project's page? http://diy-layout.com/42
I cant even get that page to load for some reason?
Anyone know of a page on here that has a voltage booster 9 volt to 12 volt?
Quote from: clydeshere on November 11, 2010, 10:05:45 AM
Anyone know of a page on here that has a voltage booster 9 volt to 12 volt?
You could boost 9v to 18v and regulate it to 12v. But... It'll only handle 50-100mA so it won't be able to supply enough power to the heaters...
Quote from: clydeshere on November 11, 2010, 10:04:18 AM
I cant even get that page to load for some reason?
Even stranger! ???
Does anybody else have the same problem?
My browser loaded it just fine. I'm sure I lost the information somewhere, so, can any bady give here what kind of diodes, caps and IC are use on this voltage booster?
Quote from: kaalaraab on November 11, 2010, 12:12:22 PM
My browser loaded it just fine. I'm sure I lost the information somewhere, so, can any bady give here what kind of diodes, caps and IC are use on this voltage booster?
They are on the "Bill of materials" (BOM) tab on the project page?
Hi there,
Nooby here. I have a lot of digital gear and in contrast to that I have built some sweet valve amps. I want to build a dual Valvecaster to go in front of my valve amps to stay 100% analogue, but it appears the layout pictures for the dual valvecaster have vanished. I could design a dual based on the single, but I'm feeling a bit lazy and would like to just build the project without having to do any thinking. :icon_smile:
Could someone please post a layout diagram for a working dual Valvecaster?
Thanks,
Crusty
You can try must trusted Renegadrian's layout http://www.aronnelson.com/gallery/main.php/v/Renegadrian/Twincaster+rev+0_11.jpg
or point to point triplecaster layout by jrmcgrath13, just let out the third valvy.
Quote from: jrmcgrath13 on October 05, 2010, 12:18:20 AM
Here's my layout that I made when I built my triplecaster: http://jrmcgrath.com/images/triple%20valvecaster.jpg (http://jrmcgrath.com/images/triple%20valvecaster.jpg).
It's not the most "proper" of layouts, but it worked. =] I think I have the resistor on the master bypass LED on the wrong lead though.
Alright! I got my valvecaster working nice and quiet from a wall wart! I still have some loose off-board wiring connections though that I need to figure out. And one strange thing I didn't expect...My 12v regulator is putting out 9.4v ??? Am I supposed to have MORE than 12v going in to get it to give me 12v out?
Quote from: bassmannate on November 14, 2010, 09:34:47 AM
Alright! I got my valvecaster working nice and quiet from a wall wart! I still have some loose off-board wiring connections though that I need to figure out. And one strange thing I didn't expect...My 12v regulator is putting out 9.4v ??? Am I supposed to have MORE than 12v going in to get it to give me 12v out?
Yes, 1.5v to 3v more.
If you're using a regulated 12v wall wart try without the regulator. Might be good enough, as long as it's rated to put out enough current.
Quote from: sundgist on November 14, 2010, 12:56:15 PM
Quote from: bassmannate on November 14, 2010, 09:34:47 AM
Alright! I got my valvecaster working nice and quiet from a wall wart! I still have some loose off-board wiring connections though that I need to figure out. And one strange thing I didn't expect...My 12v regulator is putting out 9.4v ??? Am I supposed to have MORE than 12v going in to get it to give me 12v out?
Yes, 1.5v to 3v more.
If you're using a regulated 12v wall wart try without the regulator. Might be good enough, as long as it's rated to put out enough current.
Hmmm...Ok. I have a 12v OneSpot that I had issues with hiss on my last attempt. It's supposed to be regulated, right? Maybe I'll try it again without the regulator chip. I have a universal power adapter that puts out about 15v at the 12v position but it only gives me about 300ma of current which as I recall is the minimum requirement to just run the heater.
if you are running 9 or 12 vdc to the heaters it only pulls 150 ma I hear. If you run 6.3 ac to the heaters 4and 5 and groun 9 it pulls 300ma. So if you got 9 vdc to heaters a 200ma walwart will power the single valvecaster. Hope that makes sense and double check the info but I think its right.
Quote from: kaalaraab on November 14, 2010, 04:23:57 AM
You can try must trusted Renegadrian's layout http://www.aronnelson.com/gallery/main.php/v/Renegadrian/Twincaster+rev+0_11.jpg
Got it, thanks Kaalaraab.
Cheers,
Crusty
I'm having a problem getting this to run on 12 volts? I have a voodoo lab pedal power 2 plus that has two channels that can run at 12 volts 400 ma. when I'm on 9 volts its sounds great when I switch to the 12 volts there is a loud ringing actually some were between a ring and a hum lol. I'm guessing that the 12 volts is regulated since the rest of the power source is.
Is there anything you need to change in then pedal when you switch to 12 volts?
believe it or not I accedentally had the pedal plugged into a 12 volt AC adapter and it sounded great but had allot of buzz?
WOW :o it worked on 12 ac!? weird to be sure! I dont know about the voodoo labs supplies but 12.6 volts regulated should be fine. Nothing has to change. Did you try backing off the gain and volume a bit? Mine sound the best with gain at about 3 o clock and volume just past unity gain. Past that they can start ringing or comptressing in an unpleasnt way but usualy just compressing. How are your heaters wired up?
also did you put a cap across the dc input + - ? I know all my stuff sounds like S@#$ and then i go ..Oh yeah that cap.....
Yah I had the cap across then took it off when I had it on 9 volts I don't know im gonna build the dual caster and try to run that at 12 volts. And its a loud ring IDK ill try to lower the gain but I like the gain lol.
Harold, have seen your voltage booster on diy-layout.... but... what is the IC ? i can't read it anywhere...
Thanks
Quote from: demym on November 18, 2010, 12:08:37 PM
Harold, have seen your voltage booster on diy-layout.... but... what is the IC ? i can't read it anywhere...
Thanks
As Harold already told me, it is in the BOM section. The IC is MAX/LTC1044
Hello everyone. :)
I've been Reading this for what seems like an age now and have
finally got around to building the ValveCaster!!
Thanks everyone for putting all this together!! It's made the cold wet days
of North East England not so bleak. Lol!! Thank you all so much.
First time switching it on and it works. Yay!! Very nice sound indeed although it's about
the same volume maxed as it is when bypassed.
I'm running it at 9v at the moment until I get more time tomorrow to
change it to the 12v regulated supply. I'm also using an Electro Harmnoix 12ax7 as
the 12au7 I bought from evilbay is a dud.
I know I've probably read the answer back somwhere on page 12 :icon_biggrin: but I was wondering how much of a
different beastie will it be with the 12v supply and the 12au7?
Thanks again everyone ;D
the 12au7 has a much more useable sound to my ears. Warmer and smoother definatley. 12 volts should give you a bit more volume. 12au7 will have more volume as wel, less grit though usualy. 12ax7 doesnt even work in this circuite sometimes. Some do some dont. Congrats on your first time success and welcome to the forum! Greg
+1
Thanks Greg and Adriano :icon_biggrin:
I got in touch with the person I got the Dud 12au7 from on eBay
and he's kindly agreed to send me a replacement free of charge! Result!!
What a nice fellow.
As soon as it arrives I'll stick it in with the 12v regualted supply.
I can't wait.
I'll also post some pics and stuff when it's all finished.
I've got a lovely enclosure to pit it in.
Thanks again ;D
That's assuming another dud is not coming towards you in the mail.
We are always hungry of pics!!!
Here's a picture of my VC. :icon_wink:
Sorry for the terrible quality my camera's soooo bad.
http://www.aronnelson.com/gallery/main.php/v/ ???Schematics-etc/DSC00896.JPG.html
I changed it to run at 12v but have noticed that all of my 12v plugs have the wrong polarity.
So I am yet to power her up!! :'(
Am I able to just swap the two wires from the DC socket around?
Is that the same thing or do I need to buy the appropriate 12v wallwart?
Cheers ;D
ooops.
That's not worked.
I'll try again
(//)
http://www.aronnelson.com/gallery/main.php/v/Schematics-etc/DSC00896.JPG.html?g2_imageViewsIndex=1
That looks DAMN GORGEOUS!!! :icon_eek: Congrats...
Nice ! I love those enclosures. Where do they come from?
Hi there.
Thanks for the kind words
The enclosure I got from mike at pedalenclosures.com
they're good quality. I always get the unfinished ones and paint em
myself.
Gonna start work on a triple valve and vibracaster next.
I'll post again when done ;D
Quote from: zambo on November 06, 2010, 01:32:49 PM
I built this pedal using a valvecaster and I think aron nelsons smaxh drive.
Hi, Greg. I put this into my valvy, the result :o Wow, the gain I get is huge and sounds incredible. It results in a really hi gain warm distortion. Know, I had problems with the gain control in the Smash, it did nothing, and since I need a less "metal" and pretty softer overdrived sound, I want to know if fixing the gain problem could get me there or if I need to look for a more soft OD circuit to add to my valvy.
olla, I just finished a (untested, but tubes light up) basic (no tone control), clean (lower Resistor values) valvecaster. I have two questions:
1) currently I have a 7812 along with 100µF Cap in there for voltage filtering and regulation. What happens if I just connect 9 Volts instead of the necessary 12? Will it damage the 7812?
2.) I want to add a boost, I was thinking about a SHO or a mosfetboost. I would like to run the boost via the same voltage supply - so are these boosts doing ok at 12 Volts or MUST I run these boosts at 9 Volt?
How did you guys do it?
thanks!
Just wanted to add my completed valve caster to the pics.
(http://dl.dropbox.com/u/15134989/P5250117.JPG)
@ Kaalaraab, you might try a softer overdrive. That one you have is pretty brutal. On my smashdrive I think I just put a volume pre circuite and used that as the gain ( like turning down your guitar in a way) .You mught try just running a simple boost in front of the valvecaster too. It makes a bigger input signal for the valve to process and throws it into overdrive more. Thats how i started cascading three valvecasters into eachother lol...
@ Blue, You can run 9 volts without changing anything at all. no problems. just make sure if you run them in the same box that your power supply has enought ma to run both fx. I use a 1spot. it has 1700ma. A normal vc uses about 200 ma.Post clips :D
@ Clydeshere, Nice looking work!
@ Clydeshere
HOLY (http://ewsuperstar.forumfree.org/html/emoticons/Cow.gif)
Thanks guys i'm trying to come up with something cool for the bicaster i have on board right now.
Dude where did you get a cow? Thats awesome!
Zambo, just a quick search with google and this page (http://ewsuperstar.forumfree.org/index.php?act=sbextras&CODE=emoticons2&s=) with a lot of smilies appeared...
Hey guys I've been goofing around with the Bi caster and I was getting that really farty distortion that I think I've seen some people complaining about on here.
I put this buffer in front of it and man it smoothed all that bad bass out. Oh I also halved all the capitors on the bicaster circuit. It really smooths the sound out and makes the tone knob actually usable.
(http://dl.dropbox.com/u/15134989/Buffer_TSTransistor.gif)
P.S I've been changing tubes around and trying different combos and really like almost all the tubes with this buffer on it different sounds but all good.
Bye the way thats Dano12's buffer from his great site. and i used the 2N3904
Quote from: clydeshere on December 06, 2010, 02:22:58 PM
I put this buffer in front of it and man it smoothed all that bad bass out. Oh I also halved all the capitors on the bicaster circuit. It really smooths the sound out and makes the tone knob actually usable.
(http://dl.dropbox.com/u/15134989/Buffer_TSTransistor.gif)
P.S I've been changing tubes around and trying different combos and really like almost all the tubes with this buffer on it different sounds but all good.
Sorry for my English, by "in front" you mean, booster first, then valvy? And by "halved" you mean you used all capacitor at half of their original values? Have you tried this on the single Valvecaster? I'm just looking for something to put before my Valvy to give it a warm boost. I will try Omega from runoffgroove.com http://runoffgroove.com/omega.html I hope this would do the trick. But I will give Dano12's buffer a try.
Quote from: clydeshere on December 06, 2010, 02:25:11 PM
Bye the way thats Dano12's buffer from his great site. and i used the 2N3904
Could you post the link to Dano12's site? Thanks.
EDIT: I got the link http://www.beavisaudio.com/
Page 100!
Yah put the buffer before the valve.
And yes some were on here someone suggested to put all the capacitors and half what they are in original schematic of the valvecaster.
im still gonna try some other buffers he has on that same site and also maybe try the fuzz face tone circuit he has on there.
I think were looking for same thing a smooth over drive so I'll let you know what i come up with.
Ok, thanks. Zambo told me abut using Aaron's Smash Drive. I did it and the result was great, but no what I'm looking for. Its a change from natural valvy overdrive to a really hard but warm distortion. I'll try to post soundclips latter.
Yeah Rick, do you remember when it started?! It was just 3 or 4 readers/posters...now it is so popular, its name has spread here and on the net...Nice memories!
Too bad I get here too late. I had to read (and I did it) about 90 pages before start my own Valvy. On the other hand, I learned a lot. :icon_biggrin:
Here's the page with the caps to replace
http://www.diystompboxes.com/smfforum/index.php?topic=63479.1100 (http://www.diystompboxes.com/smfforum/index.php?topic=63479.1100)
I do think it sounds better but i still cant use my neck pickup with either valvecaster or bi caster and it's driving me nuts.
another tube project, I don't know that much about it but it's good to have another schem...
(http://frankyfuzzfire.free.fr/DIY/LAMPES/LowVoltage/TwinPeaksSchematic.png)
Quote from: frequencycentral on December 06, 2010, 05:20:51 PM
Page 100!
Oh, the insanity of it all!
I haven't had time to peruse through the latest 50 pages, so a question: has anyone modded this circuit to act as a simple buffer?
Lol speaking of buffers I've been going through the ones on your site and I like the sound of this one
(http://dl.dropbox.com/u/15134989/Buffer_OrmanOpamp.gif)
At 12 volts it really pushes the circuit. even a little to far lol. Is that vBias a way to control to outgoing volume???
Ok so I think I got it i'll try to draw a schematic later but probably wont have time today plus my computer doesnt seem to like schematic programs.
I'm using this schematic for the twincaster( I've been calling it Bicaster lol)
(http://dl.dropbox.com/u/15134989/twincaster.gif)
replace both C2's with .022uf's
then also put this buffer in front of the circuit
(http://dl.dropbox.com/u/15134989/Buffer_OrmanOpamp.gif)
Sounds great with my humbuckers and my strat that has really picky blues pickups in it.
HAHA Did I kill the thread???????????
NOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO
Quote from: clydeshere on December 14, 2010, 09:29:27 AM
HAHA Did I kill the thread???????????
NOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO
Of course not! I actually want to try building your twincaster with the buffer. I've built a single valvecaster and I love it. I tried it with the buffers, and it sounds great. However, I'm using it with bass, so I'm trying to tighten things up while increasing the gain. Not there yet, but I think I'm close. I think I need to lower the caps as suggested.
I have lowered the caps to .001uf and .002uf . they seem to help tame some of the fizzy that happens when making 2 and 3 tube versions of this. Upping the volts on the plates is good to. adds more to the mids IMHO.
Just thought I would post this. It's a PCB layout for a valvecaster using a PCB mounted socket. Feel free to critique it as it's my first layout ever!
(http://lh5.ggpht.com/_0nZYug53AIk/TQfabjSjP7I/AAAAAAAAAVY/0ep42HTXYow/s912/valvecastersch.png)
(http://lh4.ggpht.com/_0nZYug53AIk/TQfacJucwWI/AAAAAAAAAVc/-5RWEP7cgDE/valvecaster.png)
I wanted to post a transfer but I can't figure out how to get Eagle to export in actual size. I have a PDF printout but I can't post that to Picasa. I may still change a few things like hole and pad sizes since they seem a bit small.
Quote from: clydeshere on December 09, 2010, 09:41:11 AM
Ok so I think I got it i'll try to draw a schematic later but probably wont have time today plus my computer doesnt seem to like schematic programs.
I'm using this schematic for the twincaster( I've been calling it Bicaster lol)
(http://dl.dropbox.com/u/15134989/twincaster.gif)
replace both C2's with .022uf's
then also put this buffer in front of the circuit
(http://dl.dropbox.com/u/15134989/Buffer_OrmanOpamp.gif)
Sounds great with my humbuckers and my strat that has really picky blues pickups in it.
I built a twincaster awhile ago and started to mess with it again. For the most part its stock except for the input caps and both R2's are 1meg running on 9V's. Sounds great but I want to see if I can get more out of it. I was wondering does the buffer start at the input or output of the valvcaster? Just wondering.
Im also thinking of building a triple or quad valvcaster running on 9V. Has anybody built a quadcaster? Zambo?
Quote from: clydeshere on December 09, 2010, 09:41:11 AM
(http://dl.dropbox.com/u/15134989/twincaster.gif)
replace both C2's with .022uf's
then also put this buffer in front of the circuit
(http://dl.dropbox.com/u/15134989/Buffer_OrmanOpamp.gif)
Sounds great with my humbuckers and my strat that has really picky blues pickups in it.
Just getting into the tube based OD/Distortion realm and I really like this schematic. I have a question though.
Wouldn't it be better to run this at 12V? It would increase the headroom (all be it at only 3 V more!!) but more importantly.... it would give the tube heaters the 12V that they are spec'd for.
Quote from: clydeshere on December 08, 2010, 05:36:57 PM
At 12 volts it really pushes the circuit. even a little to far lol. Is that vBias a way to control to outgoing volume???
Could it be done by using a 100k pot after the output capacitor?
Quote from: kaalaraab on December 17, 2010, 01:29:21 AM
Quote from: clydeshere on December 08, 2010, 05:36:57 PM
At 12 volts it really pushes the circuit. even a little to far lol. Is that vBias a way to control to outgoing volume???
Could it be done by using a 100k pot after the output capacitor?
I run mine at 12v. It gives you a bit more headroom. You can run it at 12v just as the schematic shows.
yeah, 12v are the right voltage, I'm looking a way to control the outgoing volume.
I just use a 100K audio taper for volume.
Sorry guy I got something in my eye and have been laid up not aloud to use computer for a couple days. But on the twin caster im running everything at 12 volts. I picked that buffer becuase on Danos sight he says it sound great at 12 volts and i think he was right.
And yes It's just running directly into the input of the twincaster.
@ Pauly, no i never built a quad...lol...although once i set up my voltron ( 3 caster? ) and put a single vc after it for a volume/lead boost. The single was running on 60 ish volts. I sounded so dang beefy i just started building the voltrons with a 45 volt voltage multiplier in them using lt1054 chip. It gets way to much gain if you want it. If you want a realy gainy pedal I built a trainwreck preamp in a stomp box. It uses 12ax7's and runs on 45 volts ish. You can use au7's and run it on 9 or 12 though and it still sounds pretty good. There is a thread on here somewhere i started. I been over on ax84 learning how to build amps latley. Sorry for the lag in response. Y'all can pm me if you want to ever. Cheers. Greg
here is the tw pedal. http://www.youtube.com/watch?v=T-sNT_xjJ9E
@ Zambo. Yeah, I hooked up two more tubes to my twincaster, running at 9Volts and it sounded the same. Wasnt bad but it didnt add really any more gain but I was thinking about using a voltage multiplier and seeing if that helps. I really like my twincaster as is but Im always looking to try something new.
i have found that 40 to 60 volts really kicks the gain up to a nice usable hard rock distortion. I posted this so sorry if I am repeating...its a three tube running at 45 ish volts . http://www.youtube.com/watch?v=YhyyYjY5CgA I gigged with this and loved it. you have to tweak the highs with .001uf caps from plate to ground on the first 2 stages. All the coupling caps are around .002uf as well. Tweak to taste of course. The third tube really makes a difference i think. Its more of a master volume type of stage. lets you crank the first two and then control the volume with the third. for what its worth. Cheers, Greg
Quote from: zambo on December 22, 2010, 10:31:56 PM
I posted this so sorry if I am repeating...its a three tube running at 45 ish volts
Hi, Greg. Do you have de link to the original post?
Quote from: zambo on December 22, 2010, 10:31:56 PM
you have to tweak the highs with .001uf caps from plate to ground on the first 2 stages. All the coupling caps are around .002uf as well. Tweak to taste of course. The third tube really makes a difference i think. Its more of a master volume type of stage. lets you crank the first two and then control the volume with the third. for what its worth. Cheers, Greg
What happened with the second switch? Does it integrate the second and third tubes? Do you use a volt multiplier inside the stompbox to get 45 volts?
I've been fooling around with Smash Drive and Omega pre amp before de Valvy, I think I'm getting close to the sound I'm looking for. Now I'm going to try the Voltron to see if I have more luck there.
I must have posted in this thread somewhere. I have built porbably 5 or 6 versiond of this pedal. This one is my fave. I used the voltage multiplier i found in frequency centrals thread for the murder one or the superfly amps. They work well but take some space. I use the lt1054 from small bear electronics and it works great. You really have to tweak the highs on this design but its sounds pretty good if you are stuck on tubes...you could use more voltage and do it with two tubes and or use 12ax7's instead. They are pretty harsh to my ears sometimes with lower voltage though. I use 12au7's all the time now for this design. The first switch is global bypass or on. the second switch is 1 tube or 3 tubes. It works pretty well although if i were looking for a pedal that did some distortion and more distortion I would make the second switch be 2 tubes or 3 tubes for a choice instead. Let me know if you need any help. I try to check in but if you dont get a response, private message me and i will see it in my email at home. if you have a twincaster and a valvecaster you can always just run them in series and see what it sounds like as well. I just stuck it all in one box and gave it convenient switch choices. Cheers, Greg
What mods should i make on original (http://www.aronnelson.com/DIYFiles/up/12AU7-6111_Valve_Caster_Summary_Rev002.pdf) valvecaster/dual valvecaster
to make the overdrive less distorted and more smooth.
Like this:
http://www.youtube.com/watch?v=qB0Cog7WIsg
:) I've just built the ValveCaster and love the sound ;D However, instead of problems with hiss, I have problems with hum!! I have a regulated power supply and still get the same hum even with a 9 volt battery! Is it an earthing issue?? What tricks could I employ to cut the hum?? Thankssss :)
Sorry about that! Actually I've found that there's no noise with the battery now but a hum with one regulated power supply and an enormous hiss with another supposedly regulated supply!! Can't believe there's so much variation out there! Sorry for messing up the thread.........
I build twin valvecaster today. Sound is absolutely amazing with two 12at7.
But the sound is very muddy, with the tone knob to the may, there is still to muddy, dark.
How can I increase the brightness?
And one biggie:
If i don't play, there is hiss. When i play, there is absolutely no hiss, very nice sound, but when i stop playing hiss comes back like 2 seconds after i stop playing. It has nothing to do with touching the strings
What is happening?
Here is how it sounds: Tone is to the max and it is still too dark. Hiss comes delayed.
http://www.youtube.com/watch?v=my_RZtMc9KE
Why?
For dark sound, earlier in this tread the adviced was given to try smaller values for the output caps. Even include a switch between caps to have two different kind of sound.
For the hiss, I really can't tell whats happening, It sounds to me like some kind of external sign is being amplifyied, but I'm not sure of it. Sorry.
yah the hiss Is probably your power source I had to buy a regulated power supply to get rid of it.
As far as the darkness cut the 2 input caps in half and try the buffer I put up on page 100 i think works great.
The only way i could get my valvecaster and twincaster to be quiet with NO hiss or hum was to use old power supplies from laptops...
Quote from: Jule553648 on December 25, 2010, 07:55:51 AM
If i don't play, there is hiss. When i play, there is absolutely no hiss, very nice sound, but when i stop playing hiss comes back like 2 seconds after i stop playing. It has nothing to do with touching the strings
Sounds like a large cap is being drained while you are playing, and then filling back up when you stop playing. Where's the schem for a twin valvecaster anyway?
Quote from: merlinb on December 26, 2010, 09:26:31 AM
Quote from: Jule553648 on December 25, 2010, 07:55:51 AM
If i don't play, there is hiss. When i play, there is absolutely no hiss, very nice sound, but when i stop playing hiss comes back like 2 seconds after i stop playing. It has nothing to do with touching the strings
Sounds like a large cap is being drained while you are playing, and then filling back up when you stop playing. Where's the schem for a twin valvecaster anyway?
(http://www.beavisaudio.com/Projects/ValveCaster/twincaster.gif)
Are you quite sure about the connection between the 2nd and 3rd tube? Is that how you've built it or is that a drawing error ('cause it ain't right!)?
No. I build that connection correct - to the second pin.
Quote from: Jule553648 on December 26, 2010, 12:34:13 PM
No. I build that connection correct - to the second pin.
That schem has an error. (Someone really should have removed it from wherever you found it!)
The 2nd and 3rd stages are not connected together properly, which is causing your delayed hiss problem. It should look more like this (you can ignore the switch and extra tone/vol pots if you want):
(http://i386.photobucket.com/albums/oo302/Smiler/TSschem-1_switchable.jpg)
(http://thumbnails26.imagebam.com/11259/5165a3112587439.jpg) (http://www.imagebam.com/image/5165a3112587439)
;D ;D ;D ;D ;D ;D ;D ;D ;D
hello people. i recently built a valvecaster. (single tube). i thought i had it working but apparently i don't after hearing some sound clips. i am only getting a gain boost over about 8 out of 10 on the gain knob, and the signal completely drops off lower than 5. i thought the circuit was just weird but apparently it should be almost transparent at gain 0.
the only problem i can see is maybe the gain pot, it's a futurlec panel mount, and it has a wiper swish. i have some proper pots from smallbear but no 50k. could i sub a different value to test this?
or if this is a common problem please let me know what i am doing wrong.
thanks, joe.
How to bypass this pedal?
Can I use 2pdt and just bypass from one input jack to another?
yes.
Hi all,
I found this site and thread just over a month ago.
I followed the schematic posted at the start and 'breadboarded' the circuit.
It sounds amazing. it adds warmth and a little crunch to my solid state bass rig but in front of my Ampmaker WF55 it sounds fantastic. ;D
So I'd just like to say thanks to all the contributors who have made this possible.
Next thing is to experiment with different anode resistances as suggested in the thread and then box it all up.
just got all the parts and ready to build! All I have to do first read through 102 pages of this thread :icon_eek: ;D
pazuzu you can use almost any pot i think but i would stick to like 100k . I use that one all the time. no problems.
actually, I've got my own minor problem with the circuit. it's all breadboarded and whatnot with stock parts from the normal Valvecaster scheme, and I'm running it off of 12V regulated DC from my power brick. The problem is that the gain pot doesn't give me all that much Gain! There's only the tiniest bit of overdrive when the Gain pot is turned all the way up. I'm alligator-clipping all the pots into the circuit, so I thought that mayhaps that they were introducing some resistance in there that might be limiting voltage to the Cathode on the first tube, but that seems like a pretty hokey answer there. I'm looking to buy a Multimeter ASAP for this and other projects, so I can't give voltages right now, but by any chance could anyone give me the voltage and Current values that SHOULD be between the connection from Tube 1's cathode to ground for the both extremes of the pot at values of 0Ω and 50KΩ?
alternatively I was thinking of modding this thing with a Tillman boost or a MOSFET booster (parts on the way! ;D ) in front of it and adding some Cathode Bypass caps to one or both stages, and that should hopefully give me shittons more gain and overdrive. WHICH IS WHAT I WANTZ!!!
Quote from: frequencycentral on June 05, 2008, 04:43:34 PM
Pin 1: 3.02v
Pin 2: -0.518v
Pin 3: 0.00v
Pin 4: 0.00v
Pin 5: 11.97v
Pin 6: 8.21v
Pin 7: -1.285v
Pin 8: 0.00v
Pin 9: 5.91v
DC power in is reading 11.99v.
Gain at maximum.
Edit: My gain pot is 100K not 50K.
Hi, Astronaurt. Here are the voltages taken and shared by Rick earlier in this tread.
I think the resistance must be between 0 and 50k in any way
I've been trying with Omega from runoffgroove.com http://runoffgroove.com/omega.html In front of my valvy switching it with a second 3pdt, it sounds great.
@ Astronuart- This thing doesnt give all that much distortion. It does provide enough boost to overdrive the input of an amp though. So while it wont really be a distortion pedal, It will knock a valve jr or a blues jr or something of that nature into the next level of OMG distortion. If you want a distortion pedal then yeah, the tillman boost is a good one to put in front of it i hear or an sho. I just run one into the other using three of them but really, there are better design for distortion. This is nice for what it does though..my 2 cents, G 8)
Quote from: zambo on January 02, 2011, 01:02:14 AM
pazuzu you can use almost any pot i think but i would stick to like 100k . I use that one all the time. no problems.
thanks, i am going to try it tomorrow than. thanks to the guy who quoted the voltages on the pinout. i will test that tomorrow as well.
Quote from: goatboy on December 24, 2010, 04:34:23 PM
Sorry about that! Actually I've found that there's no noise with the battery now but a hum with one regulated power supply and an enormous hiss with another supposedly regulated supply!! Can't believe there's so much variation out there! Sorry for messing up the thread.........
when using power supplies, whether regulated or not, I always connect a 1 or 2 ohm 3 watt resistor in series and a large electrolytic to ground (i.e. 1,000uF) to the power line. It acts like a filter
in between the power in and the fx board?
Quote from: pazuzu on January 04, 2011, 04:36:28 PM
in between the power in and the fx board?
at the point after the power hits the board. the values aren't critical. the resistor just has to be at least 3 watts and can be from 1 to 5 ohms. usually a 1000uF should work but I would use a higher cap value if using higher voltages.
(http://i782.photobucket.com/albums/yy105/tallpall7/powerfilter.jpg)
oh ok i see, resistor between the v+ and the board and then the cap run off the same junction to ground. could this clean up some of the back ground noise on the valvecaster in theory?
Quote from: pazuzu on January 04, 2011, 06:35:21 PM
oh ok i see, resistor between the v+ and the board and then the cap run off the same junction to ground. could this clean up some of the back ground noise on the valvecaster in theory?
it works well for me. YMMV though. noise comes from a lot of sources like house wiring, electric motors, dimmers, compact fluorescent bulbs, neighbor's invisible fence, etc.
yep. my house was built in the 40's...so, yeah. the wires are solid copper with cloth insulation. :icon_rolleyes:
Quote from: Renegadrian on February 17, 2008, 08:40:26 PM
Here's version 0.4 - removed unnecessary strips and optimized it again, tone now working the right way.
Should work...
Next is the MVT redrawn by me, it displays better in this layout...Credit obviously to the makers of the previous schem and layout...
(http://img183.imageshack.us/img183/9308/valvecasterv04yu8.th.jpg) (http://img183.imageshack.us/my.php?image=valvecasterv04yu8.jpg)(http://img301.imageshack.us/img301/3672/marshavalvetubeop6.th.jpg) (http://img301.imageshack.us/my.php?image=marshavalvetubeop6.jpg)
BTW, sorry for my ignorance...what is a SHO?! ???
Also, I know that there's ORMAN Tube Driver that's working on 9-12V, I found some good layout I'd be posting here...
Hello,
I am new here, but I have a question about your layout.
What does it mean when you say "cut track under C1"?
And just so I am sure, all of the 'to ground' wires need to connect to each other some way or another right?
sorry for the noob questions, but this is only my 2nd build.
And as far as I can tell, all of the caps are non-directional. If I already have these capacitors, but they are directional, which way should they be going?
I only ask b/c I went to the Radio Shack and all they had were electrolytic caps in those values.
Most of all, thanks for the layout, I can't wait to get started on it.
-Bill
HI, WELCOME.
cut under c1 means that the copper under the c1 capacitor has to be cut..so there is a gap in the copper trace..
electrolytic capacitors have a grey side on the diagram..this is the negative side...
on the valvecaster there are no electrolytics...so your ok with straight forward caps ok...
yep all grounds to each other...
with the marsha there is one electrolytic cap..all others are normal ok...
elecrtrolytic caps come in 'uf' values meaning micro farad..
other caps uf/nf/pf...but not polarized ok..not positive and negative....
good luck.
Quote from: deadastronaut on January 08, 2011, 07:06:55 PM
HI, WELCOME.
cut under c1 means that the copper under the c1 capacitor has to be cut..so there is a gap in the copper trace..
electrolytic capacitors have a grey side on the diagram..this is the negative side...
on the valvecaster there are no electrolytics...so your ok with straight forward caps ok...
yep all grounds to each other...
with the marsha there is one electrolytic cap..all others are normal ok...
elecrtrolytic caps come in 'uf' values meaning micro farad..
other caps uf/nf/pf...but not polarized ok..not positive and negative....
good luck.
Ok, so if I am using a generic perfboard, then it shouldn't matter right.
This is my favorite type of layout. What software is it? My first project had the same type of layout software.
perfboard yep...thats ok. i thought you were using veroboard..(copper clad on one side)
the software for making these layouts is called diy layout creator..
its free to download. from bancika, there are 2 versions...version 1 is what has been used on those layouts ...great bit of software!.. :icon_wink:
http://diy-fever.com/software/ (http://diy-fever.com/software/)
Cool, thanks for the link.
This an awesome thread btw. I have read over about 1/2 of it and I can see that there is a lot of room for customizing this little gem. Once I get my current project in an enclosure, I plan on spending some time getting to know about tubes. In the end, I hope to be able to make my own tube amp head. Just out of curiousity, would it be possible to make a 'tube locust' out of one of those large tubes that are used in tube amps? Sorry if this is off topic. Feel free to point me to a different thread.
-Billy
Quote from: Harold on November 10, 2010, 03:57:01 AM
Quote from: Astronaurt on November 10, 2010, 03:07:46 AM
I'm new to the site, so Idk if I'm using the search function right! Could I get a link for the Tube Star?
http://www.diystompboxes.com/smfforum/index.php?topic=74888.0
Quote from: Astronaurt on November 10, 2010, 03:07:46 AMI'm not particularly interested in voltages above normal stomp box level, I'm building stuff so I can put on my Pedal Board and hook it up to my power brick mostly!
You can use a voltage booster inside your pedal, like this one:
(http://diy-layout.com/diyl/42/render)
http://diy-layout.com/42
Quote from: Astronaurt on November 10, 2010, 03:07:46 AMI also just looked up the Tillman circuit cuz I hadn't heard of it before and it sounds like an idea worth checking out. If I want to adjust the gain on that though, I'm thinking I should sub a pot for either R3 or R4.
I've also put the Tillman preamp in front of my ValveCaster and like it al lot! I could not get the J201 to function correctly so I replaced it with an 2N5485.
(http://diy-layout.com/diyl/34/render)
http://diy-layout.com/34
I was wondering about this voltage booster. If it was place directly in front of the Valvecaster, would it work properly, or would it blow a 12AU7 tube? I am new to this stuff and I am just doing some research while I get all my parts lined up. Or, say you stopped at around 30V to avoid any shock hazards. Would this give a different sound?
Take cares,
Bill Blackburn
morwe voltage on pins 1 and 6 equal more volume and more mids. the overall sound is a lot more punchy. I like them at around 45 volts or so. Just make sure the heaters stay at normal voltage. You have to run the plate resistors seperate from pin 5.you also have to take component values into consideration. If you havent ordered parts yet, get higher voltage caps and 1/2 watt resistors. Almost the same price . Have fun, G
good point. Do you have a layout for the 45volt version with voltage booster? Also, what are the red squares with a red dot inside of them? What component does it represent? Soon for the noob question.
Bill
Quote from: BarnyardBill on January 09, 2011, 03:12:44 PM
good point. Do you have a layout for the 45volt version with voltage booster? Also, what are the red squares with a red dot inside of them? What component does it represent? Soon for the noob question.
Bill
cuts!... :icon_wink:
I made a little rectifier circuit (for the original pedal of this thread) and it is now 1000000% quiet!! No 50-100Hz hum whatsoever!!
The reason why I`m posting this now is because I KNOW there are people out there who built this pedal and are struggling with bad wall warts.
Connect this simple (yet damn effective) circuit between the crappy wall wart and the pedal, and all the demons will dissapear.
(http://img94.imageshack.us/img94/4394/img1072yo.jpg)
Notice the voltageregulator is a 12V regulator. Heck I even used it on 9V and they both sounded wonderful!
(http://img96.imageshack.us/img96/7814/superrectifier.jpg)
And here is a videoclip with studio recording.
http://www.youtube.com/watch?v=ZDNPehH2VZQ
Just wanted to share that with yall.
Quote from: deadastronaut on January 09, 2011, 03:26:48 PM
Bill
cuts!... :icon_wink:
[/quote]
ok, and one more noob question. For the diodes, the end with a black bar is positive or negative? I assume its negative, but just to make sure.
Bill
ha ha....yep negative bar.......triangle positive... :icon_mrgreen.
look forward to hearing this project!....looks good!. ...dont worry i'm still a noob too!.... :icon_cool:
Quote from: BarnyardBill on January 09, 2011, 11:58:14 AM
Quote from: Harold on November 10, 2010, 03:57:01 AM
Quote from: Astronaurt on November 10, 2010, 03:07:46 AM
I'm new to the site, so Idk if I'm using the search function right! Could I get a link for the Tube Star?
http://www.diystompboxes.com/smfforum/index.php?topic=74888.0
Quote from: Astronaurt on November 10, 2010, 03:07:46 AMI'm not particularly interested in voltages above normal stomp box level, I'm building stuff so I can put on my Pedal Board and hook it up to my power brick mostly!
You can use a voltage booster inside your pedal, like this one:
(http://diy-layout.com/diyl/42/render)
http://diy-layout.com/42
Quote from: Astronaurt on November 10, 2010, 03:07:46 AMI also just looked up the Tillman circuit cuz I hadn't heard of it before and it sounds like an idea worth checking out. If I want to adjust the gain on that though, I'm thinking I should sub a pot for either R3 or R4.
I've also put the Tillman preamp in front of my ValveCaster and like it al lot! I could not get the J201 to function correctly so I replaced it with an 2N5485.
(http://diy-layout.com/diyl/34/render)
http://diy-layout.com/34
I was wondering about this voltage booster. If it was place directly in front of the Valvecaster, would it work properly, or would it blow a 12AU7 tube? I am new to this stuff and I am just doing some research while I get all my parts lined up. Or, say you stopped at around 30V to avoid any shock hazards. Would this give a different sound?
Take cares,
Bill Blackburn
You only want the high voltage on the plates which are pins 1 and 6. The heaters are still looking for around 12v. 9v on the heaters is fine if that's what you're using.
Someone please chime in. I've only ever messed with 12v on this. If you're using 9v, would you use the center tap on the heater and just over volt them? Someone please explain for our friend a bit more than I can.
Quote from: zambo on January 09, 2011, 01:51:52 PM
morwe voltage on pins 1 and 6 equal more volume and more mids. the overall sound is a lot more punchy. I like them at around 45 volts or so. Just make sure the heaters stay at normal voltage. You have to run the plate resistors seperate from pin 5.you also have to take component values into consideration. If you havent ordered parts yet, get higher voltage caps and 1/2 watt resistors. Almost the same price . Have fun, G
Can you overvolt without other modifications than the separate heater power?
Or you must change some resistors?
Anyone tried putting a lovepedal eternity boost in front of the valvecaster? Or, does it sound better with more tubes in series?
just the heaters. You also really need to make sure caps are rated for the voltage and using 1/2 watt resistors is good too. I like to double the cap voltage I.e. 45 volt pedal made with 100 volt caps etc. Cant be to safe ;)
Re: High Voltage Valvecaster.
Check out Garth's Valvecaster layout and pics on pg. 77.
Check out my thread if you're interested in a valve caster/ tube cricket hybrid amp. Very interesting (thanks srv for your contribution).
http://www.diystompboxes.com/smfforum/index.php?topic=89073.0
Feel free to add anything. :icon_idea:
That looks pretty neat. Unfortunately I am having some difficulties getting my Valvcaster working properly. I am going to have to start reading voltages to see where the problem is. I have a feeling it could be my capacitors that are running in parallel b/c I dont have the .047uF cap so I used 2 x .022uF in parallel to make one .044uF. Is that correct?
Thanks,
Bill
P.S. My tube is lighting up, so I at least have something correct
that is correct. If you have doubts, use just the .022uf. They sound really good. Sometimes I use .002. They sound good to if you are going for a more distorted sound.
Hey, I 'm pretty stoked. My small breadboard was so hard to work with so I switched circuits and tried the "Triode Triode". I am 99% sure that it is working. I mean it is a subtle difference in sound and I am not using the full 12V although I am tempted to work something out with my wall wart. After trying for 1 full day I have finally got some juice flowing through. One BIG problem was that I wasn't wiring the 1/4" jacks correctly. Go figure. I bet my Tubecaster was correct all except the jacks. :P Oh well. Obviously I need the practice.
It seems that cap values are not so important as long you have something similar. Although, I would not go willy nilly with a high voltage scheme.
I really need to make a decision on a few enclosures and go ahead and order them. personally, one of my favorite I have seen is the small enclosure with the tube sticking out.
Thanks a lot,
Bill
Quote from: Renegadrian on February 03, 2010, 08:59:07 PM
Quote from: zambo on February 03, 2010, 08:05:29 PM
Well, Thank you very much! :icon_redface: I will take those as great compliments! I am trying to figure out how to run these at 30 volts or so. I know the heater only gets 12.6 max so where do I hook up the 30 volts? To the anodes? I am looking for a schematic but I cant tell the mechanics of it from vero board layouts. ( iwish I wasnt such a visual person). Any one have a clue? ( its a rhetorical question, I know Renegadrian knows... ;) )
Yeah, more voltage goes to the anodes - if you use my layout here (http://www.aronnelson.com/gallery/main.php/v/Renegadrian/Valvecaster-no-tone+elc3.jpg.html?g2_imageViewsIndex=1) (or follow to get the idea) you see a red wire that gives power to two res (R2-R3) that go to first and second anode (pins 1 and 6) and then on the same line pin 5 (one of the heaters) is connected - to apply different voltages, you can use that very same layout, just connecting pin5 to the +12V and whatever upper voltage you want to that row with the red wire!
Renegadrian and Zambo,
Ok, I think am following this explanation of how to use higher voltages with this layout(here (http://www.aronnelson.com/gallery/main.php/v/Renegadrian/Valvecaster-no-tone+elc3.jpg.html?g2_imageViewsIndex=1)) like you mentioned. If I start with a 30V power supply, could I use a 12V regulator placed before pin5 and be ok?
I am just getting some ideas on how to implement what you are describing.
I play a lot of jazz stuff, so I really like the subtle tube overdrive sound.
Also, I saw someone mention that 12AU7 runs optimal at 100V. Has anyone tried such high voltage with this? I think that would be more for power amps and such.
Bill
Sure you could. That should work fine. I am nor sure about vero cause I am not very good at visualizing it. If you have a 30 volt supply run 1 wire off of it to a 12 volt regulater trhen to pin 5 and ground pin 4. Pin 9 is not used. Run another wire to pin 1 through a 100k resister in series. Run another wire to pin 6 with a 220k resistor in series. An easier way though in my opinion is to use a voltage multiplier, They are quite simple and you can make more or less volts to suite your needs. Frequency Central ( Rick Holt ) Has made some small and nicley laid out ones. I have run them up to about 100 or so volts. I think 30 to 60 is more than adequate though. You have to judge for yourself. When you are using more voltage you should put a resistor on pins 3 and 8 to ground for the cathode. 1.5 k is pretty standard. You could also just never turn your gain knob all the way to 10 but resistore are cheap right?
Alright. Cool. Do you usually put the voltage booster inside the same enclosure, or do you think it is too large ?
OK, I built the valvecaster today and left out the tone pot. I used a 12V wall wart for pin 5 and a 30V wall wart for the heaters pin 1 & 6. Then I connected both of the wall warts ground to the ground on my breadboard. It was giving me some really strange noises when I had the gain and volume up. I mean if I turned the knobs on my guitar it making noises like a wave generator or something. Then, I started smelling something burning and I think I may have blown both my wall warts. Does that make any sense electronically. I will have to find another wall wart and try again. My room really smells like burnt electronics now. (cough cough)
-Bill
You used 30V for the heaters?? Since they are connected in series it needs 12,6V. Correct me if I`m wrong
well, I am not sure. All I know is that my wall warts do not read on my voltmeter. I rigged up another one and it is working, but I get some muddy notes and even sounds like some lower octaves are sounding too. Also, a very loud hum in the frequency of B. Still working on it :).
Quote from: BarnyardBill on January 15, 2011, 02:42:42 PM
Does anyone have any ideas about why I am not getting a distorted sound? Do I have the circuit wired wrong?
As I know, generally this project is a booster much more than an overdrive, and overdrive depends on several circumstances. For instance, when I first built mint, I was using an EH 12AT7, it sounded pretty harsh for me, so I changed to EH 12AU7, it was ok, with a light yet warm overdrive. I try a RCA Clear Top, no overdrive, but a really good and warm sound. On the other hand, check the gain pot, it could be not working well.
kaalaraab,
that is reassuring to hear that you seem to be getting the same results as me. The only way I get any overdrive/distortion is by changing capacitors and it is not a distortion that I would ever want to use. Anyway, I just heard some of the samples on youtube and a lot of them had distortion. I guess they used an amp or pedal for that? I personally prefer the warm boost and tone enhancement like you described. I do have a LARGE amount of hum and noise from my wall wart, so I hope to be able to clean that up with one of the rectifier circuits around. Do you think a rectifier circuit would be better than a 12V regulator?
Thanks,
Bill
Quote from: BarnyardBill on January 15, 2011, 09:11:39 PM
I guess they used an amp or pedal for that?
I've been trying with boosters and buffers in front of my valvecaster inside the same stompbox. By now, Omega, from runoffgroove.com is which I liked most, in gives a really nice boost That overdrives the valvy creating a warm distortion. I'm using a 3pdt switch to by pass it.
Quote from: BarnyardBill on January 15, 2011, 09:11:39 PM
Do you think a rectifier circuit would be better than a 12V regulator?
I have a very lousy wall wart that throws between 18 and 22 volts. With the regulator suggested by Renegadrian ( http://www.aronnelson.com/gallery/main.php/v/Renegadrian/regulator.gif.html ) I have no hum and any other problem with it.
Quote from: BarnyardBill on January 15, 2011, 02:42:42 PM
OK, I built the valvecaster today and left out the tone pot. I used a 12V wall wart for pin 5 and a 30V wall wart for the heaters pin 1 & 6. Then I connected both of the wall warts ground to the ground on my breadboard. It was giving me some really strange noises when I had the gain and volume up. I mean if I turned the knobs on my guitar it making noises like a wave generator or something. Then, I started smelling something burning and I think I may have blown both my wall warts. Does that make any sense electronically. I will have to find another wall wart and try again. My room really smells like burnt electronics now. (cough cough)
-Bill
instead of using 2 wallwarts you can use just one with a voltage divider to pin 5. It's pretty easy, it's just 2 resistors. you can use this calculator to get 12 volts from 30V http://www.raltron.com/cust/tools/voltage_divider.asp you connect pin 5 to where the 2 resistors meet. the other side of resistor 1 taps into +30V. the other side of resistor 2 connects to ground.
(http://www.raltron.com/cust/tools/images/voltagedivider.gif)
did you make sure both walwarts are dc, and also that they are tip negative? I ve seen a couple guys i built this pedal for plug in the wrong polarity adaptor and smoke the regulater on the dc jack. It smells.... The tubes usualy lived through it though.
I am still getting some really strange sounds from my valve caster. With the 47nf caps that are suggested, I get a really loud buzzing. Not a wall wart buzz, but a REALLY loud buzz. So, i switched to 10nF and then it becomes usable, but I still get some LOUD buzzing when I turn the volume pot on my guitar. COuld this be caused by loose breadboard parts? I probably need to invest in those little alligator clips for this type of thing. Anyways, any help in appreciated.
zambo,
yeah I a pretty sure I had them oriented right. Probably something I plugged in the wrong spot on the breadboard.
thanks,
bill
instead of using 2 wallwarts you can use just one with a voltage divider to pin 5. It's pretty easy, it's just 2 resistors. you can use this calculator to get 12 volts from 30V http://www.raltron.com/cust/tools/voltage_divider.asp you connect pin 5 to where the 2 resistors meet. the other side of resistor 1 taps into +30V. the other side of resistor 2 connects to ground.
(http://www.raltron.com/cust/tools/images/voltagedivider.gif)
[/quote]
That's a good idea. I have a 15V Toshiba wall wart that seems pretty descent and also puts out 3A. I am gonna try this right now actaully.
are your wall wart's regulated?
Quote from: zambo on January 15, 2011, 11:34:38 PM
did you make sure both walwarts are dc, and also that they are tip negative? I ve seen a couple guys i built this pedal for plug in the wrong polarity adaptor and smoke the regulater on the dc jack. It smells.... The tubes usualy lived through it though.
Ok, I made the voltage divider and when I connect it to my circuit, the voltage on pin5 drops out? Do I need to connect pin 4 and/or pin 8 to the voltage divider's ground? I can't figure it out.
-Bill
Quote from: BarnyardBill on January 16, 2011, 09:06:18 PM
Quote from: zambo on January 15, 2011, 11:34:38 PM
did you make sure both walwarts are dc, and also that they are tip negative? I ve seen a couple guys i built this pedal for plug in the wrong polarity adaptor and smoke the regulater on the dc jack. It smells.... The tubes usualy lived through it though.
Ok, I made the voltage divider and when I connect it to my circuit, the voltage on pin5 drops out? Do I need to connect pin 4 and/or pin 8 to the voltage divider's ground? I can't figure it out.
-Bill
pins 4 & 8, the wallwart ground, and the voltage divider ground should all be connected to common ground. when you remove the tube pins 1 & 6 should read near 15V (or wallwart voltage) and pin 5 should be 12V. when you see that, you've got it. to check to see if the tube heater is fried you can check for resistance between pins 4, 5, and 9. If you see a low ohm reading the heater is still good.
i measured the ohms and got between 6 and 13 Ohms for the reading. I might just have to order a few voltage regulators and sit tight for a while. I think I have become obsessed with this. Maybe I will go back to the fuzz pedal I made and then come back to this. After all this is only my 2nd project. Maybe I am expecting too much. So far so good. I think I am beginning to understand how the tube works. Here are my learnings so far: Pin 1 and 6 should read the full voltage. Pin 4 and 8 should be grounded. Pin 5 is the heater and should be at 12V(9V) . So, that leaves Pin 2, Pin 3, and Pin 7. These pins usually have a reading around ~0.00. Feel free to explain this relationship of the pins to me. Is this acting as two triodes?
Quote from: BarnyardBill on January 16, 2011, 10:10:53 PM
i measured the ohms and got between 6 and 13 Ohms for the reading. I might just have to order a few voltage regulators and sit tight for a while. I think I have become obsessed with this. Maybe I will go back to the fuzz pedal I made and then come back to this. After all this is only my 2nd project. Maybe I am expecting too much. So far so good. I think I am beginning to understand how the tube works. Here are my learnings so far: Pin 1 and 6 should read the full voltage. Pin 4 and 8 should be grounded. Pin 5 is the heater and should be at 12V(9V) . So, that leaves Pin 2, Pin 3, and Pin 7. These pins usually have a reading around ~0.00. Feel free to explain this relationship of the pins to me. Is this acting as two triodes?
the relationship of the pins is beyond my knowledge. I just make circuits from layouts. I found out when working with tubes I always have several on hand because some might be bad. I've purchased tubes and some of them didn't work, especially the ones off ebay. when 2 or 3 tubes don't work in the circuit it lets you know something in the circuit is not right.
@ Bill. Yes the tube is two triodes. Pin 1 is anode ( plate ) for triode one. Pin 2 is grid ( where the signal comes in. I consider it the input ) Pin 3 is the Cathode ( where all the juice flows to). The gain knob is a variable resistor between the cathode and ground. More resistance equals less juice getting to ground ( roughly ). 4 and 5 are heater. 6 is anode ( plate ) for second triode. 7 is the second grid ( where the signal goes in again ), 8 is the second cathode. Technicly you could put another gain knob here but it would only give you less gain in this instance. Grounded cathode is max gain. Pin 9 is heater ground when you are using 6.3 volt ac heater current. 6.3 ac goes to pins 4 and 5 9 being the grounded pin.
Current flows between anode and cathode. The screen is in between them. The guitar signal is an ac signal. It causes the plate voltage to fluctuate in time with the guitar ac grid signal. As the 9 volt plate voltage fluctuates it creates a bigger ac signal. The decoupling cap ( the cap from pin 1 ) blocks dc signal but lets the now bigger ac signal through to the next grid where the same thing happens. The next decoupling cap ( off pin 6) keeps the dc from flowing on to the next thing in the chain. The size of the decoupling caps helps shape the amplified signal by limiting how much low end is re amplified. Every stage adds both highs and lows. Multiple stages require attenuation of the lows and highs or you get nasty feed back and oscilation. The input cap stops dc from flowing out the grid to your guitar. If the dc reaches your guitar tyou will have scratchy sounding volume pots. Hope this helps explain how this thing works. I dont know a lot about tubes and stuff but what i do know I learned from the smart guys on here. Good luck, G :icon_smile:
that helped, thanks a lot for the explanation. I set up the valve-caster(no tone knob) circuit today and I had one strange thing happening. The volume and gain knobs didn't work? I am not sure why this happened. I double checked my circuit and did't see any errors? However, I was able to pick up a 7812 today, so that helped with the wall wart. Any ideas about why my pots aren't working?
Bill
Edit: never mind, I had some wrong connections. Now I can try changing the coupling caps to make it sound better. I guess different humbuckers can require different capacitor sizes? thanks again.
Quote
I guess different humbuckers can require different capacitor sizes? thanks again.
The .01uF input cap is too low for my tastes so I used a .22uF. If you want a fatter tone with more bass you can use a .047 or .1uF at the input. I used a .22uF because I play bass and guitar. since the signal goes through the caps the brand will influence the sound. orange drop caps sound great if you play a lot of rock. I prefer the sound of Mallory 150's and Nichicon polyester films
(http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=42416&g2_serialNumber=2)
I used this layout on mine and I think the volume and gain knob are somehow reversed. It's tough to tell sometimes. The cap values I like so far is 1pF for C1, 7pF for C2 and 68pF for C3. This way I eliminate the scratchy static that comes through when I strum. They are the ceramic caps from an assorted pack at radio shack. I am assuming that if the numbers aren't 3 digits then they are in pF. Also, my tube is an RCA that is marked for "noise and micro-phonics". I still can't believe the amount of buzz that my wall wart is letting through.
Do you ever get some really hissing noises when you change to different capacitors? Sometimes if I have gain and volume all the way up, it makes such a bad hissing noise until I turn it down. I am tempted to go back and try the tube circuit with only the volume knob. It seemed to behave better for me.
Bill
i believe on those caps you have to look at the numbers as a code. The code will tell you what size they are. As far as hissing, Mine are pretty quiet. I use a .002 on the coupling caps a lot of times when running multiple valves in series. For a plain valvecaster I run .01 and .0047 for input and coupling caps. I never turn it all the way up as they sound bad to me that way. Volume at 3/4 and gain about the same is my fav. Picofard sized caps i think are to small for any good sound. Bigger caps like stock value sound awesome on single coils. thats my opinion what its worth :P
Bill, those values are way out of standard...please read them better and report...my layout is verified and the pots are wired the right way just like you see in it...
@zambo
Hmm, I tried all day today to get a tube circuit to work and I think it is my wall wart that causes so much of this buzzing. ??? I saw that one guy made a bridge rectifier to clean up the AC noise. I think that my next project will be to make a circuit to clean up this nasty signal. I thought that maybe a 7812 chip would do this but I still get lots of noise. The voltage is regulated, but the buzzing is horrible. I plugged in a 9V battery and it was super quiet. Anyways, this is where I am at now. I'm getting good readings on my pins and I even was running the plates at +15V. So, I'm going to order some parts to make a rectifier/regulator, do some research, and maybe try to put a fuzz circuit in an enclosure. This valvecaster is actually only my second circuit and I haven't put my first circuit in an enclosure yet. Well, I'm off to search the forums for some info on rectifiers. If you know of a way to make a rectifier circuit with 1N4001 rectifiers, I could certainly put it to good use.
@Renegadrian
Yes, I think you are right. I think I may be doing something wrong. As I said to zambo, my wall wart is really making a lot of noise. Also, I might order some veroboard while I am ordering parts for a rectifier. I don't know why the tube projects are giving me such a hard time. I built a 2 transistor fuzz circuit and it works great. Do the tube circuits suffer more than other circuits from bad wall warts?
Bill
Edit: I couldn't stand it, so I started over and made the standard 3 knob valvecaster. It works!, but still lots of humming. I am going to make a quick huminator (the beavis project). I am 99% sure that this one is correct. However, is it common to hear popping or clipping when Volume and Gain is up to 100%?
I've got a question about using the voltage multiplier. Do you need to use a regulated supply or does the multiplier circuit clean things up for you?
Quote from: tipetu on January 09, 2011, 04:12:17 PM
I made a little rectifier circuit (for the original pedal of this thread) and it is now 1000000% quiet!! No 50-100Hz hum whatsoever!!
The reason why I`m posting this now is because I KNOW there are people out there who built this pedal and are struggling with bad wall warts.
Connect this simple (yet damn effective) circuit between the crappy wall wart and the pedal, and all the demons will dissapear.
(http://img94.imageshack.us/img94/4394/img1072yo.jpg)
Notice the voltageregulator is a 12V regulator. Heck I even used it on 9V and they both sounded wonderful!
(http://img96.imageshack.us/img96/7814/superrectifier.jpg)
And here is a videoclip with studio recording.
http://www.youtube.com/watch?v=ZDNPehH2VZQ
Just wanted to share that with yall.
tipetu,
How much noise were you getting from the bad wall wart? My noise is so bad that I when I turn Volume and Gain up to ~100%, I hear popping and clicking. The popping is at regular intervals, and if I change the .01uF capacitor, the clipping will get faster or slower. I am going to attempt to make something like you made but I don't have a 2200uF cap. Do you think the 2200uF is very important here?
Thanks,
Bill
hello again,
sorry for posting so many times. I am having some issues with humming and buzzing with my valvecaster. I even get a large amount of buzzing when I use a 9V battery. I really like the sound of it, but I am scared that if put it in an enclosure that it will still be buzzing really bad. When I press the bypass switch, it is a crystal clear clean signal. But the second I turn on the valvecaster, it starts buzzing again. I even tried a 1000uF and 2200uF capacitor as well a full-wave bridge rectifier from radioshack and it helped some, but not very much. I read other posts where these filters and regulators have worked perfectly, so I am just trying to fix this problem. Thanks for your patience. I am fairly new at this, but I did make a fuzz pedal on my breadboard as well, and it didn't buzz like this one does. Any ideas?
Thanks a lot,
Bill
@ Bill,ok check it out. I use 1spot walwarts and they work every time. A lot of times buzzing is a bad ground. sometimes wires that are to long will pick up buzz as well. A bread board is a great experimentors tool but they are prone to buzz as the circuite is not enclosed in a grounded, sheilded enclosure. Go get a 1spot 9volt walwart and see if it still buzzez. Make sure whatever walwart your currently using is rated for 200 milli amps or more.
Quote from: BarnyardBill on January 18, 2011, 08:22:12 PM
@zambo
Hmm, I tried all day today to get a tube circuit to work and I think it is my wall wart that causes so much of this buzzing. ??? I saw that one guy made a bridge rectifier to clean up the AC noise. I think that my next project will be to make a circuit to clean up this nasty signal. I thought that maybe a 7812 chip would do this but I still get lots of noise. The voltage is regulated, but the buzzing is horrible. I plugged in a 9V battery and it was super quiet. Anyways, this is where I am at now. I'm getting good readings on my pins and I even was running the plates at +15V. So, I'm going to order some parts to make a rectifier/regulator, do some research, and maybe try to put a fuzz circuit in an enclosure. This valvecaster is actually only my second circuit and I haven't put my first circuit in an enclosure yet. Well, I'm off to search the forums for some info on rectifiers. If you know of a way to make a rectifier circuit with 1N4001 rectifiers, I could certainly put it to good use.
@Renegadrian
Yes, I think you are right. I think I may be doing something wrong. As I said to zambo, my wall wart is really making a lot of noise. Also, I might order some veroboard while I am ordering parts for a rectifier. I don't know why the tube projects are giving me such a hard time. I built a 2 transistor fuzz circuit and it works great. Do the tube circuits suffer more than other circuits from bad wall warts?
Bill
Edit: I couldn't stand it, so I started over and made the standard 3 knob valvecaster. It works!, but still lots of humming. I am going to make a quick huminator (the beavis project). I am 99% sure that this one is correct. However, is it common to hear popping or clipping when Volume and Gain is up to 100%?
Also when volume and gain are 100% up you are probably boosting your amps input beyond the point of sounding good at all. there is a point where to much boost is a bad thing and sounds awful. How does it sound with the gain at 75% and the volume at 65% or even half. Just a little boost is the magic touch sometimes. Fwiw ;)
Quote from: bassmannate on January 18, 2011, 08:27:13 PM
I've got a question about using the voltage multiplier. Do you need to use a regulated supply or does the multiplier circuit clean things up for you?
I have only used a regulated supply so i dont really know the anwer..sorry. I hate to sound like the 1spot 9v adaptor salesman but i really have had excellent luck with these so i stick with them. the multiplier i copied from frequencycentral worked good and was really quiet though.
Quote from: zambo on January 19, 2011, 09:10:05 PM
Quote from: bassmannate on January 18, 2011, 08:27:13 PM
I've got a question about using the voltage multiplier. Do you need to use a regulated supply or does the multiplier circuit clean things up for you?
I have only used a regulated supply so i dont really know the anwer..sorry. I hate to sound like the 1spot 9v adaptor salesman but i really have had excellent luck with these so i stick with them. the multiplier i copied from frequencycentral worked good and was really quiet though.
Yeah, I've got a 12v 1spot. I'm just thinking of feeding the multiplier a higher voltage like from a 19.5v laptop power supply to get higher voltages.
all the ones i have seen will only take up to 16 regulated i think. After that they do bad things. I think .
Quote from: zambo on January 19, 2011, 09:34:03 PM
all the ones i have seen will only take up to 16 regulated i think. After that they do bad things. I think .
Ok, so I may want to just stick with 12v into the multiplier.
Ok, I've got a good report for once :D Here is how it happened. I took the valvecaster off of my breadboard and decided to try out the fuzz/booster circuit from a b.y.o.c. thread. I got it working with no buzzing. Then, I saw that I had some more room on the breadboard, so I said "heck, I might as well build the 'valvecaster' again if it'll fit. So, the valvecaster continues to hum so loud that I could barely hear the guitar. Then I ran the fuzz/booster into the valvecaster and after playing with the pots for a minute, the hum was gone and the tube sounded better than ever! Both circuits running off of the same power supply with a 7812 regulator. And, the heaters are getting 15V straight from the power supply. It sounds GREAT. Thanks for being patient with me and for all these great ideas.
-Bill
Quote from: BarnyardBill on January 19, 2011, 01:32:39 PM
Quote from: tipetu on January 09, 2011, 04:12:17 PM
I made a little rectifier circuit (for the original pedal of this thread) and it is now 1000000% quiet!! No 50-100Hz hum whatsoever!!
The reason why I`m posting this now is because I KNOW there are people out there who built this pedal and are struggling with bad wall warts.
Connect this simple (yet damn effective) circuit between the crappy wall wart and the pedal, and all the demons will dissapear.
(http://img94.imageshack.us/img94/4394/img1072yo.jpg)
Notice the voltageregulator is a 12V regulator. Heck I even used it on 9V and they both sounded wonderful!
(http://img96.imageshack.us/img96/7814/superrectifier.jpg)
And here is a videoclip with studio recording.
http://www.youtube.com/watch?v=ZDNPehH2VZQ
Just wanted to share that with yall.
tipetu,
How much noise were you getting from the bad wall wart? My noise is so bad that I when I turn Volume and Gain up to ~100%, I hear popping and clicking. The popping is at regular intervals, and if I change the .01uF capacitor, the clipping will get faster or slower. I am going to attempt to make something like you made but I don't have a 2200uF cap. Do you think the 2200uF is very important here?
Thanks,
Bill
Hi, yeah, I had EXACTLY the same problems you describe! Popping and buzzing and annoying sound. I would strongly recommend you building a rectifier circuit like this! The 2200µF is not so important, as long as you have a somewhat similar polarized cap. Go for it!
tipetu,
Ok, thanks a lot. I have since discovered that a fuzz circuit I have been messing with seems to clean up the valvecaster's humming as well. It is a fairly straightforward booster circuit with 2 Si transistors. I am new to circuits and DIY so I haven't yet figured out how it accomplishes this. I run my cables through the fuzz circuit first and then through the valvecaster. Next I want to try the other boost in front it that Renegadrian suggested. His layouts have helped me a lot.
About the full wave bridge rectifier. I picked up one of these from radio shack. It kinda looks like an oversized 7812 regulator except with 4 pins. Will this work in place of the 4 RL205 diodes?
Bill
Quote from: BarnyardBill on January 20, 2011, 09:43:57 AM
tipetu,
Ok, thanks a lot. I have since discovered that a fuzz circuit I have been messing with seems to clean up the valvecaster's humming as well. It is a fairly straightforward booster circuit with 2 Si transistors. I am new to circuits and DIY so I haven't yet figured out how it accomplishes this. I run my cables through the fuzz circuit first and then through the valvecaster. Next I want to try the other boost in front it that Renegadrian suggested. His layouts have helped me a lot.
About the full wave bridge rectifier. I picked up one of these from radio shack. It kinda looks like an oversized 7812 regulator except with 4 pins. Will this work in place of the 4 RL205 diodes?
Bill
Hi,
the 4 rl205 diodes are there only to convert power from AC to DC.
7812 component is used to lower a voltage input to 12v. For instance, if you put 18v in entry of this component, you'll have around 12v.
Fabien.
I made a short vid of me playing through my breadboarded fuzz/valvecaster today. You can see the hot tube. http://www.youtube.com/watch?v=rgSLIworWSQ I will post the finished product soon (hopefully).
:)
@fabien
But is he using the 4 diodes to possibly clean up an residual AC that gets through?
http://www.radioshack.com/product/index.jsp?productId=2062580 <----This is the bridge rectifier I was asking about if it is equivalent to the 4 diodes.
-Bill
Yes I`m using the 4 diodes to convert the AC signal to DC. You may also use the little 4 pin chip you discovered. It has the exact same function but looks a little different. Be sure to check out the data sheet for correct pin layout.
Hey guys!
I must say that matsumin's schematics is somehow becoming mysterious for me...I've built it 3 times and it didn't work 3 times...
I verified my perfboard so many times that I can't even remember how many...(remember rainman)
At best, i get a very low volume nasty sound with a huge hum, and at worst, I get nothing...
What is hurtful is that I'm not even a noob in building pedals...what the ****!
Does anyone have a perfboard layout that works?!
Thanks!
Quote from: BarnyardBill on January 20, 2011, 01:29:12 AM
And, the heaters are getting 15V straight from the power supply.
-Bill
powering the heater beyond the voltage tolerance will shorten the tube life significantly. 12.6V plus 10% is 13.8V which is the highest tolerance. If you lower it to 10 - 12 volts it will still sound great and last longer
Quote from: artsinbloodshed on January 20, 2011, 03:44:49 PM
At best, i get a very low volume nasty sound with a huge hum, and at worst, I get nothing...
What is hurtful is that I'm not even a noob in building pedals...what the ****!
Does anyone have a perfboard layout that works?!
Thanks!
@artinbloodshed
I think I can relate to your problem and actually I am glad you are having this problem because it means that we are both doing it correctly and getting bad results. I also did this circuit numerous times and just yesterday I managed to get it to work nicely.
Here is what I did(by happenstance) to get it working. I put a very loud fuzz pedal circuit(http://buildyourownclone.com/board/viewtopic.php?f=9&t=11899&st=0&sk=t&sd=a) on the same breadboard that the valvecaster is on and when I run them both(linked together with cables) from the same wall wart they work great. I can even switch the order of them and it still works. I tried powering the fuzz circuit and the valvecaster separately and started the loud humming again. So, as of now, it is working as long as both circuits are getting power from the same source. Maybe a daisy chain would work also, but I don't have one to try it. Also, both circuits have a 3PDT switch and they both will work independently or together. I have also heard reports of other booster circuits sounding really good with the valvecaster.
I still don't know why this makes it work, but it does. If you try this, please let me know if it works for you too. I am glad I was able to get mine working, but I still feel like something is different about mine. ??? :icon_question:
http://www.youtube.com/watch?v=rgSLIworWSQ
Hope this helps,
Bill
@PaulBass
Oops, I meant to say that pin 5(heater) is getting ~12V and 15V is running to resistors that go to pin 1 and pin 6. This is correct right? I don't want to fry my baby. :)
-Bill
Quote from: artsinbloodshed on January 20, 2011, 03:44:49 PM
Hey guys!
I must say that matsumin's schematics is somehow becoming mysterious for me...I've built it 3 times and it didn't work 3 times...
I verified my perfboard so many times that I can't even remember how many...(remember rainman)
At best, i get a very low volume nasty sound with a huge hum, and at worst, I get nothing...
What is hurtful is that I'm not even a noob in building pedals...what the ****!
Does anyone have a perfboard layout that works?!
Thanks!
do you have only one tube? It's better to have several for troubleshooting. Also I always test the circuit with a 9 volt battery before hooking up to a power supply. If none of tubes work with a 9 volt battery that means there is either an error in the circuit, bad solder joint, or bad component
@ artsinbloodshed - are you using a 12au7? some people use a different tube like an ax7 or at etc. those dont always work at low voltage. au7 will work. makes sure you have all your capacitor polaritys correct. also the resistor from pin 3 to ground and pin 7 to ground ( i think they go to pin 4 on the beavis layout) can be troublesome and cause no sound. My first one didnt work the first time either.Look for grounding issues. The walwart is a huge help or hinderance. They can cause motorboating, hum etc. Try the battery first. if that works a simple 200ma or more 9 volt walwart from boss or 1spot should work. good luck!
Hi everyone,
i'm working on making a power supply on a pcb, for everyone who encounters problems, and that could be used in fact for other uses.
This would include at first a rectifier (to avoid problems of inversion of polarity), a capacitor, followed by a 7812, followed by another capacitor.
It would also include all the necessary pads to connect directly wires for the voltages.
Two pads for heaters, two pads for 12v, and two other pads for powering up a led for example (including a resistor).
This should make things a little easier to wire.
This should more or less something like that :
(http://fabienl.free.fr/powersupply.JPG)
Fabien.
Fabien,
Did this power supply you made clean up all the noise you were getting?
Bill
This power supply is not done yet. As for now, i'm trying to make a fine pcb, and as it will be my very first one done in a cad software, i work slowly !
What i had tested firstly, without pcb was :
a wall wart DC 12v (giving 16v in output).
followed by a 7812 regulator, followed directly by a 100uf capacitor. The result was a fine 12v in output.
But as i haven't get yet the valvecaster to work successfully (disto doesn't work), the only thing i can say is that it purifies the power supply, and therefore all thoses annoying noises.
Finally, I want to do this pcb to allow delivering a filtered 12v, and simplify a little all the wiring.
Fabien.
Quote from: zambo on January 18, 2011, 07:15:30 PM
i believe on those caps you have to look at the numbers as a code. The code will tell you what size they are. As far as hissing, Mine are pretty quiet. I use a .002 on the coupling caps a lot of times when running multiple valves in series. For a plain valvecaster I run .01 and .0047 for input and coupling caps. I never turn it all the way up as they sound bad to me that way. Volume at 3/4 and gain about the same is my fav. Picofard sized caps i think are to small for any good sound. Bigger caps like stock value sound awesome on single coils. thats my opinion what its worth :P
hello again zambo,
I wanted to make a few confirmations about the cap sizes you use for a single valvecaster. You use .01uF in place of the 1uF coupling cap, .0047uF in place of the .047uF coupling cap and you use .0047uF in place of the .047uF input cap?
Thanks,
Bill
Quote from: Renegadrian on January 18, 2011, 08:12:55 PM
Bill, those values are way out of standard...please read them better and report...my layout is verified and the pots are wired the right way just like you see in it...
you were correct about those values. However, I am getting a lot better results when I combine the vavlecaster with a another booster type circuit. I have heard other builders having the same issue with loud buzzing and little to no guitar signal. Did you experience this when you built your many variations?
Thanks for all the layouts Renegadrian,
Bill
Quote from: BarnyardBill on January 24, 2011, 12:46:26 PM
Quote from: zambo on January 18, 2011, 07:15:30 PM
i believe on those caps you have to look at the numbers as a code. The code will tell you what size they are. As far as hissing, Mine are pretty quiet. I use a .002 on the coupling caps a lot of times when running multiple valves in series. For a plain valvecaster I run .01 and .0047 for input and coupling caps. I never turn it all the way up as they sound bad to me that way. Volume at 3/4 and gain about the same is my fav. Picofard sized caps i think are to small for any good sound. Bigger caps like stock value sound awesome on single coils. thats my opinion what its worth :P
hello again zambo,
I wanted to make a few confirmations about the cap sizes you use for a single valvecaster. You use .01uF in place of the 1uF coupling cap, .0047uF in place of the .047uF coupling cap and you use .0047uF in place of the .047uF input cap?
Thanks,
Bill
Almost. Leave the 1uf cap the same. Replace the input with .0047uf ( i make this one switchable using a dpdt mini toggle switch to .022uf or .047uf a lot of times on a single valvecaster). Replace the cap from pin 1 to pin 7 with .01uf or .022uf. This should drive the input of a decent guitar amp hard enough to make some seriouse grind. If you just want to warm up another distortion use the bigger caps.
Quote from: BarnyardBill on January 24, 2011, 01:04:33 PM
I have heard other builders having the same issue with loud buzzing and little to no guitar signal. Did you experience this when you built your many variations?
Never, even my first valvy (which actually was my third pedal built ever) sounded good at first try. There can be differences
related to the tube you use (all tubes have their own character) but the signal is always loud!
Quote
Thanks for all the layouts Renegadrian,
Bill
My pleasure, I am glad if anyone finds them useful!!! :icon_cool:
Hello good people ,great work!and very friendly atmosphere!first time building the valvecaster with 12Vdc , second time building a pedal circuit,please help because i'm confused.I have only mono jacks and i've noticed that in some layouts there is a stereo and a mono jack,do i have to go and buy a stereo jack neccesarily ? And another thing is that i bought a six contact switch S1,that's because i saw it in a by-pass diagram method from the internet, but i see that a 9 contact switch is being used in the layout.Am i going nowhere like that? :-\
@voo86 :no you'll be ok, stereo jacks are usually used to just switch the 9v battery on/off when plugging in..(saves juice when unplugged etc)..in your case your using 12v...so it wont matter...
unless you put a car battery in it ... :icon_mrgreen: :icon_wink:
as for the switch..
the 9 pole '3pdt''s are used just to have the option of an on/off led .....your 6 pole 'dpdt' will be ok, but no led ok..
welcome... :icon_wink:
thank you dead astronaut,do you play in god is an astronaut??? you were very helpful!!!i don't mind putting a led indicator at this stage,i just want it work decent.Yet, you said that i need 3dpdt for a led indicator addon.So , is this correct?
(http://i1189.photobucket.com/albums/z422/kenostadontia/dpdt2.gif)
great you tube channel and track by the way,i m subscribing,cheers
yep, that is a version of a millenium bypass...with led...and yes can be done..with dpdt...(your switch)
i never bother with that type of bypass i just buy a 3pdt and wire it up like..
http://img.photobucket.com/albums/v75/kev93_10/3pdt-wiring_png.png?t=1244105908
and no i dont play in 'god is an astronaut'... :icon_wink:
glad you like the channel...cheers... ;D
ok thanks mate :icon_biggrin:
It looks like the trick with the Valvecaster is keeping the heaters at 12V while having a higher voltage going to the anodes. since there is a 100K resistor connecting pins 5 & 6 there is always voltage leaking from pin 6 to 5. I have it running at 12V but I know it will sound a lot better running at around 30V. I have a dual power supply that puts out 32V and 16V. Is there a way to have 32V going to the anodes and breaking down 16V to 12V for the heaters? I'm thinking using a voltage regulator to convert 16V to 12V but how I do run 32V to the anodes without it leaking to the heaters?
That's what i 've been wondering today.Maybe you can use the dual power supply just for the circuit, and a separate supply of 12,6Vdc for the filament.Well, someone more experienced can inform us.
Quote from: yoo86 on January 27, 2011, 11:16:29 AM
That's what i 've been wondering today.Maybe you can use the dual power supply just for the circuit, and a separate supply of 12,6Vdc for the filament.Well, someone more experienced can inform us.
the problem is the 100K resistor that connects pin 5 to 6. whatever voltage is going to pin 6 it will also go into pin 5. if the resistor isn't connected to pin 5 the tube won't work. I'm gonna try using the 32V part of the power supply and using an LM317 to lower the voltage to the heater
pin 5 and 6 are connected through the circuit.So, if pin 5 is supplied seperately there is no intervention at all.If you already gave it a try please let me know your results
Quote from: yoo86 on January 27, 2011, 03:25:51 PM
pin 5 and 6 are connected through the circuit.So, if pin 5 is supplied seperately there is no intervention at all.If you already gave it a try please let me know your results
I was gonna try this design except I'll wire an LM317 before the 12.6VDC input to adjust the 16V down to 12.6. I can wire the 32V from psu to the 24VDC. looks like the designer changed R2 & R3 but I'm gonna keep those values as same as Matsumi design (220K & 100K) so there is no gain loss
(http://sites.google.com/site/macturkey101/ValvedSchem.gif)
ah ok.please tell me,what clarity stands for? and C5 by the cathode? ???
hello!
i'm having a problem (or two) with my homemade valvecaster and i thought you could help me
firstly...it sounds strange...with gain at max its like some crunch but its not smooth ,its like a "cracking" sound-the tube is an ecc82 RFT (equivalent to 12au7);this sound is more "visible" on the thick strings E,A,and D
secondly...when the tone pot is at the minimum i get a bit of hiss,the hiss dissapeares when i turn the pot at max but i also loose the treble,so i have to find a solution to this problem
smaller value plate resistors give a cleaner boost. The resistor from pin 5 to pin 1 and the other to pin 6 can be disconected from pin 5 altogether. So just the 12.6 to pin 5. the higher voltage will go to the resistors connected to pin 1 and pin 6. That will seperate your heater from your plate voltage.
The gain at max setting never sounds good to me on this design. 3/4 seems to be the real max gain thats usable. The hiss is probably due to the fact that the gain is maxed or you could be overdriving the input to much.
on a regular tube amp in the preamp a bypass cap on the cathode resistor ( C5) helps boost some of the highs by amplifying them more. Some times it works on low voltage designs, sometimes it causes problems. Not sure in this case. Hope this helps.
Oh yeah, when all else fails, suspect your power supply.
Quote from: dano12 on December 13, 2007, 09:31:09 AM
Regarding the 386 amp, that's the route I'm taking with my wired tube socket thing. Trying to fit it in a small plastic case.
For the questions about using a tube other than the 12AU7, as said earlier, they are higher gain and won't work nicely unless you modify the circuit, I don't know how to do that part.
tubesandmore.com has the tube and sockets, it is the standard 9-pin tube socket you would use for guitar amp preamp sections.
Here is a rough *unverified* wiring diagram for anyone who wants to try it.
(http://www.beavisaudio.com/Projects/ValveCaster/MatsuminValveCasterWiring.gif)
Would it be possible, on this schematic, to use a DPDT to switch between two separate gain pots and to switch on and off an LED indicator light? I'm VERY noob at this so I could be wildly off with this but the way I guess it would work is that the two different gains would be running off to ground and the LED would be coming from the 9V then run off to ground too. Would the LED coming straight from 9V (via a resistor of some sort) and running to ground cause problems? Has anyone any idea what kind of current this circuit draws? Would it make any sense at all to run the LED back to pin 5? All advice greatly appreciated! It'd be great to be able to have a pedal with a clean tubey pre channel and a higher gain tubey overdrive channel all in one box.
Hello everyone, I just want to start off by saying that this project has been consuming my life for the past few weeks, I love it! You all seem so helpful and contributive.
Back to business though, I seem to be having a similar problem as Red_92. I can't seem to get as much gain as i hear in sound clips and youtube videos of the valvecaster (are they just cranking the volume on the pedal so to drive the amp's input to get distortion?). The little crunch that I do get however, sounds very buzzy like a bee. Very flat with no bite. I followed the point to point beavisaudio schematic using original resistor and capacitor values with a removed tone control. I have different R2 and R3 resistors and tried a variety of 12AU7 and 12AX7 tubes with a bit of a difference in gain, but still that flat buzzing sound. It is powered with a regulated 12V with a switchable 9V battery going to the plates for a bit more volume and gain but still not the sound I hear other people getting.
My voltages are:
P1 8.21V
P2 -0.44V
P3 0V
P4 0V
P5 11.9V
P6 8.68V
P7 -0.47V
P8 0V
P9 has fallen out of the socket - its not need anyway right?
If you guys have any ideas on how to get that full, rich, crunchy tube tone, that would be awesome :) thanks in advance
if you are fairly confident that you have wired it correctly and that it is working, then I think the next step would be to try a higher voltage. For me, I like the way it sounds, but I am going to build a voltage pump before I put it into an enclosure. Also, if you have any good booster pedals, try putting that in front of it. Other than that, I would look at changing the respective caps and resistor sizes. Did you try that yet?
Bill
Quote from: zambo on January 27, 2011, 06:31:15 PM
The resistor from pin 5 to pin 1 and the other to pin 6 can be disconected from pin 5 altogether. So just the 12.6 to pin 5. the higher voltage will go to the resistors connected to pin 1 and pin 6. That will seperate your heater from your plate voltage.
Oh yeah, when all else fails, suspect your power supply.
supplying the power is trickier than I thought. I disconnected the 100K resistor to pin 5 and ran 12.6V to the heater using an LM317 and 32V going to the anodes. all I got was a constant beep tone "boooooooop". The power supply is rated at 700mA ??? I reconnected the 100K resistor to pin 5 and ran 12V from another psu to the heater and anodes and it worked. I don't think it's the power supply because it works with other devices. I'm stumped ???
Quote from: BarnyardBill on January 29, 2011, 11:22:44 AM
if you are fairly confident that you have wired it correctly and that it is working, then I think the next step would be to try a higher voltage. For me, I like the way it sounds, but I am going to build a voltage pump before I put it into an enclosure. Also, if you have any good booster pedals, try putting that in front of it. Other than that, I would look at changing the respective caps and resistor sizes. Did you try that yet?
Bill
i have tried doing what others have done - using an 18V or 24V ac adapter into a 7812 regulator and sending the higher voltage to the plates, however I ended up frying the regulator from overheating, even with a heatsink :S I did try your suggestion of putting a pedal in front which gave a more satisfying gain that i liked, but it still has that buzzy sound on the E, A, and D strings. I added a switchable input cap with a 22nf and 47nf and tried a few different caps for C2 which changes the bass response a bit, and i've tried a few different resistors except for R4 as im not too sure what it does. All of which don't really change the actual character of the gain too much. I could however live with the sound of the booster in front, but my plan is to sell these to my friends who don't all have booster pedals of their own, so that makes me wonder if its possible to add a pot that increases the input signal?
for troubleshooting I dumped the LM317, disconnected the 100K to pin 5 again, tried a 15V wallwart to the anodes and kept the other 12V wallwart on the heaters. made sure all the grounds were connected together, including the wallwart grounds. the tube lit up but no signal :-\ I don't understand why I only get a signal when the 100K resistor is connected to pin 5. another strange thing is when the tube in not inserted it reads:
pin 1 - 15V
pin 5 - 12V
pin 6 - 15V
when the tube is inserted it reads:
pin 1 - 14V
pin 5 - 11.89V
pin 6 - 5V ???
When I used the 32V supply on the anodes it reads (tube not inserted):
pin 1 - 32V
pin 5 - 12V
pin 6 - 32V
it reads (tube inserted):
pin 1 - 31V
pin 5 - 11.89
pin 6 - 10V ???
so the problem is obviously on pin 6 ???
Hello again everybody, built it just now with 12Vdc,2 mono jack (I/O) and 6 contact switch.Volume works , tone variation is hardly noticed, but what bugs me is that gain is not working... As a pot it seems to be working..also connections are checked ...Any ideas????
Here are my measurements Pin 1 9,75 V
2 -0,14
3 0
4 0
5 12,6
6 10,38
7 -0,36
8 0,12
9 6,28
ok it seems i put a 4K7 pot instead of a 47K...i just changed it..So now gain seems to work as a volume pot.So if volume is max, gain takes it to eleven(spinal tap) no overdrive whatsoever,please help
my valvecaster is still on my breadboard and I was fiddling with it yesterday after I soldered a nice 3-out daisy chain. I tried using the daisy chain on the valvecaster and it began to buzz again. So, after trying a few other wall warts, I concluded that the only one doesn't cause a bad buzzing noise is the 15V Toshiba Laptop Charger. At least I assume it's for a laptop. I have a 12V regulator to make sure the heaters dont get any more than 12V. I just though this might help if anyone is still troubleshooting their valvecaster for loud buzzing or humming.
Next I want to try a higher voltage on the plates. I am just deciding on some other things before I make an order.
-BIll
oops :P found out I made one of the ground connections come loose while I was wrestling with this thing :P I finally got it to work. Wow it really sounds great! It has a full warm earthy sound :icon_cool: I use a 12AU7WA tube in it. I noticed the gain pot is scratchy due to DC current going through it. gonna try different cap values before the gain pot to see what sounds best while blocking the DC
Could any of you possibly make a quick recording of the valvcaster with the Volume unity gain (no boost or cut) and gain knob at full? Just so I could compare and further troubleshoot my pedal? thanks so much :)
Quote from: Anon on January 31, 2011, 05:04:45 PM
oops :P found out I made one of the ground connections come loose while I was wrestling with this thing :P I finally got it to work. Wow it really sounds great! It has a full warm earthy sound :icon_cool: I use a 12AU7WA tube in it. I noticed the gain pot is scratchy due to DC current going through it. gonna try different cap values before the gain pot to see what sounds best while blocking the DC
hmmm tried different caps both film and electrolytic and between pin 3 and the gain pot and all it did was attenuate the signal to almost nothing. I wonder if there is a way to block the DC to the gain pot without killing the signal. also the 2n2 cap going from pin 3 to ground really brightened up the sound nicely
Hello ..I am a bit confused..I looked again my measurements.I can't get pin 1 below 8.32V.Running it at 12.6 .All other pins are as the ones stated correct.
R1 is 890K , R2 270K and R3 47K .You can notice the gain now a bit (little bit).I tried changing R2 values..Trim pot @ 1M gave pin 1 7,36V...Went up to 2,2M and as a result i had 5,46V at pin one but no gain.I ended up putting a 270K , close to the schematic reference.Connections quadchecked , so are all components.Can please someone give the noob an explanation?Sorry for bad usage of english language.
Quote from: eric1123 on January 31, 2011, 11:54:49 PM
Could any of you possibly make a quick recording of the valvcaster with the Volume unity gain (no boost or cut) and gain knob at full? Just so I could compare and further troubleshoot my pedal? thanks so much :)
http://www.youtube.com/watch?v=rgSLIworWSQ
this is just me messing around. I cant remember how high the gain was, but probably about halfway. Also, a fuzz pedal is in there too.
Also,
check out this: http://www.youtube.com/watch?v=HveUY7eivfI&feature=related
i dont know why people stick to the 12au7. im runin mine with a very used 12ax7 and it still will be a clean boost but it will get sum drive into it that sounds like a cranked princeton . i also found if u use used up tubes that have ran hours on an amp that it runs better than a new tube. its just seems more broke in and is more effficient to be ran on 9 or 12v. i used all orange drops on mine and built to be pretty much what u would find on a turret board old preamp section instead of treating it like a transistor stylized circuit. it loves being the last in the signal chain. love it . all hail matsumin!
Quote from: ultran8 on February 01, 2011, 04:32:43 PM
i dont know why people stick to the 12au7. im runin mine with a very used 12ax7 and it still will be a clean boost but it will get sum drive into it that sounds like a cranked princeton . i also found if u use used up tubes that have ran hours on an amp that it runs better than a new tube. its just seems more broke in and is more effficient to be ran on 9 or 12v. i used all orange drops on mine and built to be pretty much what u would find on a turret board old preamp section instead of treating it like a transistor stylized circuit. it loves being the last in the signal chain. love it . all hail matsumin!
some people built twincasters with a 12AX7 as the second tube that can be switched in/out of the circuit. thats what I plan on building next
Quote from: zambo on January 27, 2011, 06:31:15 PM
smaller value plate resistors give a cleaner boost. The resistor from pin 5 to pin 1 and the other to pin 6 can be disconected from pin 5 altogether. So just the 12.6 to pin 5. the higher voltage will go to the resistors connected to pin 1 and pin 6. That will seperate your heater from your plate voltage.
Thanks for the tip on getting a cleaner boost! I am going to try this. I'm still procrastinating on making the voltage pump.
Also, does anyone know of a schematic for an efficient voltage pump that goes up to around +200V?
-Bill
Bill, it's the nixie supply!
(http://sites.google.com/site/macturkey101/ValvedSchem.gif)
added a rotary switch at C5 to select different cap values and it sounds great! with each cap selection you get a bump at that frequency so you get different tones. some people complain the valvecaster is too dark sounding but adding a cap there will make a huge difference. at 2n2 I get a bright glassy sound, at 22n I get a bassy hi-mid sound
108 pages and still tweaking, experimenting, and finding good or bad results...
12ax7 - it doesn't seem to work at 12v not with the valvy circuit not with others I've tried - gotta raise the voltage a little, not 300V but not less than 40.
tried another voltage multiplier, I made a vero layout (http://www.aronnelson.com/gallery/main.php/v/Renegadrian/40106+voltage+multiplier.gif.html) - it works good with the valvy, and a chinese 12ax7 seems to benefit and gives all its best. I used a battery with 7.2V, out is 46.3V
gotta try to add a cap between pin 3 and ground! Nice if it brightens things a little!!! thx Anon!
Hey all. I've built a couple of these using the basic original design and running all point to point. Is there a verified layout on vero board for the original circuit, minus the tone knob? I have glanced through the entire thread, but I can't seem to find what I'm looking for.
Thanks,
Dan
You really did?! I don't think so, Dan... :icon_evil: Allright, I'll point you where you can find it...Just go to the layout gallery in my personal folder.
Thanks for the layout Renagadrian. I do appologize for not finding it myself.
Since I am not a regular poster here, I can see why you doubt my honesty when I said I searched this whole thread. But believe me, I am not the kind of person who wants to bug others for answers I could find myself. I do appreciate all you've personally done to help keep this thread (and circuit) alive.
Dan
that's ok man, you didn't have to excuse...you're welcome! :icon_wink:
My first sentence has to be read in a funny way, right!? :icon_smile:
Have fun with tubes!!!
Quote from: Renegadrian on February 02, 2011, 12:21:29 PM
Bill, it's the nixie supply!
Renegadrian,
I did some reading about the nixie supply. You have a nice SMPS on your layouts, but the output says HV. I understand that it means high voltage, but do you know how much it is exactly? I am just wondering.
One more question. :) Do you think that a nixie supply is better than a voltage pump for this? I noticed that they seem to work in different ways.
Thanks again,
-Bill
hey quick "i'm a dipsh*t" question. on my tube socket there is a center pin on the back? what is this for, and can i put a 3mm led in it to illuminate the tube?
...is it a ground?
Quote from: BarnyardBill on February 07, 2011, 02:43:47 PM
Quote from: Renegadrian on February 02, 2011, 12:21:29 PM
Bill, it's the nixie supply!
Renegadrian,
I did some reading about the nixie supply. You have a nice SMPS on your layouts, but the output says HV. I understand that it means high voltage, but do you know how much it is exactly? I am just wondering.
One more question. :) Do you think that a nixie supply is better than a voltage pump for this? I noticed that they seem to work in different ways.
Thanks again,
-Bill
THX, actually it can be credited to Rick as it follows its perf layout almost verbatim.
Voltages go from +-90V to +200V - basically you want to have a good voltage (say 200 or even less) while not running it at full throttle (it began to smell a little bad after a while so I turned the trimpot down a little, a bunch of V less but it won't blow that way!)
I think that circuit is quite good! It brings out a good amount of voltage, and verified to work good with tubes, as it's intended to be from the start. other ckts are good too, maybe less V but maybe smaller.
I made that 40106 multiplier, +-78v with 12v input. Sure it's less, but it's also smaller.
So it's up to you and your experimenting! I'd say try one of the others with one-tube-preamp/pedals while favour the nixie if it has to be inside a small amp like Ricks'
my 2c fwiw
So I have just completed my third valvy (this one, I incorporated a swtichable LPB1 in the circuit). Everything was working great, then I turned on my delay pedal and it all went to hell (yes, I've switched the delay back off). The valvy first went near silent, and now it appears to be a valve powered sine wave generator (with gain controlling the pitch and tone controlling the shape, volume is still volume). Now, as cool as it is to have a switchable synth on my pedal board :icon_wink:, I'd really like to know what the hell could've gone wrong. I've pulled everything back out and it all looks solid. Also, the LPB-1 side still acts as it should. I switch it on and get a nice boost. I kick on the Valvy side and it's pure sine wave. Any thoughts?
Recoded a song today with the valvie! Love the sound at the end!
http://www.youtube.com/watch?v=bQnpBpVI74U
Quote from: pazuzu on February 07, 2011, 03:12:52 PM
. on my tube socket there is a center pin on the back? what is this for, and can i put a 3mm led in it to illuminate the tube?
You can use it for mounting components directly to the socket, but otherwise it's nothing special. Yes, you can stuff an LED in there.
Quote from: tipetu on February 10, 2011, 10:09:53 AM
Recoded a song today with the valvie! Love the sound at the end!
http://www.youtube.com/watch?v=bQnpBpVI74U
very nice!!! :icon_wink:
How hot does that tube get? I would like to be able to fit it inside the enclosure for portability but if heat is going to be an issue that might not be feasible. Has anyone else mounted it inside?
Quote from: Edalicious on February 14, 2011, 05:56:35 AM
How hot does that tube get? I would like to be able to fit it inside the enclosure for portability but if heat is going to be an issue that might not be feasible. Has anyone else mounted it inside?
It barely gets warm to the touch. Mounting it in a box won't be a problem.
Quote from: merlinb on February 14, 2011, 03:50:01 PM
It barely gets warm to the touch. Mounting it in a box won't be a problem.
Excellent! I might try to cut a hole in the enclosure anyway. It seems a bit of a waste to stick a tube in a pedal and not show it off ;)
Hi all!
With the help of you guys, I managed to build my own valve-caster. I used the Renegadrian layout without tone.
Overall, I like the tone, but I am not so convinced from the usability:
1. Sometimes I get some kind of oscillations
2. Its sometimes not very "direct"
So, I hoped to solve the problems by adding a buffer behind that thing.
Please tell me, what I did wrong:
I placed the buffer behind the volume Poti (was easier than before..)
I used a schematic from that page: http://www.muzique.com/lab/buffers.htm : the first schmeatic using an opamp (the one with only two caps, one resistor and one IC)
Instead of the TL071 I used a TL072 and connected my supply to pin 8 not pin 7.
Result: NO sound.... But if I disconnected the resitor, I do get a sound - but a very "bright" (in the negative sense) one...
What did I do wrong?!?
Is there any verified layout for the valve caster with buffer that I could use instead?
Thanks and regards!!
Quote from: Dongle on February 23, 2011, 04:01:31 AM
Result: NO sound.... But if I disconnected the resitor, I do get a sound - but a very "bright" (in the negative sense) one...
The resistor needs to be connected to "Vr" = reference voltage that is about half the supply voltage. Did you accidentally connect it to ground instead?
(http://www.muzique.com/images/buff7.gif)
I would suggest you add one more resistor and turn it into this buffer:
(http://www.muzique.com/images/buff8.gif)
Yes, I really did that mistake!!
Thanks a lot for pointing me at this!!
By the way: Is the TL072 appropriate for that purpose? I just had it there, so I used ist...
Does it make sense to use the second OPA for an "Input-buffer"? Or does it make no sense at all?
Quote from: Dongle on February 23, 2011, 05:29:23 AM
By the way: Is the TL072 appropriate for that purpose?
Yes perfectly!
Quote
Does it make sense to use the second OPA for an "Input-buffer"? Or does it make no sense at all?
It would make sense to use the second opamp as an output buffer. But you don't
have to use it.
Quote from: merlinb on February 23, 2011, 05:54:04 AM
Yes perfectly!
Thanks!
Quote from: merlinb on February 23, 2011, 05:54:04 AM
Quote
Does it make sense to use the second OPA for an "Input-buffer"? Or does it make no sense at all?
It would make sense to use the second opamp as an output buffer. But you don't have to use it.
Sorry, I did not get this fully. Does an Input buffer or an output buffer make more sense?
I thought an output buffer would be crucial, but an input buffer not?
I understand your post in the way, that it is the other way round...
Quote from: merlinb on February 23, 2011, 05:54:04 AM
Does an Input buffer or an output buffer make more sense?
Well, it would be nice to have an input buffer
and an output buffer. But if you have to choose, then I guess an output buffer is more useful in this instance, as it eliminates tone sucking due to cable capacitance and reduces noise after the pedal.
Quote from: merlinb on February 23, 2011, 05:18:32 AM
Quote from: Dongle on February 23, 2011, 04:01:31 AM
Result: NO sound.... But if I disconnected the resitor, I do get a sound - but a very "bright" (in the negative sense) one...
The resistor needs to be connected to "Vr" = reference voltage that is about half the supply voltage. Did you accidentally connect it to ground instead?
(http://www.muzique.com/images/buff7.gif)
I would suggest you add one more resistor and turn it into this buffer:
(http://www.muzique.com/images/buff8.gif)
my valvey is still homeless :(. But my real question is about the buffer you posted. Where would the buffer go in a standard vavlecaster layout? I am still new at this, so I hope this isn't a stupid question. I saw that you said it would be best to at least have an output buffer, but where do i connect it to? Does it go right before the 1/4" output jack?
Quote from: BarnyardBill on February 23, 2011, 03:44:06 PM
Does it go right before the 1/4" output jack?
Yes, so the opamp will ultimately be driving the following cable.
what is the purpose of the buffer?
The buffer does in generall compensate for differemt impedances. The output of the tube has a very high impedance, which is not good for a good signal transfer.
To make it simple: think of impedance as a resistor.
Both, your "source" (valvecaster) as well as the next thing in on your effect board (or the amp), has a "resistor": the valvecaster at the end, the amp at the beginning. If they would not have these resistors, you would not be able to put a voltage inside...
Now imagine, that your valvecaster has a very big resistor, but the next thing a very small one.
The valvecaster now tries to establish its normal output voltage, but is not able to do so, because the resitor at the other side is very small: thus, a very high current happens, but not a high voltage... you cant really use the full potential of the valvecaster.
On the other hand, if you have a high input resistor at the other side, you would get a high voltage -> more volume and different sound...
In principal, you would have to adapt the output resistors to every different device. As this is too complicated, you can also build such a simple buffer as shown before. The buffer is a "follower": it puts out the same voltage as it gets in the input, no matter how much current is flowing...
To summarize: a buffer
1. presents a controlled and constant load to the exit of the tubes
2. Sends the same signal as the input signal, no matter which device follows
EDIT: PLEASE corret me, if I was wrong. I am not so sure about all this stuff, but thats how I explained it to myself...
EDIT 2: The ideal effect would have a very high input impedance, so that it is very easy for the effect before (or guitar) to establish the voltage signal.
And it has a very low output impedance, beacuse otherwise the high input impedance of the next effect does not help... and it prevents the treble loss metioned by merlinb
Quote from: Dongle on February 24, 2011, 04:56:07 AM
The buffer does in generall compensate for differemt impedances. The output of the tube has a very high impedance, which is not good for a good signal transfer.
Further to what Dongle said, an output buffer also eliminates treble loss due to cable capacitance. The stock valve caster (and many DIY pedals) has high output resistance, so when loaded by some cable capacitance you have an RC filter that cuts treble. The greater the resistance, the lower the cutoff frequency of the filter. A buffer prevents this because it has a very low output resistance.
What's more, if you have a high output resistance then it is very easy for external hum to couple into the cable. A buffer eliminates this too, because its small output resistance shunts any such noise to ground.
If using a buffer there are a lot better opamps you can use than the TL071. like the OPA134, LT1351, LT1028, OPA1611, or TLE2071. current draw wouldn't be an issue since everybody is using wallwarts or power supplies
Thanks for the hint!
Why are they better for that purpose? I will try them...
Quote from: Dongle on February 25, 2011, 03:28:29 AM
Thanks for the hint!
Why are they better for that purpose? I will try them...
The main advantage is that some (all?) of them don't suffer from sudden phase inversion if the input signal swings close to the rail, unlike the TL07x, which could potentially happen in this pedal. Also, some of them are stable even with large capacitive loads, so could potentially drive super long cables. But then, so could a TL07x if you add a small resistor in series with its output.
Apart from that there aren't any other real advantages that I can see; gain, noise, bandwidth, slew rate etc are all either no better or irrelevant in this application.
so this will cut down on signal noise than?
Quote from: pazuzu on February 25, 2011, 11:33:03 AM
so this will cut down on signal noise than?
Adding an output buffer to a stompbox will reduce sensitivity to external noise, yes (mainly mains hum pickup). It can't remove noise that is already on the signal, of course. And unless you adapt the rest of the FX circuit, it can't improve the noise of the pedal itself. However, a sprinkling of buffers throughout an FX circuit may allow the designer to use much smaller resistances than usual, which is the number one way to improve the overall signal/noise ratio.
hmmm. ok thank you. my pedal is probably not gonna get much better, but i am planning to do a double like the on in your sig, and this time i will be breadboarding instead of just making it right out.
Hi guys!
Another question:
We does everybody control the gain pot at the anode and not at the cathode? You could also replace R2 with a pot and control the gain, right? What is the disadvantage here? Is there a different in sound?
Regards
Dobgle
The gain pot is already at the cathode, as you can see here (http://daniel.robert9.pagesperso-orange.fr/images/Triode.GIF) - never seen a gain pot at the anode...
Alright.. I mixed both up...
But the meaning is the same: I could also put a pot at the anode and control the gain with it. If I raise resistance, gain raises - only point is: If I have zero resistance, I have no sound... so, the gain pot should be in line with a fixed R...
i guess you could techniclt put a resistor in series with a 100k pot or something to the plate and vary the gain that way. The best way seems to be to put a pot in between the gain stages of the triodes. it goes right after the decoupling cap and into the following grid.
Hi , can this be used as a preamp ?
I've just gotten my one breadboarded up! After some tweaking to suit my humbuckers it sounds incredible! My only problem is that I'm getting no boost. In fact, it is slightly quieter than clean guitar even when I have the volume pot cranked. It was even quieter before I started tweaking so I'm presuming that's not the problem. The volume drop is roughly equal to the amount of compression I'm getting so when I'm playing quietly, the volume is about the same with the valvey in and out but when I'm really digging in there is quite a big difference in level. Here are my voltages:
Pin 1: 6.2
Pin 2: -0.25
Pin 3: 0
Pin 4: 0
Pin 5: 9.3
Pin 6: 7.5
Pin 7: -0.2
Pin 8: 0
Pin 9: 4.67
My tweaks are:
R1: 1M and 220k in series
R2: 470k
R3: 220k
C1: 27nF
C4: Removed
VR2: Removed
The resistor changes are all to get a bit more drive and the C1 change is to tighten up the tone a bit. If needs be I can make it up with the stock resistors and caps and remeasure my voltages. Any help would be much appreciated :icon_wink:
If you have anything on the brteadboard, you could also try a buffer!!
If your Amp does not fit the impeadance requirements of the valvecaster, that may be a good reason for your volume loss! You can stop it with the buffer.
Your mods give even more gain and should make the thing louder. So dont worry about that. The mods are good, I tried similar things. Thats for sure not the reason - but the impeadance might be...
EDIT: And you should also try 12 V - better 30 or 40! It makes a NICE difference - and gets louder ;)
Do you have active or passive pickups?
A buffer? Would a Boss pedal before and after do the job? They're buffered, right?
Yeah, that would do the job.
But in my first post I did not realize, that you are running with 9 V. My Vaövecsater had also low volumes with 9 V. If you can raise everything to 12, it will be much better!
If you can make it to raise the heating to 12 and the anodes to 30 or 40, it will be even better!!!
Passive p'ups and yeah I'm running it at 9v. I'll have a root around for a 12v wallwart. I was kinda hoping to get it going well with 9v because i'd rather not have to bring a second WW to gigs. Has anyone been able to get a volume boost or unity running at 9v?
Edit: I'll give the Boss before and after a go now too
In principle, you did the right things:
- higher values for R2 and R4 increase gain
Its a simple and good standard circuit - but if the heating is not sufficient and the voltage in the tube is not big enough, there is nothing you can do...
Quote from: Edalicious on March 07, 2011, 09:42:29 AM
Has anyone been able to get a volume boost or unity running at 9v?
You could always try a charge pump (MAX1044) with a 12V regulator after it to get your 12VDC from a 9V supply.
Did you try this? I am not sure, if a max 1044 gives enough current for the heating...
But it works for sure for the anodes! Best thing to do: 12 V wallwart directly to the heating. Try this first. After that, go and raise the anode V with a charge pump.
I am not using the 1044, but the 7660S. Its much cheaper and can also work with 12 V (up to 15). The 1044 only can handle 10.X V as input.
Ok, the buffered Boss pedals before and after made no difference to the level at all so I'm guessing making my own buffer probably isn't going to be much help. Would it be possible to use two 9v jacks to bring the voltage up to 18v and then reduce that voltage to 12 for the heaters?
Sure, that works!
Good luck :)
For trying, you can reduce the voltage with a voltage divider (two resistors). In a first trial, I would not use a 7812 for that..
Yeah that's what I was planning :icon_wink:. Would it be worth sending the full 18v to the anodes too? Would there be any problem having the two 9v dc jacks daisy chained from the same wallwart?
EDIT: Hmm, after some reading, it looks like I can't get 18v from one wallwart. It'll have to be the voltage pump so
Another way to brighten up the Valvecaster is to use a 500K or 1M for the tone pot. The tone pot is just a faucet to bleed out the highs to ground through the 10nF cap. A 500K or 1M pot gives you the option of darkening the sound or making it blinding bright, or somewhere in between. This can be an alternative to building a Valvecaster without a tone pot
This drawing of the Matsumin pedal is awesome, and very helpful! I finally got mine working today (using a cheap Sino 12AU7), but I noticed the tone pot is wired backward in the drawing, an easy fix though. I also tried it out with both 9v and 12v DC (using a Radio Shack adjustable wall wart), and both sound good, but I'll bet the 12v setting is probably better for the tube's health.
I hope to get a test video posted on YouTube soon. Thank you for making the nice drawings, they really help a bunch! ;D
Tim
Quote from: dano12 on December 13, 2007, 09:31:09 AM
Regarding the 386 amp, that's the route I'm taking with my wired tube socket thing. Trying to fit it in a small plastic case.
For the questions about using a tube other than the 12AU7, as said earlier, they are higher gain and won't work nicely unless you modify the circuit, I don't know how to do that part.
tubesandmore.com has the tube and sockets, it is the standard 9-pin tube socket you would use for guitar amp preamp sections.
Here is a rough *unverified* wiring diagram for anyone who wants to try it.
(http://www.beavisaudio.com/Projects/ValveCaster/MatsuminValveCasterWiring.gif)
I built my Matsumin Valve Caster in a Hammond 1590BB style enclosure (PedalPartsPlus.com, #1126), with an inexpensive Sino 12AU7 tube, some cloth insulated wire and the terminal strip from TubeDepot.com, and most of the capacitors and resistors from Mouser.com. Pots and knobs came from PedalPartsPlus.com, and jacks and DC power jack came from Mouser.com. You can see the 12AU7 tube filaments glowing in the 2nd photo while powered by 12v DC (I also had good results with 9v DC too).
(http://farm6.static.flickr.com/5134/5518405003_670febf64d.jpg) (http://www.flickr.com/photos/timpatterson/5518405003/)
Valve Caster pedal guts (http://www.flickr.com/photos/timpatterson/5518405003/) by Tim Patterson (http://www.flickr.com/people/timpatterson/), on Flickr
(http://farm6.static.flickr.com/5020/5519002354_749b0e8774.jpg) (http://www.flickr.com/photos/timpatterson/5519002354/)
12AU7 Tube Powered Overdrive Pedal - with glowing filaments! (http://www.flickr.com/photos/timpatterson/5519002354/) by Tim Patterson (http://www.flickr.com/people/timpatterson/), on Flickr
(http://farm6.static.flickr.com/5292/5518996552_8d7e9d91df.jpg) (http://www.flickr.com/photos/timpatterson/5518996552/)
Tube Overdrive Stomp Box (http://www.flickr.com/photos/timpatterson/5518996552/) by Tim Patterson (http://www.flickr.com/people/timpatterson/), on Flickr
You can see more photos of this build on my Flickr.com page (http://www.flickr.com/photos/timpatterson/sets/72157626086322521/).
i found the problem
here are the voltages at the pins
1- ~7v
2- (-0.5)
3- 0
4- 0
5- 10.7
6- 6.8
7-~(-0.3)
8- 0
9- 5.14
the voltage at pin 1 is way too big-how can i fix that?
why not with 12U7 tubes? they are designed for 12V car radio.
draw 150 mA though for the heaters.
tjp78704, that is AWESOME! :icon_eek: F...ING AMAZING!!! :icon_razz: OMG!!! I love it!!!
This seems to be something that i wanna build soon, can anyone that have one of these working upload a soundtest on youtube.... ? please...
I cant wait to hear what it sounds like...
I think your R2 mod might be the issue.. Have you tried the value called for in the schematic yet?
Quote from: red_92 on March 12, 2011, 02:21:28 AM
i found the problem
here are the voltages at the pins
1- ~7v
2- (-0.5)
3- 0
4- 0
5- 10.7
6- 6.8
7-~(-0.3)
8- 0
9- 5.14
the voltage at pin 1 is way too big-how can i fix that?
Hi,
during the last few days I built the standard valvecaster without any mods. The sound is (some others had this problem too) very low in volume. Gain and volume to max is a bit quiter than the bypass sound.
The parts are soldered to the tube socket. and there is no part connected with a wrong pin, everything is soldered the right way (I checked it again and again...).
Here are my pin voltages (I run this box with 9V):
1: 8,60
2: 0
3: 0
4: 0
5: 8,92
6: 8,72
7: -0,11
8: 0
9: 4,44
I tried to lower the voltage on pin1 like rick recommended on page 55 but I can't get lower than ~7V on pin 1 with a 1M pot instead of 220k (R2). The same problem with R3.
what layout did you use? pin 9 is usualy disconected. usualy heaters are wired w/ 9 volts to pin 5 and pin 4 grounded.
here is a sound clip as requested by some members. camera mic is not the best but you get an idea of what it sounds like. This is one of my first ones. http://www.youtube.com/watch?v=Lzucs8PRVgA
Quote from: zambo on March 13, 2011, 08:24:29 PM
what layout did you use? pin 9 is usualy disconected. usualy heaters are wired w/ 9 volts to pin 5 and pin 4 grounded.
pin 9 is not used, but is connected internally, so you will find half the voltage just because you give voltage to 4 and 5.
The 12AU7 heater filaments use 6.3v - 12v. See the specs, http://www.audiomatica.com/tubes/12au7.htm
Each filament is intended to run on 6.3v. The 12AU7 is a dual-triode, so it has 2 filaments (one for each half). So if you are running them in series (only pins 4 and 5) you supply 12-12.6v. You can also run them in parallel, 6.3v to pins 4 and 5 and wire up pin 9 as a common ground.
Basically, either way you do it you should ideally read something close to 6.3v from pins 4 to 9 and from pins 5 to 9. Although other voltages will definitely work, I've heard you can really reduce the life of a tube by going too much over (or under) the specified voltage.
Tim
Quote from: Dongle on March 07, 2011, 09:11:34 AM
If you have anything on the brteadboard, you could also try a buffer!!
If your Amp does not fit the impeadance requirements of the valvecaster, that may be a good reason for your volume loss! You can stop it with the buffer.
Your mods give even more gain and should make the thing louder. So dont worry about that. The mods are good, I tried similar things. Thats for sure not the reason - but the impeadance might be...
EDIT: And you should also try 12 V - better 30 or 40! It makes a NICE difference - and gets louder ;)
Do you have active or passive pickups?
I relsoldered the whole components including the pots and so on and I still got the same values on the pins. Maybe i should solder the resistors, caps etc. on a perfboard but I don't think it will help a lot.
Zambo: I used the pcbless layout drawn by dano from page one.
Is it possible that I killed the tube? Because I resoldered a cap with the tube inside the socket before I tested it the first time.
Edit: i forgot tho say that I'm using a ECC82 that's the european version of the 12au7 --> same specs.
I wired a 6 pos. rotary switch with different caps across the gain pot to get different tones. It sounds great but I was getting loud pops when I turned the switch. I wired 5.1M resistors across the switch to get rid of the pops similar to this pic
(http://i48.tinypic.com/ivl2md.jpg)
The pops are totally gone but now the Valvecaster is noisy. the noise wasn't there before I added the resistors. Is there a way to get rid of the noise? maybe a different way to wire the resistors to get rid of the pops?
Resistors make alot of noise .
Quote from: DavenPaget on March 15, 2011, 04:08:58 AM
Resistors make alot of noise .
Actually, I believe he chose to use resistors here in order to prevent switch "popping" when selecting between cap settings while the unit is ON.
Popping ? If there are popping noises , it's got to be arcing elsewhere .
Quote from: Govmnt_Lacky on March 15, 2011, 08:33:57 AM
Quote from: DavenPaget on March 15, 2011, 04:08:58 AM
Resistors make alot of noise .
Actually, I believe he chose to use resistors here in order to prevent switch "popping" when selecting between cap settings while the unit is ON.
Solution: Remove the 5M1 resistors and don't change the switch position when the pedal is on. It's unlikely that there will ever be a need to crouch down and alter the setting while in the middle of a riff!
That damn thing is going to move in a drawer and will never come back on my desk again...
I rebuilt it on vero on renegadrians layout and the voltage values are same as before. I used 1m pots for R2 and R3 but I couldn'tmanage to get lower than 7V on Pin1 and Pin6.
http://www.aronnelson.com/gallery/main.php/v/Renegadrian/Valvecaster+v0_5.jpg.html
Next step: order a new tube.... :D
Quote from: tuckster on March 15, 2011, 02:12:44 PM
That damn thing is going to move in a drawer and will never come back on my desk again...
I rebuilt it on vero on renegadrians layout and the voltage values are same as before. I used 1m pots for R2 and R3 but I couldn'tmanage to get lower than 7V on Pin1 and Pin6.
7V sounds pretty reasonable to me...
Well I tried to get to the values that Rick postet:
Quote from: frequencycentral on March 24, 2009, 12:37:38 PM
Yup, your pin 1 should be 25% of the power supply voltage - about 2.3v in your case.
Your pin 6 should be 66% of the power supply voltage - about 6 volts in your case.
This seems to be a common debug problem with Valvecasters - the plates being too high.
Those voltage of mine that Adriano posted were taken with the gain set to maximum (ie first stage cathode grounded) by the way.
If you are sure everything is correct (though it can't be if your voltages are off), you could replace the 220K resistor with a 1M pot (use the pot's lugs 1 and 2) and tweak it until you read about 2.3v at pin one. Then measure the resistance between lugs 1 and 2 of the pot. Do the same with the 100K at pin 6, though I think pin 6 will come into line when you sort out pin 1.
This is not possible with my build. I wonder why so many people have correct values and on the other side there are still so many people in this thread with values like mine. And I still talk about 9V not 12V.
I don't get it.
@tuckster
Not trying to but in, but I just finished mine, and with my 9V wall wart and 9 Volt Batt, I had similar results as you. I now am running a 13.5v with voltage regulator and I get 11.79 and more volume.
Mine had big issues with hum, not matter what I did with power, I broke down and bought a adjustable wall wart from Radio Shack (13.5 and 30V) so I can play with higher voltages.
So I do not think your readings are bad, As a matter of fact one of my EH Tubes sounds awesome at those levels, but my other three, not so much.
I'll check my pin one and see what I get on it.
Ok now it works. I don't know why... I put in a new Pot for R2 becaus ethe last one was realy burned after all these resoldering adventures.
I still got the same pin values for 9V and it also works for 12V but then I obviously have different values.
I tinkered around with R2 and R3 to get a nice sounding pedal. I'm going to post the pictures in the pitures thread.
hi guys! DIYstomps newbie here! :)
just finished building the Valvecaster (pcb-less), used a 12AU7, will take pics tomorrow after putting 'em altogether in the enclosure.
btw guys, try to change C4 to a 22nF one for a more use-able tone control
(dunno if this was already posted before).
anyway, many thanks to the contributors in this thread, and to matsumin himself! :)
Welcome and congrats on your build! @ Tuckster- Glad it worked!
Hi guys!
I encountered a new problem: I am running the valvecaster with 30 - 40 V (7660S, PIN 1 connected) and a buffer (OPA2134) at the output.
If I adjust my potentiometer to high gains (low resistance), I get a steady tone. Very annoying. It starts quite abrubtly on a certain gain level.
Any ideas how to get rid of this? Does anyone else have this problem?
if its a high pitched squeal or wistle kind of sound its oscilating. Welcome to tube distortion....check your layout and start replacing input wires and signal wires with sheilded wire. only ground the sheild on one side. usualy the side away from the noise (input side etc.). Thats all I can think of. you could start adding grid stop resistors but those suck the tone i think. a cap to ground from the plate works for the excessive highs. 500 pf caps work well for that but once again you are killing tone. try to solve it with better layout if you can. higher voltage makes higher volume and more gain. This design is really for lower voltage. you start getting all these squeals and stuff as you raise it. Good luck, hope that helps. Greg
Well, its not oscillating. It is a steady tone. Quite constant.
I would like to post soundfiles, but I lent my recording device to so and will get it back next Tuesday... So long time to wait. In the meantime, I will breadboard the thing again and make sonme tests - like adding grid stoppers, raise resistor at Pin 8.
I will try without adding high cut filters.
I will keep you updated!
QuoteWell, its not oscillating. It is a steady tone. Quite constant.
Is it very high-pitched? I built a circuit using a 7660S, and even with pin 1 connected to raise the frequency of the chip, it was running at 16-17KHz. I couldn't hear it, but it was a deafening loud high-pitched tone to my 11-year-old. I thought the 7660S would be a drop-in replacement for the MAX1044, but it wasn't. Using a real MAX1044 with pin 1 connected actually raised the frequency above the range of hearing.
Thanks for the hint! But the oscillation frequency of the 7660S with PIn 1 connected is 35kHz - I think, even your son is not able to hear it.
The pitch I am hearing is for sure below 10kHz - I even thik belo 5 kHz. I will try to find an app to measure the frequency and post again..
QuoteThanks for the hint! But the oscillation frequency of the 7660S with PIn 1 connected is 35kHz - I think, even your son is not able to hear it.
The pitch I am hearing is for sure below 10kHz - I even thik belo 5 kHz. I will try to find an app to measure the frequency and post again..
What I saying was that even though the 7660S with pin 1 connected is SUPPOSED to run at over 30KHz, the chips I had were NOT.
If your tone is 5 or 10KHz, is it possible that your frequency boost pin is not really connected (to V+ right?) ?
Is it possible that you have a 7660 instead of a 7660S?
Is it possible that you have a chip MISMARKED as a 7660S that is really a 7660?
Lots of things are possible... I am not very into the industrial production and labeling of chips. But I just found an app for frequency measurements and will try this night.
Still, I think it is more likely, that my design is not so perfect because, if it was the chip: I would not only have this tone with high gains (I guess?!?), but always?!?
I will post the frequency tomorrow. Also, I will continue breadboarding and try some things like gridstoppers...
Thanks!
QuoteI am not very into the industrial production and labeling of chips. But I just found an app for frequency measurements and will try this night.
OK. Let us know what you find. I'm planning to build this also, and am very interested to see what you end up with. Can you post the schematic for your current implementation?
I may way off-base with my conjecture about the source of your problem. How are you getting 30-40V out of the 7660? Starting with a high voltage (15 or 20) and doubling, or multiplying with additional diodes?
One more theory involving the frequency of the VR... According to the Intersil ICL7660S datasheet:
"Since the ESRs of the capacitors are reflected in the output
impedance multiplied by a factor of 5, a high value could
potentially swamp out a low 1/f PUMP
x C 1 ) term, rendering
an increase in switching frequency or filter capacitance
ineffective. Typical electrolytic capacitors may have ESRs as
high as 10Ω.
"
Are you using high-ESR caps? Is it possible that turning up the gain is somehow "rendering an increase in switching frequency or filter capacitance ineffective"?
Sorry for my long silence... I was too busy at work. But yesrterday I could take have an hour for breadboarding everything.
Result: NO anoing sound anymore...
I am not sure what happend... I only had few changes:
1. No input buffer (I am quite sure, that this is not the reason)
2. No LCL-filter of the power supply: might be the reason, if I chose wrong values, so that it started oszillating
3. reduced gain pot from 100 k to 50 k and connected Pin 1 with Pin 2
4.. I used schotky diodes - no idea if this can be the reason...
I will keep you updated...
To your questions: I am using "normal" electrolyt caps.
I am getting the high voltage by using about 11 V for input, and cascade the diodes and caps: always start with diode, than cap between diode and PIN 2, another diode, cap to ground, diode, cap to pin 2, diode, cap to ground, ...
After each stage, you get 2 * input V - diode V. But its not "multiplying, but always adding the inout voltage.
see how your bread board signal routing is and then compare to how you have it in the enclosure. layout can be pretty annoying with these types of devices. another thing you can do is when the thing is on and oscilating take a wooden chopstick or drum stick and move wires carefully to see if it changes or stops the offensive sound. got to be very careful though. one hand in pocket, thick rubber soled shoes, not standing in shower etc.
in case anyone is interested, here is my first recording test of my valvecaster. Its in a Cheap Radio Shack ABS box. http://www.youtube.com/watch?v=kgKxwAIpK78 (http://www.youtube.com/watch?v=kgKxwAIpK78)
I have the super overdrive in front as it kills some buzz I am getting as its not on. With the plastic case I was having issues with the iron melting plastic so some of my grounds may have cold joints.
Its 12v (11.9 after rectifier) running a HE 12Au7. I changed the .047 to .022 and I put a red led under the tube to know when I have the pedal enabled. The tube always gets power
the amp is a Vintage 16 unmodified with the cestion vintage 30 speaker, reverb is @ 1 or 2 set to 5 watt triode mode
I have a high pitch noise at higher volumes, which I belive is the ground. the overdrive before it kills some of that.
I am awaiting a hammond case to fix my lay out (more room and it does not melt.. ;D),
Gain is set to 75%, vol 100% and the tone pot is replaced with a 100K resister.
Quote from: zambo on March 23, 2011, 10:32:28 PM
see how your bread board signal routing is and then compare to how you have it in the enclosure. layout can be pretty annoying with these types of devices. another thing you can do is when the thing is on and oscillating take a wooden chopstick or drum stick and move wires carefully to see if it changes or stops the offensive sound. got to be very careful though. one hand in pocket, thick rubber soled shoes, not standing in shower etc.
YES. Noise (frequency) changes, if I move the cables. Shit. How do I find a "good" layout?
Yesterday I managed to add my LC-filter to the breadboard: Still no noise. So it s not the filter. The gain pot was also not the reason...
I also found out, that it is definitely NOT the charge pump. So it probably has something to do with the signal routing. I don't like this...
Does anyone have a nicely routed layout with 40 V???
Thanks for your help!!!
Dongle
try using sheilded wire for your signal path. only ground one end of the sheild and make it the end near the input. keep the input far away from the output. keep the signal wires from running next to each other for long runs. make all your wires cross at 90 degrees as much as possible. i dont have a layout to offer , but if you use a little bigger box it helps. give things a bit more room. if none of that helps then put a small ceramic cap from the plate to ground on pin 1. 500 pf should be good but this is killing off some highs and i hate doing that. also if you use a .002uf input cap it tames the lows a lot more. hope that helps.
Finally!!
I
1. used shileded cables for signal pass,
2. soldered every possible thing on the tube socket to keep distances short
3. Spend some mor thoughts on where to connect the grounds...
NOW IT WORKS!! SILENCE!
Thanks to all!
Here is my completed build.. I have two mess ups I need to fix
Running on 30 volts, has a lm317 for regulating heaters.
Using a JAN/PHIL 5751 as the 12Au7 sounded harsh at this voltage for some reason..
I have to fix the tone cap I put in a 1uf my mistake (the diffrence between 103 and 104 on the green caps is hard to read after 1am.. :icon_mrgreen:
Changes
30 volts (DC as AC creates a loud humm, even with the full bridge rectifier)
coupling's cap and plat to Grid cat at .022
100K resister instead of a tone pot.
you can see this is tight and I should have soldered things directly to the socket before installing it..
the rectifier and 317 are at the left
I needed more heat shrink.. (http://dl.dropbox.com/u/14312589/TubbyTube/IMG_3107.JPG)
Will post to youtube latter the sound.
(http://dl.dropbox.com/u/14312589/TubbyTube/IMG_3105.JPG)
(http://dl.dropbox.com/u/14312589/TubbyTube/IMG_3106.JPG)
Can anyone verify if this schematic is correct?
Here it is:
(http://i.imgur.com/L3juT.png)
Anyone want to figure out where I went wrong too? Volume works, but I just get a hum if I max it. Sounds a bit like when you ground a guitar cord. No signal from my guitar at all.
Here's my attempt:
(http://i.imgur.com/qdb6d.jpg)
(http://i.imgur.com/m82wZ.jpg)
Pinout is as follows
pin1 6.5
pin2 -1.16
pin3 -----
pin4 -----
pin5 13.33
pin6 8.5
pin7 -1.22
pin8 -----
pin9 6.6
I'm using a 12v wallwart with 300ma rating
From the looks of the pinout, it should work. The heaters are nice and bright. Tried several different au7 tubes. When I switch the pedal into bypass (footswitch off) it lets my guitars signal through fine.
As you may have read in the long thread, the Valvy needs a stable regulated power supply with enough current - take a 12V 500mA or better 1A and use 78T12 or 7812 and a filter cap (at least 100µ)
Think I need a vacation...I read The haters are nice and bright. And the HATERS GONNA HATE came to mind.
(http://www.olaolaonline.net/thumbs/20110407150113p_heaters_tn.jpg) (http://www.olaolaonline.net/page.php?image=20110407150113p_heaters.jpg)
Quote from: Renegadrian on April 07, 2011, 08:49:00 AM
As you may have read in the long thread, the Valvy needs a stable regulated power supply with enough current - take a 12V 500mA or better 1A and use 78T12 or 7812 and a filter cap (at least 100µ)
Tried a 7812, but I'll try it again with a higher ma ps. Can you point me to what page of this thread listed the cap placement and rating? I've read probably 30-40+ pages, but it's a little daunting to try to read all 112.
Quote from: Renegadrian on April 07, 2011, 09:07:39 AM
Think I need a vacation...I read The haters are nice and bright. And the HATERS GONNA HATE came to mind.
(http://www.olaolaonline.net/thumbs/20110407150113p_heaters_tn.jpg) (http://www.olaolaonline.net/page.php?image=20110407150113p_heaters.jpg)
lol
Alright I changed my ps to a 12v 4amp filtered ps. Should be more than enough. Also added a filter cap (100uf) per the instruction on page 18 (positive and negative lead of the incoming power).
Pinout:
pin1 2.19v
pin2 -0.35v
pin3 -----
pin4 -----
pin5 11.82v
pin6 3.70v
pin7 -0.30v
pin8 -----
pin9 5.87
Can anyone give me what the voltages should be on the pots or anywhere else?
Now I'm getting no hum. Tube warms up (albeit a little less, but still nice and toasty), led turns on when pedal is 'on' and heaters still cherry red. MAKE SOME NOISE NOW!!!!
Something that MAY help with this thread:
Posting some KNOWN GOOD voltages would go A LONG WAY!!!! ;D
Voltages based on a regulated 12V supply. I lost count of how many posts are on this thread regarding voltages taken. If they had some "DEFINITE KNOWN GOOD VOLTAGES" to compare with, it may have saved 20-25 pages of this thread :icon_eek:
Just my 2 pennies! ;)
That' s what Rick - frequencycentral posted a while back, using a stock ckt.
Here's voltages taken from my working Valvecaster, which I run at 12 volts:
Pin 1: 3.02v
Pin 2: -0.518v
Pin 3: 0.00v
Pin 4: 0.00v
Pin 5: 11.97v
Pin 6: 8.21v
Pin 7: -1.285v
Pin 8: 0.00v
Pin 9: 5.91v
Nice to know you got no hum! bingo!
I'm really sorry for not reading this WHOLE thread, but has anyone tried this build with 12U7 dual preamp tube designed to actually run at a full voltage of 12V?
@drbob1
yes.. lots... starting about page 2. Mine is running @30V with a 317 regulating the heaters at 12v
@everyone
my pedal is for the most part quiet as longs as I have a good clean power strip. But twice tonight I started to hear radio when the pedal is engaged. So while its nice to keep up with the baseball scores.. everything has its time.. any suggestions on how I could supress this? maybe add a cap to the input jack?
Thanks
Quote from: Renegadrian on April 07, 2011, 06:53:43 PM
Nice to know you got no hum! bingo!
Well I've got no hum, but also no signal from my guitar when this thing is on. Can you or someone else take a look at that circuit I posted and verify if that layout is even correct?
I've went over it quite a few times and still can't find issue with the connections or components (most of which I replaced already once and will do again while trying a new layout).
Anymore suggestions, like how to get my pin6 and pin7 values a little closer to ricks? (change resistor values?)
I'm pretty sure that schematic was just missing a ground wire on one of the tube pins ::)
Tried out the "no-tone" version and it worked with my breadboard, so I tried my tube socket with the parts soldered directly and it worked. Unless one of the few other components involved were bad, I can't see why it didn't work previously. I might try to correct the schematic later so that others won't toil endlessly...
Little noise maker sounds great, just need some white paint and I'll post a few pictures. Not too shabby thanks mangs! :icon_mrgreen:
Can I say BINGO now!? :icon_lol:
@ iccaros you could try a cap from + to - on the input jack. I would use like 500pf or so. maybe smaller.
@iccaros:
I'm not sure you realized that wasn't a typo? The thread (I read the first 10 pages or so) discusses using a 12AU7, a tube designed to run a 12v heater and 200+ volt B+. Running at even 30v is considered a starved plate design and is far out of the operating range for the tube, resulting in most of the pedals I've played having a harsh type of distortion.
The 12U7 tube, along with the 12K5 power tube, were designed for car stereos, to run at 12v heater and 12v B+ in "space charge" mode. So I wondered if anyone had used a 12U7, not a 12AU7 in this circuit? I did try a search, but so far all the mentions I've seen of the 12U7 are typos for 12AU7.
Thanks for your patience...
it seems like i saw something about a 12u7 but i cant remeber what. I think their was an issue with the amount of current through it??? maybe?? I just cant remeber though. i know the sopht amp uses something like that though.
Quote from: drbob1 on April 08, 2011, 11:44:11 PM
@iccaros:
I'm not sure you realized that wasn't a typo? The thread (I read the first 10 pages or so) discusses using a 12AU7, a tube designed to run a 12v heater and 200+ volt B+. Running at even 30v is considered a starved plate design and is far out of the operating range for the tube, resulting in most of the pedals I've played having a harsh type of distortion.
The 12U7 tube, along with the 12K5 power tube, were designed for car stereos, to run at 12v heater and 12v B+ in "space charge" mode. So I wondered if anyone had used a 12U7, not a 12AU7 in this circuit? I did try a search, but so far all the mentions I've seen of the 12U7 are typos for 12AU7.
Thanks for your patience...
@drbob1
Got ya,
If I can get my hands on one I am willing to try...
But all Pre-amp distortion can sound harsh. I changed to a 5751 and it killed a lot of harshness but I am working on a tri-pedal based on the firefly amp design but at 30 - 60 volts. In this case the final tube is on more of a power amp configuration and power amp overdrive is the nice "tube" overdrive most people are looking for.
What I do not like about this design is that is changes bias of the tube to create a situation where the grid is less negative than the cathode. The bias should be fixed with the "gain" between stages.
I use it currently to drive my Carvin Vintage 15 into more of a metal realm, so I can do more with the amp.
With the firefly design I am hoping I can place this in front of any amp and get from a clean tone, the distortion I want.
So back to your thought, If the tube is made to run @ 12 volts.. Then I would place the gain control between the anode(pin 1) and the Grid (pin 7) and I would probably make a two tube design, with the second being driven to overdrive by the first.
@drbob1
now you have me intrested
I found this site
http://www.sophtamps.ca/mambo/index.php?option=com_content&task=view&id=25&Itemid=37
and Tubedepo has the tubes.. All NOS, so that means I would have to buy a few to ensure I had enough when they die....
This runs so low it could be a pedal or a small amp, I guess a impedance switch would be needed. but I'm game.. but this is off topic for this thread, so should we start another?
;D Thanks Renegadrian
(http://i.imgur.com/CIqfZ.jpg)
(http://i.imgur.com/zMG9h.jpg)
(http://i.imgur.com/PHP2k.jpg)
Hell yeah! :icon_twisted: me likes it!!! :icon_wink:
could I run this off 48v phantom power; If I used a 12v voltage regulator for the filament?
Quote from: a soBer Newt on April 15, 2011, 08:49:17 PM
could I run this off 48v phantom power; If I used a 12v voltage regulator for the filament?
I very very much doubt 48v phantom power would have enough juice to power the tube heater which requires 150ma. In fact, I do more than doubt.....
Hey guys, I'm slowly acquiring all the parts to build this. Just waiting on some sockets and an enclosure. I'm planning on building a single valvecaster with a switchable pentaboost into one enclosure. My plan is to run it all off a 24v Electro Harmonix power supply from Amazon. It doesn't state the amperage, but I assume since it is made for their beefier pedals, like the memory man and worm, that it should be fine in this application. (do you suppose that since it's expressly manufactured to power pedals that it would be well filtered and regulated straight away?)
I'm wondering, since the 5672's require 1.25 volts to the heaters, can I go:
24v --> lm7812 -->12AU7 heaters
`--> lm317 --> 1.25v --> 5672 heaters
With the 24v going to the plates of both tubes? I think I can track down a 7824 to regulate the 24v.
Does that sound... sound? I'm assuming that putting 24v into the lm317 and regulating it way down to 1.25v would require a ton of heat dissipation, right?
EDIT: Also, is it just the lm317 that requires at least 3v over its output to work? Or are the 7812 and 7824 in the same boat?
(by the way, I went to my local brick and mortar electronic supply to see if by chance they had any tubes, and the guy of course said their stock of 12AU7's and the like have been long gone; just for kicks, I asked if they had any 5672's, and lo and behold, they actually had two NOS Tung-Sol tubes! for 7 bucks a piece no less! These should be rad!)
Sorry to bump this, I just don't wanna buy those 7824's tomorrow if they'll do me no good.
Thanks for all the awesome support throughout this thread guys.
QuoteAlso, is it just the lm317 that requires at least 3v over its output to work? Or are the 7812 and 7824 in the same boat?
2 volts for the Fairchild LM7824.
Blast! Thanks for the info though!
For nice, quiet, behaved sound from this tube design, I'm going to need a nice regulated voltage going to the plates, right?
So would using an unregulated 24v to the plates for headroom's sake be better or worse than 18v regulated?
Just try.
You dont need it regulated. Stabilized is enough. So just put an LC filter there and it should be fine.
I dont know, why so many people are trying to "filter" with 7812 and similar stuff...
7812 is not a filter! You still can get ripple voltage out of this. I agree, in most cases ripple is reduced, but its much more effort than just putting an L and a C somewhere...
Quote from: Ratbones on April 16, 2011, 10:35:23 AM
My plan is to run it all off a 24v Electro Harmonix power supply from Amazon. It doesn't state the amperage,
If you mean this one:
http://www.amazon.com/Electro-Harmonix-US24DC-100-24V-Power-Supply/dp/B0042RHT4M/ref=sr_1_1?ie=UTF8&s=musical-instruments&qid=1303290789&sr=8-1
It is rated for only 100mA, so it does not have enough juice for this project.
I see, so I really only need to use the regulators to drop the 24v down to heater voltages pretty much. That simplifies things a lot. Thanks for the reply!
EDIT: Didn't see the post above... Damn... Why didn't I think to CLICK the picture... I guess I assumed if it's hefty enough to run those pedals it should do fine! Foolish...
You can also try a voltage divider... (2 x R)
I got mine all put together and working :)
Need to test some different tubes, as it sounds great as a clean boost with the gain dialed down, but I don't care for the breakup it gives me. Hopefully I can find a tube that has a nicer crunch to it. I only have AT7s at the moment, but have some AU7s on the way. It sounded pretty good with an old GE 12AT7 in it, but I didn't have a tube protector on it and crushed it when I stepped over my pedal board :icon_redface:
I have the plates running at 27v, I am using an HP deskjet printer adapter for power (I have 3 of them ) they have 15v and 32v outs. so the 15v line goes through a 7812, and the 32v line goes straight to the plates. Great little pedal ;D
Great thread!
hi there,
can i ask you what transformer u recomend for the valvecaster because alla i try 9-12-17 V 500 ma or higher where humming like hell.. :-\ With a 9V battery i have decent volume but for 30-40 min
tnx
I like 1spot 9v adaptors. they are quiet all the time. I had bad luck with adjustables as well. I have had boss and dan electro ones work as well.
Quote from: Brian_L on April 20, 2011, 12:41:45 PM
I got mine all put together and working :)
Need to test some different tubes, as it sounds great as a clean boost with the gain dialed down, but I don't care for the breakup it gives me. Hopefully I can find a tube that has a nicer crunch to it. I only have AT7s at the moment, but have some AU7s on the way. It sounded pretty good with an old GE 12AT7 in it, but I didn't have a tube protector on it and crushed it when I stepped over my pedal board :icon_redface:
I have the plates running at 27v, I am using an HP deskjet printer adapter for power (I have 3 of them ) they have 15v and 32v outs. so the 15v line goes through a 7812, and the 32v line goes straight to the plates. Great little pedal ;D
Great thread!
Brian
I was just doing some test with some 12Volt tubes I have been working on an amp with. the 12u7 (not a miss type) and the 12AE7. Both meant to run at 12V (12.5 with 12.5 heaters). they both sound as good, if not a better overdrive not so squashy.. as 12AU7 at 12 volts. But move to ~25 (no more that 28 as 30 is max plate voltage for these tubes), and amazing sound.. I played for over an hour going back and forth. The 12AE7 sounded best. This plate starvation design produces a harsh distortion, this is why you see a lot of people going to higher voltage. But with these tubes, which were made for car radios.. Well they rock. With the 12AE7 I can get a nice TOOL, even could do some rage like distortion at max gain. Since it has two different triode types, a beginning low gain section and a higher gain section, it sounds more like a power tube overdrive..
just what I have learned over the last two weeks.
In my 30volt I also use a 5751, known as the preamp tube of choice for SRV..
I like the 12AE7 the most.Best sound, more dynamic range as its in its element.
The only downside, the 12AE7 takes .4 amps for heaters. The 12U7 takes 150MA for heaters. So with my little pedal (size) and using a 12V regulator on the heaters, using the pedal case as a heat sink, well it gets hot drawing that much current.. It can handle it.. I hope.. But its wierd picking up a pedal and it is very warm
hi i am new to fx building and my valvecaster is not a booster but an unbooster even with all pots at max there is less volume ?
can anyone check my build for mistakes
muckey pup
(http://s1118.photobucket.com/albums/k607/muckeypup/)
http://s1118.photobucket.com/albums/k607/muckeypup/
no pic?
(http://://static.pbsrc.com/flash/rss_slideshow.swf"%20flashvars="rssFeed=http%3A%2F%2Ffeed1118.photobucket.com%2Falbums%2Fk607%2Fmuckeypup%2Ffeed.rss"%20type="application/x-shockwave-flash"%20wmode="transparent"%20/><a%20href="http://photobucket.com/redirect/album?showShareLB=1"%20target="_blank"><img%20src="http://pic.photobucket.com/share/icons/embed/btn_geturs.gif"%20style="border:none;"%20/></a><a%20href="http://s1118.photobucket.com/albums/k607/muckeypup/"%20target="_blank"><img%20src="http://pic.photobucket.com/share/icons/embed/btn_viewall.gif"%20style="border:none;"%20/></a></div>)
sorry i canot get the pic to show?
but you can use the link
thanks
muckey pup
(http://[img]http://i1118.photobucket.com/albums/k607/muckeypup/caster.jpg)[/img]
http://i1118.photobucket.com/albums/k607/muckeypup/caster.jpg
Quote from: Brian_L on April 20, 2011, 12:41:45 PM
I have the plates running at 27v, I am using an HP deskjet printer adapter for power (I have 3 of them ) they have 15v and 32v outs. so the 15v line goes through a 7812, and the 32v line goes straight to the plates. Great little pedal ;D
Great thread!
How did you get those HP printer adapters to work? I have 3 of them laying around and all I got was a loud hum when I used them
I don't get any hum, I have the 15v going through a capacitor/7812/capacitor setup, and it's really clean
Actually the output is powering all my pedals at 12v
no one
Hi all people, I´m new here....
7 days & 7 nigt reading 114 pages, more pics, and youtube video, about Valvacaster. I´v saw some people pin point components to the socket, other on PCB, many wiring cable (large or short). My question is: there are any sound diference (or also interference, hum, hiss) using long wires?
Quote from: muckey pup on April 28, 2011, 04:19:44 PM
sorry i canot get the pic to show?
but you can use the link
thanks
muckey pup
(http://i1118.photobucket.com/albums/k607/muckeypup/caster.jpg)
Pretty tough to debug a photo, got any voltages for us?
Does anyone know of a good perfboard layout for the valvey? I am accustomed to perfboard, but translating a vero board can be tough. Please Help
hello...i have heard about warming out tubes on amps....do we need to warm up this tube too?
@muckeypup.
at a glance i see your using those metal dc sockets....they can give you grief with a tip negative pedal...
it did on my pedals when i tried them, use plastic (isolated) ones... :icon_cool:
just a thought!....
Quote from: deadastronaut on April 30, 2011, 07:38:55 PM
@muckeypup.
at a glance i see your using those metal dc sockets....they can give you grief with a tip negative pedal...
it did on my pedals when i tried them, use plastic (isolated) ones... :icon_cool:
just a thought!....
+1
I used those jacks on the first ever pedal (Uglyface) I built. It lived in a plastic enclosure for a while, and I had a terrible time finding out what was wrong when I boxed it up in an aluminium Hammond for the first time !!
voltages
using a raytheon 12AT7wb
at 9v
p1, 7.56v
p2, -0.39v
p3, 0v
p4, 0v
p5, 9.3v
p6, 8.27v
p7, -0.48
p8, 0
p9, 4.6v
and at 12v
p1, 9.79v
p2, -0.65v
p3, 0v
p4, 0v
p5 12.33v
p6, 10.59v
p7, -0.71v
p8, 0v
p9, 6.12v
the peddle is working but at 9v its a unbooster with less vol than bypass when all
pots at max
at 12v it is about the same vol ass the bypass with slightly more gain
there is no buzzing or poping and the led lights when peddle is on
led is supper bright dose this mater
i have removed the powre socket and its the same
am i expecting to Mitch boost from the pebble
the ones Ive seen on youtube seem to have a tun of boost
boom
i just tried a direrent tube (mulard 4024) and wow Babb
what a peddle
in to my mini mat it screams, and loads of gain and vol and
a real good eq i need to start on a twin castert today
thanks every one who replyed
muckey pup
and a jan 5814a sounds amazzzzzzzing :icon_twisted:
@muckeypup..
soundclips?.. :icon_wink:
dose Anny one know what these things are like on tube life
at 12 v or 9v
should i use my precious nos tubes or get some jj to burn?
ill do sound clips on tus afternoon as every one in my house is
already pised at the noise and ill need them out to crank some
of the amps :icon_rolleyes:
ill try it the mullard 4024 and jan5814a
Quote from: dano12 on December 11, 2007, 07:51:24 PM
(http://www.beavisaudio.com/Projects/ValveCaster/MatsuminValveCaster.gif)
hey...i have read that this circuit is also good with 12v...
i am thinking of building this with 18v...would this be ok or would this burn the tube?
also what current is this circuit ''eating''? ;D
18 volts is fine for the anodes but not for the heaters. You would need to wire it so r 2 and r 3 are not connected to the heaters. They only want 12.6 volts max. otherwise yeah 18 volts sounds good and gives more volume boost and clean headroom. I like to run about 45 volts on pins 1 and 6. I knoe the heaters eat about 150 ma. the rest probably easts 10 to 20 i think.
Quote from: zambo on May 02, 2011, 12:45:02 AM
18 volts is fine for the anodes but not for the heaters. You would need to wire it so r 2 and r 3 are not connected to the heaters. They only want 12.6 volts max. otherwise yeah 18 volts sounds good and gives more volume boost and clean headroom. I like to run about 45 volts on pins 1 and 6. I knoe the heaters eat about 150 ma. the rest probably easts 10 to 20 i think.
what pins are the heaters?
basicly what's up with the heaters?they pre warm the tube or something?
thanks! ;D
Could I run a charge pump circuit in PARALLEL with my 12VDC input so that I could
A) Power my heaters with 12VDC (with the direct feed from the DC jack)
B) Power my plates at a higher voltage from the charge pump
C) Still keep the the current draw below ~200mA since the power feeds are in parallel.
Am I correct?
Quote from: tasos on May 02, 2011, 07:43:12 AM
Quote from: zambo on May 02, 2011, 12:45:02 AM
18 volts is fine for the anodes but not for the heaters. You would need to wire it so r 2 and r 3 are not connected to the heaters. They only want 12.6 volts max. otherwise yeah 18 volts sounds good and gives more volume boost and clean headroom. I like to run about 45 volts on pins 1 and 6. I knoe the heaters eat about 150 ma. the rest probably easts 10 to 20 i think.
what pins are the heaters?
basicly what's up with the heaters?they pre warm the tube or something?
thanks! ;D
Heater make the tube work. A tube is a thematic device. Meaning with out heat it does not work. The heaters (filament) heats the Cathode, causing electrons to literary boil off. The grid attracts or repels the electrons, based on its charge.
copy this and put in your back pocket http://www.hnsa.org/doc/neets/mod06.pdf (http://www.hnsa.org/doc/neets/mod06.pdf)
as for voltage tube heaters are designed for 6.3 or 12.6 depending on how you run them. There are two in this tube, so if you run from pin 4 to pin 5 you are running both tubes one to the other. each are about 42ohms (12au7) in resistance 12.6/.150 (important to know if you want to create a voltage divider to run the tubes, which I calculate to about 70ohms to get ~12volts from wire Plu voltage 70ohm Pin 4 flows through pin 5 to ground ) . if you run from Pin 4 and Pin 5 to + voltage and pin 9 to ground you are running parallel and you will pull .300 amps or 300 milliamps
Tube heaters in most cases are rated at +/- 20%, but most are not tested beyond +/- .6 volts. If you run at ~12 you will be fine. With lower voltage the tube will last longer but you loose performance, as long as you do not cause cathode striping.
Too high and you can burn out the heater coil.
oh this is great!
here is my though...could i run the tube with a voltage doubler and [18v] and the heaters with 9v ?
Quote from: tasos on May 03, 2011, 07:47:49 AM
oh this is great!
here is my though...could i run the tube with a voltage doubler and [18v] and the heaters with 9v ?
Heaters will work @9 but you risk cathode striping. you could run parallel heaters @ 6.3 volts. A 22 ohm resister should get you there.
When you run 9 volts each heater wire only get 4.5volts as they are in series.
So I would connect a 11.3ohm 1 watt resister to pin 5 and 4 and connect pin 9 to ground would get you 6.3 volts. a 10ohm would get you 5.8 volts (within +/- .6)
10ohm 1 watt
+18volt ---WWW----(Pin5 & Pin4)
Ground ------(pin 9)
If you change tube types this could change, calculate the resistance of the tube by calculating rated voltage/ rated current
so a 12AU7 says it is good in serial connection @ 12.6v drawing .150 amps (150 milliamp) so 12.6/.150 = 84 ohms. so in parallel they should be 21 ohms (1/ 1/r1+1/r2, plus they are the same value so the 84/#of resisters of the same value = 42 ohms each wire, so in parallel, like speakers that is 22ohms) but we also have the datasheet which tells up that a 12AU7 heater in parallel pulls .300 amps @ 6.3 volts so 6.3 / .300 = 21.
if you change tube types check the datasheet.
or you can put a 5volt regulator like 7805 by placing one or two diodes on the ground pin. The amount is based on the voltage drop of the diode. This would work for all tubes, I attached mine to the case as a heat sink.
that sounds complex...do you think it is really worth it?
i am also thinking of adding a charge pump which would bring the voltage at 12v...so i follow the same schem with 12v...how about that?
I am using 30volts, but I am using a 30vdc wall wart I got at good will for $2. I use a 12volt regulator on the heater, a 7812. Its simple power in, ground power out.. Just need to attach it to the cast to get rid of heat. In mine I use the LM317 with 100ohm resister for R1 and 800ohm for R2. This way I can go all the way to 52 volts on the pedal, with no changes.
But in your case, If you want to go to 18 the single regulator is fine. you have to remember that the heaters pull 150ma alone. If you use a step up then you have to double that or more, so a voltage doubler you need at least 300ma to run your 150 ma heaters in series and .6 amps to run in parallel.
With this design the tube heaters are the most important to get right. 9 volts will work, just will in time kill the tube faster.
(http://www.reconnsworld.com/power/12vpowersupply.gif)
Remember that everything up to input I on the regulator is in the wall wart. You would also send point I to the rest of your design. The LM7812 is good up to 35volts I believe.
in case some one wants to build this, it would not be 18volts after rectification. you have to multiply by 1.414 = ~25volts
i wanna power all my pedals with one power supply...this is why i am thinking about the voltage multiplier with a max1044!with a 12v regulator probably!
Quote from: tasos on May 04, 2011, 08:15:15 AM
i wanna power all my pedals with one power supply...this is why i am thinking about the voltage multiplier with a max1044!with a 12v regulator probably!
Just be sure to check the current requirements of the MAX chip. I believe it is down in the low mA when powered by 9V. It may run 1..... possibly 2 pedals but, I doubt it will provide enough current for more than that.
Good Luck ;D
Quote from: Govmnt_Lacky on May 04, 2011, 08:18:03 AM
Quote from: tasos on May 04, 2011, 08:15:15 AM
i wanna power all my pedals with one power supply...this is why i am thinking about the voltage multiplier with a max1044!with a 12v regulator probably!
Just be sure to check the current requirements of the MAX chip. I believe it is down in the low mA when powered by 9V. It may run 1..... possibly 2 pedals but, I doubt it will provide enough current for more than that.
Good Luck ;D
When powering multiple pedals it is better to start @ a higher voltage and divide or regulate down then to go up.
for instance, your tube draws 150 MA for heaters, if you up the voltage to 18 and then back down you would need at least 300MA for the same work. Since each part in between will have loss you maybe looking 600MA.
While if you create a ~25volt regulator and go down, you could feed 25v to the system and a 12volt regulator to each tube heater, or even 12volt regulator to each pedal as most 9volt pedals will run on 12 with no problem.
Quote from: Govmnt_Lacky on May 04, 2011, 08:18:03 AM
Quote from: tasos on May 04, 2011, 08:15:15 AM
i wanna power all my pedals with one power supply...this is why i am thinking about the voltage multiplier with a max1044!with a 12v regulator probably!
Just be sure to check the current requirements of the MAX chip. I believe it is down in the low mA when powered by 9V. It may run 1..... possibly 2 pedals but, I doubt it will provide enough current for more than that.
Good Luck ;D
i am thinking of putting the max1044 inside the box so it will only run one pedal!the tube drive!
guys i have read that this pedal at 9v doesn't sound really great...
what do you think?does it really worth it using a charge pump etc etc?
if you build this pedal right it sounds good at 9 volts but only with a 12au7 tube. I have never run across cothode stripping in a tube at 9 volts by the way. I am sure it can happen but it hasnt yet and I gigged a triple caster really hard for over a year. 12 volts is nice and the higher you go the better they sound. at about 100 volts and up they sound really good but there are many other designs that sound better. I run one at 9 volts and another at 45 as they sound great both ways for different things. its not really a distortion pedal. it just adds a little drive on top of whatever you got going already. I use them to "warm up" solid state amps and they do it well. They also fatten up a single coil guitar nicley. For what its worth. Oh yeah and when i run higher voltage i run 9 volts from the dc jack to pin 5 and ground pin 4. 9 is un connected. i run a seperate wire to my voltage multiplier smps or whatever voodoo i am using. Be careful though. and make sure your parts are rated for the higher voltage. ;) this stuff can kill you :icon_eek: Cheers, Greg
Quote from: zambo on May 05, 2011, 12:01:10 AM
if you build this pedal right it sounds good at 9 volts but only with a 12au7 tube. I have never run across cothode stripping in a tube at 9 volts by the way. I am sure it can happen but it hasnt yet and I gigged a triple caster really hard for over a year. 12 volts is nice and the higher you go the better they sound. at about 100 volts and up they sound really good but there are many other designs that sound better. I run one at 9 volts and another at 45 as they sound great both ways for different things. its not really a distortion pedal. it just adds a little drive on top of whatever you got going already. I use them to "warm up" solid state amps and they do it well. They also fatten up a single coil guitar nicley. For what its worth. Oh yeah and when i run higher voltage i run 9 volts from the dc jack to pin 5 and ground pin 4. 9 is un connected. i run a seperate wire to my voltage multiplier smps or whatever voodoo i am using. Be careful though. and make sure your parts are rated for the higher voltage. ;) this stuff can kill you :icon_eek: Cheers, Greg
Zambo makes good points, who's experience is worth more than theory.
I believe he is not seeing cathode striping because of the low voltage on the plates http://www.diyaudio.com/forums/tubes-valves/79405-doubts-cathode-stripping-tubes.html (http://www.diyaudio.com/forums/tubes-valves/79405-doubts-cathode-stripping-tubes.html), and well made tubes, some tubes may not fair as well. The 12AU7 and the 12U7 are really the same tube, with the 12U7 having more gain, but meant to run at 12Volts. IF you pull an old 12AU7 datasheet, it and the 12U7 match up. In the 12U7 datasheet they say 10volts min for the heaters. They mention shorter tube life. But has 12U7 is cheep and they mean 1000's of hours of still uses-full life, which even on tour is more than a year.
here is more information on heaters http://www.freewebs.com/valvewizard/heater.html
also @ zambo have you tried a Toroidal Power transformer? from 12V ac to upto 240Vdc?
http://www.hoffmanamps.com/MyStore/perlshop.cgi?action=template&thispage=Transformers&ORDER_ID=274142820
I am thinking of using one with a compactron 6AF11 amp I am building. I could pull my 12 volts off the 12V ac transformer and then the rest at 240V
thanks guys...can 18v kill me? ???
i will get back when i get my tube...i have read that the 12ax7 has more gain...do you think this would work nicely using the same schematic[i know the two tubes have different pinout] with 18v and 9v on the heaters?
I have not had luck even @ 30 volts making a 12AX7 sound good in this design.
as for voltage, AMP's kill not voltage. so under the right situation 1 volt can kill you. But I would not worry to much. You should practice safe habits, don't touch the electronics while on with two hands. have non conducting shoes. ect...
Why I think the 12AX7 sounds bad in this design
1) the plate and cathode values are created for a very steep load line for a 12AU7 changing the design may help,
2) the 12AU7 was make to run in low voltage designs, with the 12u7 as the tested version, but also high voltage designed with out a isolation transformer, unlike say the 12K5
ok!no 12ax7 for me! ;D
i will do as i said...max1044 voltage doubler...as for the heaters would 12v or 9v would be better?[9v from dc jack or 18v from max1044 and then 12v regulator?]
Quote from: tasos on May 05, 2011, 11:25:02 AM
as for the heaters would 12v or 9v would be better?[9v from dc jack or 18v from max1044 and then 12v regulator?]
Strictly you can have 12V heaters (18V regulated down to 12V) or 6V heaters (9V regulated down to 6V).
If you run the 12V heaters at only 9V gain may be lower, but it will work. I would suggest running at a 'proper' voltage (6V or 12V), since you can always reduce it later.
No, 18V cannot kill you. You won't even feel anything until above 60V.
yeah sorry about the scare there....18 volts is no big but i have seen a lot of guys get crazy from this project and jump up to over 150 volt projects, which gets a bit more freaky. @ icarros - I have not tried a toroidal yet but would like to. I have been building amps full scale latley to kind of get my theory and building skills up to par ( results are debatable lol) so i havent messed with anything under 250 volts for a while now. I am about to start building small stuff again as its where i really have fun. Doing the 2 x 12au7 push pull parallel amp again with a high gain preamp running a smps. Got to see if i can get it sounding good....results when i get it going again!
Quote from: zambo on May 05, 2011, 07:53:52 PM
yeah sorry about the scare there....18 volts is no big but i have seen a lot of guys get crazy from this project and jump up to over 150 volt projects, which gets a bit more freaky. @ icarros - I have not tried a toroidal yet but would like to. I have been building amps full scale latley to kind of get my theory and building skills up to par ( results are debatable lol) so i havent messed with anything under 250 volts for a while now. I am about to start building small stuff again as its where i really have fun. Doing the 2 x 12au7 push pull parallel amp again with a high gain preamp running a smps. Got to see if i can get it sounding good....results when i get it going again!
Thanks Zambo
I am looking at using one for a compactron amp design. I got some 6AF11 off ebay. The have Twin Triode - Sharp-Cutoff Pentode. I see a higher fain 2 watt champ coming together.
But I have been working with 12volt tubes made for car radios, skip the first min, as the tubes warm up. This is a single 12u7 and 2 12K5 with a valve-caster, Its still in design lend your opinions
I know this isn't what most peeps want, but what would be the best way to get the CLEANEST boost from the Valvecaster ?? I'm hoping to use this as a preamp.
Quote from: 1878 on May 06, 2011, 07:31:00 PM
I know this isn't what most peeps want, but what would be the best way to get the CLEANEST boost from the Valvecaster ?? I'm hoping to use this as a preamp.
Since the Gain pot is setting the BIAS of the tube @ 50K it is almost clean.
I would put a 100 or 250 k pot and twist until you like it. Then measure what it is and use the closest resistor value. Same with the second cathode (pin 8), Also some cathode bypass caps may help, a .1uf is a good start, but they can adjust tone
a really good change would be to put a 50K on the cathode with a 6.8uf cap with a 1meg pot connect to the cap. So the cap and pot is in parallel with the 50K. This would be a brightness gain
Thanks very much :)
@ Iccaros- Nive man! All that is running off of 12 volts? Sweet! I love little amps! I am starting a new thread for one today. 2 x 12au7 amp running on 9volt adaptor .
@ 1878 - more voltage ( 18 volts or more) and smaller anode/plate resistors is a good start as well. I like the cathode biased at typical 1.5 k and 2.8 k values but the adjustable pot is cool too. Voltage = volume and volume = headroom in general. I am not the sharpest tool in the shed but this has been my experience so far. Smart guys feel free to chime in anytime!
Quote from: zambo on May 08, 2011, 02:48:07 PM
@ Iccaros- Nive man! All that is running off of 12 volts? Sweet! I love little amps! I am starting a new thread for one today. 2 x 12au7 amp running on 9volt adaptor .
i want the link! :icon_twisted:
at your service! http://www.diystompboxes.com/smfforum/index.php?topic=91500.0 :icon_smile:
I'm having trouble with my build... It's an independent pentode boost and valvecaster in one enclosure.
I've got a separate voltage regulator circuit on vero that I'm trying to use to distribute the different voltage requirements throughout the build.
So, I'm using a 7812 and an LM317 to do this... I know something is wrong, as they get hot very quick and don't produce much voltage at all.
I have it built on my breadboard, and it seems to be working fine. I've cataloged some multimeter readings in hopes of finding the culprit.
The following are the values I've found on my breadboard, with values taken directly from the pedal in bold:
voltages (12v 800ma wall wart)
7812
pin 1: 16.1v 5.11v
pin 2: 0v .03v
pin 3: 11.55v 2.52v
317
pin 1: .02v .02v
pin 2: 1.12v .02v
pin 3: 11.55v 2.5v
Continuity to ground (no voltage in)
7812
pin 1: 1 1
pin 2: ~0 ~0
pin 3: ~1241 ~978
317
pin 1: ~0 ~0
pin 2: ~215 ~0
pin 3: ~1241 ~980
with voltage
7812
pin 1: 1 1
pin 2: ~0 ~0
pin 3: 1 1
317
pin 1: ~0 ~0
pin 2: ~1800 ~0
pin 3: ~1244 1
Obviously, with the input voltage being so low, the 7812 and 317 aren't going to function right, but the v reading straight from the dc jack on the pedal reads about 5.1v... Should this suggest that the problem is before the regulator circuit? Does anyone have any idea where to start troubleshooting this?
Quote from: Ratbones on May 08, 2011, 09:40:00 PM
I'm having trouble with my build... It's an independent pentode boost and valvecaster in one enclosure.
I've got a separate voltage regulator circuit on vero that I'm trying to use to distribute the different voltage requirements throughout the build.
So, I'm using a 7812 and an LM317 to do this... I know something is wrong, as they get hot very quick and don't produce much voltage at all.
I have it built on my breadboard, and it seems to be working fine. I've cataloged some multimeter readings in hopes of finding the culprit.
The following are the values I've found on my breadboard, with values taken directly from the pedal in bold:
voltages (12v 800ma wall wart)
7812
pin 1: 16.1v 5.11v
pin 2: 0v .03v
pin 3: 11.55v 2.52v
317
pin 1: .02v .02v
pin 2: 1.12v .02v
pin 3: 11.55v 2.5v
Continuity to ground (no voltage in)
7812
pin 1: 1 1
pin 2: ~0 ~0
pin 3: ~1241 ~978
317
pin 1: ~0 ~0
pin 2: ~215 ~0
pin 3: ~1241 ~980
with voltage
7812
pin 1: 1 1
pin 2: ~0 ~0
pin 3: 1 1
317
pin 1: ~0 ~0
pin 2: ~1800 ~0
pin 3: ~1244 1
Obviously, with the input voltage being so low, the 7812 and 317 aren't going to function right, but the v reading straight from the dc jack on the pedal reads about 5.1v... Should this suggest that the problem is before the regulator circuit? Does anyone have any idea where to start troubleshooting this?
Each need at least 2 volts to operate, you do know they have different pin outs right? These voltages look like mine when I wired a lm317 like a 7812.
can you draw out how they are connected.
(http://circuits.datasheetdir.com/39/LM7812-pinout.jpg)
using this pinout 16volts to pin 1, ground on pin 2 and vout on pin 3. should be 16, 0, 12.
for the 317 (http://upload.wikimedia.org/wikipedia/commons/thumb/e/e7/Lm317_front.png/220px-Lm317_front.png)
pin 1 is your adjustment, so you should have a 100 - 250 ohm resister from here to pin 2 and a 5k pot to ground.
Pin 2 is your Vcc or Vout
Pin 3 is voltage in.
I would pull each connection and only connect one regulator at a time, no tubes in. Remember the heat sink is Vout also so do not have it touch the case or ground.
Oh, goodness, the heatsink is vout!?!? That's an awfully silly thing for me to have overlooked... because I have both to-220 cases bolted directly to the enclosure, which is grounded... So if I want to utilize the enclosure for heat wicking, I need to electrically isolate both regulators with something that conducts heat, but not electricity huh?
Quote from: Ratbones on May 09, 2011, 11:47:54 AM
Oh, goodness, the heatsink is vout!?!? That's an awfully silly thing for me to have overlooked... because I have both to-220 cases bolted directly to the enclosure, which is grounded... So if I want to utilize the enclosure for heat wicking, I need to electrically isolate both regulators with something that conducts heat, but not electricity huh?
there are special rubber isolators...they look like this
http://t1.gstatic.com/images?q=tbn:ANd9GcR4SNS7n72GOSzHbt4VfeHfHPHCnmO30j80SprA-XnZ5al0vxVf&t=1 (http://t1.gstatic.com/images?q=tbn:ANd9GcR4SNS7n72GOSzHbt4VfeHfHPHCnmO30j80SprA-XnZ5al0vxVf&t=1)
Thanks for the advice!
Just now pulled the screws bolting the regs to the enclosure and slipped a piece of paper between the regulators and aluminum wall...
Hot damn! The thing works!!! And it sings!!! With the pentode boost driving the 12au7 this thing is monstrous!
Quote from: Ratbones on May 09, 2011, 12:29:58 PM
Thanks for the advice!
Just now pulled the screws bolting the regs to the enclosure and slipped a piece of paper between the regulators and aluminum wall...
Hot damn! The thing works!!! And it sings!!! With the pentode boost driving the 12au7 this thing is monstrous!
so you have a schamatic for the pentode boost? I am looking at some 5902 submini pentodes. I am most intrested on how you did loading between the pentode and the 12au7 or is its grid resistance good enough.
I actually just used Frequency Central's awesome super simple submini pentode boost here: http://www.diystompboxes.com/smfforum/index.php?topic=70524.0 (http://www.diystompboxes.com/smfforum/index.php?topic=70524.0)
And as far as loading, I'm not sure I follow... This is my first build with tubes, and I'd love to learn more, so let me know if there is a better approach than this!
Here's a diagram:
Guitar input --> true bypass switchable pentaboost --> true bypass switchable valvecaster --> guitar out
So the way I've done it was just what seemed to be a simple way of having either, both or neither engaged at once.
Is there a better way?
Quote from: Ratbones on May 10, 2011, 12:22:12 AM
I actually just used Frequency Central's awesome super simple submini pentode boost here: http://www.diystompboxes.com/smfforum/index.php?topic=70524.0 (http://www.diystompboxes.com/smfforum/index.php?topic=70524.0)
And as far as loading, I'm not sure I follow... This is my first build with tubes, and I'd love to learn more, so let me know if there is a better approach than this!
Here's a diagram:
Guitar input --> true bypass switchable pentaboost --> true bypass switchable valvecaster --> guitar out
So the way I've done it was just what seemed to be a simple way of having either, both or neither engaged at once.
Is there a better way?
That tube wants 20K for load resistance, which means you get less power out as you are not drawing current to spec.. The volume pot should act as the load, but I think these should be 1meg not 100K, but I am willing to hear other thoughts on this. It seams that 100K is sensitive to what else comes after it.
But I don't think at these voltages you are going to hurt it, but I am interested in other thoughts.
I just "Won" (14) 5902 submini pentodes. They have a rating of 1 watt clean and 4 watts dirty. I was going to try and make a AX84 HO with them and some 6111's I have... but this could be a good project for one of them.
To my ears it sounds quite nice, but if the load being under spec is harmful to the life span of the tube, then I wonder if I should look into balancing the load out...
Quote from: Ratbones on May 10, 2011, 11:43:06 AM
To my ears it sounds quite nice, but if the load being under spec is harmful to the life span of the tube, then I wonder if I should look into balancing the load out...
Since the tube is running in a starvation mode, I don't think it matters. But Its a question I ask even with the 12AU7, it want around 6K and the design has a 100K pot.
I don't know where to but led, 9v adapter and how to connect 9v battery socket and 9v plug.
I have 2 way tumbler with 2 legs and 3 way tumbler with 3 legs.
Another problem is that I wanna but tub inside metal box for safe.
I don't know how to do it.
also you want but write english.
you don't know how to do it
;D
ah ok but is put - now makes sense...
how are you going to use this pedal? If you are going to switch it on and off while playing then you need to use at least a dpdt stompswitch. For an led you should probably use a 3pdt switch. the wiring diagrams are on this thread for that multiple times. just do a quick search and you will find it. To mount the tube inside, use a pcb mount tube socket on perf board and a ribbed box ( for your pleasure ) and moun the board in the box. Or you can take an L bracket or bent sheet matal, drill a big enough hole in it to mount a normal tube socket and mout the bracket to the inside of the box. Renegadrian has the easiest vero board layouts to follow and they work well consistently if you follow them. Good luck and post results!
Quote from: Death Super Mario on May 12, 2011, 02:33:32 PM
I don't know where to but led, 9v adapter and how to connect 9v battery socket and 9v plug.
I have 2 way tumbler with 2 legs and 3 way tumbler with 3 legs.
Another problem is that I wanna but tub inside metal box for safe.
I don't know how to do it.
Once the heaters are on, this tube gets warm so if you want it in the box, drill air holes or give it some space. The heaters dissipate almost 2watts of heat..
Hey guys, I've got a successful (mostly) well operating build now... It's a valvecaster w/ a switchable 5672 submini preamp.
First of all, it's kind of noisy... 60Hz hum, you know. Probably the wall wart I'm using is unregulated. That's not really the weird thing; what IS weird is that when I run that unregulated 12v 800ma wall wart thru a simple rc filter in a little box I made a while ago, the valvecaster/preamp fails to operate AT ALL. Measuring voltage straight from the wall wart I get somewhere around 16v. Measured from the jack on the little rc circuit, it's about the same... measured immediately from the dc jack on the valvecaster, I've got really low, like 3v low, voltage... What could be up with that!? The V.C. works fine straight from the wall wart. Is the RC circuit consuming so much amperage that the voltage drops that much?
Quote from: Ratbones on May 13, 2011, 11:43:30 AM
Is the RC circuit consuming so much amperage that the voltage drops that much?
That depends.... is there a TO-92 voltage regulator in your RC circuit?
If so, then you should consider swapping it out for the TO-220 series that is rated (usually) at 1A. The TO-92 series regulators are only rated (usually) to 100mA.
Thanks for the advice Gov. Lackey, but after a bit more experimentation, I seem to have figured out the source of my frustrations! First off, something in my house's mains at that outlet gets buzzy every now and then apparently... So most of the noise was due to that.
But! Most importantly... I retraced my schematic to see if I had done something wrong with the submini... turns out that I had decided to connect the b+ connections straight to the + dc so that my wall wart's 16v of preregulated would go to providing more clean headroom. So, on a hunch, I cut that connection and tapped the b+ connection of the 5672 circuit to the output of the 7812, and voila. No more noise. At all.
Turns out, at least in my experience, that b+ regulation via a 7812 or LM317 does go toward filtering out noise. Thought that might be useful to someone else in the future :)
Quote from: Ratbones on May 13, 2011, 01:08:28 PM
Thanks for the advice Gov. Lackey, but after a bit more experimentation, I seem to have figured out the source of my frustrations! First off, something in my house's mains at that outlet gets buzzy every now and then apparently... So most of the noise was due to that.
But! Most importantly... I retraced my schematic to see if I had done something wrong with the submini... turns out that I had decided to connect the b+ connections straight to the + dc so that my wall wart's 16v of preregulated would go to providing more clean headroom. So, on a hunch, I cut that connection and tapped the b+ connection of the 5672 circuit to the output of the 7812, and voila. No more noise. At all.
Turns out, at least in my experience, that b+ regulation via a 7812 or LM317 does go toward filtering out noise. Thought that might be useful to someone else in the future :)
the 7812 and LM317 are rated for 80db of ripple rejection, but I would not rely on that.
For what it's worth, that suppression made a huge difference in my pedal. It's pretty much noise free now, where as before it was almost unusable because of that noise. I'm sure with a decent, well regulated wall wart it probably doesn't matter at all, but mine was a dollar from good will, and it sounds like it haha
Quote from: Ratbones on May 13, 2011, 03:40:33 PM
For what it's worth, that suppression made a huge difference in my pedal. It's pretty much noise free now, where as before it was almost unusable because of that noise. I'm sure with a decent, well regulated wall wart it probably doesn't matter at all, but mine was a dollar from good will, and it sounds like it haha
I under stand, I have a well regulated power strip from APC... So all of my pedals and amp are quite..
Plus I get all my wall warts from Good will now.. Using a Compaq Laptop 24V for my current project.
I soldered my valvecaster. I used beavisaudio less wiring diagram.
http://imageshack.us/photo/my-images/18/valvecaster.jpg/
I have to solder 9v battery and 9v adapter plug. My be led too.
I need to work on metal box. I thinking to isolate the box with electrical tape.
Quote from: Death Super Mario on May 15, 2011, 04:06:16 AM
I soldered my valvecaster. I used beavisaudio less wiring diagram.
http://imageshack.us/photo/my-images/18/valvecaster.jpg/
I have to solder 9v battery and 9v adapter plug. My be led too.
I need to work on metal box. I thinking to isolate the box with electrical tape.
No need to Isolate.. The metal Box is your ground....
Metal is good electricity leader.
I had small PCB board guitar effect. One corner contacted with metal box
and it melted some parts on board.
I wanna put tube inside the metal box.
To I need to cover soldering points ?
Is electrical tape good for covering ?
I only have simple soldering iron with plug.
Quote from: Death Super Mario on May 15, 2011, 06:27:50 AM
Metal is good electricity leader.
I had small PCB board guitar effect. One corner contacted with metal box
and it melted some parts on board.
I wanna put tube inside the metal box.
To I need to cover soldering points ?
Is electrical tape good for covering ?
I only have simple soldering iron with plug.
For this project, if you are using a PCB and not direct to the sockets...
Then Heat Shrink on all wires (use anyways)
Heavy construction paper (so it does not rip) attached to the bottom. So you have your post, cut a piece of paper the same size as the board, place board over post, then put in screws...
With heat electrical tape will come off. Paper burns @ high temperatures, well if your pedal got hot enough to set paper on fire, your guitar cord would have already started to melted.
I soldered directly to the socket.
http://imageshack.us/photo/my-images/18/valvecaster.jpg/
at 9 to 12 volts these tubes dont get that hot. I put one inside a box with minimal venting and it was fine. Just stop it from shorting out. I mount the tube socket to an L bracket and mount the bracket to the box. Its pretty easy. I actualy put 3 tubes together in one box that way. No problems.
Quote from: Death Super Mario on May 15, 2011, 01:43:57 PM
I soldered directly to the socket.
http://imageshack.us/photo/my-images/18/valvecaster.jpg/
You could use heat shrink, you can get large diameter at a Auto Repair place. I have some that will go around a 8 pin Octal, so it would easily cover everything..
while 12AU7 and 12AX7 do not get hot, others do, Well my 12AU7 got really hot, but I learned after wards that my LM7812 went bad and I was putting 30 volts on the heater
Quote from: iccaros on May 15, 2011, 04:31:11 PM
Quote from: Death Super Mario on May 15, 2011, 01:43:57 PM
I soldered directly to the socket.
http://imageshack.us/photo/my-images/18/valvecaster.jpg/
You could use heat shrink, you can get large diameter at a Auto Repair place. I have some that will go around a 8 pin Octal, so it would easily cover everything..
while 12AU7 and 12AX7 do not get hot, others do, Well my 12AU7 got really hot, but I learned after wards that my LM7812 went bad and I was putting 30 volts on the heater
I have seen that some hot air blower similar to the soldering iron are used for shrinking heat shrink tightly onto. Can i use hairdryer ?
you can use a lighter if you want. it just reacts to heat, doesnt matter what kind. I use a lighter all the time. I dont know if a hair dryer gets hot enough. never tried it.
I use a heat gun, made for removing paint. I have used hair dryers. Lighter.... I burn things so I stopped.. ) ..my dogs morning breath... what ever, just heat
lol...morning breath, I got to go breath on some and see if it works... :icon_twisted:
Hey,
I have custom tube protectors for this project
http://www.diystompboxes.com/smfforum/index.php?topic=91656.0
(http://i852.photobucket.com/albums/ab86/pigyboy_2009/la_rosa2_small.jpg)
I just finished this thread and I am really only left with one question before I begin.
If I build my pedal with a 78XX regulator in it, will I not be able to use a regulated power supply with it? Like, if I let a friend borrow it and he puts it in his pedal board he won't be able to use his regulated power supply. He'll have to use my wall wart. Correct? This is because there will be some voltage drop from the second regulator. Am I thinking right?
This was discussed briefly in passing earlier in the thread and I never saw it mentioned again.
Thanks!
@Bill
That depends, what is the regulated voltage from his supply. All pedals list a voltage on them, and all have a min requirement. It would be the same with using a resistor.. I am assuming that you are talking heaters..
So say you have 18 volts and you want to drop to 12, so 18 - 12 = 6. A 12au7 pulls .150 ma so 6/.150 = 40 ohms.. 6*.150 = .9 watts (right math people :) ) so you would need a 1 watt min resistor (2 for safety)
but if you plugged this into a 12 volt supply this would no longer work as you would only get ~ 6 volts to the tube.
So The issues is not the regulator, but Ohms Law.. So if you plan on changing power you need to plan for this..
If your source will not exceed 35 volts a LM78XX is the best choice, as you can go from 14.5 - 35 volts with no real issues.. but if you do not have min of 14 volts you may have issues.
This is true of every pedal on the market. Most are designed to go on a peddle board in the first place, so they use voltage pumps or something like that if they need higher voltage than say 12v... my regulated supply goes to 48v, but that is for phantom power..
Okay, I built this beast on a breadboard using Renegadrian's 'No Tone' vero and it works great and sounds great, but it does some weird things to my power supply!
I have a 9V 300ma Boss adapter, a 12V 400ma random (noisy as hell) adapter and an 18V 6.5A Laptop adapter that I've tried. I run it into a Beavis style I/O box with the V-Sag knob...
When I have the adapters on full (V-Sag maxed) all the voltages are slightly lower than usual, and any tweaking of the knob makes the Voltage jump all over the place (I have a Voltmeter inline), no smoothness to it. It's a real pain trying to use the 18V and dial it down to 12.6V...pretty well impossible. The 12V adapter usually runs at ~12.6V for other circuits, but with the Valvecaster it feeds 11.6V max, and the 9V feeds 9.x but drops to 8.7V with the Valvecaster circuitry.
I tried a couple filter circuits, one being the Beavis Huminator, but the Valvecaster refuses to work with the filtered 12V from that circuit...will only work with the raw power fed into it.
Is this a normal thing for the Valvecaster to create so much havok on the power side? I may order some more parts to build a charge pump/regulator into the pedal, but I'd prefer to keep the cost to a minimum. Anybody have this happen to them? Does this even make sense??
Quote from: CheopisIV on May 17, 2011, 12:56:00 AM
Okay, I built this beast on a breadboard using Renegadrian's 'No Tone' vero and it works great and sounds great, but it does some weird things to my power supply!
I have a 9V 300ma Boss adapter, a 12V 400ma random (noisy as hell) adapter and an 18V 6.5A Laptop adapter that I've tried. I run it into a Beavis style I/O box with the V-Sag knob...
When I have the adapters on full (V-Sag maxed) all the voltages are slightly lower than usual, and any tweaking of the knob makes the Voltage jump all over the place (I have a Voltmeter inline), no smoothness to it. It's a real pain trying to use the 18V and dial it down to 12.6V...pretty well impossible. The 12V adapter usually runs at ~12.6V for other circuits, but with the Valvecaster it feeds 11.6V max, and the 9V feeds 9.x but drops to 8.7V with the Valvecaster circuitry.
I tried a couple filter circuits, one being the Beavis Huminator, but the Valvecaster refuses to work with the filtered 12V from that circuit...will only work with the raw power fed into it.
Is this a normal thing for the Valvecaster to create so much havok on the power side? I may order some more parts to build a charge pump/regulator into the pedal, but I'd prefer to keep the cost to a minimum. Anybody have this happen to them? Does this even make sense??
Voltmeter in line? you are measuring from ground to something right.. you only have voltage if you have resistance.. so I am not sure what in line is.. That is how you measure current..
so what are your voltages on the pins?
The heaters draw 150ma and the rest well 1 ma I believe (12/100K is around .1 ma right.. so if your wall warts can not really put out the 500ma, then it will drop voltage on load (other things draw current also so you have to take that in to account)
you only need the heaters @ 12 or really 12.6 but 12 is good..
so drop 6 volts at .150 ma..
a 2 watt resistor on your heaters @ (6 /.15 = ) 40ohms at ( .15*6 = ) .9 watts of dissipation.. so 1 watt is good, 2 better.
Thanks for the reply; my Voltmeter is one of these
(http://cdn1.iofferphoto.com/img/item/673/696/51/rr9xYwAFsbpnK0Q.jpg)
Has two rear terminals, V+ and ground and sits between my I/O box and breadboard. It works smoothly with my voltage sag knob on all other circuits but the Valvecaster. Even the 18V 6.5A adapter acts goofy when the Valvecaster is boarded, but it shouldn't even notice the circuit with that much amperage available. I can't dial it down to 12V, so I've only used the 12V (screechy) and the Boss 9V so I don't cook anything. Here are my reads;
9V (9.6 on all other circuits, 8.46 on the Valvecaster)
1) 3.58
2) -0.07
3) 0.02
4) 0.03
5) 8.44
6) 5.08
7) -0.04
8.) 0.02
9) 4.21
12V (12.6 all others, 11.68 on Valvecaster)
1) 3.12
2) -0.34
3) 0.01
4) 0.03
5) 11.64
6) 4.75
7) -0.28
8.) 0.02
9) 5.79
The Raw Voltage is measured at the output from the I/O box. I wonder if I'm getting some inductance in my wiring with all the little voltage readings I'm getting on the pins where everyone is reading 0? If I pull the tube, everything works normally again, the V-sag knob drop is linear and controlled, put the tube back in and it's chaos to adjust. I have tried several tubes, all the same results.
This is my valvecaster soldering.
(http://imageshack.us/m/30/1115/valvecaster.jpg)
It's the thread that never ends!
Anyhow, I've made a couple more valvecasters of late so I thought I should probably post them up.
First up is the 'Philcaster'. Named because it was built for Phil... Who really, really needs to find it (he's managed to lose it!). It's essentially a switchable twincaster with a few tweaks.
Run in a single valve it can be a clean boost or distortion. With two it's just got massively more gain. It also has a bright switch which when enabled can cut out some of the inherent bassiness of the pedal when used with humbuckers. Also of note is that this pedal really sounds best when used after a pedal with a buffer in it in the chain.
It's running a Madbean Road Rage charge pump (the only bit of silicon in the pedal), running the plates at 24v, heaters are running 12v. The valves are NOS RFT ECC82. Unlike the ones I've done running 12DW8's, these don't require anywhere near the current and sound better too.
(http://juansolo.demon.co.uk/stompage/images/philcaster-o1.jpg)
(http://juansolo.demon.co.uk/stompage/images/philcaster-o2.jpg)
(http://juansolo.demon.co.uk/stompage/images/philcaster-i.jpg)
After building the Philcaster, it turned out so good that I decided to re-visit one of my old valve pedals. So this is essentially an old pedal re-used and re-finished.
I've gone for a single valve pedal as I still have my old Twincaster for double valve excess. This has more grunt than the PC does in single tube mode so it doesn't really clean up as well as the PC does.
So what's different? Well quite a few of the values are for a start to make this more simple than the much more tweakable PC. All the components are mounted directly to the socket to minimise noise from cables going backwards and forwards to the boards as with previous versions. The gain no-longer adjusts the bias of the valve, instead working between stages. Theres a buffer on the output and theres Madbean's Road Rage providing 15v to that, 23v to the plates and 12v to the heaters. It can take a variety of valves, but out of what we had, the NOS Brimar 12BH7 sounded best.
The results are stonking. This is the quietest valve pedal we've made so far and it pushes my new 6V6 MJW 5 watt amp (very clean) into pure AC/DC overdrive. It sounds glorious.
(http://juansolo.demon.co.uk/stompage/images/boobtube-o.jpg)
(http://juansolo.demon.co.uk/stompage/images/boobtube-i.jpg)
Quote from: CheopisIV on May 17, 2011, 02:58:04 AM
Thanks for the reply; my Voltmeter is one of these
(http://cdn1.iofferphoto.com/img/item/673/696/51/rr9xYwAFsbpnK0Q.jpg)
Has two rear terminals, V+ and ground and sits between my I/O box and breadboard. It works smoothly with my voltage sag knob on all other circuits but the Valvecaster. Even the 18V 6.5A adapter acts goofy when the Valvecaster is boarded, but it shouldn't even notice the circuit with that much amperage available. I can't dial it down to 12V, so I've only used the 12V (screechy) and the Boss 9V so I don't cook anything. Here are my reads;
9V (9.6 on all other circuits, 8.46 on the Valvecaster)
1) 3.58
2) -0.07
3) 0.02
4) 0.03
5) 8.44
6) 5.08
7) -0.04
8.) 0.02
9) 4.21
12V (12.6 all others, 11.68 on Valvecaster)
1) 3.12
2) -0.34
3) 0.01
4) 0.03
5) 11.64
6) 4.75
7) -0.28
8.) 0.02
9) 5.79
The Raw Voltage is measured at the output from the I/O box. I wonder if I'm getting some inductance in my wiring with all the little voltage readings I'm getting on the pins where everyone is reading 0? If I pull the tube, everything works normally again, the V-sag knob drop is linear and controlled, put the tube back in and it's chaos to adjust. I have tried several tubes, all the same results.
Sorry I must be stupid.. when you connect your voltmeter (your pannal VU )you plug one side into your i/o box and then have no cable, but the other probe is connected to the valve caster?
if so you not measuring volatge, as voltage can only be measured over a load. http://physics-tutor.site90.net/drupal/node/29 (http://physics-tutor.site90.net/drupal/node/29), that would be measuring current, which If I remember my EE coursed from 20 years ago, a VU will read amp or milliamp in this configuration.
as for voltages, if these are read from pin to ground with tube in, well they are low for the plates.. I would expect 7 volts or so, are you running this through a voltage regulator, and why are you running it off a SAG power supply, the last thing we want in a starved plate design is low battery simulate, which is what your sag is doing. .That is cool on some old effects pedals, but kills head room on this pedal.
as for
@juansolo
Good work
I was going to change the gain to a 10uf attached to a 50 - 100K pot. With a 50K (47K) to ground
what did you use for the art? I am thinking of using the tee shirt iron on stuff..
also where are people getting those chrome washers for the tube protectors.. I have been to several hardware stores and can not find any large enough.
I get asked about the decals a lot so did a how to page (http://juansolo.demon.co.uk/stompage/decaling.html).
Tube protectors came from a blokey in HK on ebay IIRC.
Quote from: iccaros on May 17, 2011, 04:39:38 PM
Sorry I must be stupid.. when you connect your voltmeter (your pannal VU )you plug one side into your i/o box and then have no cable, but the other probe is connected to the valve caster?
if so you not measuring volatge, as voltage can only be measured over a load. http://physics-tutor.site90.net/drupal/node/29 (http://physics-tutor.site90.net/drupal/node/29), that would be measuring current, which If I remember my EE coursed from 20 years ago, a VU will read amp or milliamp in this configuration.
as for voltages, if these are read from pin to ground with tube in, well they are low for the plates.. I would expect 7 volts or so, are you running this through a voltage regulator, and why are you running it off a SAG power supply, the last thing we want in a starved plate design is low battery simulate, which is what your sag is doing. .That is cool on some old effects pedals, but kills head room on this pedal.
Lol, no, i doubt you're stupid. I think i just described it wrong! It sits in parallel between my I/O box and the breadboard, There are two wires into it (V+ and Ground) and two wires out of it to my breadboard (V+ and ground). The purpose of the 'sag' knob is to dial my 18V adapter down to 12V (or 9V, etc), not to starve the Valvecaster. It works perfectly on any other circuit, but the Valvecaster acts funny.
An interesting thing happened and I think (hope) it's the issue. I was checking to make sure none of my components were touching each other and when I wiggled the input cap, i heard a scraping noise.... This breadboard has a metal plate on the bottom and is supposed to have a shield between it and the board, so I shouldn't have heard the scraping sound. I think I have to rip it down and check my board... I'm thinking there may be something grounding out under there. As soon as I get the time, I'll have to rebuild. Thanks everyone for the comments and tips.
Beautiful pedal a few posts up too! I love seeing other people's creations!
Quote from: juansolo on May 17, 2011, 05:10:01 PM
I get asked about the decals a lot so did a how to page (http://juansolo.demon.co.uk/stompage/decaling.html).
Tube protectors came from a blokey in HK on ebay IIRC.
Thanks, wet stick is really just making me angry, so I will try this, the other thing I was going to try were black tee shirt iron on..
Quote from: juansolo on May 17, 2011, 04:01:14 PM
(http://juansolo.demon.co.uk/stompage/images/philcaster-i.jpg)
(http://juansolo.demon.co.uk/stompage/images/boobtube-i.jpg)
I'm assuming the all alike wiring colors is to drive people like me mad, and so that people (also like me) can't figure out how you've gone and done it.
Beautiful work though, amazingly tidy.
That Aside, If you don't mind me asking, is that bright switch adding a bypass cap to a cathode, or changing a coupling cap or...?
Those are pretty!
@ Thundershowers
The bright switch changes the input cap as it could get a tad dark with humbuckers. The boobtube has an in-between input cap to compromise.
The all one colour wiring is because that's the 100m reel of wire that I'll have been using at the time :) I ran out of purple and am now on orange.
Quote from: CheopisIV on May 17, 2011, 09:10:04 PM
Quote from: iccaros on May 17, 2011, 04:39:38 PM
Sorry I must be stupid.. when you connect your voltmeter (your pannal VU )you plug one side into your i/o box and then have no cable, but the other probe is connected to the valve caster?
if so you not measuring volatge, as voltage can only be measured over a load. http://physics-tutor.site90.net/drupal/node/29 (http://physics-tutor.site90.net/drupal/node/29), that would be measuring current, which If I remember my EE coursed from 20 years ago, a VU will read amp or milliamp in this configuration.
as for voltages, if these are read from pin to ground with tube in, well they are low for the plates.. I would expect 7 volts or so, are you running this through a voltage regulator, and why are you running it off a SAG power supply, the last thing we want in a starved plate design is low battery simulate, which is what your sag is doing. .That is cool on some old effects pedals, but kills head room on this pedal.
Lol, no, i doubt you're stupid. I think i just described it wrong! It sits in parallel between my I/O box and the breadboard, There are two wires into it (V+ and Ground) and two wires out of it to my breadboard (V+ and ground). The purpose of the 'sag' knob is to dial my 18V adapter down to 12V (or 9V, etc), not to starve the Valvecaster. It works perfectly on any other circuit, but the Valvecaster acts funny.
An interesting thing happened and I think (hope) it's the issue. I was checking to make sure none of my components were touching each other and when I wiggled the input cap, i heard a scraping noise.... This breadboard has a metal plate on the bottom and is supposed to have a shield between it and the board, so I shouldn't have heard the scraping sound. I think I have to rip it down and check my board... I'm thinking there may be something grounding out under there. As soon as I get the time, I'll have to rebuild. Thanks everyone for the comments and tips.
Beautiful pedal a few posts up too! I love seeing other people's creations!
can you put of pictures of your Bread board.. maybe get another set of eyes on it.
juan, nice works as always! Mind to share the mods you made to the original schem in the scond pedal!?
I took some action shots of the breadboard few days back, just need to find time to put them on the pc. I tore the board down last eve and the backing is intact so my grounding theory is out the window. I had the VC apart so rebuilt it according to the pcb-less schematic, still does the same thing to my power supply, so there goes the too-many-wires theory too! Another oddity though, this new build sounds fantastic, but my volume pot does nothing... I probably fried something while soldering. I also took voltages and then tried a different brand tube, then got a bunch of different readings. I'm thinking that maybe these tubes are just a bit far gone and that's the reason for the odd behaviour on the first build? More dissection is needed!
:icon_eek: ...if I were a bit smarter, I might have noticed the ground from the remaining Volume lug... Also getting this off the breadboard and into an enclosure for kicks. Pictures to come, but there wont be any fancy decals yet. I want to work out all the bugs before I worry about pretty.
Quote from: CheopisIV on May 19, 2011, 05:12:46 AM
:icon_eek: ...if I were a bit smarter, I might have noticed the ground from the remaining Volume lug... Also getting this off the breadboard and into an enclosure for kicks. Pictures to come, but there wont be any fancy decals yet. I want to work out all the bugs before I worry about pretty.
Have you seen my videos? I am all good with function over form..
Quote from: Renegadrian on May 18, 2011, 05:36:02 PM
juan, nice works as always! Mind to share the mods you made to the original schem in the scond pedal!?
There's still a little crackle when the gain pot is turned, not as bad as altering the tube bias on the original, but maybe another resistor to ground on the 2nd triode grid will make it better. I might try it at the weekend.
I don't think the 150n caps are a critical value, I had a few from a bulk buy, and wanted to use them up, had them 2 years and never used. A 100n or 220n would probably work just as well.
I also tried a JJ ECC83 in this and it worked well, unlike when I've tried them in a regular valvy. Not sure if its the 23V or the mods. A 5963, 12BH7, and ECC83 all worked and all sounded good, all different in terms of gain and bass though.
(http://www.maccentral.demon.co.uk/schematics/boobtube.jpg)
I have problem. Tube socket holes are lower than tube pins.
I tried to cut lower the pins and I break tube .
I tried to filing another tube pins. Filing tangled pins. Filing it slower is slow process and it can also tangle pins.
What to do ?
Quote from: Death Super Mario on May 19, 2011, 07:59:31 AM
I have problem. Tube socket holes are lower than tube pins.
You may have accidentally got solder inside the socket...
Quote from: merlinb on May 19, 2011, 09:16:07 AM
Quote from: Death Super Mario on May 19, 2011, 07:59:31 AM
I have problem. Tube socket holes are lower than tube pins.
You may have accidentally got solder inside the socket...
No this is excluded. Tube socket holes are not long as the tube pins.
Quote from: Death Super Mario on May 19, 2011, 10:18:31 AM
No this is excluded. Tube socket holes are not long as the tube pins.
Then the socket is bad, replace the socket.
Quote from: merlinb on May 19, 2011, 10:28:58 AM
Quote from: Death Super Mario on May 19, 2011, 10:18:31 AM
No this is excluded. Tube socket holes are not long as the tube pins.
Then the socket is bad, replace the socket.
In Estonia I have to be happy that I can buy right function tube and some socket.
In Estonia many things what is in other countries buyable is not on sale.
Quote from: Death Super Mario on May 19, 2011, 11:56:09 AM
In Estonia I have to be happy that I can buy right function tube and some socket.
In Estonia many things what is in other countries buyable is not on sale.
Then leave it alone. You already broke one valve, which probably cost more than another socket...
juan, thx for posting the schem! 12BH7 you say, I got a couple and I like them!!!
Quote from: juansolo on May 19, 2011, 06:48:07 AM
I don't think the 150n caps are a critical value, I had a few from a bulk buy, and wanted to use them up, had them 2 years and never used. A 100n or 220n would probably work just as well.
Hmmm, Those caps are pretty lowish, those alone should cut bass... Doth you have sound clips?
Quote from: juansolo on May 19, 2011, 06:48:07 AM
Quote from: Renegadrian on May 18, 2011, 05:36:02 PM
juan, nice works as always! Mind to share the mods you made to the original schem in the scond pedal!?
There's still a little crackle when the gain pot is turned, not as bad as altering the tube bias on the original, but maybe another resistor to ground on the 2nd triode grid will make it better. I might try it at the weekend.
I don't think the 150n caps are a critical value, I had a few from a bulk buy, and wanted to use them up, had them 2 years and never used. A 100n or 220n would probably work just as well.
I also tried a JJ ECC83 in this and it worked well, unlike when I've tried them in a regular valvy. Not sure if its the 23V or the mods. A 5963, 12BH7, and ECC83 all worked and all sounded good, all different in terms of gain and bass though.
(http://www.maccentral.demon.co.uk/schematics/boobtube.jpg)
try putting the pot behind the coupling cap.. This way current through the pot is not heard on the input of the next stage.
actualy if you put a cap between the pot and the grid it should cure the crackle. At voltages this low the grid starts conducting pretty easy and the cap should block it from the pot. You can use it to shape tone if you want as well. I would start with a bigger one though. .047uf should be fine i would bet.
Will have to have a play at the w/e and see if we can eliminate the crackle.
Sadly I've got no way of making any clips :(
Quote from: Brian_L on April 29, 2011, 11:45:23 AM
I don't get any hum, I have the 15v going through a capacitor/7812/capacitor setup, and it's really clean
Actually the output is powering all my pedals at 12v
I was wondering how you wired it. I had the 35V side going to the anodes and the 15V side going to the filament. I used a 7812 to convert the 15V to 12V. All I got was a loud hum with all the HP printer adapters. All of the grounds were connected properly. When I went back to the 15V radio shack adapter there is no hum
Quote from: Anon on May 20, 2011, 01:57:57 PM
Quote from: Brian_L on April 29, 2011, 11:45:23 AM
I don't get any hum, I have the 15v going through a capacitor/7812/capacitor setup, and it's really clean
Actually the output is powering all my pedals at 12v
I was wondering how you wired it. I had the 35V side going to the anodes and the 15V side going to the filament. I used a 7812 to convert the 15V to 12V. All I got was a loud hum with all the HP printer adapters. All of the grounds were connected properly. When I went back to the 15V radio shack adapter there is no hum
that is filtering, I bet you money if you put the HP power supply to a o scope you would see a ac spike from the Switching power. Make sure your adapters say filtered and not switching.. Computers can having low frequency switching.. as they are no bothered by the noise at those frequencies. but audio equipment.. That is another story..
I have a 30v dc adapter from RS that is dead quite. but hook up the HP printer one and I get noise..
Well putting the cap after the pot failed completely. It started to fart out when hitting the strings hard, so its gone back to before the pot.
I'll put up with the crackle. I compared it to an original VC and its much less, so not an issue to me.
If I make another I'll have a little experiment, but for now it stays as is. It sounds fantastic.
Quote from: juansolo on May 23, 2011, 11:10:13 AM
Well putting the cap after the pot failed completely. It started to fart out when hitting the strings hard, so its gone back to before the pot.
I'll put up with the crackle.
You need a cap before and after the pot, AND a resistor from grid to ground (about 100k), if you want to eliminate the crackle.
I was going to add a resistor to ground on another build, but not the second cap. Thanks Merlin. I'll give it a go.
I assume its the lack of any DC on the grid that causes the issues when the cap is after the pot?
Quote from: juansolo on May 23, 2011, 11:27:56 AM
I was going to add a resistor to ground on another build, but not the second cap. Thanks Merlin. I'll give it a go.
I assume its the lack of any DC on the grid that causes the issues when the cap is after the pot?
Yes, if you have no resistor after a coupling cap then you will get a 'charge pumping' effect every time the grid draws current on positive half-cycles, because the cap has no resistor to discharge through on negative half-cycles. This causes the farting noises you hear!
the issue is current through the pot as I have found with no coupling @ all you get the same noise.. With a capacitor the cap will discharge or charge as current changes so it cancels the current changes of the pot.
That is the theory I am sticking with.. :icon_biggrin:
I agree you need the grid leak resister as the pot was doing that before, but I would try between 100K as suggested and 500K .. @ these voltages its not really necessary for the tube as it is in higher voltage setups but it acts like a pull down resistor. You could also do a pull up instead, between 600K and 1M to +12. This would give a like effect, but is more radical to your design.
That took 5 minutes, and works perfectly. My ears are ringing, I thought the amp was on the gain channel, but it was on the clean, this thing is SO loud!
Thanks Merlin.
Quote from: iccaros on May 22, 2011, 11:19:14 AM
Quote from: Anon on May 20, 2011, 01:57:57 PM
Quote from: Brian_L on April 29, 2011, 11:45:23 AM
I don't get any hum, I have the 15v going through a capacitor/7812/capacitor setup, and it's really clean
Actually the output is powering all my pedals at 12v
I was wondering how you wired it. I had the 35V side going to the anodes and the 15V side going to the filament. I used a 7812 to convert the 15V to 12V. All I got was a loud hum with all the HP printer adapters. All of the grounds were connected properly. When I went back to the 15V radio shack adapter there is no hum
that is filtering, I bet you money if you put the HP power supply to a o scope you would see a ac spike from the Switching power. Make sure your adapters say filtered and not switching.. Computers can having low frequency switching.. as they are no bothered by the noise at those frequencies. but audio equipment.. That is another story..
I have a 30v dc adapter from RS that is dead quite. but hook up the HP printer one and I get noise..
Is there something I can build to filter out the hum?
Quote from: Anon on May 23, 2011, 02:32:26 PM
Quote from: iccaros on May 22, 2011, 11:19:14 AM
Quote from: Anon on May 20, 2011, 01:57:57 PM
Quote from: Brian_L on April 29, 2011, 11:45:23 AM
I don't get any hum, I have the 15v going through a capacitor/7812/capacitor setup, and it's really clean
Actually the output is powering all my pedals at 12v
I was wondering how you wired it. I had the 35V side going to the anodes and the 15V side going to the filament. I used a 7812 to convert the 15V to 12V. All I got was a loud hum with all the HP printer adapters. All of the grounds were connected properly. When I went back to the 15V radio shack adapter there is no hum
that is filtering, I bet you money if you put the HP power supply to a o scope you would see a ac spike from the Switching power. Make sure your adapters say filtered and not switching.. Computers can having low frequency switching.. as they are no bothered by the noise at those frequencies. but audio equipment.. That is another story..
I have a 30v dc adapter from RS that is dead quite. but hook up the HP printer one and I get noise..
Is there something I can build to filter out the hum?
http://www.beavisaudio.com/projects/Huminator/index.htm
If its in the audio range?? you would have to filter on the power input. If you had a scope you could see what frequency was spiking as you are most likely hearing a harmonic from the heater and roll that off. other wise you are guessing. Look at your adapter, does it show two output voltages as mine does.. It may be heterodyning and which case no.. http://en.wikipedia.org/wiki/Heterodyne (http://en.wikipedia.org/wiki/Heterodyne)
Hi, I'm new in electrics and I built the pedal according to the schematic:
Quote from: dano12 on December 13, 2007, 09:31:09 AM
(http://www.beavisaudio.com/Projects/ValveCaster/MatsuminValveCasterWiring.gif)
The tube lights up but I only get noise from the pedal. If I turn the volume pot to max it stops, but nothing else happens.
What could be the problem?
I think I might have soldered C3 in the wrong direction. The positive leads to pin 6 doesn't it?
yep. + on pin 6 and - on the tone pot. Check r1 and r4 as they are often culprits of no sound. got a picture to look at? that helps. if not, look back some pages and get the voltages to compare.
Got some pics (finally) Breadboard and boxed up. Next hurdle, fancy decal!
Here's a link to the album.
---> LINK (https://picasaweb.google.com/mrsnifter/ValvecasterBuild001?authkey=Gv1sRgCI324Oz2srrWKQ&feat=directlink) <---
edit:
(Was going to link pics, but this computer is limiting me and I can't get direct links to work properly. Will try again when I get home!)
Quote from: CheopisIV on May 23, 2011, 07:45:53 PM
Got some pics (finally) Breadboard and boxed up. Next hurdle, fancy decal!
Here's a link to the album.
---> LINK (https://picasaweb.google.com/mrsnifter/ValvecasterBuild001?authkey=Gv1sRgCI324Oz2srrWKQ&feat=directlink) <---
edit:
(Was going to link pics, but this computer is limiting me and I can't get direct links to work properly. Will try again when I get home!)
what voltage do you have on the heater? I have only seen them shine that bright when the voltage is high
I'll put the voltages up later tonight as well, but they're not far off the last ones I posted. This particular tube lights up a lot compared to some of the others I've had in the circuit. This was taken with the 12V adapter just for the glow effect, they're not nearly as bright at 9V.
put leds under them....they look nice lit up. ;)
Quote from: deadastronaut on May 23, 2011, 09:12:37 PM
put leds under them....they look nice lit up. ;)
I wanted to put a green one under it but my sockets are all a bit different; this one had way too small a hole for my 5mm LEDs to fit! Some of my other sockets are a perfect fit though, so on my next one I'll be doing it for sure. They do look badass with the LED underneath though!
(http://i55.tinypic.com/307p0gn.jpg)
I never did Show this. Custom Stainless box I made for these. Don't ask for one, it's not cost effective.
Quote from: ThunderShowers on May 23, 2011, 09:19:38 PM
(http://i55.tinypic.com/307p0gn.jpg)
I never did Show this. Custom Stainless box I made for these. Don't ask for one, it's not cost effective.
I like it... ;D
Quote from: CheopisIV on May 23, 2011, 09:07:21 PM
I'll put the voltages up later tonight as well, but they're not far off the last ones I posted. This particular tube lights up a lot compared to some of the others I've had in the circuit. This was taken with the 12V adapter just for the glow effect, they're not nearly as bright at 9V.
if you are running it off 12v your good, and I have a LED to make mine bright also.. so I like it.. My pot on my lm317 died when mine got that bright..
(https://lh3.googleusercontent.com/-jNSiWw5LIak/TdrvVXefTrI/AAAAAAAAAUI/qyu0oN17P2E/VC02.JPG)
(https://lh6.googleusercontent.com/_PYEL0Q5k7Nw/TdrvVWGiW6I/AAAAAAAAAUM/T8rfa8wZJb0/VC03.JPG)
(https://lh4.googleusercontent.com/-48UpWFBRzh8/TdrvUvrj6ZI/AAAAAAAAAUE/uPiiFWg0QCk/VC04.JPG)
Here we go! Heaters are at 12.33 on this one, but it's an unusable adapter due to the whine. I have an order in to Mouser for a bunch of parts for some charge pump/regulator kits though, so I'm hoping to put something together for a functional 12V Valvecaster with low noise and higher output. I run it off a 9V 400ma adapter to play with.
I'm so in love with this pedal, such a clear and useable boost! It retains my Tele twang like no other boost can and even plays real nice with my Les Paul. I'm going to let a friend use it at his next band practice tomorrow; gonna be hard to hand it over!
Quote from: juansolo on May 23, 2011, 01:27:54 PM
That took 5 minutes, and works perfectly. My ears are ringing, I thought the amp was on the gain channel, but it was on the clean, this thing is SO loud!
Thanks Merlin.
Updated schematic. May need to refresh browser.
(http://www.maccentral.demon.co.uk/schematics/boobtube.jpg)
Quote from: CheopisIV on May 24, 2011, 01:37:32 AM
I have an order in to Mouser for a bunch of parts for some charge pump/regulator kits though, so I'm hoping to put something together for a functional 12V Valvecaster with low noise and higher output. I run it off a 9V 400ma adapter to play with.
I suppose that you are starting this project off with a REGULATED adapter?
You are not going to get rid of the whine without a regulated adapter or some form of filtering circuit.
Quote from: Govmnt_Lacky on May 24, 2011, 08:43:25 AM
I suppose that you are starting this project off with a REGULATED adapter?
You are not going to get rid of the whine without a regulated adapter or some form of filtering circuit.
Yeah, the 9V adapters are regulated and filtered, but the 12V is from an external HDD and whines like a stuck pig. I also have an old 18V laptop adapter that works well with no noise.
Quote from: ThunderShowers on May 23, 2011, 02:52:36 PM
Quote from: Anon on May 23, 2011, 02:32:26 PM
Quote from: iccaros on May 22, 2011, 11:19:14 AM
Quote from: Anon on May 20, 2011, 01:57:57 PM
Quote from: Brian_L on April 29, 2011, 11:45:23 AM
I don't get any hum, I have the 15v going through a capacitor/7812/capacitor setup, and it's really clean
Actually the output is powering all my pedals at 12v
I was wondering how you wired it. I had the 35V side going to the anodes and the 15V side going to the filament. I used a 7812 to convert the 15V to 12V. All I got was a loud hum with all the HP printer adapters. All of the grounds were connected properly. When I went back to the 15V radio shack adapter there is no hum
that is filtering, I bet you money if you put the HP power supply to a o scope you would see a ac spike from the Switching power. Make sure your adapters say filtered and not switching.. Computers can having low frequency switching.. as they are no bothered by the noise at those frequencies. but audio equipment.. That is another story..
I have a 30v dc adapter from RS that is dead quite. but hook up the HP printer one and I get noise..
Is there something I can build to filter out the hum?
http://www.beavisaudio.com/projects/Huminator/index.htm
I built the Huminator and it didn't work. the HP adapters still hum like crazy. the adapters are old so they must be the switching type. I was wondering what are the model numbers of the the regulated HP adapters.
Quote from: Anon on May 25, 2011, 02:15:59 PM
Quote from: ThunderShowers on May 23, 2011, 02:52:36 PM
Quote from: Anon on May 23, 2011, 02:32:26 PM
Quote from: iccaros on May 22, 2011, 11:19:14 AM
Quote from: Anon on May 20, 2011, 01:57:57 PM
Quote from: Brian_L on April 29, 2011, 11:45:23 AM
I don't get any hum, I have the 15v going through a capacitor/7812/capacitor setup, and it's really clean
Actually the output is powering all my pedals at 12v
I was wondering how you wired it. I had the 35V side going to the anodes and the 15V side going to the filament. I used a 7812 to convert the 15V to 12V. All I got was a loud hum with all the HP printer adapters. All of the grounds were connected properly. When I went back to the 15V radio shack adapter there is no hum
that is filtering, I bet you money if you put the HP power supply to a o scope you would see a ac spike from the Switching power. Make sure your adapters say filtered and not switching.. Computers can having low frequency switching.. as they are no bothered by the noise at those frequencies. but audio equipment.. That is another story..
I have a 30v dc adapter from RS that is dead quite. but hook up the HP printer one and I get noise..
Is there something I can build to filter out the hum?
http://www.beavisaudio.com/projects/Huminator/index.htm
I built the Huminator and it didn't work. the HP adapters still hum like crazy. the adapters are old so they must be the switching type. I was wondering what are the model numbers of the the regulated HP adapters.
Any one with two voltages will likely heterodyne. Try a single voltage one and one that if had a led takes a second to power up.. On the side note Radio Shack has a 30volt DC with a switch to make it 13
Welp, from 9 volt to 24 volt. I. I'm blown away.
Question, how many problems Would I create by doing this (http://i52.tinypic.com/29mubyh.gif) for the input bright switch.
It lets some of the full signal bypass through the resistor so the input is less mud, while all the highs go through the cap, still having some full low end there. (47kr works good for even more brightness) Just wondering if the parallel Resistor could cause harm somewhere in the path..?
i have a question for you ;D
i saw that the tone pot adjusts the trebble,but i want to add another pot that gives me the posibility to adjust the bass because sometimes the valvecaste is just to bassy-where should i put that pot ? and what value should it be?
Well, my above post is a bright switch, which will cut the bass at the very beginning of the signal chain.
I don't really see why putting the input as a pot lug #2, and putting each one of those caps on either lug, then to pin 2 of the 'castor wouldn't work.
EDIT: apparently, It doesn't. Herp derp, i guess I need help as much as you.
And Now i have three knobs, all of which can be described as "Gain" I am on a total Roll right now.
Quote from: ThunderShowers on May 30, 2011, 08:16:08 PM
Well, my above post is a bright switch, which will cut the bass at the very beginning of the signal chain.
I don't really see why putting the input as a pot lug #2, and putting each one of those caps on either lug, then to pin 2 of the 'castor wouldn't work.
EDIT: apparently, It doesn't. Herp derp, i guess I need help as much as you.
And Now i have three knobs, all of which can be described as "Gain" I am on a total Roll right now.
Once you lift the to ground part of the pot, then it becomes an adjustable resistor with either booting bass or treble through the tube.. So in effect a Gain pot.
but go to page 29 of this link --> [URL]http://www.freewebs.com/valvewizard1/Common_Gain_Stage.pdf[\URL]
Read this.. It explains a lot.. you can ignore the math on the first reading to get to what you want.
Quote from: iccaros on May 30, 2011, 10:59:24 PM
Quote from: ThunderShowers on May 30, 2011, 08:16:08 PM
Well, my above post is a bright switch, which will cut the bass at the very beginning of the signal chain.
I don't really see why putting the input as a pot lug #2, and putting each one of those caps on either lug, then to pin 2 of the 'castor wouldn't work.
EDIT: apparently, It doesn't. Herp derp, i guess I need help as much as you.
And Now i have three knobs, all of which can be described as "Gain" I am on a total Roll right now.
Once you lift the to ground part of the pot, then it becomes an adjustable resistor with either booting bass or treble through the tube.. So in effect a Gain pot.
but go to page 29 of this link --> [URL]http://www.freewebs.com/valvewizard1/Common_Gain_Stage.pdf[\URL]
Read this.. It explains a lot.. you can ignore the math on the first reading to get to what you want.
haha, I'll read it again, I suppose. Gotta get a Good tone knob somehow.
~failed post~ please delete it
(http://i51.tinypic.com/nytsld.png)
I personally like the 64 uf (In my case, bargain bin caps from the locals stores old stock.)
Clean headroom on the second stage, so you can max out that and then edge in the first stage to get a nearly clean boost (Totally clean with a 12ay7)
Tone control is the same style as the old Fender Deluxe; Treble Cut on one end, bass cut on the other, and a nice middle ground. I'm not sure if the values are 100% the best, but they do WORK.
(http://i56.tinypic.com/f39so9.jpg)
like it ThunderShowers
I like the folding metal accents. good work
Quote from: iccaros on June 01, 2011, 11:52:29 PM
like it ThunderShowers
I like the folding metal accents. good work
Fact: they're to cover where I wasn't thinking and drilled holes in the wrong spot. :icon_redface:
Notes on that build: The tone control hardly works with the Sovteks; I don't get much low end with them.
Late to the party - I *did* bring a bottle, though...
My board is currentl lacking 'Mojo', and I was all-set to build a(nother) Rangemaster.
I found an NPN Ge device, and was about to start breadboarding, until I saw this.
Am currently waiting for some 9-pin sockets and a 12AT7 to arrive. this looks like an excellent project - thanks to Matsumi, Dano and everyone else who has chipped in with mods / add-ons etc.
The only issue I have is *mounting* the Tube.
My current thought it so have the socket on a pair of (1cm / roughly 1/2" - or as long as can be fitted) screws, inside a standard (BB) sized box. This way, at least *some*of the Tube is out of harm's way, but is not physically sat (shorting) against the bottom of the box. Mounting from the top also negates the need to drill cooling-vents into the top of the box, and will most likely give a quick and easy Tube change.
The screws will be fixed to the top of the box with lock-nuts, and again round the socket's "ears" (above and below), so as to minimise any knocks / bangs.
Does anyone have any opinions on this?
Cheers!
Quote from: newfish on June 02, 2011, 10:02:32 AMThe only issue I have is *mounting* the Tube.
What you've come up with has been done, and does work. If you want to be a little more adventurous, turn the box sideways in orientation, and put the tube coming out the side, with your input and output jacks on either side of it. If you plug into it with straight connectors, they should shield the tube from the sides, and the tube will be not sticking out where you could stomp on it. It's a chopped down version of my custom made boxes (See page 120.)
Also, try my tone control layout as well as the stock one, I need opinions always.
Quote from: ThunderShowers on June 02, 2011, 07:15:23 PM
Quote from: newfish on June 02, 2011, 10:02:32 AMThe only issue I have is *mounting* the Tube.
What you've come up with has been done, and does work. If you want to be a little more adventurous, turn the box sideways in orientation, and put the tube coming out the side, with your input and output jacks on either side of it. If you plug into it with straight connectors, they should shield the tube from the sides, and the tube will be not sticking out where you could stomp on it. It's a chopped down version of my custom made boxes (See page 120.)
Also, try my tone control layout as well as the stock one, I need opinions always.
Yes - I can see why wouldn't be cost-effective. Cool-looking creature though. Am impressed!
Think I'll stay with the 'top-mount' - as that's within my skills with metal ( \m/ )...
12AT7 arrived today, so just waiting for the sockets now. May get some screens / covers as extra precaution.
Cheers!
Hogod, it sounds good (with the new tweaks) but i still can't play worth shit :icon_redface:
i still want my tone eq and now i found a passive tone corrector-
http://i11.tinypic.com/2ynkzrs.png
will it work installed after the valvecaster? i kow it will cut some of the boost because it's a passive eq but that's not a problem for me ( i will have 2 valvecasters in series so i'll still have an acceptable boost;the advantage of a passive schematic is that it won't produce hiss)
Wow.
Finished, un-boxed as yet, and working.
This is such a simple, excellent build.
The point-to-point aspect is a little fiddly, but Dano's diagram is as clear as can be.
Wired as 'stock', and running a 12AT7 (ecc81), there's a decent amount of grit and boost available.
"We're gonna need a bigger pedal board..."
OK, a new 'JJ' 12AU7 arrived this morning, and I duly put it into my Valvecaster.
With everything at '10', the signal with the pedal engaged is only at Unity.
Swapping out for my original 12AT7 yields more grit and boost, as you would expect given the increase in Mu.
Here are my voltages - does anything look out of place here?
Pin Volts DC
1 6.38
2 0.23
3 0.0
4 0.0
5 9.38
6 7.17
7 0.37
8 0.0
9 4.5 (no connection).
I've checked the valus of all resistors with my DMM, and they all read as 'correct' (i.e. 220K, 470K, 1M etc...).
The only 'sub' I've made is to increase R3 (Pin 6) to 220K for a little more 'push'.
I realise a 100v tube will not boost the same at 9v, but other posters here have commented on the gain available from a 12AU7.
Would anyone be kind enough to suggest how to get more than Unity from a 12AU7 tube in this circuit?
Many thanks,
Ian.
Well I thought id have a crack at this Valvecaster stuff and i have gotta say, I am damned impressed!!!
Here is my tweaked version of one with a JJ.
http://soundcloud.com/bmcguitar/bmc-guitar-effects-tweaked
Definitely going to build one of these and add it to the pedal board for sure.
Recorded using a Alesis Multimix + condenser mic in front of Kustom KCA10 SS Combo attached to a 2x12 Marshall MC212 Cab and 1991 Ibanez RG560
"OK, a new 'JJ' 12AU7 arrived this morning, and I duly put it into my Valvecaster."
The bad news first : I had the same issue with the JJ 12AU7/ECC82. I found out through a discussion in a German forum that the JJ´s just don´t work well at low voltages 12 V.
Indeed on my valvecaster and vanilla overdrive unity with the JJ was at max, the EH 12AU7 adn China 12AU7 don´t have this problem and work well.
Now the good news : set the anode voltage somewhat higher (36 V) and gone is the issue (unity at 9 H !!!).
Quote from: newfish on June 14, 2011, 05:36:47 AM
OK, a new 'JJ' 12AU7 arrived this morning, and I duly put it into my Valvecaster.
With everything at '10', the signal with the pedal engaged is only at Unity.
Swapping out for my original 12AT7 yields more grit and boost, as you would expect given the increase in Mu.
Here are my voltages - does anything look out of place here?
Pin Volts DC
1 6.38
2 0.23
3 0.0
4 0.0
5 9.38
6 7.17
7 0.37
8 0.0
9 4.5 (no connection).
I've checked the valus of all resistors with my DMM, and they all read as 'correct' (i.e. 220K, 470K, 1M etc...).
The only 'sub' I've made is to increase R3 (Pin 6) to 220K for a little more 'push'.
I realise a 100v tube will not boost the same at 9v, but other posters here have commented on the gain available from a 12AU7.
Would anyone be kind enough to suggest how to get more than Unity from a 12AU7 tube in this circuit?
Many thanks,
Ian.
as others have stated IT my be the JJ (been told that long plate tube have issues with lover voltages, but have not tested it), In fact the 12u7 should give you more boost than the higher MU tubes at 12 volts due to its history with the 12u7 and the way it handles current. In my Linear Tube project --> http://www.diystompboxes.com/smfforum/index.php?topic=91745.0
I posted this write up --> http://www.freewebs.com/valvewizard2/Triodes_at_low_voltages_Blencowe.pdf
OK. Thanks.
Found some 12U7s on the internet last night. Have orderd a couple to play with, since this box is intended to run with my existing 9v / 12v split supply. 30v isn;t really an option - unless I employ *another* power supply.
Cheers!
where did you find 12u7? I have been looking for at least 2 more for the 24volt amp I setup... 12au7's work but the 12u7's have more gain.
you may have to bias a little different for the 12u7, changing to a 100K pot instead of the 50 and it stays about 2/3 of the way.
Quote from: iccaros on June 16, 2011, 12:54:52 AM
where did you find 12u7? I have been looking for at least 2 more for the 24volt amp I setup... 12au7's work but the 12u7's have more gain.
you may have to bias a little different for the 12u7, changing to a 100K pot instead of the 50 and it stays about 2/3 of the way.
I thought I'd found some at 'tubedepot', but it turns out that they're on back order. :icon_frown:
'thetubestore' appears to have them for $15 or so, with an availability of 'usually ships within 24 hours'.
No mention of 'waiting for stock'.
Hope this helps.
Hi,
Finally my Valvecaster works!!!!
The problem was the power supply as always.
The fun thing is that a Boss adapter in my country is about 30-35$, but I used my brother's 8 port switch's adapter and it is perfect, and he bought the switch and the adapter for about 10$...so I think I will also buy a switch like this :)
I only have a little noise with it, but I think I will solve this with the transistor mentioned above.
Oh and the gain and the volume pots work reverse, any ideas why?
I found a tube named PCC189 I tried it, it has less gain and less volume, but I like what I heard, I'm thinking of building another valvecaster soon with this. But it also was very hot when I played. First I want to finish this project, a nice housing, maybe a 3PDT switch for true bypass.
Thanks for the help!!!
Quote from: akkor68 on June 18, 2011, 02:02:21 AM
Oh and the gain and the volume pots work reverse, any ideas why?
you wired them backwards.... swap the the outer wires
http://sound.westhost.com/pots.htm (http://sound.westhost.com/pots.htm)
Quote
I found a tube named PCC189 I tried it, it has less gain and less volume, but I like what I heard, I'm thinking of building another valvecaster soon with this. But it also was very hot when I played. First I want to finish this project, a nice housing, maybe a 3PDT switch for true bypass.
Thanks for the help!!!
That is a weird tube, already not linear, want 7.6 volts on heaters and draws 300ma just for heaters.. I would not expect much "Boost" from the load line at these voltages.
http://tubedata.tubes.se/sheets/030/p/PCC189.pdf (http://tubedata.tubes.se/sheets/030/p/PCC189.pdf)
Quote from: iccaros on June 18, 2011, 02:19:32 AM
That is a weird tube, already not linear, want 7.6 volts on heaters and draws 300ma just for heaters.. I would not expect much "Boost" from the load line at these voltages.
http://tubedata.tubes.se/sheets/030/p/PCC189.pdf (http://tubedata.tubes.se/sheets/030/p/PCC189.pdf)
In this kind of situation, you can always use a regulator to get the right voltage... a 7806 with some 1N4007 will do the trick.
_____
[ O ]
|_____|
[ 7806 ]
|_____|
| | |
| | |_______7.4v
12v |
|
_\/_
| 2x 1N4007
_\/_
|
___|___
|_GND_|
Whenever you need an "odd" voltage, like 7v or 13v, you just need to get a regulator for the closest voltage (7806 for 7v, 7812 for 13v, etc) and add diodes to it's "GND" pin.
Each diode adds 0.7v to the output voltage. Just check the difference between your regulator's output voltage to the voltage you need, and divide this difference to 0.7 so you get the number of diodes you'll need.
If you wanna be more precise, you can use schottky rectifiers. These add just 0.1v to 0.2v .
Quote from: tuckster on March 16, 2011, 11:42:55 AM
Ok now it works. I don't know why... I put in a new Pot for R2 becaus ethe last one was realy burned after all these resoldering adventures.
I still got the same pin values for 9V and it also works for 12V but then I obviously have different values.
I tinkered around with R2 and R3 to get a nice sounding pedal. I'm going to post the pictures in the pitures thread.
Yes it worked but it was not very loud. I swaped the JJ tube with a tube-town one and it's much better.
(http://generaledefoutre.files.wordpress.com/2011/06/vge1_psyche.jpg)
my own valvecaster, & first attempt with tube as well...
^ ^ ^
What Lies Beneath...
Good idea to have a kick-plate over your Tube.
:icon_cool:
Quote from: newfish on June 20, 2011, 06:16:21 PM
^ ^ ^
What Lies Beneath...
Good idea to have a kick-plate over your Tube.
:icon_cool:
Yes, playing this weekend, made me want to add a shield to mine.. I use mine to boost my amps distortion for leads.. So after the 4th or 5th song I noticed I was kicking the tube..
Well, a 12U7 arrived yesterday, courtesy of eBay - in its original 'CBS' box...
...and it works *so* well! Plenty of boost available, decent amount of grit in there too.
Thanks once again to all the splendid folks on this forum for the ideas, advice, and intellectual generosity, without which, my pedal board would be really bare.
Cheers!
:icon_cool:
Okay so I'm finally gonna take a crack at this too. Got a couple GE 5814a's that should do the trick.
I'm seeing conflicting reports on boost. Does thing have enough? If this was my one only pedal, would it do the trick or would I need some kind of booster after it?
Quote from: wizbey on June 14, 2011, 07:04:23 AM
Well I thought id have a crack at this Valvecaster stuff and i have gotta say, I am damned impressed!!!
Here is my tweaked version of one with a JJ.
http://soundcloud.com/bmcguitar/bmc-guitar-effects-tweaked
Definitely going to build one of these and add it to the pedal board for sure.
Recorded using a Alesis Multimix + condenser mic in front of Kustom KCA10 SS Combo attached to a 2x12 Marshall MC212 Cab and 1991 Ibanez RG560
Sounds good man! What I would expect to hear, which is a good thing. I hear some underlying fizz I'm not so crazy about, but it still is great for what it is.
this thing has enough boost to raise the level of your guitar for a lead. You can add more gain and it will add some "wool" to the tone of a clean guitar or you can use a semi dirty amp and it will drive an amp into serious distortion. I hope that answers you question.
Quote from: zambo on June 26, 2011, 03:18:28 PM
this thing has enough boost to raise the level of your guitar for a lead. You can add more gain and it will add some "wool" to the tone of a clean guitar or you can use a semi dirty amp and it will drive an amp into serious distortion. I hope that answers you question.
It does! Thanks Zambo. I'm hoping I can get to this one this week. :)
Ok. So, I finally broke down and built a Valvecaster. I have been on the search for a bass overdrive and I think my search is over. I followed the original schematic except I used a 10uF output cap, I did not include the tone control, and I skipped on the master volume control (for now).
I am running it on 9v but I plan on trying higher voltages in the future. After I built it, it was a little "farty" for my taste. I kept trying smaller and smaller input caps and I finally settled on a 1nF cap. This was not the best sounding cap (I lose a little too much bass) but it was the least "farty" sounding one. I checked Jack Orman's RC calculator and it is telling me that a 1nF cap and a 1M resistor will create a high pass filter at 160 Hz. This of course is pretty high but I can add some bass later on in the circuit if I need it.
My question is related to a statement on the RC calculator page, "This calculator assumes a low source impedance, which usually is small enough that it does not change the corner frequency." Since this is right after my bass which is a high impedance source, how do I actually figure out what frequency the high pass filter is?
Edit: I just remembered that I used a 12AT7 (It's all I had). I'm pretty sure that higher voltages and lower gain tubes will allow me to raise the input cap but I gotta work with what I have for now.
to tame farts try and lower the value of the cap from pin 1 to pin 6 and drop your output cap back to 1 uf. .022uf sound great on a lot of stuff for bass. The master volum is nice too. if you are running it wide open its not as good as it could be imho. I like the three knob version for the versatility.
Finally got this boxed up. Built the main board a year ago and have just been adding and changing bits since then.
Valvecaster running on 48v with switchable tremolo. 12ax7 in there at the moment.
No stomp switch as it is the last in the chain and pretty much stays on.
Sounds great in front of my clean SS amp especially when being pushed by a booster.
(http://dl.dropbox.com/u/15632336/lektronix/Photos/Ttube1.jpg)
3 gain modes, clean, dirty and treble boost.
(http://dl.dropbox.com/u/15632336/lektronix/Photos/Ttube2.jpg)
And the guts.
Havn't decided whether to mount the regulator inside the box yet.
Gets quite hot but as the tab on the ic connected to the voltage output pin I can't think how to bolt it to the enclosure but keep it insulated.
(http://dl.dropbox.com/u/15632336/lektronix/Photos/Ttube3.jpg)
Nice, you used this Voltage Multiplier (http://www.diystompboxes.com/smfforum/index.php?topic=74088.140)!!!
Quote from: Renegadrian on July 30, 2011, 09:18:06 PM
Nice, you used this Voltage Multiplier (http://www.diystompboxes.com/smfforum/index.php?topic=74088.140)!!!
Yes, it works really nicely.
I posted a vero layout for it further on in that thread. Simple multiplier using common parts.
Having real trouble getting my one to work, have breadboared it up and get no effect, just noise as if somethings not grounded.......for what its worth, these are my voltages.
Im using a 5963 PHILIPS ECG
1: 2.5
2:0
3:0
4:0
5:2.5
6:0
7:0
8:0
9:1.2
your heater voltages are way too low, what power supply are you using?
Just a greencell 9v battery
depending on how your wire this, but if you take the tube out, on pin 1 and 6 you should see full voltages (with no tube you have no current so with out current you have full voltage)
on the heaters (4 and 5) you should see 9volts between them, with tube in 4 to 5 should be 9 volts. Pin 1 and 6 about 6v
Pins 3 and 8 should be close to zero.
do you have pictures we can see and any changes you may have made.
but I would check your voltage at battery, then trace the routes with ohm meter (turn off the power first)
Quote from: iccaros on August 16, 2011, 09:55:07 PM
depending on how your wire this, but if you take the tube out, on pin 1 and 6 you should see full voltages (with no tube you have no current so with out current you have full voltage)
on the heaters (4 and 5) you should see 9volts between them, with tube in 4 to 5 should be 9 volts. Pin 1 and 6 about 6v
Pins 3 and 8 should be close to zero.
do you have pictures we can see and any changes you may have made.
but I would check your voltage at battery, then trace the routes with ohm meter (turn off the power first)
OK rebuilt the hole thing on the breadboard with fresh parts and a new battery, here are the measurements
9v battery @ 8.77v
Tube out
1: 8.57
2:0
3:0
4:0
5: 8.57
6:0
7:0
8:0
9:0
Tube In
1: 7.01
2:0
3:0
4:0
5: 7.01
6: 3.51
7:0
8:0
9: 3.47
Now getting a hint of signal (not even close to unity), but still lots of noise? :icon_cry:
Sundgist that looks fantastic!
What is that awesome lightening bolt knob on your breadboard?
Just saw this post, WOW o_0
This image on the front page intrigues me:
(http://www.beavisaudio.com/projects/ValveCaster/MatsuminValveCasterWiring.gif)
If I built that, exactly as shown, and plugged it in, would it work? Some show a "heater" but the simplicity and safety(?) of this design are really appealing. Does it take a while to warm up before working? Does it get hot while running?
Quote from: nexekho on August 17, 2011, 03:30:53 PM
If I built that, exactly as shown, and plugged it in, would it work? Some show a "heater" but the simplicity and safety(?) of this design are really appealing. Does it take a while to warm up before working? Does it get hot while running?
Yes it would totally work....
It is not dangerous at these voltages...
It takes about ten seconds to warm up...
And finally,it gets a little hot while running but nothing great!you can even touch the tube... ;)
AWESOME, thanks. Next project once my current distortion is complete will probably be one of these to replace the op-amp booster I'm using.
Quote from: carboncomp on August 17, 2011, 02:20:56 PM
Quote from: iccaros on August 16, 2011, 09:55:07 PM
depending on how your wire this, but if you take the tube out, on pin 1 and 6 you should see full voltages (with no tube you have no current so with out current you have full voltage)
on the heaters (4 and 5) you should see 9volts between them, with tube in 4 to 5 should be 9 volts. Pin 1 and 6 about 6v
Pins 3 and 8 should be close to zero.
do you have pictures we can see and any changes you may have made.
but I would check your voltage at battery, then trace the routes with ohm meter (turn off the power first)
OK rebuilt the hole thing on the breadboard with fresh parts and a new battery, here are the measurements
9v battery @ 8.77v
Tube out
1: 8.57
2:0
3:0
4:0
5: 8.57
6:0
7:0
8:0
9:0
Tube In
1: 7.01
2:0
3:0
4:0
5: 7.01
6: 3.51
7:0
8:0
9: 3.47
Now getting a hint of signal (not even close to unity), but still lots of noise? :icon_cry:
check your wiring to pin 6, that is a plate and should have voltage on it.....
Still having a nightmare with this!
I used this vero layout and still get no effect
(http://i52.tinypic.com/21ergwx.jpg)
Even had a friend play with it who know far more then me, and he had no luck?
(http://i52.tinypic.com/aayxp5.jpg)
Is there any way to test if its the valve thats faulty?
also was testing with unity on my DDM to make sure all the pins where wired right and noticed i get unity betwwn the + and - tracks on my breadboard then the valve in in the socket.....that can be right, can it?
Are the resistors all in the right place?! The two on the right should use 4 rows right?! Also did you remember to cut the track under the first cap!? I guess you should get some sound anyway...did you check pins orientation!? Does pin 5 get voltage?! Check pin 4 and 5 with the DMM...Does the tube glow!? if yes, it gets the heater voltage...
Quote from: Renegadrian on August 18, 2011, 09:48:51 PM
Are the resistors all in the right place?! The two on the right should use 4 rows right?! Also did you remember to cut the track under the first cap!? I guess you should get some sound anyway...did you check pins orientation!? Does pin 5 get voltage?! Check pin 4 and 5 with the DMM...Does the tube glow!? if yes, it gets the heater voltage...
Yes, resister have been checked a hundret times, track is cut and tested with DMM, This is the pin orientation iv been using......am I about to get egg on my face????
(http://i51.tinypic.com/9rtvkn.png)
here are the voltages
tube out
1: 7.79
2:
3:
4:
5: 8.00
6 7.97
7
8
9
tube in
1: 4.91
2:
3:
4:
5: 5.88
6 4.47
7:
8:
9: 2.89
and the plus and minus track are still making my DMM beep in diode mode, when the tube is in?????
voltages look better, but low.. Do you have another tube to test with? if you look in http://www.diystompboxes.com/smfforum/index.php?topic=29816.0 (http://www.diystompboxes.com/smfforum/index.php?topic=29816.0) they show how to make an audio probe to help trouble shoot...
as for testing a tube, well you can measure signal level with a DMM, its not the best, but put a known signal in and measure the AC voltage on say pin 2. then measure AC on Pin 7 you should see gain...
when the tube is in the heaters will look like a short to the DMM so you will get the beep.. as it increases resistance as it heats, and the DMM is not enough to make it heat up :)
your c3 is polarized? I would not use a polarized cap for that..
Tube socket pins are numbered correctly, I disagree about the the c3 cap, an electro can be used with good results, with the - to the pot as is in your picture. Apart from the first one, all the others I built have an electro.
+ 1 on c3 electro. i always use one for c3.
Quote from: iccaros on August 18, 2011, 11:45:01 PM
voltages look better, but low.. Do you have another tube to test with?
No I dont, guess I better order one :(
just checked everything, cap and resister values, pin out put, even the tracks on my breadboard.
Plugged it into my larger amp, and get a faint sound, and can here changes in the volume and gain knob......but its a whisper even with the amp at 11.
You used a battery...8.77V...please understand that a circuit like this works a lot better with a wall wart...and some regulation...take a wall wart!!! The circuit is hungry for current, the more the better...500mA is mandatory, if you have a 12V 1A as myself it's even better...
Another BoobTube (valvecaster variant), this time with a stompable boost stage.
(http://juansolo.demon.co.uk/stompage/images/sinistube1-o.jpg)
(http://juansolo.demon.co.uk/stompage/images/sinistube2-o.jpg)
(http://juansolo.demon.co.uk/stompage/images/sinistube-i.jpg)
this i am liking very much! you know, i've never considered the humble u-bolt as an alternative to the chrome handles or little 'tower' style of protectors seen on many of you guys' valvecasters. thanks for the pics!
See, I have this little wastepaper basket kicking about (looks like this: http://us.123rf.com/400wm/400/400/swalwellj/swalwellj1010/swalwellj101000006/8015262-a-silver-mesh-waste-paper-bin-with-blue-paper-spilling-from-it.jpg (http://us.123rf.com/400wm/400/400/swalwellj/swalwellj1010/swalwellj101000006/8015262-a-silver-mesh-waste-paper-bin-with-blue-paper-spilling-from-it.jpg)) it's about the size of a cup and very sturdy. When I finally build this, I'm probably gonna mount the tube inside it using a pair of L brackets with a helltonne of LEDs. Can't wait :D A vacuum tube should be fine if it's being stored and used upside down right?
Quote from: rutabaga bob on August 22, 2011, 12:44:59 PM
this i am liking very much! you know, i've never considered the humble u-bolt as an alternative to the chrome handles or little 'tower' style of protectors seen on many of you guys' valvecasters. thanks for the pics!
We're liking the U bolt a lot lately: http://juansolo.demon.co.uk/stompage/images/aod2-o.jpg (http://juansolo.demon.co.uk/stompage/images/aod2-o.jpg) (poor pic because it was dark and hand held).
Quote from: Renegadrian on August 20, 2011, 07:27:37 PM
You used a battery...8.77V...please understand that a circuit like this works a lot better with a wall wart...and some regulation...take a wall wart!!! The circuit is hungry for current, the more the better...500mA is mandatory, if you have a 12V 1A as myself it's even better...
.
Whoa back up please. 500mA???? I thought only about 150mA @ 9VDC would be ample.
i haven't been in on the rest of your posts, but if this is regarding building a valvecaster with any of the 12__7 tubes, the heater current is 150ma alone on most if not all of them, wired series. (pin 4 and 5). the 12bh7a uses 300 ma heater current. save yourself a headache, and use a 500ma or 1 amp wall wart, then filter and regulate it.
I want to include some LEDs to illuminate the enclosure running off the same power supply. From what I can tell, three standard LEDs in series with a 200R resistor should be optimum for the LEDs. If I put that chain of components running straight from +9V to ground, will it just draw the extra current needed to illuminate the LEDs or will it cause problems with the rest of the circuit?
Thanks.
Sorry to be a total dunce, I've started building my first valvecaster from the following schematic. I've noticed that Pin 4 of the valve is not connected to anything. Can some one please either draw in or explain to me where i connect pin 4 to and what modifications i need to make.
Kind Regards
Gram
(http://lh3.ggpht.com/-0JBqURl75UI/S5NE8G9zh7I/AAAAAAAAAg8/FnxaQmUWbM8/s512/vc-p-t-p-layout.gif)
Not checked if it's the same schematic, but on this diagram I plan to build mine from, it's grounded.
(http://www.beavisaudio.com/Projects/ValveCaster/MatsuminValveCasterWiring.gif)
Thank you Mr Wild. Already figure it out. It sounds a chunk better running on 12V rather than 9. Maybe it's just me. Any way this is my humble first attempt at one.
(http://26.media.tumblr.com/tumblr_lqltlg5L2n1qkz75no1_500.jpg)
Quote from: Gramatron@mac.com on August 27, 2011, 03:17:11 PM
Sorry to be a total dunce, I've started building my first valvecaster from the following schematic. I've noticed that Pin 4 of the valve is not connected to anything. Can some one please either draw in or explain to me where i connect pin 4 to and what modifications i need to make.
Kind Regards
Gram
(http://lh3.ggpht.com/-0JBqURl75UI/S5NE8G9zh7I/AAAAAAAAAg8/FnxaQmUWbM8/s512/vc-p-t-p-layout.gif)
Pin 4 is coonected to ground in your drawing... with 5 positive.
you can flip these as they do not matter as long as one is negative and the other positive.
I think it sounds better @ 20 + volts, but you have to change the heater wiring.. (pin 4 and 5)
Built my 2nd successful Valvecaster today. I use a 12V 700mA power supply from my keyboard, regulate the voltage with a 7812 (I prefer running the heaters at 12V :P), and a TC1044 to based on Rick's Murder One Low Voltage Tube Amp designhttp://www.diystompboxes.com/smfforum/index.php?topic=71381.0 (http://www.diystompboxes.com/smfforum/index.php?topic=71381.0).
I have 42.8V going to my plate resistors (the 220k and 100k) opening up some headroom. Changed my input cap to 33nf, and output cap to 222nf. Thought the output seemed a little thin, IMHO I also use a modified gain control, with a 0.68 50V electrolytic cap from lug 2 to ground on the variable ground stage. (For me I use pin 8, I remember reading somewhere that pins 6-8 are better for the first triode gain stage, most likely earlier in this massive thread!)
Howls when I max the gain and volume out, so going to tweak it abit more until Im completely satisfied, I will post my results.
newbie here. some very beautiful an impressive work on this board! I really enjoy browsing through this thread.
I was going to try making this basic valve caster for my bass. Ive got a parts list and schematics, but have one question:
i am using this diagram:
(http://www.idylwilde.net/tmp/MatsuminValveCasterWiring.gif)
So this seems pretty staightfoward so far. However, i also need the wiring diagram to hook everything into the stomp /bypass switch. Also, do i need to use a terminal strip (i have seen this in some boxes) this is not indicated in matsumin's schematic. Any help would be greatly appreciated and start me happily on my way to becoming a pedal addict!
brett
This one looks nice!
(http://www.beavisaudio.com/techpages/StompboxWiring/StompboxWiring96.gif)
I've built a couple of valvecasters, but none of them play well with my active bass... if i put a simple JFET buffer in front do you think that would help?
Quote from: runmikeyrun on August 30, 2011, 03:18:25 PM
I've built a couple of valvecasters, but none of them play well with my active bass... if i put a simple JFET buffer in front do you think that would help?
Well an active bass has a buffer? right? What is it you do not like about the sound?
Speaking of basses, does anyone have a suggestion as to what input/output capacitors would work well with a bass. I hear higher values are good.
I used my first one with stock value caps and it sounded good...higher values will let some more bass freqs pass in, so I'd say a 100nF won't harm...or even higher, up to electros...
Greetings All
Real noob here, I have been reading this thread for 2 months and decided to have a go of it. Built two valvecasters, one with standard componets
and one for clean boost. I have made several SS amps and have made 12 LM3886 amps. Tubes are more fun!!!. My goal is to add a tube preamp
to a Lm3886 for a guitar amp. Don't fully understand matching input with output yet. What I have done is to make a revised pcb from page 19,
use CNC to fab. boards. I also made a PCB layout from the schematics on pages 77,119 and 120 with two verisons, one with single supply and one with
12v and 24v supply. I don't know how to convert my cad files to pdf just yet, will share these files when I learn how. Many thanks to all that have
contributed to this creation, it is truly awesome!!!!!!!
Quote from: runmikeyrun on August 30, 2011, 03:18:25 PM
I've built a couple of valvecasters, but none of them play well with my active bass... if i put a simple JFET buffer in front do you think that would help?
I doubled c1,c2,c3 and changed c4[tone cap] to 47nf...try different values to get what you like...47nf gives you a deep tone but not too muddy...
Quote from: iccaros on August 30, 2011, 11:14:36 PM
Quote from: runmikeyrun on August 30, 2011, 03:18:25 PM
I've built a couple of valvecasters, but none of them play well with my active bass... if i put a simple JFET buffer in front do you think that would help?
Well an active bass has a buffer? right? What is it you do not like about the sound?
The sound is harsh, non-musical distortion, thin and weak, almost splattery like a misbiased transistor. It works great with passive basses and guitars.
Quote from: runmikeyrun on September 01, 2011, 11:40:48 PM
Quote from: iccaros on August 30, 2011, 11:14:36 PM
Quote from: runmikeyrun on August 30, 2011, 03:18:25 PM
I've built a couple of valvecasters, but none of them play well with my active bass... if i put a simple JFET buffer in front do you think that would help?
Well an active bass has a buffer? right? What is it you do not like about the sound?
The sound is harsh, non-musical distortion, thin and weak, almost splattery like a misbiased transistor. It works great with passive basses and guitars.
I put a basic opamp buffer in front, but you could also try making the first stage a cathode follower
also raising voltage may help, I found that mine sounded that way until I got over 24Vdc.. getting ready to rebuild mine at around 80 volts..
A bit of a n00b question, but my DC jack has only two pins, which correspond to + and - on the power brick. Is attaching the ground loop to the - ok or is it wrong?
Thanks.
(about 65% through a build here)
Completed the circuit! Built it, checked it, jacked it up, WORKED FIRST TIME. :icon_eek:
(http://i.imgur.com/6YTZ6.jpg)
Next step: box it up.
Clips a bit harsher than I expected but it's pretty easy to dial it back.
Thanks for all your help and the schematics!
uhm sorry...what is that?! What are those green LEDs for!?
I moved caps 1, 2 and 4 to a board because my poly boxes have really short legs and added three LEDs which sit at the top of the tube and light it up.
It's a mess at the moment.
Quote from: Renegadrian on September 02, 2011, 01:51:46 PM
uhm sorry...what is that?! What are those green LEDs for!?
are you thinking what i'm thinking? Clipping diodes? :icon_eek: :icon_eek:
Quote from: iccaros on September 02, 2011, 03:32:46 AM
Quote from: runmikeyrun on September 01, 2011, 11:40:48 PM
Quote from: iccaros on August 30, 2011, 11:14:36 PM
Quote from: runmikeyrun on August 30, 2011, 03:18:25 PM
I've built a couple of valvecasters, but none of them play well with my active bass... if i put a simple JFET buffer in front do you think that would help?
Well an active bass has a buffer? right? What is it you do not like about the sound?
The sound is harsh, non-musical distortion, thin and weak, almost splattery like a misbiased transistor. It works great with passive basses and guitars.
I put a basic opamp buffer in front, but you could also try making the first stage a cathode follower
also raising voltage may help, I found that mine sounded that way until I got over 24Vdc.. getting ready to rebuild mine at around 80 volts..
Thanks Steve for the input. I just built Jack Orman's JFET buffer/splitter. I will try that in front of my one valvy to see if there's a difference. It definitely made a difference in front of my big muff clone. If that doesn't do it, i will head to goodwill and try to find a 24v laptop PS. I only have an 18v one here.
I'm curious on that note... I used a 7812 VR on my last build. I couldn't put more than 18v into it because I'm pretty sure it would fry. How can i get 12v to run the heaters from 24v? Can i just wire two tube's heaters in series or do I have to worry about hum?
Quote from: runmikeyrun on September 03, 2011, 10:20:01 AM
Quote from: Renegadrian on September 02, 2011, 01:51:46 PM
uhm sorry...what is that?! What are those green LEDs for!?
are you thinking what i'm thinking? Clipping diodes? :icon_eek: :icon_eek:
No! They're just in series with a current limiting resistor on the same board with a second switch to turn them off, the whole subcircuit running in parallel with the tube drive across the jack. Works perfectly. In my arrangement, the jacks and switches are at the bottom, then the tube, then the board with the caps and the LEDs points down the tube lighting it up green and then the dials are up the top.
Quote from: nexekho on September 03, 2011, 12:30:09 PM
Quote from: runmikeyrun on September 03, 2011, 10:20:01 AM
Quote from: Renegadrian on September 02, 2011, 01:51:46 PM
uhm sorry...what is that?! What are those green LEDs for!?
are you thinking what i'm thinking? Clipping diodes? :icon_eek: :icon_eek:
No! They're just in series with a current limiting resistor on the same board with a second switch to turn them off, the whole subcircuit running in parallel with the tube drive across the jack. Works perfectly. In my arrangement, the jacks and switches are at the bottom, then the tube, then the board with the caps and the LEDs points down the tube lighting it up green and then the dials are up the top.
Right on! The valvecasters I built I super glued a very bright LED into the middle of the base of the tube socket. When the effect was on the tube lit up.
Quote from: runmikeyrun on August 30, 2011, 03:18:25 PM
I'm curious on that note... I used a 7812 VR on my last build. I couldn't put more than 18v into it because I'm pretty sure it would fry. How can i get 12v to run the heaters from 24v? Can i just wire two tube's heaters in series or do I have to worry about hum?
A 7812 would work but need heat sink, I think it can drop up to 35V... but I don't have the datasheet in front of me. if you use the to-3 package the pedal housing can be the heat sink, with the normal package you need a separation or use negative voltage regulator.
using V= I*R
you want to drop 12 volts, the heaters pull .15 amps so
12/.15 = 80 ohms,
take current and resistance (.15 * 80 = 1.8 watts)
so a 2 watt would work, 3 - 4 better.
In either case you have to give off 1.8 watts of power so heat sin
cool... thanks for the info. I don't like using voltage regulators in tube circuits though, i always have problems with hum. Can i just run the heaters in series @ 24v? That would be much easier for me.
Quote from: runmikeyrun on September 03, 2011, 10:40:32 PM
cool... thanks for the info. I don't like using voltage regulators in tube circuits though, i always have problems with hum. Can i just run the heaters in series @ 24v? That would be much easier for me.
if you have two tubes.. one tube in series is 12V and 6.3 in parallel
cool, thanks... that's what i thought. I do plan on using two 12au7s. If i can find a higher supply, i'll use more tubes. You can never have enough gain! lol
EDIT- I just thought of something. Provided i have enough current, can i tap voltage for the plates and heaters from one transformer? Or should I have two separate ones? I don't want to induce any noise or hum.
EDIT (again!)- Ok Radio Shack has a 12v transfomer at 450ma and a 25v transformer at 450ma. How many tubes can I power safely with each of those? I would use the 12v for heaters and 25v for the plates. I know the twincaster I built wasn't happy with anything less than a 1A supply @ 12v, otherwise i had sag, but that was with the heaters and plates running off the same wall wart.
Quote from: runmikeyrun on September 04, 2011, 01:46:42 PM
cool, thanks... that's what i thought. I do plan on using two 12au7s. If i can find a higher supply, i'll use more tubes. You can never have enough gain! lol
EDIT- I just thought of something. Provided i have enough current, can i tap voltage for the plates and heaters from one transformer? Or should I have two separate ones? I don't want to induce any noise or hum.
EDIT (again!)- Ok Radio Shack has a 12v transfomer at 450ma and a 25v transformer at 450ma. How many tubes can I power safely with each of those? I would use the 12v for heaters and 25v for the plates. I know the twincaster I built wasn't happy with anything less than a 1A supply @ 12v, otherwise i had sag, but that was with the heaters and plates running off the same wall wart.
see here --> http://www.diystompboxes.com/smfforum/index.php?topic=74088.0 (http://www.diystompboxes.com/smfforum/index.php?topic=74088.0)
A simple voltage multiplier would be better, I pick up 1amp 12V wall warts at Good Will for less than $3
Feed the plates off the multiplier and the heaters off the 12V input.
Those are interesting. I'm going to do some experimentation when I get the cash to pick up a few tube sockets and a couple of those trannies. Maybe try out a nixie supply too. I figure with 4 tubes the enclosure will be a little larger than normal anyways, so I should have room for two small trannies. I also have a small single ended stereo amp in the basement, might look at that PT to see what kind of taps it has.
also I did this project with 12V
Worked well for me, would like others to test and give me feedback to improve it.. its a 12ax7 and 6au6 pentode on 12v
I added an opamp buffer in front of the 12ax7, unity gain so it just effected the input loading.
http://www.diystompboxes.com/smfforum/index.php?topic=91745.0
that's an interesting circuit... i'm going to investigate. It's possible i have a 6au6 in my basement... I have a couple of oddball tubes floating around and that sounds familiar. Thanks for the link!
Point me in the right direction if this has been said before BUT....
Just been reading through this thread. I have just finished building the tube boost! It sounds cool but the amount of "boost" I get is quite small. Is this common? I get a nice bit of crunch but not much boosting action. Running it of my bench power supply, set to 9V.
Cheers!
what, you didn't read all 125 pages?? :icon_lol:
You're talking about the volume output when the effect is engaged, right? You should be getting more than what you're getting when bypassed. I got a decent amount of boost out of mine. Maybe your tube might be at the end of it's life? Try a different 12AU7 and see what happens. Also, did you perform any mods to the circuit?
I got through about 35 of them! Then I was hoping people on the board would not be too harsh with my question :).
Its just a little bit more than what you get when bypassed. Maybe ill order a new 12AU7. No modifications. Built it on the socket. Get quite a bit of hum also which might be due to the wiring?
Cheers for the comments!
yeah you should be getting a decent amount of boost. Hum is almost always a power supply deal.
I had to use laptop power supplies to get rid of hum. I found pretty much any wall wart will have some level of hum to them. You can find laptop power supplies at thrift stores in the states for a couple of bucks.
I found this circuit to have no noise at all when running through an amp even with my brother's strat copy which has major interference problems when ran into a POD. Using a Roland 9v wall wart.
hey. I am about to start on my build for the valvecaster. Before I start I was hoping someone could verify that this schematic is correct and will work:
(http://www.idylwilde.net/tmp/Valvecasternylayoutmkabler.jpg)
thanks very much
QuoteI was hoping someone could verify that this schematic is correct and will work.
You might want to put a resistor in series with the LED. (Didn't look at anything else)
+1 on the resistor. i use 4.7k for that. not sure if thats the norm. The rest looks pretty good but hard to tell with the switching.
Use a calculator to determine the correct resistor.
http://ledz.com/?p=zz.led.resistor.calculator (http://ledz.com/?p=zz.led.resistor.calculator)
Quote from: brett25 on September 06, 2011, 01:46:32 PM
hey. I am about to start on my build for the valvecaster. Before I start I was hoping someone could verify that this schematic is correct and will work:
thanks very much
It looks like there is an issue with your layout, signal is shunted over c3 to ground. there is no way I can see it would pass through the tone and volume pot.
this layout works -- notice the differences
see (http://www.beavisaudio.com/Projects/ValveCaster/MatsuminValveCasterWiring.gif)
see schematic and trace connection in the layout --> (http://www.beavisaudio.com/Projects/ValveCaster/MatsuminValveCaster.gif)
thanks iccaros,
I see that now. So if I route the C3 into tone 3 and across to volume3, is that the only issue?
however Krinor has followed the C3 wiring as shown in my diagram, so that leads me to belive it also works that way:
(http://www.idylwilde.net/tmp/Valvecasterinterir.jpg)
thanks
any other thoughts? I could switch this part of the wiring but I have also seen a couple of otheres using it the other way, so I was hoping someone who has done it could verify. Im a tube noob, and am trying to avoid having to trace problms later.
your wiring looks far more orderly than anything I can ever manage. I didn't see any errors myself, but I do not claim perfection. Hope it works for ya
I would switch it,
The issue, in my mind is the tone strait to ground, while others may get volume, I bet if you hooked it to a scope, you would see that signal drops dramatically before and after the cap. So they may not be getting as good a sound as possible, I do not even seeing it work, will have to put on my board as the resistance after the cap is higher than strait to ground.
Its not about tubes, all electronics work the same way, what we used to say, is that it will find the quickest path to ground. We now know that electrons flow from ground and go to positive, but its hard for people to picture their electronics working that way. :)
so we have a path that is easier for electrons to flow over than from the end of this chain.
Plus he has pin one and 3 of the volume pot to ground.. I say that does not work no matter what is drawn, I would have to hold it in my hands and use it before I believe it works...
but put it on a bread board and see..
sorry, don't mean to sound harsh.. I just electrically do not see that layout working, could be wrong...
that layout make the schematic look like this
(http://dl.dropbox.com/u/14312589/MatsuminValveCaster.gif)
thnaks iccaros, i appreciate your advice! will let you know how it turns out
HI.
Quote from: iccaros on September 06, 2011, 03:44:28 PM
It looks like there is an issue with your layout, signal is shunted over c3 to ground. there is no way I can see it would pass through the tone and volume pot.
this layout works -- notice the differences
see (http://www.beavisaudio.com/Projects/ValveCaster/MatsuminValveCasterWiring.gif)
see schematic and trace connection in the layout --> (http://www.beavisaudio.com/Projects/ValveCaster/MatsuminValveCaster.gif)
Layout shows schematic to be like this:
(http://img685.imageshack.us/img685/6061/matsuminvalvecaster.gif)
It's electrical correct.
Actually... according to the schematic you posted, C3 is in Series with C4 to the Tone pot. According to the layout, you show C3 going straight to the Tone pot Lug 3 and C4 going to the wiper of the Tone pot ???
So, the layout and schematic you posted ARE NOT electrically the same ;)
To make them the same, you need to connect C3 from Pin 6 of the tube DIRECTLY to Lug 3 of the VOLUME pot. Then, install C4 from Lug 3 of the Volume pot directly to Lug 3 of the Tone pot. Then, connect Pins Tone pot Lugs 1 and 2 along with Volume pot Lug 1 to Ground.
Gain pot is also wrong. Tube Pin 3 should go to Gain pot Lug 3. Gain pot Lugs 1 & 2 go to ground.
The layout does NOT match the schematic at all!!
Hi
I have not not read all of the posts so far. I read about the first 16 and then decided to post my question.
I built the circuit on a bread board, as originally posted and all was fine. (As I play bass I played around with capacitor values and settled on doubling all the values).
The heater was connected positive to pin 5 and earth to pin 4, giving 9V over both heaters. The circuit works well and is quiet.
I read the discussions regarding heater voltages and decided that a tweak could be in order. I wired up a LM317 voltage regulator to give 6.3V on the output, connected the output to pin 9 and pins 4&5 to earth. from what I understand this should be correct. Now I have a hum ???
Any suggestions to trouble shoot.
Bryan
Quote from: BryanC on September 10, 2011, 09:59:04 AM
Hi
I have not not read all of the posts so far. I read about the first 16 and then decided to post my question.
I built the circuit on a bread board, as originally posted and all was fine. (As I play bass I played around with capacitor values and settled on doubling all the values).
The heater was connected positive to pin 5 and earth to pin 4, giving 9V over both heaters. The circuit works well and is quiet.
I read the discussions regarding heater voltages and decided that a tweak could be in order. I wired up a LM317 voltage regulator to give 6.3V on the output, connected the output to pin 9 and pins 4&5 to earth. from what I understand this should be correct. Now I have a hum ???
Any suggestions to trouble shoot.
Bryan
Hi Bryan.
Well you know the old saying.... if it ain't broke, don't fix it.
Go back to what worked! Try to get 9V out of the regulator and hook it back up in series.
If you STILL get the hum, then you need to look at your regulator circuit. Maybe some caps may be in order.
Good Luck ;D
P.S. You should try to put 12V in series on the heaters. It will maximize the life of the tube. Hence the 12xx7. 12V for heater power.
Quote from: BryanC on September 10, 2011, 09:59:04 AM
Hi
I have not not read all of the posts so far. I read about the first 16 and then decided to post my question.
I built the circuit on a bread board, as originally posted and all was fine. (As I play bass I played around with capacitor values and settled on doubling all the values).
The heater was connected positive to pin 5 and earth to pin 4, giving 9V over both heaters. The circuit works well and is quiet.
I read the discussions regarding heater voltages and decided that a tweak could be in order. I wired up a LM317 voltage regulator to give 6.3V on the output, connected the output to pin 9 and pins 4&5 to earth. from what I understand this should be correct. Now I have a hum ???
Any suggestions to trouble shoot.
Bryan
I'm not sure about actually using pin9 of the 12AU7. As I understand it... running voltages from pin5 to pin4 (the tube heaters) can take 6.3V at 300mA or 12.6V at 150ma. Although I totally understand your attempt apply a 6.3V PS Voltage at pin9, it seems leaving it as a "No Connection" seems the safest route to pursue. Furthermore I agree with Govmnt_Lacky's addage; don't change what you've got that works. It's a great quote for life in general, and especially moreso in electronics IMHO. Hum is almost always creeping in on your tube heaters in the Valvecaster (once again in my experience and opinion. I've built 3 of them myself.)
A quick fix suggestion.... Remove the V+ connection from pin-9, leaving pin-9 as a no connection. Remove the ground from pin 5 (its the pin I use in mine for V+), and place your 6.3V power connection coming from your LM317 there. That should fix it outright, I believe. Best of luck, ToNy
^Tony...
You may want to reconsider that. The 12-series tubes are rated for ~12V at the heater to maximize the tube's life. The way that Bryan has the heater connected right now is in parallel. Technically that should be OK however, since he is getting the HUM now.... I would recommend that he goes back to what worked and apply the 9V in SERIES as he had it on the breadboard. Better yet, try to run closer to 12V as this is what the tube is spec'd for and will prolong the life of the tube.
the 12A*7 serries tube is made for 12.6 and 6.3 volts. depending on how you wire it.. Which way you wire does not matter, in most amps they are wired in parallel using 6.3 volts. but never 9v in parallel, as that can burn out the heater windings
The 12A*7 series has two heaters in it, each heater wire is required to heat its triode's cathode to have electron flow (they are dual triode tubes)
pins 4, 5, and 9 are connected to the heaters like this
pin 4-----heater wire-----\
|---------> pin 9
pin 5----heater wire------/
pin 4 and 5 are connected through each lines heater where pin 9 is attched to both heaters ends, acting like a center tap between them
so If you connect pin 4 to say positive voltage and pin 5 to negative you are running in serries, and will need to drop 6.3 volts on each heater. Which means you need 12.6 volts.. note 12 is close enought and you get 6 volts on each heater
if you were to connect pins 4 and 5 together and put at positive voltage and pin 9 to negatice, you are running parallel, and you need 6.3 volts..
note heaters are rated at +/- .3 but lower is ok as long as the tube works, higher voltages will burn out the heater..
so wrap up.. These tubes work at both 12 and 6 volts, all dependin on if you are serries or parallel, and neither wiring has anything to do with noise.
I thought (some) noise was dependent on AC vs DC on the heaters and how you route the wires inside the pedal.
how you route wires can always add noise,
AC makes more noise than DC on heaters as that AC frequency can bleed inside the tube. But for most amps, DC is a pain to do for heaters, plus if you need to elevate them, well more issue come up.
but wiring parallel or in series has little to do with it.
plus these are tubes, you will get some noise, they are microphonic, and can act like an antenna.
I have mine on a APC ups to keep my amps and stuff clean..
Quote from: iccaros on September 10, 2011, 12:04:55 PM
if you were to connect pins 4 and 5 together and put at positive voltage and pin 9 to negative, you are running parallel, and you need 6.3 volts..
...
so wrap up.. These tubes work at both 12 and 6 volts, all dependin on if you are serries or parallel, and neither wiring has anything to do with noise.
Problem solved.
I had pins 4 & 5 to ground and pin 9 at 6.3V. I think this might have caused a ground loop? I took pin 9 to ground and pin 4&5 to 6.3V. :-*
Hello,
Im getting ready to build my first valvecaster and had a quick question.... I am going to use an 18.5 volt wallwart power supply feeding a voltage regulator for
12 volts to the Heater using a 7812 voltage regulator. Is it possible to run another wire off the Vin at the full 18.5 volts to feed the plates? or does
the voltage to the plates need to go through the 12 volt regulator as well...... I was thinking a few more volts on the plates would help.... sort of like this:
18.5v-------Vin-------------------18.5v---> (Tube Plate)
-
-
-
-
-
v
7812 regulator 12v ---------->(tube heater)
Vin would be one of those input jacks where the wallwart connects to the pedal
Hello to all tubeheads,
My first tube project - please help! :)
I wonder if a change of R4 to 560Kohm can make the circuit make high-pitched noise and no other sound at all. I can post pics of my creation - my circut is just really messy because I scavanged parts from an old 70-ies stereo.
Quote from: smitty on September 10, 2011, 09:33:31 PM
Im getting ready to build my first valvecaster and had a quick question.... I am going to use an 18.5 volt wallwart power supply feeding a voltage regulator for
12 volts to the Heater using a 7812 voltage regulator. Is it possible to run another wire off the Vin at the full 18.5 volts to feed the plates?
Yes you can do exactly that, although it must be a regulated wall wart or the thing will hum like crazy. If its unregulated then you'd better run the plates from the 12V reg.
(http://www.elportal.pl/forum/download.php?id=2045&sid=3ebe32f844d9b65d6e715a5f4083b644)
ECC81 = 12AT7
ECC82 = 12AU7
ECC83 = 12AX7
Quote from: smitty on September 10, 2011, 09:33:31 PM
Hello,
Im getting ready to build my first valvecaster and had a quick question.... I am going to use an 18.5 volt wallwart power supply feeding a voltage regulator for
12 volts to the Heater using a 7812 voltage regulator. Is it possible to run another wire off the Vin at the full 18.5 volts to feed the plates? or does
the voltage to the plates need to go through the 12 volt regulator as well...... I was thinking a few more volts on the plates would help.... sort of like this:
18.5v-------Vin-------------------18.5v---> (Tube Plate)
-
-
-
-
-
v
7812 regulator 12v ---------->(tube heater)
Vin would be one of those input jacks where the wallwart connects to the pedal
Adding more voltage to the plates will certainly help the 12AU7 which is designed to run at higher voltages of course. I run my main valvecaster with a TC1044 as a voltage multiplier giving me 42.4V at the plates. I LOVE the added headroom, it really opens the pedal up! The TC1044 idea came from Rick Holt's "Murder One Amp" http://www.diystompboxes.com/smfforum/index.php?topic=71381.0 (http://www.diystompboxes.com/smfforum/index.php?topic=71381.0)
ToNy
thanks thereminator
I bought 15 6n2p tubes off ebay for $12.. so I was going to see how that worked in my pedal, your post is a good reminder for people to check the datasheet when doing things outside the original design, like using diffrent tubes, or changing how you wire heaters.
6N2P are similiar to 12AX7 except heater. Pin 9 is a shield between triode systems and must be grounded.
I have finished the build. I left the wiring on the volume and tone lugs so i can switch them atound for testing purposes . Everything else is soldered in. Could anyone tell me which power adapter I need to get to make this run. I have a 12V AC adapter but that doesnt work. Can anything have been damaged from AC power?:
(http://www.idylwilde.net/tmp/01.jpg)
The Electrolytic if you exceeded their voltage.. but probably not
you need DC.. Go ol DC 12v make sure you which is pos and Neg..
hi icarros, do you know the polarity based on my wiring. it looks like center positive?
looks negative tip,but I do not use those DC plugs so I could be wrong. but I would use a DMM or Volt Meter or a Batt to test first,
by the way i left the lug 3 volme/tone unsoldered just for fun and i will try the wiring both ways and let you know how it goes. i think this will be good info for others on this forum
hi another quick question and possibly my last as the pedal is working :icon_biggrin:, but with loud hum. :icon_eek:
Does anything need to be rewired to operate at 12VDC? If im using the stock layout, should I run it only at 9VDC or will 12 v work with no mods? I tested it with an unregulated 12VDC adaptor (getting humming), and plan on getting a regulated one tomorrow, but dont know if I should go 12 or 9V.
Im sure this has been asked but its extreemly hard to search this enormous thread for specific answers (although I have beeen through it entirely once). Thanks again peeplz for the assistance and I will post pics of the completed build! :icon_razz:
brett
Brett25
Nothing needs to be re-wired to run the Valvecaster at DC 12V. All my power supplies are unregulated, and my first build hummed profusely. Stuck a 7812 (positive 12V voltage regulator) in the power section and removed all that atrocious humming.
If you have the option, IMHO, I would go with a 12V supply. If you can't find a regulated PS anywhere invest in some voltage regulators (like 7812, or LM317). I have used both sucessfully in my Valvecaster builds for power supply filtering, and am quite pleased with the results they have provided. Best of luck always, ToNy
thanks tony, thats very encouraging to hear since im getting a good tone through this thing along with the hum. I willl try with a 12VDC regulated power suply and if that doesnt do it, will use a 7812 regulator. thanks for your help
the humming was the power supply, you must get a regulated power supply i would now advise others. there is absolutely no noise now and the sound is great.
Most welcome! And congrats on your success!
I recently built a lo-fi Arduino DSP. It uses a PWM square wave to approximate an analogue output. (which it doesn't have) Obviously this needs some degree of filtering to not destroy whatever you plug it into and soften the harsh digital tone. I find the Valvecaster (stock as in first page wiring diagram) 's tone dial to be perfect for this. At about 50% you get a harsh digital tone (which is great for some things) and then as you roll it around to 90% you get something about right and beyond that it's so dampened it sounds like lo-fi analogue. If I just lifted the entire back end of the schematic, tone dial and volume dial, and put it after the Arduino, would produce the same filtering? I realise it's just a normal low-pass, but there's probably other factors involved I don't know about or understand. Also, if I only find the ~50% least trebly side useful, would swapping the 100k tone pot out for a 47k (can't get 50 easily here) map that range to the whole pot?
Thanks!
good to see people still reading the thread. Unfortunately, I haven't been inspired to make my valvecaster yet. I am thinking about getting some veroboard and doing Renegadrian's layout very soon. Recently moved apartments and had a chance to re organize all my parts, so it should be a little more orderly this go 'round. Thanks eveyone. ALso, does anyone sell homemade boxes on Ebay? I was wondering what the 'normal price' for tube and tubeless pedals would be with a blank aluminum case? I sold one fuzz for around 50USD and the customer was suprisingly happy with it. Just a thought, or if you could point me to a thread about it. Thanks. 8) 8) 8)
-Bill
i sold a twincaster on ebay for $50. It wasnt worth my time after the cost of parts. I only sold it because I wasn't using it.
2nd Boobtube (http://juansolo.demon.co.uk/stompage/schematics/Valve%20Casters/BoobTubeSchematic.jpg). We're now sending 40v to the plates (still 12v to the heaters and 15v to the Klon buffer on the output). It's given it a noticable and worthwhile increase in headroom and taughtness from 23v. Well worth it. As was snagging a RCA 12AU7A cleartop. It's the closest tube we've found so far to the Brimar 12BH7 in mine.
(http://juansolo.demon.co.uk/stompage/images/boobtube2-o.jpg)
(http://juansolo.demon.co.uk/stompage/images/boobtube2-i.jpg)
The perfboard layout is really nice!
Good job! ;)
I've found on web similiar project:
http://kocickamia.rajce.idnes.cz/Tiny_Blue/#
Quote from: thereminator on October 02, 2011, 06:03:58 PM
I've found on web similiar project:
http://kocickamia.rajce.idnes.cz/Tiny_Blue/#
That looks like a full voltage device, not a starved plate.. So its not really the same..
Edit
Sorry, at 30volts, your right, but I would not put the transformer in the case..
NEVER put a transformer in a stompbox! Very dangerous, especialliy on stage!
Why?
if something goes wrong you can have 120v/240v at 15 amps at your feet. Its is never recommended that home builders, more so that most DIY's know little about electronics, interface with wall power directly.
Its safer to use a wall wart.
you know your own skill level, so do what you want, but I like to separate my wall power from something drunk fans with beer in hand can spill all over me and my stuff.
Uh...
Safety is most important. I agree.
Valvecaster variant (Boob Tube (http://www.madbeanpedals.com/forum/index.php?topic=1899.0))
This project came out pretty good, but next time i will locate the jacks closer to the switch. Still don't have a proper tube (anyone know a decent source for 12bh7's?) On board charge pump upto 35v with a 12v supply
(https://lh5.googleusercontent.com/-Y4K9dWwpJTw/To4SsoQg6DI/AAAAAAAAHLk/QyMvPmbAL9A/s640/DSC02867.JPG)
(https://lh6.googleusercontent.com/-pR6xZKOoxbc/To4TD2dgWpI/AAAAAAAAHLo/W13Z0P9l9i0/s400/DSC02866.JPG)
why did you mount the switch that high?! that's the main problem I believe...There's lots of room if you put the switch right noxt to the lower side of the enclosure...you wasted a lot of room that way!!!
true. I used my standard drilling template, i also don't like the aesthetics of the switch being that low. I will probably move the switch down a little on my next one instead of moving the jacks. Thanks for the observation :)
Hello,
I am going to build dual valvecaster with TL071. Here are some drawings of my next project could you please check it? I need know orientation of pots there are some links I used:
http://www.jer00n.nl/2010/07/28/clean-boost-for-guitar-or-bass/ TL071 Preamp
http://www.diystompboxes.com/smfforum/index.php?topic=63479.msg544289#msg544289 Tonestack
full schematic,PCB,Wiring are here:
I drew pots but some of them are incorrectly connected so let me know about that.
http://www.mediafire.com/?9dgpy9uvc3ybqaj
Is there any chance that it will work? :-\
Thanks a lot. //greetings from Slovakia//
Ok I found one mistake it was on PCB the end of power supply that last condenser
There is it fixed and it contains Adobe Illustrator file too.
http://www.mediafire.com/?85xqxm4h5v7584l
Is there somebody who can tell me what is orientation of pots? And how to find out that, when i will do something like that in future?
I am waiting for response I will appreciate it.
Howdy friends. I'm benching this circuit with an 18.5V notebook PSU and a 12AX7 (sounds better to me than the 12AU7), with .022uF caps. R2 of 220K up to 1M sounds about the same. Is V1B grid-leak biased? I played in the wee lower left-hand corner of the characteristics chart and think a 5600R cathode resistor would just about center bias all .084mA. Then can use Ck for a mid+treble boost.
Anyone try Ck Rk for V1b instead of ground? I've only read about 100 pages off and on for the last few days, so I may have missed this.
Thx for a cool site!
CHAD
Used an Rk of 5000 ohms and haven't decided on Ck value - leaning toward a .68uF. I left g1b at 470K. Before the change, at full gain there was too much compressive sag at the onset of a big humbucker chord. It is still just noticable, but OK.
CHAD
Chad- just a suggestion, but if your contemplating several options for Ck may I suggest adding a SPDT switch to allow you to flop between two selections. Like the 0.68uf (with Rk of 5k-ohms, it looks like its full boosting at frequencies above 46Hz) and for the treble boost capacitor 0.022uf (1447Hz). (This mod is on my valvecaster, toggle switch for two capacitors [Ck] and a pot for variable resistance.)
And I'm no expert, but if you have this breadboarded it should be simple to test, about the compression sag try adding some series resistance to the signal entering the each triode grid and see if that helps tame the compression. Not sure if that will help or make it worse, honestly. I'm with you, read so many pages I get confused as to what I remember. I put the RE- in REsearch. :icon_twisted:
Best of luck, ToNy
I need some help with my valvecaster it has a low output with very mild gain.
I am using a 12ax7 and a question I have is how does a tube actually distort?
As in how would you build a circuit that really drives the tube. and what is actually
causing that delicious breakup?
12ax7 will act funny in this circuit a lot of times. Try 12au7. works better at low voltage. if you really want to drive this thing you need more voltage one way or the other. Put a clean boost in front of it and crank it is the easiest way to get more out of it.
I'm running a 12AX7 with an 18.5V notebook power supply and it sounds very nice. Sounded nice with the original schematic, and customized with some different caps and such.
CHAD
12ax7 can be hit and miss in my experience. I have some that work good at low voltage and some may not work at all. 12au7 works consistently well at low voltage. YMMV. :icon_wink:
@ Lightning - check your voltages against some of the posted voltages in this forum and make sure you built it correctly. re flow questionable solder joints and look at resistor values. make sure you dont have polarized caps backwards etc. if all of that stuff is correct i would say its the tube. as far as distortion goes, thats a huge discussion but from what i understand it has a lot to do with the signal getting amplified so much it actualy causes the tube to malfunction and work incorrectly causing harmonics and the valve shuts off (signal clipping) momentarily. there are much smarter people on here that can explain it better i bet :)
Finally got round to buiding my first Twincaster. Seems to work fine (everyone's asleep so can't try it at any kind of volume) but is it normal for gain 1 to crackle a bit? - It's a new pot
(http://www.stallibrass.com/images/avp1.jpg)
totaly normal. Its because of the way it works by changing the bias of the tube.
I like your work! What's that switch for!?
Thanks Renegadrian, you got me started on all this a couple of years back. The switch is merely swapping C1 - I'm using 4.7 & 47nf in my valvecaster so though I'd put the same in this one. Will check out the sound later & adjust to taste.
4.7n - you got a sort of treble booster this way, do you!?
More of a bass cut (I think). I'm using on old vintage valve amp (Roost) which has some very serious bass. I like having a good level of bass for my bypassed sound but this leads to some serious booming when the overdrive kicks in. The 4.7/47 was just trial and error to limit the bass frequencies and give me a switchable choice This worked well on the single valvecaster - I use that as a serious boost, amp on about 8 (preamp) valvecaster full up on everything (lovely vintage overdrive tones) then turn down the guitar vol for a clean sound. I wanted a little more distortion hence the twincaster. This seems to give me the same as the valvecaster when Gain 1 is fully down but increases distortion as it is turned up. Just what i wanted.
Only issue is that I seem to have a loose connection somewhere in the new unit. works fine for a while then looses output slowly & descends into a nasty crackle, almost like a cap discharging. Moving the wiring about seems to get it back but no matter how many i replace or resolder, the problem persists. May be down to the valve bases which in this case are really low quality Chinese items with loose terminals....
(http://i206.photobucket.com/albums/bb54/seedlings/vcjs1.jpg)
18.5V 1940s Tung Sol black glass 12AU7. Makes the old Ibanez TS9 and Fulltone Fulldrive sound very grainy.
CHAD
Er - HELP please (lack of knowledge & all that) I've successfully build a valvecaster but am having an issue with my first twincaster. I'm getting a kind of sagging when i hit a power chord. Originally, i was using a couble of physically small 1uf 63 caps at c3a & c3b. Using these the signal would completely cut out and would come back after a few seconds. I replaced them with 2 physically larger caps which were also marked 1uf 63. This reduced the effect dramatically but it's still there. I had thought that the 63 refered to volts so why the difference in size? both types are radial. C 1, 2 & 4 are all small ceramic disks
Am i looking in the right place or have I overlooked something?
Thanks
Probably wrong place....it might reduce the hum because the caps were of higher quality...
@ Stalik- what tubes are you using? Sometimes anything but a 12au7 will act like that. Not always though. Solder joints is my first guess. When you replaced the caps maybe you moved a wire or part with a cold solder? just guessing. Good luck.
@ Zambo 12AU7 (NOS JAN 5963) work fine in the single valvecaster. Just tried putting the old smaller radial caps back in & sure enough, the cutout returned. Put the larger ones in and it's far better again. i've put a couple of long posts into the vero so that I can quickly swap the caps over so not suspecting poor soldering (this time). I used metalised film caps on the single valve unit so will try to get a pair of them tomorrow to check them out. looking at the gut shots on this forum, it appears that many are using 400v 1uf caps.
my basic theory gives me to understand that a cap filters frequency as a byproduct. It's main use is to store an electrical charge. I think the tiny units I was using simply did not store enough to cope with the demands of a bass rich powercord.
i think that's whats meant by the phrase 'smoothing capacitor' but hey ho, I really am out of my depth so that might all be rubbish!
if I'm right however, this might give rise to the possibility of a switchable sag circuit as it kind of sounds like a valve amp running out of steam...
Quote from: stallik on November 02, 2011, 04:34:16 PM
Er - HELP please (lack of knowledge & all that) I've successfully build a valvecaster but am having an issue with my first twincaster. I'm getting a kind of sagging when i hit a power chord. Originally, i was using a couble of physically small 1uf 63 caps at c3a & c3b. Using these the signal would completely cut out and would come back after a few seconds. I replaced them with 2 physically larger caps which were also marked 1uf 63. This reduced the effect dramatically but it's still there. I had thought that the 63 refered to volts so why the difference in size? both types are radial. C 1, 2 & 4 are all small ceramic disks
Am i looking in the right place or have I overlooked something?
Thanks
What is your power supply. with two 12AU7 the heaters are going to use up 300 - 600 MA depending on how you wired them. Then you have 2 -3 ma per triode which is not much and another 2ma for rest, so a .5 amp power supply may sag. The Cap differences could explain the same effect, as the CAPS charge and discharge as the power sags..
if you are voltage multiplying, you can be using more power.. as to increase voltage you eat up amperage.
@ iccaros -
My power supply is 1.2A so I should have plenty of headroom. nevertheless, I take on your point that it could be the PS. I will take a very carefull look tonight to ensure that I've not got some kind of short? that's dragging it down
OOPS! Think I may have found the cause of my problem. I've been working to the wrong layout. On mine, R1b is missing. ::) Will solder one in there this evening & keep my fingers crossed
lol yeah that would do it. glad you found the prob. :)
wow this pedal rocks!!
I use 1A 12V power supply and a 12ax7 (I don't know what you guys are wining about, it boosts the amp beautifully :) )
I only have a tiny question.
this pedal runs on a very low voltage. how long the tube's life will probably be, without smashing the pedal with a sledgehammer?
Hmmm...i am not an expert on tubes however a cheap tube i believe would keep good for around 2-3years?(with daily use)
Most tube datasheets provide hours of life....You should ask there! ;D
Quote from: deblacksin on November 03, 2011, 04:14:07 PM
wow this pedal rocks!!
I use 1A 12V power supply and a 12ax7 (I don't know what you guys are wining about, it boosts the amp beautifully :) )
I only have a tiny question.
this pedal runs on a very low voltage. how long the tube's life will probably be, without smashing the pedal with a sledgehammer?
Sadly different 12ax7', even from the same run, can react differently at low voltage, and of the 12 I have tested in this design only one boosted, the rest did not boost at all, got distortion but no real signal boost.
Longevity, Tubes are rated @ hours of life based on expected use. So at a heater voltage with a given plate voltage the tube should get to a specific temperature. In this design with Plate voltage so low, I believe, but could be wrong, the heaters will die before the tube does. I have killed tubes with this design, mostly 12u7 and 12ae7 using 30 volts on the plates.. but that is another issue. :)
I havent killed any tubes yet and its been a couple years now i believe. Some 12ax7 have more resistance than others and thats why some work better than others. 12au7 has much less resistance and thats why they work better in starved plate designs. above 24v I have had better and more consistent results with 12ax7 but I think they sound best at over 100v most of the time. 12au7 acyualy sounds great to me at 9 or 12 volts in this design. Just an opinion, and we know what they say about those :icon_wink:
Hi there, new guy coming very late to the party. I have a question for you guys that I can't seem to find an answer for anywhere else.
I have a load of 18650, 3.7 Volt 2400 mA/hr Lithium ion recheargeable batteries lying around, that I use for flashlights. Three in series would give 11.1 Volts. Is there any reason why using these to power my Valvecaster would be a BAD idea? I still like the original idea of the Valvecaster being wall wart free.
I don't see a reason, the load should should be about 160ma +/- 10% with heaters. the 11.1 is a little low, but will work for the heaters.
it will work fine. it will just drain them fast. at least i think it will.
I've found a solution to the compression/sagging problem I've been experiencing with the Twincaster & thought I'd share it in case it's of any help.
This is a standard build using NOS Phillips JAN 12au7's which both work very well in a single valvecaster. I've added a switch to change between 2 values of C1 as my amp is rather heavy on bass.
The solution was found by changing 2 things.
1. C2a & C2b were changed to 63v 47nf radial caps - the original wimpy ceramics were the right value but resulted in a total cut out of the signal when I hit a chord. (the signal returned after a second or so)
The bigger caps nearly cured the problem - I was left with a drop in volume at the start of the power chord. so..
2. insert a 22k resistor between pin 3a and the center lug of Gain 1 - this completely cured the issue though I might have achieved the same result with a different value pot. This was just easier.
thanks to everyone who helped me on this
difficult to see the resistor on the gut shot but here goes. Caps C2a&b are mounted on the top of posts in the vero to simpify changing them.
(http://www.stallibrass.com/images/twinCasterGutShotlab.jpg)
Quote from: stallik on November 15, 2011, 03:20:06 PM
2. insert a 22k resistor between pin 3a and the center lug of Gain 1 - this completely cured the issue though I might have achieved the same result with a different value pot. This was just easier.
Is this the same as turning the gain down, right? Gain at full grounds the pin, so you're adding 22k at full gain, so it should be similar to half-gain without the resistor. (If I'm looking at this correctly... big "if")
CHAD
I really thought that it was the same. My logic was that putting a 22k resistor in series with a 47k pot would change the range from 0 - 47k to 22 - 69k. YET, the pot turned down (to about half) did not give the same result as full up with the extra resistor in, even though the values would be the same.
The more I think I know about this new fangled electrickery thing, the less I really do.....
that would make it adjust between 69k and 22k. it never really gets to zero resistance to ground. not turning the gain all the way up cures the compression no matter how you look at it, If you use smaller caps on the input and between stages it help with the compression a bit as well. .002uf works good all the way around if your making twins or triples. putting them on switches to choose between fat and skinny is nice but i usualy just find a good setting and leave it so the switch isnt really all that. my opinion anyway.. :icon_smile:
Took the pot out and measured the resistance. it went from 16k to 0k! it is marked as a 47k pot! that explains why I was getting the difference. Replaced the pot but decided to leave a resistor in anyway to prent me turning the gain full up as I realy don't like the compression. Understand your reasoning regarding the switching input cap but in my case I'm using a tele that's light on base and a strat with a humbucker that's rather heavier. This gives me the chance to tune it for both guitars
Hi!
Did anyone put this thing already into Eagle for creating PCBs?
CU
Does anyone know if a russian 6H16б (6N16b) sub mini tube would be usable for a valvecaster (with the 100V mentioned in the data sheet I think)?
There's a guy on ebay who sell these.
The sub mini 1SH17b & 1SH24 are power amp tubes, aren't they?
Edit: found a thread for this tube :D http://www.diystompboxes.com/smfforum/index.php?topic=83164.0
Quote from: tuckster on November 28, 2011, 03:53:00 AM
Does anyone know if a russian 6H16б (6N16b) sub mini tube would be usable for a valvecaster (with the 100V mentioned in the data sheet I think)?
There's a guy on ebay who sell these.
The sub mini 1SH17b & 1SH24 are power amp tubes, aren't they?
Edit: found a thread for this tube :D http://www.diystompboxes.com/smfforum/index.php?topic=83164.0
search subcaster, http://www.diystompboxes.com/smfforum/index.php?topic=63479.80
as to if they work.. @ 1.50 on ebay with shipping.. Who know but they are cheap.. may make a good SuperFly
I built this last night. Normal original schem provided by Dano: 12AU7, 9vdc supply. Started tweaking a little. I think my PS was only supplying 150mA, which is probably why it couldn't quite reach unity gain. I'll be addressing that shortly. ;)
My question is: Is anyone getting a bit of static sounding "wool" when turning the gain knob? Yes, this is a very simple circuit, but I was hoping I could clear that up. Of course, it was late and I didn't measure voltage from pin 3 to ground. Still, this crackle is not okay...
I picked up a 9AU7 to try tonight. ;D
Good for the 9AU7, altough it won't give you huge differences...I used one in the past just for fun.
yeah the scratchy pot is intended in this ckt, it comes from varyng the value of the resistance at the cathode...
Okay, thanks Adriano. That answered my question.
Quote from: Renegadrian on November 28, 2011, 12:50:33 PM
Good for the 9AU7, altough it won't give you huge differences...I used one in the past just for fun.
yeah the scratchy pot is intended in this ckt, it comes from varyng the value of the resistance at the cathode...
I think someone should try a parallel capacitor....
100pf probably?I boxed upped mine so too late!
could someone try that please?
I suppose I could do that. See you later tonight... ;D
(Y'know tasos, it would be super easy to just put a socket on the gain lugs...)
Quote from: ayayay! on November 28, 2011, 12:00:31 PM
I built this last night. Normal original schem provided by Dano: 12AU7, 9vdc supply. Started tweaking a little. I think my PS was only supplying 150mA, which is probably why it couldn't quite reach unity gain. I'll be addressing that shortly. ;)
My question is: Is anyone getting a bit of static sounding "wool" when turning the gain knob? Yes, this is a very simple circuit, but I was hoping I could clear that up. Of course, it was late and I didn't measure voltage from pin 3 to ground. Still, this crackle is not okay...
I picked up a 9AU7 to try tonight. ;D
A parallel Cap would not eliminate DC on the pot so that may not work, and depending on the value would change tone.
you can change the design to get ride of the DC noise on the pot, if you Bias the cathode with between 2 - 10K (inplace of VR1) , and place the pot between the tirode stages after the cap, so replace R4 with a 500K audio pot
I would go to 12V..but that limits battery use unless you go to 18V
Cool, thanks Steve!
Quote from: iccaros on November 28, 2011, 01:25:29 PM
you can change the design to get ride of the DC noise on the pot, if you Bias the cathode with between 2 - 10K (inplace of VR1) , and place the pot between the tirode stages after the cap, so replace R4 with a 500K audio pot
+1 on that, so I introduce you to the
Valvemaster:
(http://dl.dropbox.com/u/967492/Valve%20Master.JPG)
- interstage gain pot - no more crackle - like a 'real' tube circuit. ;)
- proper cathode biasing of both triodes - like a 'real' tube circuit. ;)
Would be worth playing around with the values of R2 and R3, as well as the (nominal) 1K and 10uF cathode biasing. Quite why it's taken 131 pages to get rid of the crackle and get some proper biasing...... :D
Great post!
I've been doing this for a while on my starved plate fender/marshall style builds. I haven't read the thread in about 30 pages so I assumed it had been covered by now. I should check it more often.
I'd put 500k or 1M as the interstage volume. Also it would be nice to swap the "regular" but pretty useless tone control with a princeton-like tone...I have to try!!!
also I'd swap the input cap with a 22k-33k res. (after the 1M to ground) as in a tube amp (no cap, yes resistor)
Go back a few pages Rick, something very similar ;)
Last one I built looked something like this (http://juansolo.demon.co.uk/stompage/schematics/Valve%20Casters/BoobTubeSchematicV2.jpg)
(http://juansolo.demon.co.uk/stompage/images/boobtube3-o.jpg)
(http://juansolo.demon.co.uk/stompage/images/boobtube3-i.jpg)
i think the input cap is required because without it you get grid conducting and it makes crackly dc volume pot on your guitar. It also tames a little bass which is nice cause starved plate tubes tend to sound a bit farty sometimes. I have been building normal amps mostly now, but i still mess with starved plate tube preamps to see if I can make that "magic" low voltage one. Results are just ok so far in the high gain dept.
Hi guys!
I just tried to put the valvecaster in Eagle. In the next days, I will try to make a PCB out of this. As I am new to this, it will take me days... So it would be great, if you could check the schematic first.
I wanted to save money and space - so I exchanged the first stage of the twincaster with an opamp. The second half of the opamp is used for an output buffer.
I also put the footswitch (3pdt) and the LED on the schematic - just for having it complete... Not sure, if I will put them also on the PCB.
In addition, I added the charge pump. So I can switch between 12 V and apprx. 40 V.
Some of the resistors I put as trimmers, so I can adjust the value for tuning later, without soldering too much.
Again: It would be great, if some of you can check it... It will be time consuming for me to design the PCB and expensive to print...
Thanks!!
(http://dl.dropbox.com/u/18538681/Images/valvecaster_boosted.PNG)
its looks ok.. I would put 2m resistors on my first op-amp input.. but that is me..
are those Zener's in your voltage multiplier?
Thanks for checking!
I agree, it should be 1 or 2 M resistors at the input..
And yes, I once heard that Zeners are more effective than normal ones in the charge pump... Not sure, if this is correct.
I started yesterday with the PCB - is there anything, I should look at? I think, its the most important thing, to keep the length of the signal path short?!?
Anything else?
Thanks again!
Quote from: Dongle on November 30, 2011, 08:27:22 AM
And yes, I once heard that Zeners are more effective than normal ones in the charge pump... Not sure, if this is correct.
Geofex:
"1N400x diodes work and are cheap, but the losses are higher than they really need to be. For higher performance and lower losses, it's better to use something like the 1N5817 schottky diodes for low losses. But both will work." http://www.geofex.com/circuits/+9_to_33.htm
Gentlemen...sorry to jump in late, but we have indeed had the 'interstage pot like a tube amp' discussion before, in the postings regarding Adriano's 'Tube Star'. In fact, he made two or three different layouts with the gain pot implemented different ways. Larry S.
Yeah Larry, thx for reminding that and for all the support! :icon_wink:
Quote from: frequencycentral on November 30, 2011, 09:00:15 AM
Quote from: Dongle on November 30, 2011, 08:27:22 AM
And yes, I once heard that Zeners are more effective than normal ones in the charge pump... Not sure, if this is correct.
Geofex: "1N400x diodes work and are cheap, but the losses are higher than they really need to be. For higher performance and lower losses, it's better to use something like the 1N5817 schottky diodes for low losses. But both will work." http://www.geofex.com/circuits/+9_to_33.htm
I was looking for that quote. Since Zeners are made to allow voltage to flow backward (know.. bad wording I am tired) I think that they could be a problem once you hit a stage that exceeds the reverse turn on voltage, not sure if that would happen here but I would think about it. Schottky diodes drop less voltage so when you do the math on the stages you have 2x voltage - diodes, so you end up with a higher voltage with the Schottky
The rest is fine, Tubes make simple designs, its why they are popular, and we sell the some tone dripping dream to kids learning guitar :icon_lol:
Right... I got mixed up here. So it should not be Zener diodes but Schottky...
Anyway, before I destroy something or make it wrong, I will just place the same there as in my last charge pump... I think, they were probably also Schottky...
Yes, just checked! It was the 1N5817!
Btw.: What do you think about the use of the opamp as gain control? Its maybe not so "pure" anymore - but it should sound? And work?
Quote from: Dongle on November 30, 2011, 10:37:17 AM
Right... I got mixed up here. So it should not be Zener diodes but Schottky...
Anyway, before I destroy something or make it wrong, I will just place the same there as in my last charge pump... I think, they were probably also Schottky...
Yes, just checked! It was the 1N5817!
Btw.: What do you think about the use of the opamp as gain control? Its maybe not so "pure" anymore - but it should sound? And work?
Go ahead. A lot of tube pedals do this. Check out the Shakatube.
Quote from: Bill Mountain on November 30, 2011, 12:36:19 PM
Quote from: Dongle on November 30, 2011, 10:37:17 AM
Right... I got mixed up here. So it should not be Zener diodes but Schottky...
Anyway, before I destroy something or make it wrong, I will just place the same there as in my last charge pump... I think, they were probably also Schottky...
Yes, just checked! It was the 1N5817!
Btw.: What do you think about the use of the opamp as gain control? Its maybe not so "pure" anymore - but it should sound? And work?
Go ahead. A lot of tube pedals do this. Check out the Shakatube.
just to add, I think the opamp as a gain control is better than a pot on the cathode.
, and not re-bias the tube as the original is doing, better is the pot between stages as that is more like a "Tube" amp.
If you plan this on going to a tubeamp or even another pedal you may want some adjustment on the output, I have found that my Valvecaster overloads a unity gain opamp on the output, but then I do have a 6au6 added to mine :icon_mrgreen:
Quote from: iccaros on November 30, 2011, 12:48:09 PM
just to add, I think the opamp as a gain control is better than a pot on the cathode.
, and not re-bias the tube as the original is doing, better is the pot between stages as that is more like a "Tube" amp.
If you plan this on going to a tubeamp or even another pedal you may want some adjustment on the output, I have found that my Valvecaster overloads a unity gain opamp on the output, but then I do have a 6au6 added to mine :icon_mrgreen:
Thanks -I dont completely get this...
I am going to a tube amp - but thats why I piut the buffer at the end. Does this not help?
And what does "re-bias" mean? What should I change here?
QuoteAnd what does "re-bias" mean? What should I change here? [\quote]
The original design created distortion buy changing the bias adjustment on the cathode of the first stage. I think its better to A) control gain with a opamp before the first stage, or B) add a pot between the stages and adjust the "gain" or C) A&B
QuoteI am going to a tube amp - but thats why I piut the buffer at the end. Does this not help?
yes, it helps get a consistent signal and loading for the pedal.
Going strait to a tube amp should not need the buffer, and if you raise the gain a lot, you will start over-driving your preamp stage sooner, AKA tubescreamer
if you have a pedal after you may need the buffer as the gain from this pedal may be too much for the following on pedal.
So I am suggesting that if you have a opamp at the output of the pedal, give your self some way to adjust its gain, so that you may add more or less boost, or control the input from the tube to the opamp to not cause it to overdrive.
If
Alright!
I got it!
Thanks again! I will than go for A and B - and adjust the buffer also with a trimpoti...
Interesting article about triodes at low voltages:
http://www.freewebs.com/valvewizard2/Triodes_at_low_voltages_Blencowe.pdf
Quote from: thereminator on December 01, 2011, 06:11:26 AM
Interesting article about triodes at low voltages:
http://www.freewebs.com/valvewizard2/Triodes_at_low_voltages_Blencowe.pdf
That really is a good read. Nice.
http://www.diystompboxes.com/smfforum/index.php?topic=91745.0 (http://www.diystompboxes.com/smfforum/index.php?topic=91745.0)
This was my take on low voltage with a pentode out..
Hi!
I have been lurking for a while and this is my first post here. The Valvecaster is my second build in total and my first scratch build and I got it working on the first try. I like the sound in general but I thought it would be fun to add a charge pump to see what would happen. I have built the perfboard design by Rick Holt and it gives just under 80v unloaded: http://www.diystompboxes.com/smfforum/index.php?topic=74729.0 (http://www.diystompboxes.com/smfforum/index.php?topic=74729.0)
The charge pump works fine but I am not sure about how to hook it up to drive the plates. Here's my idea on how it should be done:
(http://i.imgur.com/hokhf.png)
Can you guys let me know if I'm on the right track here? Also, do I need to change the values of R2 (220K) and R3 (100K)? Anything else that needs to be changed?
Regards,
Stefan
^^^
You're hookup is correct. I'd be interested to see what voltages you read at the anodes though, as in my experience grounded cathodes make for low voltage at the anodes no matter how much you pump into them. I refer you to the Valvemaster on the previous page for a circuit more suited to 80v.
Thank you Rick. It worked beautifully. The voltage across the anodes is ~50v with this setup.
At first i noticed some weird noises and I then discovered that the old 12at7 I have been using had gone microphonic. This was with a tube that I had replaced in an amp some time ago. It has worked in my valvecaster until now but I think the voltage increase pushed it over the edge. I replaced it with a new 12au7 and now it works perfectly.
This is fun. I think I will have to put the Valvemaster on my build list.
Regards,
Stefan
Hi!
I read somewhere that for this pedal, if we power it with 12v, instead of 9v, it would be better for the valves. Is this true?
Sorry if this is something already discussed, but I couldn't almost anything using the search.
Regards ;)
Quote from: norim_13 on December 15, 2011, 06:08:17 PM
Hi!
I read somewhere that for this pedal, if we power it with 12v, instead of 9v, it would be better for the valves. Is this true?
Sorry if this is something already discussed, but I couldn't almost anything using the search.
Regards ;)
The heaters wired for 12v ran on 9v is fine, there was talk it could hurt the tube.. I see no evidence of this as long as it is wired for 12V heaters (series)
Running at 12V gives more headroom.. 24 is better, 75V would be awesome..
Thanks ;)
For higher DC voltages, does the schematic change? Or can I just replace the 9v power supply with 12v?
BTW, does this affect the sound in anyway?
Regards
Quote from: norim_13 on December 15, 2011, 07:48:33 PM
Thanks ;)
For higher DC voltages, does the schematic change? Or can I just replace the 9v power supply with 12v?
BTW, does this affect the sound in anyway?
Regards
no changes for 12v, as for sound you get a little more volume, not much but for some tubes you also get more levels of dirty...
if you go above 12v you need to think about how to give the tube heaters only 12v.
Quote from: frequencycentral on November 28, 2011, 01:58:54 PM
Quote from: iccaros on November 28, 2011, 01:25:29 PM
you can change the design to get ride of the DC noise on the pot, if you Bias the cathode with between 2 - 10K (inplace of VR1) , and place the pot between the tirode stages after the cap, so replace R4 with a 500K audio pot
+1 on that, so I introduce you to the Valvemaster:
(http://dl.dropbox.com/u/967492/Valve%20Master.JPG)
- interstage gain pot - no more crackle - like a 'real' tube circuit. ;)
- proper cathode biasing of both triodes - like a 'real' tube circuit. ;)
Would be worth playing around with the values of R2 and R3, as well as the (nominal) 1K and 10uF cathode biasing. Quite why it's taken 131 pages to get rid of the crackle and get some proper biasing...... :D
Hi!
I have a question for this layout:
The 10uF at the cathode... this is a highpass to ground, right? So for all frequencies above a certain threshold, there is no resistance... And as 10uF is a quite high value, there is basically no resistance for the interesting frequencies?!? Did I get something wrong here?
10uf is standard in most HIFI designs.. you can change it to what you like..
edit..
10uf will pass almost all audio for a guitar or bass. if you want to start bypassing go lower
for a 10u with 1K at 100K load you get about this.. you can do the math to see if the graph is correct.
(http://dl.dropbox.com/u/14312589/10uf%201K%20responce.png)
Hey, does anyone know if the sockets over on Small Bear are PCB mount or if they're solder lugs?
forgive me if this has been asked, but has anyone tried a 12AT7 or 12AY7 in a valvecaster?
Quote from: runmikeyrun on December 19, 2011, 01:48:44 AM
forgive me if this has been asked, but has anyone tried a 12AT7 or 12AY7 in a valvecaster?
I've tried a Ruby AT7 and it worked just fine. Infact, it was my favorite unilt I got some NOS AU7's. I used mine for bass and would roll of the lows at about 70Hz to keep from getting hardcore blocking distortion.
There have been both pro and con opinion regarding higher-gain tubes in the stock valvecaster...some folks like them, others don't. My 2 cents says, if you're going to the trouble of building a box for a higher-gain tube, use a supply that puts higher voltage on the plates. Larry
Quote from: runmikeyrun on December 19, 2011, 01:48:44 AM
forgive me if this has been asked, but has anyone tried a 12AT7 or 12AY7 in a valvecaster?
my experience.. Standard valve caster 12v
12ax7 no real gain.. ok.. but no boost..
12au7 good boost, when gain maxed really farts out.
12u7 -- good sounding, mod gain, no difference adding more voltage.
12at7 -- more distortion (good in my eyes)
ECC99 .. my GOD... best sounding for me.. Good distortion, turn down to "warm" overdrive.. lots of boost, would not turn master volume past 1/4
5751 -- Good sounding low boost, nice warm overdrive but bad when gain turned more than 75%
@24v
12ax7 -- useable, more boost.. but still lower boost than the rest --- accadently broke the glass, these JJ's seem touchy
12au7 -- more headroom (more clean before distortion)
12u7 -- no change..
12at7 -- Full on Distortion pedal, with good gain, my NOS at7 had noise, so while I loved the tone, did not like the whine
ECC99... if it was not so big and get so hot (pulls more 400ma for heaters) this would be what I would use.. with the heat of the tube and voltage regulator for heaters this pedal got hot.. just a note
5751 -- good sounding, good boost.. nice warm overdrive but bad when gain turned more than 75%
I also use the Russian (like most new tubes are not made there) needed to adapt for 6.3 on heaters so more heat from the voltage regulator..
6N6P --- same as ECC99 but less costly, more heater current.
6N2P -- close to the 5751.. a little better sounding but I believe my 5751 is going micro-phonic..
as for more voltage..
you can add more voltage and get more clean.. you may have to watch output voltage as the swing gets bigger, into a tube amp is really no big deal but a poorly created SS amp would have issues.
if more clean is not what you want, then an AT7 really created a good distortion in my case, too bad I like it in my Firefly better.. Ricks drawing above is a better way to make this pedal.. Add a voltage mutiplyer and you are in even better shape, for more clean and slamming a tube amp into full distortion.
I started work on a *yipes* quadcaster tonight. I used two twincaster vero layouts next to each other. I am building it for bass, so I am socketing the input and coupling caps along with the anode and cathode resistors. I'm going to try the stock valvecaster values first, then try the valvemaster values and see which sounds better. I am making a couple of mods- I am using a 500k gain pot in between the first and second gain stages instead of the standard 50k pots on the cathodes. I'm also considering making a switchable JFET buffer stage at the input because I have an active bass, but honestly I don't even think I need it.
I ordered (3) JJ 12AU7s and (1) JJ 12AT7. I will be using this on bass and I really like the way JJs sound in my bass amp. I might try the 12AT7 in V1 to see what happens, I really want to go for higher gain.
I am taking photos and will post a build report when finished just in case anyone wants to build one. I'll also work on sound clips. Eight gain stages.... even though they're not high gain tubes it should still be fun!
Quote from: runmikeyrun on December 19, 2011, 09:47:24 PM
I started work on a *yipes* quadcaster tonight. I used two twincaster vero layouts next to each other. I am building it for bass, so I am socketing the input and coupling caps along with the anode and cathode resistors. I'm going to try the stock valvecaster values first, then try the valvemaster values and see which sounds better. I am making a couple of mods- I am using a 500k gain pot in between the first and second gain stages instead of the standard 50k pots on the cathodes. I'm also considering making a switchable JFET buffer stage at the input because I have an active bass, but honestly I don't even think I need it.
I ordered (3) JJ 12AU7s and (1) JJ 12AT7. I will be using this on bass and I really like the way JJs sound in my bass amp. I might try the 12AT7 in V1 to see what happens, I really want to go for higher gain.
I am taking photos and will post a build report when finished just in case anyone wants to build one. I'll also work on sound clips. Eight gain stages.... even though they're not high gain tubes it should still be fun!
that is a lot.. Like to see if you get any clean after that..
I also like using a small pentode after the single valve caster..
Its not a bass but you get lots of gain -->
that's awesome! I would love to do something like that but i'm being lazy and don't want to do HV... I like the simplicity of the LV circuit. Besides i'm trying to finish a tube amp project and that's giving me enough potential to get electrocuted
that is 12v... no HV... look up lonewolf for the pentode part.. I posted a project that put a different valve caster with the lonewolf, I uses a 6au6 and a 12ax7.. see a few pages before..
Oh great, now I have to build ANOTHER tube pedal after this one ;) Seriously, thanks for the info, I will check into it.
For my third pedal project, and apparently because I am a glutton for punishment, I breadboarded the ValveMaster up.
But because I have limited electronics experience, I made a few missteps (like, I suspect, interpreting the tube symbol as shorting pins 4 & 5 on the tube). Went over the circuit with a fine tooth comb, even going so far as to pull it and do it again. No parts subs except for the use of an ECC82 tube (which I'm lead to believe is a thin-plate variant of the 12AU7). I get no output and I don't see the tube light up (I'm not even sure that I should, frankly).
I think I must be interpreting the schematic incorrectly though. Just looking for confirmation of some of my assumptions and interpretations.
1. The ground of the input and output jacks connect to the ground rail?
2. VR1 pin 1 goes to C2, pin 2 to tube pin 7, pin 3 to ground?
3. VR2 pins 2 and 3 are soldered together and the result goes to ground?
4. Output jack comes off of pin 2 on VR3?
5. Power supply can be a simply 9VDC battery? Or do I have to use something with more current? If I use a 12VDC/1A supply, will I harm the circuit?
6. Tube pins 4 & 5 should not be shorted to each other?
7. 9VDC negative goes to the ground rail, right?
1. The ground of the input and output jacks connect to the ground rail? Yes
2. VR1 pin 1 goes to C2, pin 2 to tube pin 7, pin 3 to ground? Other was round: 1 to ground, 2 to C2, 3 to pin 7
3. VR2 pins 2 and 3 are soldered together and the result goes to ground? Other way round: 1 and 2 soldered together and grounded, 3 to C4
4. Output jack comes off of pin 2 on VR3? Yup
5. Power supply can be a simply 9VDC battery? Or do I have to use something with more current? If I use a 12VDC/1A supply, will I harm the circuit? A battery won't last long at all. 12VDC/1A is fine - observe correct polarity
6. Tube pins 4 & 5 should not be shorted to each other? They should not be shorted together. Pin 4 to ground, pin 5 to +ve
7. 9VDC negative goes to the ground rail, right? Yup
Thanks for that.
The pots were the wrong way around, but my understanding is only that the should work in the wrong direction, not that the circuit won't work at all, right?
Should I actually be seeing the tube light up?
Cheers,
Quote from: Yeahno on December 22, 2011, 02:27:59 PM
Should I actually be seeing the tube light up?
Yes there should be a subtle orange glow, it's not a light bulb, so you may have to look for it. Are you sure you are reading the pinout the right way around?
I think it would be prudent to check it again. My reference is http://www.dogstar.dantimax.dk/tubestuf/pinout.htm
Wondering if shorting pins 4 & 5 under power would have damaged the tube.
Pins are correct. But where should pin 9 be connected?
Leave pin 9 NC - if unsure of the tube, just have two wires coming off the wall wart (+ and grd) and connect them at pin 4 and 5 (direction doesn't matter) - make sure to count the pins in the right direction, sometimes I do it wrong myself still...with the pins facing you, the gap facing bottom, the pin at the left of the gap is pin 1, start counting CCW.
As Rick said, you should see some light from the heaters - every tube is different from the others, some have a nice glow and some are barely lit. but you should see 2 small orange points at least.
a 12V-1A is what I use and find great for these kind of ckts. I found some very cheap at the bay. (like 3$) and silent!
Thanks! Pin 9 will remain unconnected.
I can just barely see the heaters with 9VDC connected, but they're definitely there.
Clearly, I've mucked this up somewhere that isn't obvious to me.
just be patient, double check your work, if you get frustrated walk away and come back later. You'll get it working. Look on this thread for the voltage readings for each tube and check yours to see if you've got the correct voltages. Also make sure you've got the tube wired correctly- that you've got pin 1 connected to pin 1 and not pin 9, etc.
Incidentally, I tried a JJ 12AT7 yesterday in my valvecaster, it sounded really good! A decent amount of grit and more gain for sure.
Thanks for the encouragement.
I've checked the pin outs and matched them to http://www.dogstar.dantimax.dk/tubestuf/pinout.htm, which I take to be correct. And I'm assuming that if the pins weren't correct, I wouldn't be seeing the heaters light up as I do now.
I'm building a ValveMaster, which appears to put VR1 in a completely different place than the ValveCaster. I'm thinking that perhaps building the ValveCaster would be prudent.
When I've checked everything a couple of times, I simply walk away and plug in the MultiFace or Tube Reamer and bang away for a while. It's an excellent way to clear out the cobwebs.
Cheers,
Quote from: Yeahno on December 23, 2011, 05:17:47 PM
Thanks for the encouragement.
I've checked the pin outs and matched them to http://www.dogstar.dantimax.dk/tubestuf/pinout.htm, which I take to be correct. And I'm assuming that if the pins weren't correct, I wouldn't be seeing the heaters light up as I do now.
I'm building a ValveMaster, which appears to put VR1 in a completely different place than the ValveCaster. I'm thinking that perhaps building the ValveCaster would be prudent.
When I've checked everything a couple of times, I simply walk away and plug in the MultiFace or Tube Reamer and bang away for a while. It's an excellent way to clear out the cobwebs.
Cheers,
can you list the voltages on all pins
also you can use a DMM to check your signal path, connect the guitar or put a signal. place it in AC mode, read the input.. should me millivolts (I see 300mv on mine) with a guitar connected.
check after the cap from the plate of the first stage to the grid of the second.. what do you read ? if you get signal check it at the output.. where you loose signal is where you are having issues..
Thanks for the schematics !
I´m an amateur but finally able to build my first TUBE-preamp(stompbox) :)
My experiences with first(original) schematic, and first stage changed smaller imput capacitor and 2.step with katode capacitor modification(now 100mikroF) on first catode only:
12V and lately 40V now is better
-ECC82(12AU7) Tungsram work ,but I think not too good overdrive sound, and too much cut in lows, and no sustain ( lost the sound)
-6N2P(Soviet Ecc83/12AX7) work, but similar overdrive problems otherhand I like the clean-lowgain sond (heater voltage 6V)
-E88CC Tungsram work, tryed only 12V yet similar like 6N2P most clean sound in lowgain
-ECC85 Tungsram Cool overdrive sound now is my favorite but already have alitle low cut and lost sustain
lately I will upload pictures and soundclips with ECC85
Merry Christmas
ECC85 is similiar to ECC81/12AT7, but it has heaters like in ECC88 or 6N2P.
So I just about have the quadcaster up and running... I need to hit the electronics store to pick up one trimpot and a couple sockets. I've audio probed it through the 7th gain stage and it sounds AWESOME on guitar and bass. No sag, no harsh high end, just warm creamy beautiful tube distortion. How much distortion you ask? Well, I'd put it somewhere between the Smash Drive and the Tufnel, but obviously does not sound like them. This is with all gain stages set at max gain and the gain control on 10. It does clean up nicely at lower gain settings. This thing produces amazingly thick crunch and sounds incred. I will try to finish it up in the next few days and get some sound clips, pics and possibly a video plus some notes on the few mods I did.
EDIT: forgot to mention- i'm using a 12AT7 in V1 for extra gain. I have a single valvy here and it sounds great in that and really kicks things up a couple notches in the quadcaster. If you like the tone of the valvy but want more gain try a JJ 12AT7, it sounds great.
I just built this on the breadboard. I didn't read all the posts in this thread but I read enough to get the drift: This is a "subtle" pedal. My breadboard test confirms that. Has everyone else had the same experience?
My quick eview: With a 9 volt battery that measured 8.9 v (that is all I had; will 9.36 volts really do much more than 8.9v? ) the effect was mild. All the knobs worked. The battery just barely gets the two main tube filaments to glow. It did seem to give my SS Crate practice amp somewhat of a tube tone and there did seem to be some boost and the mildest distortion. Nice rich tone. (or was I imagining it?) After about 15 minutes of playing it brought the battery down from 8.9 v to 8.03 v.
There were some questions about whether this pedal could be played with a 12 volt power supply but I didn't read enough to get to an answer. Has anyone tried this with a 12 volt power supply? How did it sound?
Can anyone direct me to any segments of these 133 pages that contain specifically interesting info, esp., like how to modify this design to run it at 12 volts and get more overdrive from it ? Thanks.
COME ON DON'T BE SO LAZY!!! :icon_evil:
YOU WANT INFORMATION, YOU GOT A LOT IT'S JUST UP TO YOU TO TAKE YOUR TIME AND READ...
a manual of condensed thread
http://www.aronnelson.com/DIYFiles/up/12AU7-6111_Valve_Caster_Summary_Rev002.pdf
check HUM and NOISE
a bread board layout of original circuit
http://www.beavisaudio.com/bboard/projects/ttb_Valvecaster.pdf
tube cricket
http://www.diystompboxes.com/smfforum/index.php?topic=63479.msg506164#msg506164
boobtube schem
http://juansolo.demon.co.uk/stompage/schematics/Valve%20Casters/BoobTubeSchematicV2.jpg
latest iteration the Valve-master:
http://www.diystompboxes.com/smfforum/index.php?topic=63479.msg819365#msg819365
high voltage
http://www.geofex.com/circuits/+9_to_33.htm
charge pump layout
http://www.diystompboxes.com/smfforum/index.php?topic=71381.msg607779#msg607779
Yes I've been reading .... I tried it with a 12 volt ac adapter. "Atrocious" hum is how someone who had the same result described it. I need a regulated power supply ... a LM 7812 voltage regulator but I can't find any info on installing one in a valvecaster to eliminate the noise when using 12 volts ....
A LM7812 on its datasheet shows how to connect it, but this works, replace the LED with the Valvecaster + and - connections.. (http://t1.gstatic.com/images?q=tbn:ANd9GcSe3Pm08ln1rdZit5KO4sFOYOEpGciQPnpnzGf85YnjFOMeC5d_)
. regulated power is not necessarily, you get hum from poor soldering joint or needing to filter your power, so a 10uf 20v on the power input, also do not wire heaters to your signal ground. The components are good up to there max voltage rating, except heaters on the tube which are good for 12.6 +/- 10%. so if you go above 13.5v you will need a resistor, zener or regulator to reduce voltage to the heaters
I am using a voltage booster, so I have 12v in with a filter cap across the input and heaters directly connected to the jack. I connect all signal grounds to the last cap in my voltage multiplier, not to same ground point as the heaters or the first ground connection on the multiplier.
Iccaros: Thanks for posting that. I looked closely at a few data sheets and found it. Didn't quite understand it till I read what you wrote.
Rotylee: Thanks for the manual of the condensed thread. Very helpful.
Hi Guys,
This is my valvecaster. After reading about a lot of problems with tone (dark sounding circuit), JJ tubes (not that good on 9v), and power supply's I was wondering if my valvecaster would do anything good. (I already ordered a JJ 12au7, and I've only got a 9v china switching power supply)
Luckily, when I tried my pedal yesterday I was surprised about how great it sounds! :)
I took out the tone circuit (I don't have any problems with full tone here), soldered it together, drilled an enclosure and played.
this is what it looks like:
(before painting)
(https://p.twimg.com/Ah1KD_ACQAAu71F.jpg:large)
and after painting:
(https://p.twimg.com/Ah147SJCAAAN28r.jpg:large)
and these are my sounds:
First sound = clean, second = gain 0, third = gain 1/3, fourth = gain 2/3, and last but not least, full gain!
somehow my MacBook mic decides to get nasty every once in a while, so the sound morphes a bit.... it's my mic, not the pedal (luckily!)
I really like the way this tube reacts to the loudness of my strumming. It just screams if you want it to! :)
next build will be a reverb, then a tubescreamer, and then I will throw away my boss me20
Nce! I got a Vester amp too (and a strat copy) - pity they made them close...
I like your valvy! Now go and buy a 12v wall wart, there are some on evilbay for cheap! 12v/1A
I had a behringer before... a big mistake. When I trashed it because it was a crappy amp which broke down about every five minutes, my neighbour (who also plays guitar) brought me this vester which he had lying around in the attic. he hadn't used it for years and didn't know if it still worked.
it did :)
I really love this tiny amp... it's one 10 in speaker provided with 30 watts, with amazing tone and the louder it gets, the bluesier.
I'll go and try a 12v soon, but now I've got this working I just want to play... a lot...
by the way. I've got a friend who's built a 2ch 12au7 phono preamp, and while I was trying to get this working, I asked him for advice. He has had the problem that whenever he put the valvecaster diagram on his breadboard, each time it sounded different? even while using the exact same components? weird stuff ???
Intresting pedal.. but after so many that seems to have build this pedal and almost no one have recorded anything, thats lame.. hahaha, i am sure ppl want to hear what this pedal sounds like, both the single tube and the double tube version.. :D, i belive this is not a high gain pedal...not easy to get high gain out of a tube distortion i belive..
I would concider building this pedal, if i know what it sounds like :D
Quote from: Perkla on December 31, 2011, 08:17:27 AM
Intresting pedal.. but after so many that seems to have build this pedal and almost no one have recorded anything, thats lame.. hahaha, i am sure ppl want to hear what this pedal sounds like, both the single tube and the double tube version.. :D, i belive this is not a high gain pedal...not easy to get high gain out of a tube distortion i belive..
I would concider building this pedal, if i know what it sounds like :D
There are plenty of vids on youtube.
Quote from: Bill Mountain on December 31, 2011, 09:14:20 AM
Quote from: Perkla on December 31, 2011, 08:17:27 AM
Intresting pedal.. but after so many that seems to have build this pedal and almost no one have recorded anything, thats lame.. hahaha, i am sure ppl want to hear what this pedal sounds like, both the single tube and the double tube version.. :D, i belive this is not a high gain pedal...not easy to get high gain out of a tube distortion i belive..
I would concider building this pedal, if i know what it sounds like :D
There are plenty of vids on youtube.
I have not seen very much homebuilt tube distortion pedals on youtube..
After all this tweaking and playing with this circuit, I really just like it pretty much in it's original form except for the tone control and the caps.
I've decided I like it with no tone control and a switchable cap to ground to de-brighten it. Leave that tone pot out of it. It also helps a LOT to just make C1 & C2 smaller to control bass. Keeps things from getting flabby. I'm pretty happy with a .01uF or .012uF for C1, .01uF for C2, and a 680K for R2 for more gain.
Makes it an ideal pedal at the end of the pedalboard as a gain and/or solo boost.
Quote from: Perkla on December 31, 2011, 09:31:53 AM
I have not seen very much homebuilt tube distortion pedals on youtube..
simple search...5 sec
http://www.google.com/search?sourceid=chrome&ie=UTF-8&q=youtube#q=valvecaster+site:youtube.com&sa=X&ei=rWX_ToCvC5HZiAKO__S7Dg&ved=0CFsQ2wE&hl=en&safe=off&bav=on.2,or.r_gc.r_pw.,cf.osb&fp=a07b3761d35d504a&biw=1920&bih=1075 (http://www.google.com/search?sourceid=chrome&ie=UTF-8&q=youtube#q=valvecaster+site:youtube.com&sa=X&ei=rWX_ToCvC5HZiAKO__S7Dg&ved=0CFsQ2wE&hl=en&safe=off&bav=on.2,or.r_gc.r_pw.,cf.osb&fp=a07b3761d35d504a&biw=1920&bih=1075)
I have a spare NOS Philips 12AU7 and I might try to assemble this. The only thing that blows my mind is the huge thread: 134 pages. I'm kind of lost in the 11th...
no glory without some suffering...come on, don't be lazy, read on and learn from every page...there's no shortcut!
(actually there is, but you didn't read this page neither!) SHAME ON YOU!!! :icon_evil:
JRM: There's a post at the top of this page with links to key sections of this thread. Good place to start.
page 134 and counting....wow :icon_eek: tubes are sweet. :D
Well I have been reading the tube pedal book here ... and I got the basic ( revision: 1.0 from 30 October 2008 from a beavis audio research breadboard layout) Valvecaster working on a breadboard. The more I play it the more I like it. But I see from this material that there are "improved" Valvecasters and a valvemaster and other versions of this tube pedal.
So the question is: Which of these versions will sound best when run on 12 volts? Can one power a revision 1.0 Valvecaster with a regulated power supply made with a IC 7812 and improve its sound?
What effect would using a B50k pot for the tone pot have on the sound of the pedal?
Thanks.
Well...
Now that I'm on the other side of the new year, I spent some time hammering that flat spot on my forehead even flatter...
...and got the Valvecaster working on a breadboard. 12v really is the minimum for the Valvecaster to sound like anything, so the thread title itself is...well...unhelpful. Sure, you can drive a 12AU7 on 9v. But you don't want to.
So, having only read about 2/3rds of the 134 pages (and counting) of the thread, I didn't catch how subtle the effects of this pedal are. It's really, really subtle. It's there, certainly, but I can barely get it to break up with the volume & gain dimed. I'm not looking for "metal"...just a reliable, crunchy breakup off my Tele when I hit the strings harder. I'm not sure that this is the pedal for me yet.
I've read that some folks like putting a boost in front of it (or even building a boost into the thing) and that makes the pedal break up in what sounds like the way I'm looking for. But I'm also stuck on the appeal of the all-tube aspects of this thing.
So now I'm wondering if the thing to do isn't simply to build a Twincaster.
Thoughts?
Well, my thought on this issue is that I dont care about the design of anything - as long as it sound sgreat.
And if you like the sound of an IC before the pedal, why dont you go for it? An all-tube-approach does not help you, if you dont play it because it does not sound as good.
In addition: I think even the hardcore tubers agree, that a buffer behind the tube is needed. The buffer also has an IC... So why not put anotherone in front of the pedal to boost?
And by the way: ICs are still analogue.... so you still would have an "analogue, hand wired tube pedal"...
Disagree! ;D (you could also have a tube buffer if you really want...)
Alright... You can also rectify the ac-current with tube-diodes. But make sure, the whole chain from the powerplant to your pedal uses tubes ;) (Sorry, just joking - I know the difference)
Did you try the tube buffer? Sounds interesting...
Actually, I always really wanted to build a tube screamer (TS808) with a tube based Op-amp... But its still to complicated for me.
Still, I think the buffer behind my valvecaster enhanced the sound, although there is an "evil" IC in the circuit.
you could use another AU7, one triode for buffer and one triode for MORE boost. switchable or fixed.
Forgive my newby-ness...
So tube buffer before tube would be the Twincaster? And the IC before tube would be Adrian's Valvy circuit?
Spent a bunch of time on Youtube trying to find Twincaster clips. Lots of Valvecaster stuff, mind you.
Quote from: Rick899 on January 04, 2012, 01:05:00 AM
Well I have been reading the tube pedal book here ... and I got the basic ( revision: 1.0 from 30 October 2008 from a beavis audio research breadboard layout) Valvecaster working on a breadboard. The more I play it the more I like it. But I see from this material that there are "improved" Valvecasters and a valvemaster and other versions of this tube pedal.
So the question is: Which of these versions will sound best when run on 12 volts? Can one power a revision 1.0 Valvecaster with a regulated power supply made with a IC 7812 and improve its sound?
What effect would using a B50k pot for the tone pot have on the sound of the pedal?
Thanks.
this is a hard question to answer, you see this is a starved plate design, and way out of the Linear operation of the tubes we are using. IF you had a 12u7 (hard to find) which is a 12v tube than this would be easier to answer as we could draw a good load line, but we can not tell you if it sounds better, that is up to you. The only way to know is try, I find it interesting that even the same tube type (12au7 for example) from the same manufacture can sound different
Hi guys! i'm new of the forum and i'm italian so prepare yourself to a lot of errors from me ;)
I built the basic valvecaster, VOL GAIN TONE with an ECC82 JJ and the standard components on page 1...
It works fine in bypass... no rumors ecc ecc and the signal pass all!!
It runs on 9V, the tube lights on, also does led but, when i run the pedal, it low a lot volume even at maximum of VOL and GAIN...
i checked lot of times che circuit and it fits the shematic..
What could i do??
thanks!!!
@Yeahno
Twincaster as the name implies is just a valvy x2 (in series)
It could be a starting point for experiments to add to the classic valvy schem another double triode, one for another boost stage and one for buffer (in or out) - that is not related to my valvy layout (which is almost standard, just the tone removed) and based on original dano's schem.
basically using a cathode follower you have gain=1 and buffer.
mandatory reading = http://www.freewebs.com/valvewizard/accf.html
Teo, please give more information or...scrivimi in pvt se serve ok?!
QuoteTwincaster as the name implies is just a valvy x2 (in series)
It could be a starting point for experiments to add to the classic valvy schem another double triode, one for another boost stage and one for buffer (in or out) - that is not related to my valvy layout (which is almost standard, just the tone removed) and based on original dano's schem.
basically using a cathode follower you have gain=1 and buffer.
mandatory reading = http://www.freewebs.com/valvewizard/accf.html
Heh. The Valvecaster on the breadboard has just become a Valvemaster. The sound is growing on me.
Adrian: Thanks for the tips and the link. I'm going to wade through the tube stuff. Perhaps some of it will rub off.
Cheers,
I used this scheme http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=39952&g2_serialNumber=2 to make the valvecaster standard...
I did the circuit well, checked 3 times...
Bypass mode it's ok, no volume decrease, no rumors...
Attive mode, even with VOL knob at maximum, i have maximum half volume then bypass mode... GAIN and TONE knobs works correctly, i can hear them... but volume goes to 0% to 50% of the bypass mode...
Can you find something wrong in the wiring diagram? wrong components??
I have used carbon resistence, 100k/470k/220k/1M/400 ohm (for blue led)
I have used polyestere capacitors 47n/47nf/10nf/ and 1 electrolitic polarized 1mf
3 POTS 100k 100k 50k
3PDT footsw
And i run it on a brick 9V 1Ampere
can you post tube voltage.
also what I find helpful, if you can insert a signal (play the guitar) and give us the AC voltages, while playing, on pin 2, pin 1, pin 6 and pin 7
thanks
Here is the datasheet http://drtube.com/datasheets/ecc82-jj2003.pdf
AC voltages with tester are:
PIN1 12V
PIN2 0V
PIN6 14,8V
PIN7 0V
those are DC right? if those are AC, we have big issues.
what is your power source?
nope... reported AC as you asked me.. set tester on 200V AC to take measurements.
i use a BESPECO PS-50 1 Ampere 5 exit on 9V
PPS:
I tested also DC and i got:
PIN1 6.86V
PIN2 -0.01V
PIN6 7.74V
PIN7 -0.12V
what is the DC voltage read directly from the power supply, what is your DC on each pin? are you using a voltage booster? 200vac range is too large, do you have a 10 or 20v range?
you should see about 100 - 300mv ac from the guitar coming to pin 2, this should give a swing of about 1vac to the next stage (from pin 1 over the cap to pin 7)
Pin 6 output should not swing higher than 1.5 - 3 volts I would think.
in comparing your DC to AC, something is wrong with the AC readings, as there is no way you can have a larger AC swing than DC in this design, unless your power supply is putting out AC..
PowerSupply send 9V stabilized DC. i can read about 18V AC on the same jack of tha daisy chain... I tested with the tester in DC and it send about 9.14V
I'm not using any voltage booster, just plugging the power to the http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=39952&g2_serialNumber=2 scheme!
My tester only has 750/200 V AC scale and 200m 2000m 20v 200v 1000V DC scale
Quote from: Teo87 on January 04, 2012, 05:09:05 PM
PowerSupply send 9V stabilized DC. i can read about 18V AC on the same jack of tha daisy chain... I tested with the tester in DC and it send about 9.14V
I'm not using any voltage booster, just plugging the power to the http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=39952&g2_serialNumber=2 scheme!
My tester only has 750/200 V AC scale and 200m 2000m 20v 200v 1000V DC scale
there is your issue, that power supply is putting out way too much ac, its crushing the little signals from your guitar and from the tube. I would suggest using another power supply, use a different position on the supply, and testing, use a 9v battery if you can, this will tell you if the rest is correct.
The DC voltages look good, or at least OK.. you do have 9v between pin 4 and 5?
I found an 11 page document online titled "12AU7 Valvecaster". On page 4 of that article is a schematice of a "Dual Valve Caster" and below that is a vero board layout by Renegadrian of the Twincaster.
Is the Dual Valvecaster the same pedal as the Twincaster? I am a novice at all this and am confused by the Dual Valvecaster schematic which has two R1, two R2, etc. Should the tubes be V1A+V1B and V2A+V2B? If I were to build the Dual Valvecaster from the schematic, how do you deal with two of each component? For example if there are two R1 resistors should they be treated as R1a and R1b in order to precisely distinguish between the two and the specific location in the circuit where they go?
The dual has 14 caps and resistors and the Twin has two of most of the components (labeled for example 2a and 2b) for a total of 11, so they seem to be different.
Is there a schematic of the Twincaster available to forum members ? I haven't been able to find one. But I have seen the layout numerous times.
I am still debating over which pedal to build .... the Valvecaster (which as I have said I already have working on the breadboard), the Valvemaster, the Dual Valvecaster, or the Twincaster. Which pedal will work best on 12 volts? Which will be the quietest and have the greatest range in terms of boost and of clean to distortion? I have all the parts I need including some NOS RCA and Sylvania 12 ax7 and 12 au7 tubes and am itching to get started. PLease answer my questions and help me decide. Thanks.
8.90V between pin 4 and pin 5
I'll try with a 9V battery then i'll repost you...
Quote from: iccaros on January 04, 2012, 05:34:56 PM
Quote from: Teo87 on January 04, 2012, 05:09:05 PM
PowerSupply send 9V stabilized DC. i can read about 18V AC on the same jack of tha daisy chain... I tested with the tester in DC and it send about 9.14V
I'm not using any voltage booster, just plugging the power to the http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=39952&g2_serialNumber=2 scheme!
My tester only has 750/200 V AC scale and 200m 2000m 20v 200v 1000V DC scale
there is your issue, that power supply is putting out way too much ac, its crushing the little signals from your guitar and from the tube. I would suggest using another power supply, use a different position on the supply, and testing, use a 9v battery if you can, this will tell you if the rest is correct.
The DC voltages look good, or at least OK.. you do have 9v between pin 4 and 5?
yep 9V between pin 4 and pin 5... 8.94 exactly!
Tomorrow i'll try with a 9V battery
Quote from: Yeahno on January 04, 2012, 04:04:55 PM
Heh. The Valvecaster on the breadboard has just become a Valvemaster. The sound is growing on me.
I'd be interested in your opinion re any differences/advantages of either varient.
QuoteI'd be interested in your opinion re any differences/advantages of either varient.
I'm afraid I can only speak to the perceived differences. I'm going to leave the engineering aspects of it to the people here who are qualified to make such judgements.
I think the circuits sounds "rounder", if you can imagine such a thing. I can't discount the manner in which I breadboarded the thing - it all matters, I suspect. The tube seems to run perceptibly hotter; that is, the actual tube seems hotter to the touch that the Valvecaster. Is that "good"? I have no idea. I prefer what the Gain pot does sitting between the tube segments.
I've lucked out into a wall wart that's providing a solid 12VDC/1A and it's actually quiet. Very curious to see what stacking a couple of ValveMasters together might sounds like (TwinMaster?), and my reading suggests that 1A might be enough to power it, but again, I'm obviously not an engineer and cannot empirically say.
I want about 50% more crunch than I have, without it getting all crazy. Read some of the notes suggesting messing around with R2 & R3 and I may do that, but I need to understand more about the implications of this before doing so.
It sounds good to me.
Quote from: frequencycentral on January 04, 2012, 07:09:04 PM
Quote from: Yeahno on January 04, 2012, 04:04:55 PM
Heh. The Valvecaster on the breadboard has just become a Valvemaster. The sound is growing on me.
I'd be interested in your opinion re any differences/advantages of either varient.
Rick I have been playing with the valvemaster, but at 46v (I only had 50v caps..)
so far I can get good tone from this but the 10uf on the cathodes allows too much bass, only one tube I have does not "Fart" out once the gain is raised.
I will go to a 1uf and then play from there. will let you know
I also changed the plate resistors to 68K and I have no tone stack but I am thinking of using the Garnet stack
(http://amps.zugster.net/images/articles/tonestacks/garnet-schem.gif)
136 pages and memory starts to fall...don't remember if that was argumented enough, but hey sometimes it's good to go back to basics, it can be helpful for new guys and for veterans as well...
Trying to help out my country mate Teo, I remembered/realized that small difference between original Dano schem (http://www.beavisaudio.com/projects/ValveCaster/MatsuminValveCaster.gif) and original Dano wiring example (http://www.beavisaudio.com/projects/ValveCaster/MatsuminValveCasterWiring.gif).
As you can see, there's a small difference in the way the tone parts (pot and c4 cap) are arranged.
In the schem, after c3 (1µ polar. or NP) there is one leg of c4 with the other leg to the tone pot (pin 1) and then to ground (pin 3 and 2). also after c3 there's tied the volume pot.
in Dano's wiring the the tone pot is just after c3, at pin 3 (and it works the opposite that way, fulyy CCW you have no attenuation of the highs) and the signal to the volume at the same outer pin of that tone pot. c4 comes from the wiper of tone pot and then to ground. I don't know if that makes that HUGE difference (I believe not) but maybe it's something to point out. My very first vero layout (http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=39952&g2_serialNumber=2) was made using the wiring diagram as its starting point.
Quote from: iccaros on January 04, 2012, 08:04:10 PM
Quote from: frequencycentral on January 04, 2012, 07:09:04 PM
Quote from: Yeahno on January 04, 2012, 04:04:55 PM
Heh. The Valvecaster on the breadboard has just become a Valvemaster. The sound is growing on me.
I'd be interested in your opinion re any differences/advantages of either varient.
Rick I have been playing with the valvemaster, but at 46v (I only had 50v caps..)
so far I can get good tone from this but the 10uf on the cathodes allows too much bass, only one tube I have does not "Fart" out once the gain is raised.
I will go to a 1uf and then play from there. will let you know
I also changed the plate resistors to 68K
try a 12at7, I found that in the same CKT as a 12au7, low voltage, it give more crunch.. I picked 5 up on ebay for $20..
Also I'd like to give a little suggestion at the new guys, like Yeahno and Rick899...
There are two paths for you, based on your needs or will to experiment...
- path a - K.I.S.S.
Valvecaster is such an easy ckt to build, it give a nice and warm booster/overdrive when used at 12V with the right tube.
Get rid of the useless tone pot as I did shortly after my first one like 3 years ago!
- path b - more complete builds
A valvy is not that much different from the first two tube stages of your ordinary tube amp - studying tube preamps may lead you to my same conclusion. Some already went further, like the great ROG renditions of tube preams/amps with FETs, or cloning a preamp, like the jcm800 preamp you can find on the net. it is the whole preamp part, 4 gain stages (using 2 tubes) with regular TMB tone stack.
As long you got your feet wet with tubes, you cannot go back...just choose your path!
Adrain,
Thanks for the link with the tube buffer!!
Interesting... Did anyone try this with low voltage (12-50V)?
I still have no tryed with a 9V battery... i fixed some GND to the circuit but it does the same error...
I took again values on PIN1/2/6/7 and i got the same values...
But... i set scale on 200mv and i took signal directly from 6.3jack from the guitar (a stratocaster 70 with vintage custom shop PU ).
I had signals around 0-30mv maximum...
I tryed to pick up signal from PIN2 with a compressor before the valvecaster and i have only 20mv while i read arount that it should be at least 200mv...
Should i try to change R1 1Mohm with a one with less resistance?
R1 is a grid leak resistor and should not be in path of signal. Reducing that would not help.
this may help
http://www.diystompboxes.com/pedals/debug.html (http://www.diystompboxes.com/pedals/debug.html)
fixed it...
I found a 24V 1Ampere power supply stabilized at home... it runs very very very well!!!
Thanks a lot guys!!!!
PS: fixed work tension to 12V (12.4 from the tester)
It runs very fine!
I also added a little red led that were alone in one of my work boxes under the socket!
This is the result!
(http://img835.imageshack.us/img835/3585/lucer.jpg)
(http://img845.imageshack.us/img845/4950/buio.jpg)
nice job, so it was just the power supply?
thanks!
yep, it was just the power supply!
i supposed it would had more gain.. i play classic blues like clapton/dire straits wiyh my group.. i usually play rithm OD with the crunch canal of my peavey classic 50 end i boost signal with the pedal OD (in this case the new one).
So, is there a way to gain a little more overdrive changing some components?
Quote from: Yeahno on January 04, 2012, 07:54:10 PM
QuoteI'd be interested in your opinion re any differences/advantages of either varient.
I'm afraid I can only speak to the perceived differences. I'm going to leave the engineering aspects of it to the people here who are qualified to make such judgements.
I think the circuits sounds "rounder", if you can imagine such a thing. I can't discount the manner in which I breadboarded the thing - it all matters, I suspect. The tube seems to run perceptibly hotter; that is, the actual tube seems hotter to the touch that the Valvecaster. Is that "good"? I have no idea. I prefer what the Gain pot does sitting between the tube segments.
I've lucked out into a wall wart that's providing a solid 12VDC/1A and it's actually quiet. Very curious to see what stacking a couple of ValveMasters together might sounds like (TwinMaster?), and my reading suggests that 1A might be enough to power it, but again, I'm obviously not an engineer and cannot empirically say.
I want about 50% more crunch than I have, without it getting all crazy. Read some of the notes suggesting messing around with R2 & R3 and I may do that, but I need to understand more about the implications of this before doing so.
It sounds good to me.
There's no recorded example of the differences? That would be great as all you can hear on you tube is valvecasters both on 9V and 12V. They're OK but if the valvemaster is even better that's the circuit I should go for.
Quote
There's no recorded example of the differences? That would be great as all you can hear on you tube is valvecasters both on 9V and 12V. They're OK but if the valvemaster is even better that's the circuit I should go for.
I'm an even worse guitar player than I am a circuit bender. Otherwise, I'd oblige.
I didn't say it was better. I said I liked the way it sounded. I prefer it.
That said, converting from the Caster to the Master took me all of about 15 minutes, once I'd soldered up a different pot, so build both. It's good fun!
Quote from: Teo87 on January 05, 2012, 01:02:23 PM
thanks!
yep, it was just the power supply!
i supposed it would had more gain.. i play classic blues like clapton/dire straits wiyh my group.. i usually play rithm OD with the crunch canal of my peavey classic 50 end i boost signal with the pedal OD (in this case the new one).
So, is there a way to gain a little more overdrive changing some components?
try a different 12au7 or in my case the 12at7 gave more gain.
Quote from: Yeahno on January 05, 2012, 07:01:00 PM
Quote
There's no recorded example of the differences? That would be great as all you can hear on you tube is valvecasters both on 9V and 12V. They're OK but if the valvemaster is even better that's the circuit I should go for.
I'm an even worse guitar player than I am a circuit bender. Otherwise, I'd oblige.
I didn't say it was better. I said I liked the way it sounded. I prefer it.
That said, converting from the Caster to the Master took me all of about 15 minutes, once I'd soldered up a different pot, so build both. It's good fun!
I might do it! But first I have to finish my vintage multi-fx. I have it halted for over one month and I realy want to finish it first before I jump into another project. But I'm pretty shure that the spare old Philips tube will end up on one of this babies.
I've read the article about triodes operating at low voltages and it's very interesting and easy to understand even for a non-electronic engineer like myself (although it requires that you know some basics).
the Valvemaster:
(http://dl.dropbox.com/u/967492/Valve%20Master.JPG)
- interstage gain pot - no more crackle - like a 'real' tube circuit. ;)
- proper cathode biasing of both triodes - like a 'real' tube circuit
Here's my freshly made Vero layout may you ever need...
(http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=46809&g2_serialNumber=2)
Is this applicable with 12AX7?
thanks
No doubt ,yes . They are the same except you get MOAR gain with 12AX7 .
PS : Your tube's base are belong to me :icon_mrgreen:
Quote from: fretzburner on January 05, 2012, 08:19:18 PM
Is this applicable with 12AX7?
thanks
While a 12ax7 has more gain, I have not found it to be so in this low voltage design. I get almost unity gain at 12volts and at 45v it works much better but the 12at7 and 12au7 give me much more gain, and more grit.
Quote- interstage gain pot - no more crackle - like a 'real' tube circuit. Wink
- proper cathode biasing of both triodes - like a 'real' tube circuit
Adrian,
Can I presume that this is "better"? That is, does this explain why the tube runs hotter: because it is properly biased? And by running closer to optimum due to biasing, does this explain why I prefer this circuit?
Attached is a DIYLC PNG file pic of a layout of the DualCaster. I know it is rather small but can anyone tell from it if I got all the connections right. Or: Will this work if I build it the way shown in the layout? Thanks.
(http://i1126.photobucket.com/albums/l603/henry7895/DualcasterPNG.png)
Quote from: Yeahno on January 05, 2012, 10:31:51 PM
Quote- interstage gain pot - no more crackle - like a 'real' tube circuit. Wink
- proper cathode biasing of both triodes - like a 'real' tube circuit
Adrian,
Can I presume that this is "better"? That is, does this explain why the tube runs hotter: because it is properly biased? And by running closer to optimum due to biasing, does this explain why I prefer this circuit?
The above quote was written by Rick introducing his variation.
I don't know if cathode biasing can introduce the difference you say, maybe yes, but it's not only that I guess...
I'd say we should all go thru some already tested paths, as a lot has been done and can be used/copied successfully, just take (insert your favourite amp brand) preamp and play with its schem!
Now I don't want to talk tech more than I can do, but basicly you have hot tubes from the heathers (as their name implies I guess!!! XD), still I can see in Rick's variation an unusual 47k at the plates, while the common res. is a 100k. Can't tell you without experimenting what's the result in halving those plate resistors or if that gets you more heat.
just one of the tube preamps I've found - SCHEM (http://tremolo.elektroda.net/Przedwzmacniacze/A%20la%20Fender.gif)
In those ckts as the Valvy itself, I'd get rid of the input cap, and have a 1M to ground at first and then a resistor to grid, usually you see a 68k, but I had some success going as low as 10k, a 22k or 33k is quite good!
I have been experimenting lately with Fenderish ckts at medium voltage, that makes me say a lot more can be done just starting from the basics!
Renegadrian:
In regard to the freshly made vero layout of the Valvemster: Are the green circles numbered "2", "5", and "6" mislabeled?
BTW: Do they still have those Bibiti trucks all over Rome selling frozen bottles of water? In Rome in July those frozen bottles of water really come in handy!
Quote from: Yeahno on January 05, 2012, 10:31:51 PM
Quote- interstage gain pot - no more crackle - like a 'real' tube circuit. Wink
- proper cathode biasing of both triodes - like a 'real' tube circuit
Adrian,
Can I presume that this is "better"? That is, does this explain why the tube runs hotter: because it is properly biased? And by running closer to optimum due to biasing, does this explain why I prefer this circuit?
Just to help, I hope
as Renegadrian stated, you have heaters in the tube that do just that, they heat the cathode causing electrons (electron cloud) to boil off the metal, these electrons are then free floating in the vacuum until you have a positive charge that can attract them. The Plate is too far away for them to all go there so most fall back to the cathode. The screen or grid (pin 2 and pin 7) look like the screen on a window or door in concept. As you send signal to the screen, it is placed between the cathode and plate, and attracts electrons as it goes positive in comparison to the cathode. Since it has holes most of the electron cloud passes through and since its now accelerated it can reach the plate (anode).
as the tube conducts it draws current. this current draw over the plate resistor causes a swing in voltage which in proportion to the input signal based on how linear the the tube is operating.
Since the tube conducts based on how positive the grid is to the cathode, when we elevate the cathode with a resistor we make grid look more negative, so it takes a larger signal to cause it to conduct, and in our case a larger signal to make it overdrive.
All of that to say two things.. sorry
The heaters provide heat, the plate current can add heat, but at these low voltages they do not compared to the heater. The reason your tube may be hotter, could be many, different tubes even in the same brand draw slightly more heater current making them run hotter . or two when you changed the design you moved a heater wire which gave it better connection and not its allowing more current to flow over the heater.
bias correctly was not the issue with the Valvecaster, and I think 1K is too much for this low voltage design, I am looking at ~500R. this is a better design because it removed the noise when changing gain, as no DC is on the pot. There are many ways to change gain, in the valvemaster you change the limits in how much signal passes between stages, in the original you change when and how much signal the grid needs to conduct .
AS for 47K, this is a low voltage design, I like 68K for this, but I feel that 100K is too large, but its almost like a 220K on a normal design. As you lower resistance you lower gain, as you need the current passing through the resistor which causes the voltage swing, the more voltage the resistor drop the more the swing difference.. hope that makes sense.
Steve,
QuoteJust to help, I hope
Enormously.
Quote
All of that to say two things.. sorry
Not at all!
Quote
The heaters provide heat, the plate current can add heat, but at these low voltages they do not compared to the heater. The reason your tube may be hotter, could be many, different tubes even in the same brand draw slightly more heater current making them run hotter . or two when you changed the design you moved a heater wire which gave it better connection and not its allowing more current to flow over the heater.
Got it.
Quotebias correctly was not the issue with the Valvecaster, and I think 1K is too much for this low voltage design, I am looking at ~500R. this is a better design because it removed the noise when changing gain, as no DC is on the pot. There are many ways to change gain, in the valvemaster you change the limits in how much signal passes between stages, in the original you change when and how much signal the grid needs to conduct .
Sorry, I'm not sure which you're referring to. You mean that you'd recommend exploring 500R instead of the 1K on the Valvemaster? And do you mean that the Valvemaster is a better design?
QuoteAS for 47K, this is a low voltage design, I like 68K for this, but I feel that 100K is too large, but its almost like a 220K on a normal design. As you lower resistance you lower gain, as you need the current passing through the resistor which causes the voltage swing, the more voltage the resistor drop the more the swing difference.. hope that makes sense.
This sounds like mucking around with the 47K on the Valvemaster would be a good idea!
QuoteSorry, I'm not sure which you're referring to. You mean that you'd recommend exploring 500R instead of the 1K on the Valvemaster? And do you mean that the Valvemaster is a better design?[\quote]
you asked if the valvemaster was a better design because its biased correctly before. I was saying that the bias adjustable is right to the valvecaster and its intended goal, so its not about right, just opinion, and I like a traditional cathode bias.
I am recommending between 400R and 500R for the first stage, I think the guitar signal is too low to get any overdrive @ 1K, I find that the first stage stays really clean, and I do not want that, I want a little overdrive (clipping) when I really hit the strings on the guitar, this makes it more "touch" sensitive in my opinion.
I like the Valvemaster design better, but that is my opinion
QuoteThis sounds like mucking around with the 47K on the Valvemaster would be a good idea![\quote]
I would try between 47K and 86K.. There are many ideals, and it changes based on the tube you use, a 12au7 responds differently than a 12ax7 or even than a 12at7, so you may want to try on a bread board first.
QuoteSorry, I'm not sure which you're referring to. You mean that you'd recommend exploring 500R instead of the 1K on the Valvemaster? And do you mean that the Valvemaster is a better design?[\quote]Quote
you asked if the valvemaster was a better design because its biased correctly before. I was saying that the bias adjustable is right to the valvecaster and its intended goal, so its not about right, just opinion, and I like a traditional cathode bias.
Got it.
Quote
I am recommending between 400R and 500R for the first stage, I think the guitar signal is too low to get any overdrive @ 1K, I find that the first stage stays really clean, and I do not want that, I want a little overdrive (clipping) when I really hit the strings on the guitar, this makes it more "touch" sensitive in my opinion.
I just swapped in a pair of Vishay 499R (yes, 499...), left the 10uF caps in place and I'd say it sounds better. More breakup, and as you said, more sensitivity to touch. With the volume knob on the Tele rolled back, it's clean. Crank it and it starts to growl very nicely.
I can't tell you how much fun this is.
Quote
I like the Valvemaster design better, but that is my opinion
As do I.
Quote
This sounds like mucking around with the 47K on the Valvemaster would be a good idea![\quote]Quote
I would try between 47K and 86K.. There are many ideals, and it changes based on the tube you use, a 12au7 responds differently than a 12ax7 or even than a 12at7, so you may want to try on a bread board first.
It's all staying on breadboard until I've got something I like a lot.
Many thanks for the help and suggestions.
Quote from: Rick899 on January 06, 2012, 11:13:16 AM
Renegadrian:
In regard to the freshly made vero layout of the Valvemster: Are the green circles numbered "2", "5", and "6" mislabeled?
BTW: Do they still have those Bibiti trucks all over Rome selling frozen bottles of water? In Rome in July those frozen bottles of water really come in handy!
layout corrected, thx for spotting!
yeah you can see those lil trucks all over the place! Damn!!! XD
Quote from: Yeahno on January 06, 2012, 06:41:49 PM
I can't tell you how much fun this is.
Now that's the best part of it!!! ;-)
Hmm. Should I be able to swap in a 12AT7 tube for the 12AU7 tube in this Valvemaster circuit without making any changes?
Quote from: Yeahno on January 07, 2012, 11:46:23 AM
Hmm. Should I be able to swap in a 12AT7 tube for the 12AU7 tube in this Valvemaster circuit without making any changes?
no harm will come if you do, and you may like it.. Tube rolling can be fun..
to answer more clearly, you can swap a 12au7, 12at7, 5751 and some 12ax7, with no changes.
So if I swap it into a working circuit and get no sound, suspect the tube?
yes
Got a bad tube. The dealer swapped it for a good one.
But now, whereas the 12au7 is nicely audible & crunchy, if I simply power off the circuit and roll the tubes, the 12at7's output is very low. It's definitely working, but I have to turn the volume way up on the amp in order to hear it. I'm thinking this has something to do with the performance characteristics of the tube and the impedance I'm presenting to it.
Must do some digging.
These are low voltage design, or better termed as running the tube out of Specification. I rolled through (4) 12au7 and (3) 12AT7 before I found the one that liked the low voltage. But I have other amps I can use these tubes in..
This is why professional designs either have a voltage multiplier or a buffer before and after. So that no matter what tube is put in, it will perform.
Quote from: fretzburner on January 05, 2012, 08:19:18 PM
Is this applicable with 12AX7?
thanks
In the article about driving triodes at low power that therminator posted, 12AU7 was considered to be the best one to play with because of it has a lower grid current and it's easier to bias (less sensitive).
An interesting statement on the article is the one on page 4 regarding Figure 7 and pull-up grid-leak biasing: it's the biasing method of Butler's Tube Driver.
I'm gonna try changing some values to lower the mid/low ends!
QuoteIn the article about driving triodes at low power that therminator posted
Link?
its in my first post
http://www.diystompboxes.com/smfforum/index.php?topic=91745.0
This is my first post here, but I have been lurking for a while. There is definitely some good info here!
I just finished building a dual valve caster. I built it per the schematic, and once I got it to stop picking up AM radio, it sounds real nice.
I have noticed that when I have both gains all the way up, there is a TON of sag. So much so that it cuts out sometimes. Its a smooth in and out, and ALMOST sounds like a noise gate. What could be causing this?
I am using a 12v 1250ma wall wart, and vintage Raytheon tubes.
Here is a pic:
(http://i268.photobucket.com/albums/jj26/thebattens/photo-1.jpg)
The extra hole is from a previous build and the extra switch does nothing yet.
it could be a few things
1) your power supply is not really able to handle 1.2 amps as it says
2) you are not hearing sag but cut off
3) something is wired wrong
4) your vintage tubes are dead and need replaced
Quote from: blown240 on January 17, 2012, 09:29:53 PM
(http://i268.photobucket.com/albums/jj26/thebattens/photo-1.jpg)
Where did you find those RED anodized aluminum knobs??
Me likey ;D
Quote from: iccaros on January 18, 2012, 01:32:15 AM
it could be a few things
1) your power supply is not really able to handle 1.2 amps as it says
2) you are not hearing sag but cut off
3) something is wired wrong
4) your vintage tubes are dead and need replaced
1. Thats entirely possible. Whats the minimum that a dual valve caster needs?
2. Thats probably true too, what causes cutoff?
3. I double checked it all, and i am pretty sure its all correct.
4. I ran them thru a tube tester and they are good, old but good. They are well above minimum spec.
I got the red knobs from a dead Carvin bass amp. They may sell the seperatly.
Quote from: blown240 on January 18, 2012, 10:19:57 AM
Quote from: iccaros on January 18, 2012, 01:32:15 AM
it could be a few things
1) your power supply is not really able to handle 1.2 amps as it says
2) you are not hearing sag but cut off
3) something is wired wrong
4) your vintage tubes are dead and need replaced
1. Thats entirely possible. Whats the minimum that a dual valve caster needs?
2. Thats probably true too, what causes cutoff?
3. I double checked it all, and i am pretty sure its all correct.
4. I ran them thru a tube tester and they are good, old but good. They are well above minimum spec.
I got the red knobs from a dead Carvin bass amp. They may sell the seperatly.
1)you should need about 312 ma (heaters are 150 each tube , and about 3 ma per triode max which there are 4 triodes in this design)
2) cut off happens when you exceed the inputs ability to conduct anymore, this leads to distortion at one level, and to complete cutoff at another. Since a guitar puts out more than one frequency at a time, you could cut off a single band of audio while another is not, so you may loose some treble or bass, while the other frequencies are not in cut off. You may have to loose some gain between stages, adding a bigger resistor, or change capacitor values to filter out frequencies that cause issues.
3)cool, post voltages around the tube please...
4) I am not touching that :icon_biggrin:
Quick question- I am having a hum issue on my Valvy. When people say to wire your heater grounds separate from your signal ground, where am I supposed to ground the heaters? To the DC jack itself? I ground my signal and heaters on the vero, on the same strip. I'm having some hum issues.
its very unlikely that you will get noise off DC heaters, that is a problem with AC heaters, but everything is possible.
But to your question, I have a capacitor to ground from the input of the power supply and that ground lead I connect to all signal grounds and I connect all power grounds to the jack. I believe that makes zero difference on this design as there is little room from a loop. In any case its a star like network and not everything connecting to the closest part this is also connected to ground.
For versions with a Voltage multiplier, signal ground comes from the last capacitor of the multiplier, while power ground (heaters, voltage multiplier, LED) come from the power jack.
Tubes can be noisy, but also things like voltage regulators can create noise, or in my first pedal a bridge rectifier I put in place to correct polarity before the pedal CKT.
Bad solder joint, signal wires running parallel in close proximity, noisy power supply
Quote from: iccaros on January 18, 2012, 08:00:50 PM
3)cool, post voltages around the tube please...
Here are my voltages:
Tube 1
1=.61
2=.53
3=0
4=12
5=.63
6=.62
7=.36
8=0
9=not used
Tube 2
1=.59
2=.41
3=0
4=12
5=.62
6=.6
7=.35
8=0
9=not used
Quote from: blown240 on January 19, 2012, 01:32:34 PM
Here are my voltages:
Tube 1
1=.61
2=.53
3=0
4=12
5=.63
6=.62
7=.36
8=0
9=not used
Tube 2
1=.59
2=.41
3=0
4=12
5=.62
6=.6
7=.35
8=0
9=not used
Those are not right in any way.. pin one a plate at 12v should show 7v about and 6 should be close to the same. The others are ok, can you send a picture? but it looks like plates are not connected through a resistor to V+, if you pull the tubes you should read 12v on pin 6 and 1 to ground.
Reading pin 4 and 5 should be between them, but to ground is ok for this. I see a .62 rise in your ground to ... ground. In this design that will change how the tubes are biased, as the first stage will not boost much.
pin 2 and 7 should be a DC 0 volts, to ground and a negative voltage to pin 3 and 8 respectively.
This could be a ground issue
The only thing I can see that may be wrong is that I have the 470k resistor from pin 7 going to pin 8 and then to ground. Basically I am using the pin 8 ground to ground pin 7. could this be messing me up? also the meter is set to 20v...
in order to have dc voltage on pin 2 and 7, you have to have DC leaking from the Grid or from the coupling capacitor. But that is not bothering me, its the .6 volts on the plates.. The tube can not work with that low a voltage. if you draw 1mA across a 47K resistor you would drop about 4.5 volts so you should see about 7 volts on the plates Pin 1 and pin 6.
can you take a picture and post it?
Here are some pics. I know its ugly, but I am new at this. (you should have seen the first amp I built :icon_redface:)
Its odd that it sounds so good for the voltages being so far off. Even my amp snob brother in law thinks it sounds great. He wants me to build him one.
(http://i268.photobucket.com/albums/jj26/thebattens/Pedals/photo1.jpg)
(http://i268.photobucket.com/albums/jj26/thebattens/Pedals/photo2.jpg)
(http://i268.photobucket.com/albums/jj26/thebattens/Pedals/photo3.jpg)
(http://i268.photobucket.com/albums/jj26/thebattens/Pedals/photo4.jpg)
hmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmm
Why does it sound so good, I have no ideal, unless you are not making a good ground connection when reading voltages, but consistent on pin 4... :icon_exclaim:
With so much solder there could be a lot of flux messing up the readings. if you pull the tube and read voltages from the tube side what do you get?
Quote from: iccaros on January 19, 2012, 12:40:22 PM
its very unlikely that you will get noise off DC heaters, that is a problem with AC heaters, but everything is possible.
But to your question, I have a capacitor to ground from the input of the power supply and that ground lead I connect to all signal grounds and I connect all power grounds to the jack. I believe that makes zero difference on this design as there is little room from a loop. In any case its a star like network and not everything connecting to the closest part this is also connected to ground.
For versions with a Voltage multiplier, signal ground comes from the last capacitor of the multiplier, while power ground (heaters, voltage multiplier, LED) come from the power jack.
Tubes can be noisy, but also things like voltage regulators can create noise, or in my first pedal a bridge rectifier I put in place to correct polarity before the pedal CKT.
Bad solder joint, signal wires running parallel in close proximity, noisy power supply
Cool, thanks man, I will try another PS and see what happens. I already have a 1000uF cap on the power terminals.
Quote from: runmikeyrun on January 20, 2012, 03:44:57 PM
Quote from: iccaros on January 19, 2012, 12:40:22 PM
its very unlikely that you will get noise off DC heaters, that is a problem with AC heaters, but everything is possible.
But to your question, I have a capacitor to ground from the input of the power supply and that ground lead I connect to all signal grounds and I connect all power grounds to the jack. I believe that makes zero difference on this design as there is little room from a loop. In any case its a star like network and not everything connecting to the closest part this is also connected to ground.
For versions with a Voltage multiplier, signal ground comes from the last capacitor of the multiplier, while power ground (heaters, voltage multiplier, LED) come from the power jack.
Tubes can be noisy, but also things like voltage regulators can create noise, or in my first pedal a bridge rectifier I put in place to correct polarity before the pedal CKT.
Bad solder joint, signal wires running parallel in close proximity, noisy power supply
Cool, thanks man, I will try another PS and see what happens. I already have a 1000uF cap on the power terminals.
Do you have regulation?
Quote from: dano12 on December 13, 2007, 09:31:09 AM
Regarding the 386 amp, that's the route I'm taking with my wired tube socket thing. Trying to fit it in a small plastic case.
For the questions about using a tube other than the 12AU7, as said earlier, they are higher gain and won't work nicely unless you modify the circuit, I don't know how to do that part.
tubesandmore.com has the tube and sockets, it is the standard 9-pin tube socket you would use for guitar amp preamp sections.
Here is a rough *unverified* wiring diagram for anyone who wants to try it.
(http://www.beavisaudio.com/Projects/ValveCaster/MatsuminValveCasterWiring.gif)
Wow very cool. I will build this and post back. I have most if not all parts on hand.
Hi guys, I've just discover another starved plate tube driver circuit that realy sounds well.
The main differences are: They have an opamp before the valve to raise the signal level and drive the valve into distortion easier (my guess, waiting for the designer to confirm) and they run the heaters out of an AC 16V tap. Running the heaters with AC prevents hum and could be a nice solution to add to the Valvemaster.
I'd rather build the Valvemaster as it would fit better in my rig: I could run the Laney Cub 12 preamp at low gain for a total clean/big headroom sound and add the Valvemaster as an additional gain stage either before the amp input or in the effect loop (in this case the additional stage it will be placed after the 4 inicial stages, gain and EQ controls and before the last 2 pre-amp stages, tone control and power stage).
JRM
to fix your statements, a Buffer before the tube has been done,as you know, but some people want an all tube solution. The Dual Caster does this in effect, if you take the first tube and make it a cathode follower, you may see better drive of the second, at least more consistence between tubes.
as for using AC. I would doubt they would run the heaters using 16v ac, as that will kill the tube quickly, they are rated at 6.3 parallel or 12.6 series.
as for "with AC prevents hum and could be a nice solution to add to the Valvemaster"
This is not true, you can not get HUMM from DC as you can not hear DC. It would be common to run heaters in a tube amp with DC, but there is a lot of expense in rectification, and dealing with ripple, its just easier to use 6.3 ac. In a dual triode it is common to use the second half as the first gain stage as its less likely to carry over noise generated from AC heaters.
Sorry iccaros, I might haven't explained myself well enough. They run the heaters in series from an 16V AC supply but they have a resistance to decrease the voltage. The claim that it solves hum problems isn't mine but the builder's as I don't even have the knowledge about valves to know it (although I've understood your explanation about the impossibility of DC being the culprit of hum!).
On the other hand, many thanks for your answer as it helped me to decide that I'll build a Valvemaster as soon as I finish my other projects: it's simpler and will work better in my effects chain as I can use it alone or to boost my Big Muff or Fuzz Face. Another thing that I'll try is to use the Valvemaster after my powerboost (in a clean boost setting) as I think it will raise the signal level enough to overdrive the Valvemaster.
JRM
Do you have a link to that build
Thanks
I have the schematics here: http://img341.imageshack.us/img341/3121/bajarealtubeoverdrivesc.png
@JRM = I've built the baja tube pedal and its got some hum to it. Its not a bad pedal but I need a noise gate or suppressor to keep it quiet. If you run it thru a clean channel. Its not bad but when you use it to drive distortion, it hums like crazy. My dual valvcaster runs quiet compared to the baja pedal.
Thanks Paulyy! I've already decided to go for the valvemaster anyway.
Quote from: buildafriend on January 22, 2012, 05:36:32 PM
Quote from: dano12 on December 13, 2007, 09:31:09 AM
Regarding the 386 amp, that's the route I'm taking with my wired tube socket thing. Trying to fit it in a small plastic case.
For the questions about using a tube other than the 12AU7, as said earlier, they are higher gain and won't work nicely unless you modify the circuit, I don't know how to do that part.
tubesandmore.com has the tube and sockets, it is the standard 9-pin tube socket you would use for guitar amp preamp sections.
Here is a rough *unverified* wiring diagram for anyone who wants to try it.
(http://www.beavisaudio.com/Projects/ValveCaster/MatsuminValveCasterWiring.gif)
Wow very cool. I will build this and post back. I have most if not all parts on hand.
Can you please help me with the value of the capacitors, resistors etc. (I only see potentiometer values on the picture...)
It's all here
http://www.beavisaudio.com/projects/ValveCaster/ (http://www.beavisaudio.com/projects/ValveCaster/)
Thx
Hi guys! I want to build this circuit as a part of a preamp for recording. Most likely I'll use two ECC 82's (Twincaster). What's confusing me is this; I'd like to use higher voltage supply, minimum 18V, but for the heaters I have to use 12.6V, right? So, I have this 18V transformer. What kind of IC should I use to get 18V regulated for the valves. Also, can I use another IC (or Zenner) in series after that point to get the 12V for the heaters, and which IC would that be?
Thanks!
you have several options
A resistor to lower voltage, gets hot is good for limited voltage ranges once calculated (voltage-drop/current) and wattage, voltage * current
you could use a Zener diode with the right dropping voltage and calculated wattage.
a Voltage regulator like a LM317 works well, needs heat sink, works with a wide range of voltage inputs
Merlin has good write up on tube heater supplies http://www.freewebs.com/valvewizard/heater.html (http://www.freewebs.com/valvewizard/heater.html)
at the Bottom is well regulated 6.3 supply, and a good rolling supply if you want more flexibility in tubes used. NOTE: 12a*7 type tubes run off 12.6 or 6.3 depending on how they are wired
Or you could use this power supply...
http://www.generalguitargadgets.com/pdf/ggg_bipolar_ps.pdf (http://www.generalguitargadgets.com/pdf/ggg_bipolar_ps.pdf)
Omit the negative supply output and you are ready....(omit d2,c2,c4,rg2,c6)
For 18volt output the chart says 24-30volt transformer,however i got it working using a 18volt transformer once...
I guess you will have to try yourself ;)
would it be a good idea to replace the tone part of the circuit by a Baxandall tube circuit?
like this one:
(http://farm8.staticflickr.com/7059/6911102673_c52e4d6f3d_z.jpg)
i believe this kind of circuit has to be buffered but i'm not sure.
i have the full paper that i can upload somewhere for anyone to download it if interested!
I have a question regarding using the 7812 voltage regulator to eliminate the hum when using a 12V PS. I recently built the original VC using this schematic, (http://i622.photobucket.com/albums/tt308/reaperQ45/Valvecaster/Scan_Pic0001.jpg)
I have noted my resistor and capacitor values based on others trial and errors. I have tested a variety of tubes 12ua7 and the 12ax7. Using these R/C values, the 12ax7 sound not bad at all. For testing purposes I am using a Fender Stratocaster with Klein pickups and a Fender 15G amp.
For PS I am using a BOSS red label 9.6VDC 200mA and a Insignia (generic) 12VDC 700mA. Dependent upon which tube I am testing, I will get very little to no hum using the BOSS PS. The Insignia will give me varying levels of hum dependent on the tube being tested.
The 12VDC clearly is the better choice for more headroom, but the 9VDC sounds good as well. I did not change anything on the circuit to switch between 9 and 12VDC, just plug them in.
So, to get to my point. I used Renegadrian's layout, http://www.aronnelson.com/gallery/main.php/v/Renegadrian/regulator.gif.html, to integrate the voltage regulator into my circuit, shown on the above diagram. When I engage the effect, I get nothing but hum, no sound what so ever. I took it out and everything works. So not being the brightest with circuits, what did I do wrong?
Can someone explain to me what the difference is between the above schematic and this one that Beavis put out, http://www.diystompboxes.com/smfforum/index.php?topic=63479.2500, look at post #2509. The main difference is the way the Volume, Tone and Gain are connected in the circuit. It was noted that someone said the schematic I used would not work, but all three potentiometers function as they should.
Thanks,
Patrick
Is the ''head'' of the regulator touching the chasis?
IT SHOULDN'T!
Also is your dc jack plastic or metal?
Hey here is an idea!
Post some pictures! ;)
Quote from: Frances Rhodes on February 20, 2012, 01:56:24 PM
would it be a good idea to replace the tone part of the circuit by a Baxandall tube circuit?
like this one:
(http://farm8.staticflickr.com/7059/6911102673_c52e4d6f3d_z.jpg)
i believe this kind of circuit has to be buffered but i'm not sure.
i have the full paper that i can upload somewhere for anyone to download it if interested!
I would place it between the stages and up your voltage, or better, use a dualcaster, this way you will have a recovery stage
Right now the circuit is not in an enclosure. I have a heatsink on the regulator. Here are some pictures.
(http://i622.photobucket.com/albums/tt308/reaperQ45/Valvecaster/DSC07798.jpg)
(http://i622.photobucket.com/albums/tt308/reaperQ45/Valvecaster/DSC07797.jpg)
(http://i622.photobucket.com/albums/tt308/reaperQ45/Valvecaster/DSC07799.jpg)
So I have the ground leg of the 7812 to ground on the DC jack, in leg to positive on DC and out leg of the 7812 going to lug 4 on my foot switch which is tied to C1 and pin 2. The 100uf is soldered to the ground and in legs of the 7812. Is the out leg for the 7812 good at lug 4, or does it need to be tied in elsewhere?
Quote from: iccaros on February 20, 2012, 04:45:12 PM
Quote from: Frances Rhodes on February 20, 2012, 01:56:24 PM
would it be a good idea to replace the tone part of the circuit by a Baxandall tube circuit?
like this one:
(http://farm8.staticflickr.com/7059/6911102673_c52e4d6f3d_z.jpg)
i believe this kind of circuit has to be buffered but i'm not sure.
i have the full paper that i can upload somewhere for anyone to download it if interested!
I would place it between the stages and up your voltage, or better, use a dualcaster, this way you will have a recovery stage
i would try to draw it with eagle cadsoft but i looked for tubes and never found how to add tubes to schematics... :icon_redface:
and also i would replace the penthode by a triode to have a 12AU7 and a 12AX7
Quote from: Dongle on January 04, 2012, 06:26:03 AM
Well, my thought on this issue is that I dont care about the design of anything - as long as it sound sgreat.
And if you like the sound of an IC before the pedal, why dont you go for it? An all-tube-approach does not help you, if you dont play it because it does not sound as good.
In addition: I think even the hardcore tubers agree, that a buffer behind the tube is needed. The buffer also has an IC... So why not put anotherone in front of the pedal to boost?
And by the way: ICs are still analogue.... so you still would have an "analogue, hand wired tube pedal"...
Dongle: I'm about to start putting a twin Valvecaster together. I was wondering if you are still using your Valvemaster configuration and if you still like it. Does the gain behave any differently after you moved it between the 1st and 2nd stages?
Any ideas about where Vout from the regulator is supposed to be wired with the Valvecaster?
A regulator by itself won't give perfectly clean DC, especially if your wall-wart is being "pulled-down" below 12.6 volts (remember, the 7812 will eat up about 0.6 volts). Try adding a filter cap or two - one before and one after. Try maybe 10uF and see if that helps. If so, you can start playing around with values to get the hum to an acceptable level, or eliminated. It's been a while, but I recall having to add filter caps on mine to help clean things up...even 10mV of fluctuation can cause pretty bad hum. I think I eventually got mine down to about 2mV ripple before I was satisfied.
Zipslack my WW pulls 18.15V at the wall so it is sufficient to use with the 7812. What I am trying to do is get it wired properly to my circuit. Ground on the reg goes to ground on the jack, in on the reg goes to positive on the jack, my question is, "Where does the out on the reg tie into the circuit?" I have not had to use a regulator on any other pedal builds so I am a little unsure where to tie in.
IF you are using a regulator, it becomes your B+, on its output. So ground goes to ground all around, plug + goes to regulator + and output goes to circuit plus.
or................
could connect 18V to the resistors connected to pins 1 and 6, and to regulator +, and out of regulators to the heaters, pin 4, with pin 5 to ground.
Looking at the diagram I posted on this page #2770, pin 4 is going to ground and pin 5 is getting power from the dc jack. Remove the (+) wire from pin 5 and run a wire from the out leg of the regulator to pin 5?
sure, either pin 4 or pin 5 could be positive it does not matter. so if you have it that way, connecting pin 5 to put of the voltage regulator and 4 to ground
Ok, I think the light has finally come on.
Correct me if I am wrong.....I have the LED and a wire lead to pin 5 connected to the positive on the DC jack, remove those and connect them to the leg out on the regulator.
So I wind up with negative DC jack to NEGATIVE leg of regulator, positive DC jack to IN leg of regulator, LED and Pin 5 to OUT leg of regulator.
something like this
(http://dl.dropbox.com/u/14312589/valveyheater.png)
If anyone has time, here is a link to my Diptrace and Gerber exports (with n/c drill) of a 12v valvecaster with no tone stack.
They look correct to me, but I have not built this yet. If anyone sees any issues please let me know, I do not have a good tube PCB socket, so I have not checked sizes of the one on here
fell free to use this if you think it right. Once I test and check sizes, I will have some made in a test run, I'll forward the link so anyone who wants one can just order from the board maker.
Thanks
http://dl.dropbox.com/u/14312589/ValveNoTone.zip (http://dl.dropbox.com/u/14312589/ValveNoTone.zip)
Quote from: iccaros on February 21, 2012, 06:41:59 AM
something like this
(http://dl.dropbox.com/u/14312589/valveyheater.png)
That resolved the hum issue, soooo much happier now. :icon_mrgreen:
My design: VALVE OVERDRIVE 9v (with clipping): GREAT OVERDRIVE!
(http://www.fuzzface.es/fuzzpedal/VALVE_OVERDRIVE_9V.jpg)
Gidday everybody, I've been reading and researching this project for a week or so and have managed to get one built on the breadboard, it's sure been a fun learning experience! And sounds great!
One thing that bothered me was not being able to get 12.6v to the heaters, I've built a supply using a 18v laptop supply and a 7812 regulator gave 12v...close but not close enough!
Well, I found something not sure if it's been mentioned here yet but by putting a 1N4001 between the middle pin of the regulator and ground I now get the perfect 12.6!!! Thanks to www.tube-town.net in the DIY section! They suggest using 1N4007 not sure if it's a big deal or not to replace with 1N4001 but all seems good to me....
Just noticed the last post with the clipping...gonna try that one tonight! Right after I've finished the dual-caster :icon_twisted:
Thanks to everyone that has made this project so interesting!
Got my 6111s today so looking forward to the sub-caster as well!!!!!
You can use 1n4001 or 1n4007 no big deal!
It would be if you were messing with bigger voltages and currents!
If the tube(s) draw more than 1A from your regulator then you would be in trouble! ;)
I want to have the ability to switch the C1 capacitor between values. I got a dpdt switch, soldered sockets to the outside legs to make switching easier and then connected the wire between the two middle lugs.
When I engaged the pedal the volume was a fraction of what is was before the tweak. I could hear the differences between the two values, 0.1 and 0.022uf, but again the volume was very low.
I would like the ability to switch cap values, one for single coil and the other for humbuckers. Some one stated that the 0.022uf cap was good for the humbuckers.
What did I do wrong to make the volume drop drastically?
Mod switch input cap:
(http://www.fuzzface.es/mods/mod_input_cap.jpg)
Yep that is how I had it. Removed it from the circuit and everything worked fine.
Before I removed it, I checked for cold solder joints or loose connections and I had none. It should have worked, but for so reason it did not. :icon_question:
Without the switch worked fine? because then the capacitors or the switch are bad!
Try changed the caps and the switch...
Quote from: rugeb on February 21, 2012, 06:01:51 PM
Without the switch worked fine? because then the capacitors or the switch are bad!
Try changed the caps and the switch...
Both the switch and caps are new.
I just checked capacitance with my DMM and for the 0.1 I got 0.117 and for the 0.022 I got 0.032 which looks to be within tolerance.
Any other thoughts?
is the 1m resistor from pin 2 to ground or is it on the jack like a lot of pedals. Im not positive but i think it has to be from 2 to ground.
Quote from: zambo on February 22, 2012, 12:48:57 AM
is the 1m resistor from pin 2 to ground or is it on the jack like a lot of pedals. Im not positive but i think it has to be from 2 to ground.
Zambo, I wired it PtP, so the 1M resistor is between pins 2 and 4.
Note: To clarify, the DPDT switch I am using is a ON-ON type.
My veroboard is VERIFIED.
Images:
(http://www.fuzzface.es/fuzzpedal/Valve_Overdrive-1.jpg)
(http://www.fuzzface.es/fuzzpedal/Valve_Overdrive-2.jpg)
Is there any perceivable difference between the two diagrams and the way the volume/tone are wired?
Also, I changed the gain pot value to 100K from 50K, but I am still not satisfied with the breakup. Is there anything else I can do to increase the gain? The last image shows what values I am using. I have also removed C1 and put it on a DPDT switch with a 0.022 cap so that I can use with a single coil or humbucker pickup.
(http://i622.photobucket.com/albums/tt308/reaperQ45/Valvecaster/MatsuminValveCasterWiring.gif)
(http://i622.photobucket.com/albums/tt308/reaperQ45/Valvecaster/Stratcaster.jpg)
(http://i622.photobucket.com/albums/tt308/reaperQ45/Valvecaster/Scan_Pic0001.jpg)
Can a 1n4001 be used in place of the 1n4148 on the center pin of the 7812 to bump the heater voltage from 12 to 12.6?
The heater voltage is not critical. My veroboard is VERIFIED: copy!
Another power supply (12V amp with 12AU7 + JRC386):
(http://www.beavisaudio.com/Projects/TubeCricket/TubeCricket_Final_2008.gif)
Rotary switch for input tone control:
(http://img236.imageshack.us/img236/3716/preamporangenw1.jpg)
Quote from: rugeb on February 25, 2012, 06:11:12 AM
The heater voltage is not critical. My veroboard is VERIFIED: copy!
Another power supply (12V amp with 12AU7 + JRC386):
(http://www.beavisaudio.com/Projects/TubeCricket/TubeCricket_Final_2008.gif)
Sound clips??
Hi guys - I finished my Valvecaster and it sounds great :) Thanks!
I removed the Tone control, so it's just Gain and Volume.
Here are some sound-clips, if anyone is interested: http://soundcloud.com/mwynwood/my-valve-overdrive-pedal (http://soundcloud.com/mwynwood/my-valve-overdrive-pedal)
(https://fbcdn-sphotos-a.akamaihd.net/hphotos-ak-ash4/s720x720/403056_10151337988780008_789025007_23022460_270241075_n.jpg)
Hello guys :)
i came a cross this cool project and i have some questions..
1 - can i use any 12AU7 TUBE? for example... can i use this one : http://www.ebay.com/itm/2x-NEW-JJ-Tesla-12AU7-ECC82-Vacuum-Tubes-Matched-Pair-TESTED-/290626797687?pt=Vintage_Electronics_R2&hash=item43aab50077#ht_1127wt_1164
or... this : http://www.ebay.com/itm/TUBE-AMP-PREAMP-DAMPERS-12AX7-12AU7-12AT7-ECC83-EL84-6922-EL84-5751-5687-/350539278417?pt=Vintage_Electronics_R2&hash=item519dc4e851#ht_4357wt_1397
sorry for the noob question, i dont know or understand in tubes.. :icon_redface:
2 - does any of you guys maybe connect the Valve Caster to a synth? (i want it more for synth )
3 - does this circuit can run on 12V DC without changing anything?
4 - does the TUBE lighted up :icon_eek:
thanks in advance :icon_smile:
Sincerely,
Isak E.
1) first link is for 2 coupled tubes, second link is for the ring dampers. You don't need ring dampers, you need one tube.
2) Not that I know. But it can be used at the place of your ordinary preamp if you use one.
3) Read the whole thread
4) Read the whole thread
thank you for your reply friend :)
1 i didnt see that the second link is ring dampers, sorry about that.
2 so it can be use as a preamp haaa...?
3 - 4 excuse me sir, why i need to read the whole thread (141 pages, just a reminder) if you know the answer? i'm sure you probable answered this questions a 10000000 times, but hey....you are here for this purpose, or i'm wrong?
i think the whole idea behind a forum is to help people.
i'm sorry if i bothered you with my questions.
i will not ask again and no hard feelings.
Sincerely,
Isak E.
I read this thread a while ago (when it was about 130 pages) so my memory isn't perfect, but I think the answers are: it depends. The circuit should work on 12V, just make sure the caps are rated at least at 24V. And if the tube doesn't light up enough, stick a LED in the socket. Most answers are in the first few pages, I think.
Renegadrian is a great guy and he's always helpful but, as you say, he's answered 10000000 times.
Edit: glow: post #12; 12V: just about everywhere (yes, it works).
Pollinator95 thank you for replying.
i know he is a great guy, i "read" almost half way and see how he helped people, but man 141 pages!?!?!?!?!?!?
in any way i will never do that to no one even if i answered million times, if the thread is long as the universe of course.
i dont have nothing against him he actually helped me even without him knowing that and i thank him for that!!!
i hope it will sound good with synth's :icon_twisted:
Renegadrian...thank you!
Pollinator95 thank you again.
Sincerely,
Isak E.
Quote from: mwynwood on February 26, 2012, 05:50:58 AM
Hi guys - I finished my Valvecaster and it sounds great :) Thanks!
I removed the Tone control, so it's just Gain and Volume.
Here are some sound-clips, if anyone is interested: http://soundcloud.com/mwynwood/my-valve-overdrive-pedal (http://soundcloud.com/mwynwood/my-valve-overdrive-pedal)
(https://fbcdn-sphotos-a.akamaihd.net/hphotos-ak-ash4/s720x720/403056_10151337988780008_789025007_23022460_270241075_n.jpg)
*****************************
= VERY COOL - CONGRATULATIONS! =
*****************************
Don't get JJ 12au7 tubes for a 12v valvecaster, they don't work very well at low voltages.
Quote from: juansolo on February 26, 2012, 01:54:48 PM
Don't get JJ 12au7 tubes for a 12v valvecaster, they don't work very well at low voltages.
thank you for pointing this out, what do you suggest?
Quote from: Isak on February 26, 2012, 12:31:21 PM
Pollinator95 thank you for replying.
i know he is a great guy, i "read" almost half way and see how he helped people, but man 141 pages!?!?!?!?!?!?
in any way i will never do that to no one even if i answered million times, if the thread is long as the universe of course.
i dont have nothing against him he actually helped me even without him knowing that and i thank him for that!!!
i hope it will sound good with synth's :icon_twisted:
Renegadrian...thank you!
Pollinator95 thank you again.
Sincerely,
Isak E.
Isak:
It took me a week to read all 140 pages, but I came away with a wealth of information and knowledge about this little project. The search function can and is your friend. Also the high points of this single tube VC has been summarized in pdf form by one of the members, there are two of them, make sure you download the second as a couple of errors were corrected with the second version.
Another suggestion would be to create a word document and cut/paste pertinent information, such as mods and any information related to using a 12V power supply.
Most if not all your questions will be answered in this thread.
I would recommend building the single valve with/without the Tone pot first before attempting the dual tube build. You also have the option of building the VC with all the major components soldered directly on the tube socket, which I did, or on vero board.
Good luck and happy building.
texstrat
thank you, this is what i'm trying to do now im on page 57 :icon_confused:
and i still dont know what tube to order from ebay...
they have a lot.
what tube did you used?
Quote from: Isak on February 26, 2012, 06:22:45 PM
texstrat
thank you, this is what i'm trying to do now im on page 57 :icon_confused:
and i still dont know what tube to order from ebay...
they have a lot.
what tube did you used?
I did not see anything on page 57, but this is the schematic I used and it does work.
(http://i622.photobucket.com/albums/tt308/reaperQ45/Valvecaster/Scan_Pic0001.jpg)
I used a generic 12V 700mA power supply. Anything rated over 200mA will be fine. Make sure to switch the power tip so that the outer sleeve is (+) and the inner part of the barrel is (-). Is is also important to include a voltage regulator on the DC jack; otherwise, you will get a lot of hum.
The switch that is drawn in allows you to cut the bass, it acts like a boost.
As to tubes, I like the way the 12ua7a, 12ax7 and 12at7 work. Each gives the effect a distinctly different tone. Here is a quote from another member about the different tubes @12V
"12ax7 no real gain.. ok.. but no boost..
12au7 good boost, when gain maxed really farts out.
12u7 -- good sounding, mod gain, no difference adding more voltage.
12at7 -- more distortion (good in my eyes)
ECC99 .. my GOD... best sounding for me.. Good distortion, turn down to "warm" overdrive.. lots of boost, would not turn master volume past 1/4
5751 -- Good sounding low boost, nice warm overdrive but bad when gain turned more than 75%"
One note about the attached image, pin 3 (Vout) on the 7812 voltage regulator does not go to lug 4 of the foot switch. Remove the two wire leads from the DC jack and solder those to pin 3.
I also took C1 going to pin 2 of the tube and in place put a on-on DPDT switch in to try different capacitor values. I play both single coil and humbucker guitars and found that a 0.1uf cap works better with the single coil and the 0.22uf sounds better with the humbuckers.
Hope this helps.
I just finished reading all 141 pages AND finishing my Valvecaster! It is a mostly stock 12AU7 unit running @ 12V, 4 position cap selector on the input, 2.2nf cap across the gain pot, a switch to exclude the tone circuit, and a trim pot substituting for R2. I adjusted the trim to give a clean boost at low volume and minimum gain. I get a nice overdrive by turning up the volume and gain pots. Thanks to all of you folks for the massive wealth of information on this thread!
thanks for the info texstrat .
i meant that i'm reading on page 57 and keep on reading now on page 86 :icon_wink:
i'm actually looking for the bass sound :)
i'm not a guitar player, i'm a synthesizer/keyboards player.
i'm assembling an analog filter (korg ms20 based) and i wanted to put on the audio path an overdrive to get warm bassy sound after the filter.
then i searched the net for overdrives and i came a cross this amazing tube based overdrive.
i found on tube this cool vid of the valvecaster vs x0xb0x http://www.youtube.com/watch?v=wITCU1xOFMI
i dont want the sound to be boosty only to give it character (sound reasonable?)
i guess i will need to to run some tests after assembling the valvecaster.
any of you guys maybe have an analog synth and can tell me how its sounds after connecting the valvecaster to the synth?
cheers,
Isak E.
3)while the title of this topic says it runs on a 9v battery, it is almost mandatory to use a wall wart (heaters do suck lots of current) and run on 12V to follow the heaters specs (it should be 12.6V but it's ok at 12V) - basically you can wire it in two different ways, 12V feeding the whole circuit or 12V to heaters and more V to the plates
4) every tube is different, it goes from a barely lit spark to a nice orange glow.
Isak, didn't want to be rude, yeah I answered to the same questions more than once, but it's ok every time.
Meanwhile your questions got answers, it is strongly suggested to read everything on the topic, as texstrat points out.
I know it takes time, but it will give you more knowledge about it.
Else, just take the layout from beano at the very first page of the topic and go thru - it'll work just the same!
hi Renegadrian.
thank you for everything.
i think you should summery all the important things of this cool project to one post, dont you think?
some one did it a long the way of this endless thread ..
the next quote and everything on page 141 is more then enough for the project.
QuotePossible improvement, depending on context:
"I note that the original schematic and layout specify that the triode at pins 1-3 be used for the voltage gain stage, and 6-8 for the follower.
This isn't usually the best way to do it with a 12A*7. With battery power or regulated DC going through the heaters, it doesn't matter which triode you use in which position, but if you're using AC or less-than-pristine DC, the triode at pins 6-8 will be quieter, due to the location of the heater pins on the tube. (You can find mention of this in the data sheets on many 12A*7 series tubes.)"
"I lower the coupling cap between stages for less bass."
"For lowering bass, you could try lowering the value of either the input cap, or the coupling cap between the two tube stages."
"I am bypassing the Valvecaster gain pot with a 2.2nf cap. This helps maintain some brightness when the VC gain is turned down. For the input cap on the Valvecaster I am using a combination of caps to give me 2.7nf. This helps tighten up the bottom end."
"To tame the gain I would lower R2 and R3. 220k and 100k seem pretty high for a low voltage circuit. Even in a regular high voltage amp the normal value is just 100k. So maybe cut them in half."
"if you bring down that 220k to 100k it will def lower the gain a bit. I built mine with both plate r's at 100k."
"A 1M gain pot allows massive, saturated gain. A little mushy in the bass frequencies, but pretty cool. I'm considering putting a "more" switch in, whereby it adds a resistor in series to the regular gain pot."
"Adding resistance to the plate resistors(R1 and R2) will increase gain. Adding resisitance to VR1, in series with the gain pot, will decrease gain."
"guitarx: replace the 100k resistor with 47k. Replace the 220k resistor with 100k. Beautiful cleans."
"To fellow Valvecaster experimenters -- I've currently got this circuit on a breadboard, switching out everything and I have some items of interest to report, especially for those looking for more gain.
The nicest clean sound I've found so far, is with the following mods:
R2 = 100k
R3 = 47k
C1 = 0.1uf
Remove C4 and VR2"
ecc82 electro harmonix = perfect sound as expected
ecc82 electro harmonix gold pin = less gain
gt 12ax7a = bad
sovtek 12ax7 = bad
gt 12ax7wc = little overdrive and gain but good sound
vintage ei yugoslavia 12ax7 = lots of gain and harmonics
put a 100uF cap across the DC jack (positive leg to positive rail, neg. leg to neg. rail), then, instead of connecting the positive rail directly to the circuit, connect it to the regulator's pin1, ground to pin2, and the circuit to pin3. Then screw it on the enclosure. It is a 7812.
do yaa have anything to add?
:icon_smile:
anyway...
wanted to ask please...
can you recommend/advice me on what brand of caps to use for this project?
if you have a link for me to order from it will be great.
I WANT TO START THIS PROJECT VERY MUCH!!!! :icon_cool:
thank again
Isak E.
Quote from: rugeb on February 25, 2012, 06:41:37 AM
Rotary switch for input tone control:
(http://img236.imageshack.us/img236/3716/preamporangenw1.jpg)
Hey...
good one however i thought that the 68k resistor that the signal of a passive instrument faces drops the volume right?
Won't this lead to less gain? ???
I mean the ''stock'' circuit doesn't have that resistor.
Renegradian wrote: 12v for heaters or 12,6v... is true! but is not critical, heaters and plates on 9v works well with 12AU7 tube.
My veroboard (pg.140) it's verified, assembled and tested at 9v: the sound is very nice.
Quote from: tasos on February 27, 2012, 12:35:56 PM
Quote from: rugeb on February 25, 2012, 06:41:37 AM
Rotary switch for input tone control:
(http://img236.imageshack.us/img236/3716/preamporangenw1.jpg)
Hey...
good one however i thought that the 68k resistor that the signal of a passive instrument faces drops the volume right?
Won't this lead to less gain? ???
I mean the ''stock'' circuit doesn't have that resistor.
It's not verified yet, look only rotary switch circuit with capacitors.
* Yeah 9V will work but I noticed that making it work at the right voltage gives you a better sound, I think I like 12V (I use it on all pedals now) and you can get some 12V adapter for very cheap - I got one 1A and one 3A and they do the work!
* Isak, the kind of capacitors you are going to use is not that critical, as in a lot of pedals anyway (IMPO). I like ceramics (that a lot of people hate) or WIMAs (the red ones)
* I don't know if both a 68k resistor and (switchable) cap(s) cut too much sound at the input - actually I'd leave out one of those components.
Many pedals work better at 12V, but others (fuzz type) require less than 9v (battery low).
You're right that the tube overdrive 12V would be ok, but for a beginners is easy at 9v (the same volts for all pedals).
Quote from: Isak on February 26, 2012, 02:08:41 PM
Quote from: juansolo on February 26, 2012, 01:54:48 PM
Don't get JJ 12au7 tubes for a 12v valvecaster, they don't work very well at low voltages.
thank you for pointing this out, what do you suggest?
I tried three different 12au7 tubes in mine before it sounded right:
1: JJs sounded terrible crunchy and harsh
2: Electro Harmonix sounded ehh better but not what I wanted
3: An older RCA 12au7a labeled lowrey organs...sounds amazing much smoother break up.
I run mine at 9v and it works fine. At 12v you do get more boost and more headroom. Pedal is just what I am looking for at 9v though I dont need any more headroom out of it and you get plenty of boost at 9v.
Hope this helps!
Dana
Quote from: danamoose on February 28, 2012, 09:31:23 PM
Quote from: Isak on February 26, 2012, 02:08:41 PM
Quote from: juansolo on February 26, 2012, 01:54:48 PM
Don't get JJ 12au7 tubes for a 12v valvecaster, they don't work very well at low voltages.
thank you for pointing this out, what do you suggest?
I tried three different 12au7 tubes in mine before it sounded right:
1: JJs sounded terrible crunchy and harsh
2: Electro Harmonix sounded ehh better but not what I wanted
3: An older RCA 12au7a labeled lowrey organs...sounds amazing much smoother break up.
I run mine at 9v and it works fine. At 12v you do get more boost and more headroom. Pedal is just what I am looking for at 9v though I dont need any more headroom out of it and you get plenty of boost at 9v.
Hope this helps!
Dana
Pretty much matches our thoughts. The RCA cleartops are about the best compromise of tone vs current draw that we've found. Best sounding of all that we've used was a Brimar 12BH7, but pulls twice the current and is much bigger.
Quote* Isak, the kind of capacitors you are going to use is not that critical, as in a lot of pedals anyway (IMPO). I like ceramics (that a lot of people hate) or WIMAs (the red ones)
i ordered wima's polypropylene ones, thanks :icon_wink:
Quote1: JJs sounded terrible crunchy and harsh
2: Electro Harmonix sounded ehh better but not what I wanted
3: An older RCA 12au7a labeled lowrey organs...sounds amazing much smoother break up.
QuotePretty much matches our thoughts. The RCA cleartops are about the best compromise of tone vs current draw that we've found. Best sounding of all that we've used was a Brimar 12BH7, but pulls twice the current and is much bigger.
thank you guys.
i actually bought 3 from ebay.
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=260951669480&ssPageName=ADME:L:OC:US:1123#ht_500wt_1180
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=230751585117&ssPageName=ADME:L:OC:US:1123#ht_708wt_1396
http://cgi.ebay.com/ws/eBayISAPI.dll?ViewItem&item=290664027678&ssPageName=ADME:L:OC:US:1123#ht_1127wt_1163
i will try all 3 of them to see what i like the most.
i have a professional question.. (maybe its to late to ask cause i bought all the stuff i need to assemble this amazing project :icon_mrgreen: )
can i use this as a sound warmer?
i mean..
not to extremely overdrive the sound, only a "bit", to give the sound fatness (know what i mean?) a bit more crispy and warm sound.
just a reminder, its going to be for a synth, not guitar.
thanks in advance for your answers.
cheers,
Isak E.
Yes! I used it a lot with my bass to fatten the sound, it does add a lot of warmth without going dirt (obviously not at full tilt) boosting all frequencies in a transparent yet "tubier" way...
Quote
can i use this as a sound warmer?
i mean..
not to extremely overdrive the sound, only a "bit", to give the sound fatness (know what i mean?) a bit more crispy and warm sound.
Yes this is exactly what I get when I turn the gain on the pedal all the way down. It adds as much volume as you want with just a touch of dirty.
-Dana
thanks guys, i'm so excited :icon_mrgreen:
another question if i may please...
i ask you cause your guys all ready into pedal boxes and so..
where can i get nice big aluminium enclosure for this project?
i need something like this http://www.ebay.com/itm/Tube-Amp-Chassis-DIY-12-8x7-1x2-3-Aluminum-Project-Enclosure-Stereo-Amp-Preamp-/250932265782?pt=Vintage_Electronics_R2&hash=item3a6cba8336#ht_739wt_1396
but not this crazy cost :o
cheers,
Isak E.
You could make one? ;)
Quote from: Isak on March 01, 2012, 01:57:52 AM
thanks guys, i'm so excited :icon_mrgreen:
another question if i may please...
i ask you cause your guys all ready into pedal boxes and so..
where can i get nice big aluminium enclosure for this project?
i need something like this http://www.ebay.com/itm/Tube-Amp-Chassis-DIY-12-8x7-1x2-3-Aluminum-Project-Enclosure-Stereo-Amp-Preamp-/250932265782?pt=Vintage_Electronics_R2&hash=item3a6cba8336#ht_739wt_1396
but not this crazy cost :o
cheers,
Isak E.
=========================
For this project eBay search: 1590BB
=========================
Or tayda....
ain't that bad for about 9bucks including shipping
Hi everyone,
im new here and also in DIY but i managed to make some pedals by carrefuly reading all your advice here.
Also finished the ValveMaster which is amazing but even if i tried to bias it a bit differently i didnt manage to take out of it a totaly clean sound.
There is always a bit of dirt even with all the gain down.
Is there any way to remove all "dirt" from that great pedal?
(congrats for your forum again)
Chris
QuoteYou could make one? ;)
i wish i had time for it. :-[
QuoteFor this project eBay search: 1590BB
thanks but its too small i'm afraid.
A 1590BB has 110x84x34 it will be more than enough if you mill a hole for the valve. Even if you want to put the valve inside the enclosure it will fit if you place it horizontaly (you need 24mm and have 27.75).
My project with 1590BB:
(http://fuzzface.es/fuzzpedal/especiales/Valve-Ovedrive-9v.gif)
thank you for your good advice's.
guys i'll be making few effects in one box, like a multi-effect for synth.
this is the knobs i'll be using... (the out base is 4.5cm)
(http://i41.tinypic.com/250ig5d.jpg)
so the 1590BB wont do, sorry.
thanks guys.
:icon_lol: ha, ha, ha....., of course!
Thanks to all for the extensive work on this great little circuit!
Yesterday I breadboarded the stock Valvecaster from Dano Beavis' schematic, and it sounds pretty damn good.
If you have a minute, read my progress in the search for the ultimate low gainer.
Previously I was using a Paul C. Tim for my low gain needs, but I run a 50w Plexi set to absolute clean, but loud. Zero breakup from the amp, so I felt that the Tim, while brilliant when combined with a bit of amp dirt, was not the pedal for me. So I got a vintage Marshall Bluesbreaker pedal. Again, great pedal particularly with mid scooped amps like a Fender Twin, but the Plexi has it's share of mids in its' natural tone, and the Bluesbreaker pedal/Plexi amp combo is a little too boxy in the mids for me.
I ran the Valvecaster on the breadboard through my Plexi and it's very good. I was lucky enough to receive 4 vintage 1950's 12AU7's out of an old Baldwin organ, courtesy of one of the wonderful BYOC forum members. However, as noted, being that the circuit is optimised for single coils, with my humbucking guitars there was just WAY too much bass, bordering into soft farty fuzz territory in the low end. Not good. I wound all the bass out of the amp, and got a great rocking Malcom Young sound.
I have been comparing the JuanSolo/Cleggy Boobtube schematic against Rick Holt's Valvemaster schematic, and I believe Rick's mods could be quite an improvement on the intial Matsumin design.
Having the gain pot after the first Valve stage (here in Australia we call 'tubes' "Valves") seems to make sense to me in that it allows the circuit to ramp up it's total gain level before bringing it down, as opposed to bleeding signal to ground from the get go.
Today I will make some modifications to the Valvecaster circuit on the breadboard, and aim to do the following:
1) Work out if dropping the input cap OR the coupling cap (both 47n in the initial schemo) to a lower value is better for removing unwanted low end frequencies. I'm imagining that I'll be putting that component on a switch to work for SC's/HB's as the need arises. The JuanSolo/Cleggy circuit uses a 10n for HB guitars, so I'll try that.
2) I want to hit the circuit with various voltages. Right now it's pulling 9v straight out of a 1-Spot. I use a Cioks AC10 for my main board, and I believe I have a 9v, 12v and 18v tap free on the powersupply.
Before I get into this, I see on the JuanSolo/Cleggy schematic that there is 12v going to Pin 5 of the valve, while 23v goes to Pins 1 and 6 of the valve. I have read the thread pretty extensively, so may have missed the answer if it already exists, but what are the sonic benfits of sending different voltages to different Pins of the valve? (I have done a lot of DIY pedals with transistors, FETS, opamps etc..., this is my first valve circuit). Question - Can I just try different voltages to the whole circuit, eg: 9v, 12v, 15v, 18v, 24v? Or can only one part of the valve only be fed with 9v, while other parts of the valve can take higher voltages?
I have a great hammertone Pedalenclosures enclosure to use for this project. I plan to have the valve up back in some kind of protective rail, and to rock the sh*t out of this thing. If it works well, then I hope this does my low to medium gain tones for me. My medium to high gainer is a Kingsley Minstrel, and man that pedal is off the hook. So, another valve pedal to pair with it seems like the go.
Thanks for reading, any answers to my question would be great, and I will post pics once I'm done.
Cheers!
Quote from: candletears7 on March 03, 2012, 07:52:40 PM
2) I want to hit the circuit with various voltages. Right now it's pulling 9v straight out of a 1-Spot. I use a Cioks AC10 for my main board, and I believe I have a 9v, 12v and 18v tap free on the powersupply.
Before I get into this, I see on the JuanSolo/Cleggy schematic that there is 12v going to Pin 5 of the valve, while 23v goes to Pins 1 and 6 of the valve. I have read the thread pretty extensively, so may have missed the answer if it already exists, but what are the sonic benfits of sending different voltages to different Pins of the valve? (I have done a lot of DIY pedals with transistors, FETS, opamps etc..., this is my first valve circuit). Question - Can I just try different voltages to the whole circuit, eg: 9v, 12v, 15v, 18v, 24v? Or can only one part of the valve only be fed with 9v, while other parts of the valve can take higher voltages?
you replied to your own question man! The heaters (pins 4-5) must be fed to 9 or better 12v. that's mandatory, you dont want to blow a tube!!! The other parts would benefit of more voltage! tubes were usually intended to run on high voltage, and you can read a lot of their curves thru their datasheets - low voltage experiments are quite unknown (we can say we are the piooniers of that...) so we can just argue the behaviour at low voltage...the main benefits of higher voltage at the anodes
is that you feed more "air" - also some 12ax7 can react better.
I was wandering what the simplest voltage boost circuit is to get the 9v from a boss adapter up to 12v for the heaters?
also, has anyone tried this circuit with a 9au7? from what I have read it is the same as the 12au7 except the heater runs on 4.5v/9v instead of 6v/12v
and I would just like to share this incredibly clean build that I found on the net http://www.flickr.com/photos/timpatterson/5518405003/in/photostream/
Well here it is, finally got it stuffed in the 125B box. Running on 12V and using a 12ua7a RCA tube. Went with a Sci-Fi theme :icon_mrgreen:
(http://i622.photobucket.com/albums/tt308/reaperQ45/Valvecaster/DSC07829.jpg)
(http://i622.photobucket.com/albums/tt308/reaperQ45/Valvecaster/DSC07830.jpg)
(http://i622.photobucket.com/albums/tt308/reaperQ45/Valvecaster/DSC07831.jpg)
No big difference,I made on with 9au7. my tube seemed to lack some volume, it sounded a lil more compressed and a lil weaker - but it could the tube I used...
---------------------
texstrat, you pedal looks killer!!!
Thanks, it has been a fun build. I am now trying to figure out what to build next. I think I am going to build another ruby 0.5 watt amp in an Altoids tin.
altoids amps are cool!!
Thanks mate! I just didn't know if different voltages had to be fed to different pins. I'll experiment with hitting the whole shebang with higher voltages. I don't want to get into anything more than medium gain, I have the Minstrel for that. If this puts out a nice fat AC/DC sound at most I'll be happy.
And while we're here, a big thankyou to you personally for your layouts you've done in the past. When I was just getting into DIY and building vero layouts, I came across yours and used them on a couple builds - so cheers! :)
Quote from: Renegadrian on March 03, 2012, 08:50:05 PM
you replied to your own question man! The heaters (pins 4-5) must be fed to 9 or better 12v. that's mandatory, you dont want to blow a tube!!! The other parts would benefit of more voltage! tubes were usually intended to run on high voltage, and you can read a lot of their curves thru their datasheets - low voltage experiments are quite unknown (we can say we are the piooniers of that...) so we can just argue the behaviour at low voltage...the main benefits of higher voltage at the anodes
is that you feed more "air" - also some 12ax7 can react better.
Texstrat what functions do your switches control? One looks to be negative feedback, and can't tell on the other one. thanks!
The boost switch is a negative feedback and the other is a lite - dark switch replacing C1. I used a DPDT switch with a 0.1uf and 0.022uf.
Quote from: candletears7 on March 03, 2012, 07:52:40 PM
Thanks to all for the extensive work on this great little circuit!
Yesterday I breadboarded the stock Valvecaster from Dano Beavis' schematic, and it sounds pretty damn good.
If you have a minute, read my progress in the search for the ultimate low gainer.
Previously I was using a Paul C. Tim for my low gain needs, but I run a 50w Plexi set to absolute clean, but loud. Zero breakup from the amp, so I felt that the Tim, while brilliant when combined with a bit of amp dirt, was not the pedal for me. So I got a vintage Marshall Bluesbreaker pedal. Again, great pedal particularly with mid scooped amps like a Fender Twin, but the Plexi has it's share of mids in its' natural tone, and the Bluesbreaker pedal/Plexi amp combo is a little too boxy in the mids for me.
I ran the Valvecaster on the breadboard through my Plexi and it's very good. I was lucky enough to receive 4 vintage 1950's 12AU7's out of an old Baldwin organ, courtesy of one of the wonderful BYOC forum members. However, as noted, being that the circuit is optimised for single coils, with my humbucking guitars there was just WAY too much bass, bordering into soft farty fuzz territory in the low end. Not good. I wound all the bass out of the amp, and got a great rocking Malcom Young sound.
I have been comparing the JuanSolo/Cleggy Boobtube schematic against Rick Holt's Valvemaster schematic, and I believe Rick's mods could be quite an improvement on the intial Matsumin design.
Having the gain pot after the first Valve stage (here in Australia we call 'tubes' "Valves") seems to make sense to me in that it allows the circuit to ramp up it's total gain level before bringing it down, as opposed to bleeding signal to ground from the get go.
Today I will make some modifications to the Valvecaster circuit on the breadboard, and aim to do the following:
1) Work out if dropping the input cap OR the coupling cap (both 47n in the initial schemo) to a lower value is better for removing unwanted low end frequencies. I'm imagining that I'll be putting that component on a switch to work for SC's/HB's as the need arises. The JuanSolo/Cleggy circuit uses a 10n for HB guitars, so I'll try that.
2) I want to hit the circuit with various voltages. Right now it's pulling 9v straight out of a 1-Spot. I use a Cioks AC10 for my main board, and I believe I have a 9v, 12v and 18v tap free on the powersupply.
Before I get into this, I see on the JuanSolo/Cleggy schematic that there is 12v going to Pin 5 of the valve, while 23v goes to Pins 1 and 6 of the valve. I have read the thread pretty extensively, so may have missed the answer if it already exists, but what are the sonic benfits of sending different voltages to different Pins of the valve? (I have done a lot of DIY pedals with transistors, FETS, opamps etc..., this is my first valve circuit). Question - Can I just try different voltages to the whole circuit, eg: 9v, 12v, 15v, 18v, 24v? Or can only one part of the valve only be fed with 9v, while other parts of the valve can take higher voltages?
I have a great hammertone Pedalenclosures enclosure to use for this project. I plan to have the valve up back in some kind of protective rail, and to rock the sh*t out of this thing. If it works well, then I hope this does my low to medium gain tones for me. My medium to high gainer is a Kingsley Minstrel, and man that pedal is off the hook. So, another valve pedal to pair with it seems like the go.
Thanks for reading, any answers to my question would be great, and I will post pics once I'm done.
Cheers!
Add a voltage doubler: 9v to heater, 18v to plates.
(http://www.fuzzface.es/mods/VD9-18.jpg)
Use a LTC1054 to get 0,5 mA instead of the 0,1mA an ICL7660S can handle.
Quote from: rugeb on March 04, 2012, 04:31:14 AM
Quote from: candletears7 on March 03, 2012, 07:52:40 PM
Thanks to all for the extensive work on this great little circuit!
Yesterday I breadboarded the stock Valvecaster from Dano Beavis' schematic, and it sounds pretty damn good.
If you have a minute, read my progress in the search for the ultimate low gainer.
Previously I was using a Paul C. Tim for my low gain needs, but I run a 50w Plexi set to absolute clean, but loud. Zero breakup from the amp, so I felt that the Tim, while brilliant when combined with a bit of amp dirt, was not the pedal for me. So I got a vintage Marshall Bluesbreaker pedal. Again, great pedal particularly with mid scooped amps like a Fender Twin, but the Plexi has it's share of mids in its' natural tone, and the Bluesbreaker pedal/Plexi amp combo is a little too boxy in the mids for me.
I ran the Valvecaster on the breadboard through my Plexi and it's very good. I was lucky enough to receive 4 vintage 1950's 12AU7's out of an old Baldwin organ, courtesy of one of the wonderful BYOC forum members. However, as noted, being that the circuit is optimised for single coils, with my humbucking guitars there was just WAY too much bass, bordering into soft farty fuzz territory in the low end. Not good. I wound all the bass out of the amp, and got a great rocking Malcom Young sound.
I have been comparing the JuanSolo/Cleggy Boobtube schematic against Rick Holt's Valvemaster schematic, and I believe Rick's mods could be quite an improvement on the intial Matsumin design.
Having the gain pot after the first Valve stage (here in Australia we call 'tubes' "Valves") seems to make sense to me in that it allows the circuit to ramp up it's total gain level before bringing it down, as opposed to bleeding signal to ground from the get go.
Today I will make some modifications to the Valvecaster circuit on the breadboard, and aim to do the following:
1) Work out if dropping the input cap OR the coupling cap (both 47n in the initial schemo) to a lower value is better for removing unwanted low end frequencies. I'm imagining that I'll be putting that component on a switch to work for SC's/HB's as the need arises. The JuanSolo/Cleggy circuit uses a 10n for HB guitars, so I'll try that.
2) I want to hit the circuit with various voltages. Right now it's pulling 9v straight out of a 1-Spot. I use a Cioks AC10 for my main board, and I believe I have a 9v, 12v and 18v tap free on the powersupply.
Before I get into this, I see on the JuanSolo/Cleggy schematic that there is 12v going to Pin 5 of the valve, while 23v goes to Pins 1 and 6 of the valve. I have read the thread pretty extensively, so may have missed the answer if it already exists, but what are the sonic benfits of sending different voltages to different Pins of the valve? (I have done a lot of DIY pedals with transistors, FETS, opamps etc..., this is my first valve circuit). Question - Can I just try different voltages to the whole circuit, eg: 9v, 12v, 15v, 18v, 24v? Or can only one part of the valve only be fed with 9v, while other parts of the valve can take higher voltages?
I have a great hammertone Pedalenclosures enclosure to use for this project. I plan to have the valve up back in some kind of protective rail, and to rock the sh*t out of this thing. If it works well, then I hope this does my low to medium gain tones for me. My medium to high gainer is a Kingsley Minstrel, and man that pedal is off the hook. So, another valve pedal to pair with it seems like the go.
Thanks for reading, any answers to my question would be great, and I will post pics once I'm done.
Cheers!
Add a voltage doubler: 9v to heater, 18v to plates.
(http://www.fuzzface.es/mods/VD9-18.jpg)
Use a LTC1054 to get 0,5 mA instead of the 0,1mA an ICL7660S can handle.
would this one work http://australia.rs-online.com/web/p/charge-pump/0526763/
just asking cause it says output voltage is -5 on the page?
Quote from: rugeb on March 04, 2012, 04:31:14 AM
Use a LTC1054 to get 0,5 mA instead of the 0,1mA an ICL7660S can handle.
I believe you meant to say "Use the LT1054 to get 0,1mA."
The 1054 can only handle up to 100mA.
Unless you can link to the LT"
C"1054. I could not find this.
Use LT1054:
9v input => 18v output
12v input => 24v output
Yes, the LT1054 can only handle up to 100mA.
See post: http://www.diystompboxes.com/smfforum/index.php?topic=60871.0 (http://www.diystompboxes.com/smfforum/index.php?topic=60871.0)
-------------------------------------------
Another voltage doubler with 555 (up to 200mA):
(http://fuzzface.es/mods/VD555.gif)
EDIT:
For 18v testing, a easy solution: :icon_idea:
(http://www.fuzzface.es/mods/9+9_18.jpg)
Quote from: texstrat on March 03, 2012, 09:38:00 PM
Well here it is, finally got it stuffed in the 125B box. Running on 12V and using a 12ua7a RCA tube. Went with a Sci-Fi theme :icon_mrgreen:
(http://i622.photobucket.com/albums/tt308/reaperQ45/Valvecaster/DSC07829.jpg)
where did you get that heat sink? that is nice and small with lots of fins.
Had a wicked hum in my valvy, didn't matter what PS I used or where in the house I was using it. I simply added a 7812 rectifier with (2) 220uF caps (one from the dc jack to ground, the other from power out to ground) and my valvy is SILENT. Dead silent. I just thought I'd throw that out there in case anyone else was having an issue.
Quote from: iccaros on March 04, 2012, 11:31:22 PM
Quote from: texstrat on March 03, 2012, 09:38:00 PM
Well here it is, finally got it stuffed in the 125B box. Running on 12V and using a 12ua7a RCA tube. Went with a Sci-Fi theme :icon_mrgreen:
(http://i622.photobucket.com/albums/tt308/reaperQ45/Valvecaster/DSC07829.jpg)
where did you get that heat sink? that is nice and small with lots of fins.
Steve:
I bought them on Ebay for another project and thought they might fit, they did. If you are interested, I can dig up the box and let you know who manufactured them.
Thanks for that, rugeb!
:icon_wink:
Quote from: candletears7 on March 03, 2012, 10:40:38 PM
...a big thankyou to you personally for your layouts you've done in the past. When I was just getting into DIY and building vero layouts, I came across yours and used them on a couple builds - so cheers! :)
Wow so nice to read such nice words...I am so pleased when someone appreciates my layouts and uses them with good results!!!
Quote from: runmikeyrun on March 04, 2012, 11:52:48 PM
Had a wicked hum in my valvy, didn't matter what PS I used or where in the house I was using it. I simply added a 7812 rectifier with (2) 220uF caps (one from the dc jack to ground, the other from power out to ground) and my valvy is SILENT. Dead silent. I just thought I'd throw that out there in case anyone else was having an issue.
Ok runmikeyrun: Tested! ;)
Now, the schematic:
(http://www.fuzzface.es/mods/HumReducer.jpg)
Quote from: Renegadrian on March 05, 2012, 09:13:47 AM
Quote from: candletears7 on March 03, 2012, 10:40:38 PM
...a big thankyou to you personally for your layouts you've done in the past. When I was just getting into DIY and building vero layouts, I came across yours and used them on a couple builds - so cheers! :)
Wow so nice to read such nice words...I am so pleased when someone appreciates my layouts and uses them with good results!!!
I'm also a follower of Renegadrian...
Adriano: from Spain, thanks for all! ;)
Quote from: rugeb on March 05, 2012, 12:13:45 PM
Quote from: runmikeyrun on March 04, 2012, 11:52:48 PM
Had a wicked hum in my valvy, didn't matter what PS I used or where in the house I was using it. I simply added a 7812 rectifier with (2) 220uF caps (one from the dc jack to ground, the other from power out to ground) and my valvy is SILENT. Dead silent. I just thought I'd throw that out there in case anyone else was having an issue.
Ok runmikeyrun: Tested! ;)
Now, the schematic:
(http://www.fuzzface.es/mods/HumReducer.jpg)
Right hand side cap is backwards.
Quote from: kurtlives on March 05, 2012, 12:50:06 PM
Quote from: rugeb on March 05, 2012, 12:13:45 PM
Quote from: runmikeyrun on March 04, 2012, 11:52:48 PM
Had a wicked hum in my valvy, didn't matter what PS I used or where in the house I was using it. I simply added a 7812 rectifier with (2) 220uF caps (one from the dc jack to ground, the other from power out to ground) and my valvy is SILENT. Dead silent. I just thought I'd throw that out there in case anyone else was having an issue.
Ok runmikeyrun: Tested! ;)
Now, the schematic:
(http://www.fuzzface.es/mods/HumReducer.jpg)
Right hand side cap is backwards.
Yes, physically... of course!, but the negative (ground) it's marked: WITH GREEN TRACE to avoid problems.
O_O.... it took three days... I may very well have failed a Class... but damn it I've read the whole thread.
and ordered some tubes which should get here soon... having never done anything like this, my mind keeps changing in what I'm making but due to a recent changing of tubes in my blackstar amp and pedal I've got some extra tubes anyway...
Since I've never done this before and I'm always one to shot for the moon... why not try my hand at a triple master... and have each section true bypassed... also maybe a master true-by-pass for the second and third section. Run the whole thing as hot(volts on plates wise) as reasonable(12.6 to 25.2) volts... Cut the ton pots for (3)(switches bass-cut/flat/treble-cut) and hope that it will give me enough options to keep things from sounding flubby...
Of Course will have to get a good PS... probably something with more than 12.6vDC then regulate it down for the heaters and send the rest on to the circuit. running three of them will mean I should need at least 1500ma to run this thing right? (As I've said I have no clue what the hell I'm talking about so the second I say something wrong jump in...)
Also the PS needs to be regulated and filtered... I think... >_>
Tubes will probably be two 12au7 and one 12ax7... since from reading the forum the 12ax7 doesn't give as much volume boost but does seem to give a good gain boost... it placed at the end would allow for a really nice final push in gain that leads to full saturation and complete tube distortion... lastly avoid JJs as they don't seem to like the low volts...
I shall call it...
Ark's School of Rock
First Master = School of Clean Boost... :icon_smile:
Second Master = School of Over Drive... 8)
Third Master = School of Distortion... :icon_twisted:
For one can not rock... If one does not rock loud! (School's motto get used to it your stuck with it for four years.)
Final thoughts?
Quote from: rugeb on March 05, 2012, 12:13:45 PM
Quote from: runmikeyrun on March 04, 2012, 11:52:48 PM
Had a wicked hum in my valvy, didn't matter what PS I used or where in the house I was using it. I simply added a 7812 rectifier with (2) 220uF caps (one from the dc jack to ground, the other from power out to ground) and my valvy is SILENT. Dead silent. I just thought I'd throw that out there in case anyone else was having an issue.
Ok runmikeyrun: Tested! ;)
Now, the schematic:
(http://www.fuzzface.es/mods/HumReducer.jpg)
For 7812 voltage regulator VIN+ must be atleast 14.5V.
http://www.datasheetcatalog.org/datasheets/150/44435_DS.pdf
Quote from: thereminator on March 06, 2012, 09:14:17 AM
Quote from: rugeb on March 05, 2012, 12:13:45 PM
Quote from: runmikeyrun on March 04, 2012, 11:52:48 PM
Had a wicked hum in my valvy, didn't matter what PS I used or where in the house I was using it. I simply added a 7812 rectifier with (2) 220uF caps (one from the dc jack to ground, the other from power out to ground) and my valvy is SILENT. Dead silent. I just thought I'd throw that out there in case anyone else was having an issue.
Ok runmikeyrun: Tested! ;)
Now, the schematic:
(http://www.fuzzface.es/mods/HumReducer.jpg)
For 7812 viltage regulator VIN+ must be atleast 14.5V.
Ok!
I haven't problem: my power supply is with regulated voltage.
EDIT:
Schematic Power Supply with regulated voltage (1000mA):
(http://www.fuzzface.es/mods/PowerSupply1A.jpg)
Still reading through the posts here regarding hum reduction, and a couple other points...
Q1) If my Cioks is well regulated, I shouldn't need the hum reduction circuit? I guess the proof will be in the pudding - whether I hear hum or not. The next 2 questions are more important...
Q2) How important is the buffer on the end of the circuit as shown in some examples, EG: the Boobtube. Why would this be used?
Q3) Specifically regarding the sound, how important are the different voltages being supplied to heaters and the plates? Will it for example smooth the sound out, or simply provide more headroom overall?
Quote from: candletears7 on March 06, 2012, 05:15:33 PM
Still reading through the posts here regarding hum reduction, and a couple other points...
Q1) If my Cioks is well regulated, I shouldn't need the hum reduction circuit? I guess the proof will be in the pudding - whether I hear hum or not. The next 2 questions are more important...
Q2) How important is the buffer on the end of the circuit as shown in some examples, EG: the Boobtube. Why would this be used?
Q3) Specifically regarding the sound, how important are the different voltages being supplied to heaters and the plates? Will it for example smooth the sound out, or simply provide more headroom overall?
Hi-
I just built one that was close to "stock" so I'll try to answer your questions based on my experience:
Q1) I agree- See how it sounds first and go from there. I used a cheap wall wart with 12vdc out and it works great. I started off with a rectifier and LM317 variable voltage regulator running off of a 20vac wall wart, but after burning my hand on the heat sink, I decided I didn't want to put an oven inside of my enclosure.
Q2) Mine is fine without a buffer. Kinda' the same as Q1-See how it sounds first and modify based on your tastes.
Q3) The heater voltages are very important. Try to keep the voltage across pins 4-5 less than 12vdc. I'm using 12vdc on the anode, but others have said that they prefer a higher voltage. Again, you might want to start with 12 and see how you like it. You'll have 12 anyway for the heaters, so why not try 12 on the anode to start with?
A few mods I made:
1) I used a rotary switch to provide 4 different cap values on the input.
2) I used a trim pot for R2 and dialed in the amount of "cleaness" I wanted when the gain is all of the way down.
3) I added a switch to turn the tone control on and off.
4) I am currently experimenting with clipping diodes and capacitors on the output to modify the distortion.
Sounds like you've thought this through well. I wish you good luck!
Quote from: Jdansti on March 07, 2012, 03:29:52 AM
Q3) The heater voltages are very important. Try to keep the voltage across pins 4-5 less than 12vdc. I'm using 12vdc on the anode, but others have said that they prefer a higher voltage. Again, you might want to start with 12 and see how you like it. You'll have 12 anyway for the heaters, so why not try 12 on the anode to start with?
Voltage across 4-5 pins must be 12,6V (+/- 5%). Too high or too low heater voltage can damage cathode.
Schematic with last mods:
(http://www.fuzzface.es/mods/ValveOverdrive+Mods.jpg)
Quote from: rugeb on March 07, 2012, 08:16:10 AM
Schematic with last mods:
(http://www.fuzzface.es/mods/ValveOverdrive+Mods.jpg)
Looks nice Rugeb. I notice that you are using symmetrical clipping. Have you tried asymmetric? Also, I found that at least one pedal manufacturer uses a 51pf cap in parallel with the clipping diodes to soften the clipping. Just curious if you've tried either of those mods.
Quote from: Jdansti on March 07, 2012, 02:57:22 PM
Looks nice Rugeb. I notice that you are using symmetrical clipping. Have you tried asymmetric? Also, I found that at least one pedal manufacturer uses a 51pf cap in parallel with the clipping diodes to soften the clipping. Just curious if you've tried either of those mods.
==============================================
Yes, I've seen it, but I have not tried this, but it may be interesting ...
EDIT:
You can substitute the diodes 1N4148 with RED LEDS or germanium diodes 1N34A, this will change the sound...
Thanks for comment!
MOD INPUT CAP (2 VERSIONS):
(http://www.fuzzface.es/mods/ValveCaster_MIC2.jpg)
So guys... I'd like to run the one I'm going to make at high voltage...
from reading this thread I understand that the heaters need 12.6 volts...
So...
would it be better to get a 12 volt PS and then just voltage pump a few times the rest of the circuit.
or... get like a 15v of 16v PS regulate down for the heaters and then voltage double to something like 28 or 30?
Also what kinda watts do I need to worry about when looking for a good PS.
Sorry I know a lot of stuff in this thread covers what to do to get good power but watts were never covered and I'd like to cover my bases.
Quote from: Ark Angel HFB on March 09, 2012, 02:35:37 AM
So guys... I'd like to run the one I'm going to make at high voltage...
from reading this thread I understand that the heaters need 12.6 volts...
So...
would it be better to get a 12 volt PS and then just voltage pump a few times the rest of the circuit.
or... get like a 15v of 16v PS regulate down for the heaters and then voltage double to something like 28 or 30?
Also what kinda watts do I need to worry about when looking for a good PS.
Sorry I know a lot of stuff in this thread covers what to do to get good power but watts were never covered and I'd like to cover my bases.
my measurements of this design show it pulls with a 12au7 3ma, and a 12ax7 1 -2 ma. So I use a voltage multiplier to take 12v to 60v. The multiplier is simple 2 transistors as a oscillator with two more for current feed. a ladder of caps and diodes. all of this on perf fits between the stomp switch and the bottom the box. http://www.sm0vpo.com/power/vconv_01.htm
I finished my Valve Overdrive 9V with some mods (tone & clipping switchable) with a very nice sounding fuzz.
It sounds great !
(http://www.fuzzface.es/mods/OverdrivePlus3.jpg)
Quote from: rugeb on March 09, 2012, 12:20:17 PM
I finished my Valve Overdrive 9V with some mods (tone & clipping switchable) with a very nice sounding fuzz.
It sounds great !
(http://www.fuzzface.es/mods/OverdrivePlus3.jpg)
Any sound clips with the mods?
I just bread boarded the valvecaster! just tested thru a lil battery amp to test if its working and it is!
I used this layout from Ren! read thru lots of this thread if not all of it and went thru Rens layout gallery thanks for all the work from everyone I love this project!
this is what I used
http://www.aronnelson.com/gallery/main.php/v/Renegadrian/Valvecaster-no-tone+6x8+diff_+plate+voltage.gif.html
I'm powering this with a dan electro 18v 150ma psu into a 7812 regulator and just running pin 5 to the 12v and 18v to the B+ in
I have a few questions
The dano wallwart Im using tests on my fluke and my cheap ddm at 28.4 volts. Is 150ma enough ?
I was going to use this
http://www.aronnelson.com/gallery/main.php/v/Renegadrian/40106+voltage+multiplier.gif.html
And I have all the parts on hand now for this multiplier my calcs say ill get 189.144 out of it
Is this safe for the circuit/tube ? data sheets for the 12ax7 I was looking at say 180v max for heater-cathode voltage and I think its pin 8 and 4 which is cathode(8) and heater(4) are connected to the board with the 189v Im planning on putting into it . I just want to be sure before I do something bad...
Also for the voltage multiplier I have a mix of 100v and 63v 47n caps is this ok ? or should they be rated over the voltage Im getting out of it ie over 189v same goes for the caps I have in the valvecaster, they are rated at 100v as well.
I feel like this is a stupid question because I always go by the rule of higher V rating caps then what Im feeding into it. :icon_redface:
I haven't made anything at high voltage yet so I just wanted to ask some question first.
Big thanks to everyone in this thread!
Glad you like my layouts!!!
ok we start with some info here http://www.nj7p.org/Tube4.php?tube=12AU7
the tube eats 150 mA for the heaters and some more for the anodes...I guess you're a little under specs,but who knows...
I use a 1A WW so I'm outta trouble, but 150 mA...mmm...just try it man...
Sometimes if a circuit needs more amp. the voltage goes down a little, so it could work good just with some voltage sacrifice...
Also from the datasheet, the plates can hold up to 330 V so just go ahead! Just look at the schem and don't pay attention to cathodes (at least for what refers to voltage...) - voltage goes to the plates (anodes) of the ckt...
Don't worry and use the components you have...the 40106 voltage multiplier I built uses regular ceramic caps...but for what I read it wants nomore than18 V
Ok so I do have it built on breadboard and it works and sounds pretty good running off this dano WW. I measured it on the fluke and its putting out 28.7vdc and 770ma so that should be good! Even though the label says 18v and 150ma I geuss it lied heh. ::)
I have some other psu's laying around from old printers and stuff but their output is 30VAC and I wasn't sure about using them.
Most of my ceramic caps are pretty high in voltage rating like 500v on average. I don't have any 47nf ceramics on hand just metal film box caps that are rated at 100v and one at 63v i have exactly 7 extra for the voltage multiplier. I just find it weird since normally you don't want to put more voltage into somethings rating. don't want any caps exploding in my face!I look so pretty this mustachio is my money maker! I could try it I'm just weary.
do you know off hand what your caps where rated ? If not don't worry to look, ill place a new order soon and get caps rated high.
I just got an old admiral 12au7 I have a 12bh7 coming in the mail now and I have a handfull of old mixed Ge and RCA 12ax7s from long long ago ! cant wait to test them all out ill post pics when its all done!
Thanks again for all the help and layouts ! :icon_biggrin:
Quote from: Mustachio on March 09, 2012, 08:26:06 PM
Ok so I do have it built on breadboard and it works and sounds pretty good running off this dano WW. I measured it on the fluke and its putting out 28.7vdc and 770ma so that should be good! Even though the label says 18v and 150ma I geuss it lied heh. ::)
I have some other psu's laying around from old printers and stuff but their output is 30VAC and I wasn't sure about using them.
If you have AC, you can put 12V AC on heaters and have a c0ckroft walton multiplier (diodes and caps)
Quote
Most of my ceramic caps are pretty high in voltage rating like 500v on average. I don't have any 47nf ceramics on hand just metal film box caps that are rated at 100v and one at 63v i have exactly 7 extra for the voltage multiplier.
do you know off hand what your caps where rated ? If not don't worry to look, ill place a new order soon and get caps rated high.
My ceramics haven't got the voltage written, only 473...Guess they're 63 or 100.
I suggest you to keep an eye at the voltage at the multiplier - google for the datasheet to see its maximum V in!
Quote
I just find it weird since normally you don't want to put more voltage into somethings rating. don't want any caps exploding in my face!I look so pretty this mustachio is my money maker! I could try it I'm just weary.
Now that made me laugh hard! :icon_biggrin:
Quote
I just got an old admiral 12au7 I have a 12bh7 coming in the mail now and I have a handfull of old mixed Ge and RCA 12ax7s from long long ago ! cant wait to test them all out ill post pics when its all done!
bh7 are good!
Quote
Thanks again for all the help and layouts ! :icon_biggrin:
Glad if I can help somehow!
Ah CD40106BE max voltage in 15v ... I do have a few other if-y wall warts, one old radio shack psu that has multiple voltage selector switch. But when I was testing it on the ddm it was giving me 17-18volts no mater what position the switch was in. Ill test a few more I have laying around the house and I think ill give this multiplier a try with the 100v 47nf caps I got. Ill just wear a stache gaurd! :{D I need a mustache smiley icon!
Running it with the 28 volt danelectro wallwart into the 7812 for pin 5 and the rest going to the B+ it sounded pretty good ! thanks again for all the fast response Ren you are great! Gonna move the main circuit off the bread board and onto some vero tomorrow!
Now looking at the CD40106BE with 15 max in 15x6.66 is about 100volts so most of my caps should hold up! If I can find a strong 12v psu around the house ill get almost 80v out of it . Ill check out that c0ckroft walton multiplier tonight as well ! maybe ill be able to power tubes at higher voltage. I eventually want to build a few projects with EM84 magic eye tubes!
Quote from: rugeb on March 09, 2012, 12:20:17 PM
I finished my Valve Overdrive 9V with some mods (tone & clipping switchable) with a very nice sounding fuzz.
It sounds great !
(http://www.fuzzface.es/mods/OverdrivePlus3.jpg)
Nice looking build!
Rene,
i'm a bit confused about your layout..
what i have is the one with c3 NP cap and in the gallery you put a layout with c3 as polarized cap.
i didnt made the layout yet cause i'm waiting for some parts to arrive.
can you please advise me?
Q ..
i'm a bit confused about the wall wart that i'll be using, i see all kind of wall warts in this post.
my plan is to use an regulated 12V wall wart, as i understand it will work fine with it, but i see on page 144 that Mustachio talked about multiply the V, for what reason if i may ask?
will it be a better results with more V?
Q ..
in here http://www.aronnelson.com/gallery/main.php/v/Renegadrian/Valvecaster-no-tone+6x8+diff_+plate+voltage.gif.html
there is B+V inserts?
i dont understand...
you wrote..
"12V goes only to pin 5 - B is whatever voltage you want to apply to the plates."
what is B?
as i understand B can be any V i want to use?
to what pin B is connected?
do i take B from the same wall wart?
sorry for the lots of questions, i'm trying to understand and to learn.
thank you very much,
Sincerely,
Isak E.
Quote from: Isak on March 10, 2012, 10:37:28 AM
Rene,
i'm a bit confused about your layout..
what i have is the one with c3 NP cap and in the gallery you put a layout with c3 as polarized cap.
i didnt made the layout yet cause i'm waiting for some parts to arrive.
can you please advise me?
Q ..
i'm a bit confused about the wall wart that i'll be using, i see all kind of wall warts in this post.
my plan is to use an regulated 12V wall wart, as i understand it will work fine with it, but i see on page 144 that Mustachio talked about multiply the V, for what reason if i may ask?
will it be a better results with more V?
Q ..
in here http://www.aronnelson.com/gallery/main.php/v/Renegadrian/Valvecaster-no-tone+6x8+diff_+plate+voltage.gif.html
there is B+V inserts?
i dont understand...
you wrote..
"12V goes only to pin 5 - B is whatever voltage you want to apply to the plates."
what is B?
as i understand B can be any V i want to use?
to what pin B is connected?
do i take B from the same wall wart?
sorry for the lots of questions, i'm trying to understand and to learn.
thank you very much,
Sincerely,
Isak E.
Isak:
If you want to simplify your build, use this schematic and values. Disregard my drawing regarding the voltage regulator on the DC jack.
(http://i622.photobucket.com/albums/tt308/reaperQ45/Valvecaster/Valvecasterwith7812voltageregulator.jpg)
The resistor value to the LED is 4.7K. C3 is a electrolytic cap with positive going to Pin 6.
Make your 12v wall wart is putting out 12v at the plug and that the plug orientation is pin (negative), sleeve (positive).
B is the supply voltage. You do not want to exceed 12.6V to the heaters; otherwise, you run the risk of burning them out or shortening their service life.
The values I have listed on the schematic I derived from reading all 145 pages and found that they were the best for me and to use with a single coil or humbucker guitar.
I did put a ON-ON switch at C1 and used two different NP caps for a lighter/darker sound depending on the guitar.
Hope this helps and good luck.
@Isak: the 'B' referred to is the voltage applied to the plates. In the standard build, the 12 volt supply is used both for the heater and the plate voltage. With a voltage multiplier, the 12 volts goes to the heater only, and the multiplied (higher) voltage goes to the plates. Larry
@ Isak E.
C3 can be either NP or polarized...I tend to use the latter as its smaller size...
You can go straight with 12 V serving the whole ckt - adding more V to the plates will give you more "air", dynamics, headroom or whatever way you wanna call it!!! XD
If you want to use a voltage multiplier, be sure to provide 12V to the heaters and the increased voltages to the plates, which are pins 1 and 6. Voltage is meant to be any kind you want, basically the tube can get up to 330 V but without going that high and using a trafo you can use a simple multiplier to get from 48 V to 200 V.
thank you for the info.
i'v never worked with Tubes so still learning here :)
thanks again,
Isak E.
Hi Patrick,
Just wondering - what's the Switch (0.056uF Cap, 22k resistor) coming from Pin 8 going to the output tip do?
I feel a little dizzy but after an hour of thinking this over here is what I'm at.
As far as powering this thing is concerned I can ether go with a 12vDC then boost that... http://www.mpja.com/12VDC-1A-Plug-Supply-55_21mm-Plug/productinfo/19087+PS/
just go with a 15vDC regulate down for heaters... and boost the 15vDC for more head room... http://www.mpja.com/15V-16A-DELTA-PLUG-POWER-SUPPLY/productinfo/16714+PS/
the advantage of the 15vDC is that by regulating down the power is well... regulated meaning the power will be both regulated and filtered.
so...
Q1: Are the two wall warts I linked two seem good to you more experiences dudes?
Q2: Which one, if it was your money, would you personally go with?
None actually...
Switching power supplies are not the best thing to use with pedals....
I am powering my valvecaster with 9volt and it sounds cool!
High output and a lot of grit.
1. may C3 be non pole capacitor like 1mf wima red block?
2 .how does it handle on 12V ?
3. is it good for preamp ?
Quote from: DUCKFACE on March 11, 2012, 05:07:29 PM
1. may C3 be non pole capacitor like 1mf wima red block?
Yes, As I wrote it can be NP or electro...while I prefer electro (for its smaller dimentions) a NP cap can be used. WIMAs are a good choice!
Quote
2 .how does it handle on 12V ?
3. is it good for preamp ?
You mean the whole ckt?! IT IS a preamp/booster, intended to work at 12V. The very first incarnation of it (by the great Dano) works quite great, altough it is a nice base for experiments and variations.
Quote from: tasos on March 11, 2012, 07:48:37 AM
None actually...
Switching power supplies are not the best thing to use with pedals....
I am powering my valvecaster with 9volt and it sounds cool!
High output and a lot of grit.
Forgive my lack of knowledge but why is switching power supply bad?
Also how about everyone give a modle number of the PS we are using... it might be a good thing to add as let face it none of us are made of money and find the right adaptor for the right price is a good thing. ^_^
A SMPS is not bad on its own, its when you have a SMPS plug and a SMPS inside of the pedal you can have issues of hydrodyning (http://en.wikipedia.org/wiki/Heterodyne), but with a stock valve caster I see no issues at all, as long as they have a high enough switching frequency.
I have a 12v wall wart from Radio Shack, which I believe is a SMPS and a Voltage multiplier (which is a SMPS) in my valvecaster giving me 70v on the plates. This works well and I have zero issues. Others have done the same with no issues. If you start @ 9v with a onespot I have found also no issues. Using ricks SMPS design giving me 120v on the plates, and using a voltage regulator to get 6.3v on the heaters.
Wanting to try to build a pcb version. Does anyone know if the socket sold on smallbear is a pcb socket? It doesn't say on the page and I tried e-mailing them a while back and got no response.
Quote from: bassmannate on March 17, 2012, 09:13:46 PM
Wanting to try to build a pcb version. Does anyone know if the socket sold on smallbear is a pcb socket? It doesn't say on the page and I tried e-mailing them a while back and got no response.
Just look at the lugs on the bottom of the socket... if they look like they'd be a bitch to solder... they are PBC. XD
at least that is my rule of thumb. ^_^
Here is mine, not so pleased with the metal work...
(http://imageshack.us/photo/my-images/33/img3457lx.jpg)
(http://imageshack.us/photo/my-images/717/img3458ee.jpg)
Thank you all and especialy Adriano :)
Quote from: chris73 on March 18, 2012, 07:20:58 AM
Here is mine, not so pleased with the metal work...
http://imageshack.us/photo/my-images/717/img3458ee.jpg (http://imageshack.us/photo/my-images/717/img3458ee.jpg)
http://imageshack.us/photo/my-images/33/img3457lx.jpg (http://imageshack.us/photo/my-images/33/img3457lx.jpg)
Thank you all and especialy Adriano :)
(links fixed)
Nice! Glad if I helped you somehow!!!
Quote from: Ark Angel HFB on March 17, 2012, 10:50:42 PM
Quote from: bassmannate on March 17, 2012, 09:13:46 PM
Wanting to try to build a pcb version. Does anyone know if the socket sold on smallbear is a pcb socket? It doesn't say on the page and I tried e-mailing them a while back and got no response.
Just look at the lugs on the bottom of the socket... if they look like they'd be a bitch to solder... they are PBC. XD
at least that is my rule of thumb. ^_^
I'm well aware of what PCB lugs look like. Unfortunately, the item description on Small Bear doesn't say and the picture is of the top of the socket. You can't see the lugs. Is there anyone who's bought tube sockets from Small Bear before that can comment?
Well I moved it off the bread board and onto some vero I made black. I added a 7812 to the right side of the board added a single 100uf cap on the power side coming in nothing on the going out.
I have hum but here's what my thoughts are maybe you can confirm or deny. the power coming in is from a danelectro zero hum wall adapter that's rated at 18vdc 150ma. It reads out 28.6vdc and 748ma so I figured it would have enough juice to push this circuit. I ran a jumper right in front of the power coming from the wall wart to the B+ so its unregulated I'm guessing , then it hits the 100uf cap on the + and into the regulator the - of the cap goes to center ground on the regulator and the right side is the 12v regulated out.
I'm guessing I'm getting hum from the unregulated power coming into the B+ straight from the wallwart. If I move the B+ jumper(blue wire on left side of regulator) behind the 100uf cap will that help ? or should I send the wallwart power to a 7818 before it hits B+ . that way power coming into it goes left to a 7818 making 18v regulated for B+ and goes on to the 7812 for pin 5.
Also I'm planning on making the voltage multiplier to feed B+ later and Id like your advice . The IC is rated at max 18v in , so should I go with my 18v regulator or a 15v regulator the 7815 and feed the chip 15v to be on the safe side ? And am I getting into danger areas on heat if i used 2 regulators and a multiplier in the same box?
I hope this makes sense my mustachio curled up just typing about it haha. :icon_mrgreen:
In the pics I have a 12BH7 in there Haven't had a chance to test it with the 12au7 or 12ax7s I have. I did test it with a 12v 1amp walwart same hum then it mysteriously stopped working after 30 seconds and I plugged back in the danelectro wart Ive been using from the start and it worked again ???
I built the tube cage with parts from the hardware store under 5 bucks and left over parts still to make a few more. Might go with different material next time or sand and polish these up. Or even paint! Got to use my new drill press on this box! was a lot of fun! and I hand sanded the top with some 1000 and then 2500 grit paper. Still has a lil more work to go. Used a bud industries CU-471 box . Pretty nice size.
(https://lh3.googleusercontent.com/-Ht_85L9fyJE/T2ZgVPH_MAI/AAAAAAAAArg/PneP2jqfoYM/s1303/IMAG1511.jpg)
Guts
(https://lh4.googleusercontent.com/-DQFFwxdf-Pg/T2ZgbCUZbII/AAAAAAAAAro/21u4aH5qa5U/s815/IMAG1507.jpg)
(https://lh4.googleusercontent.com/-5YFh2abSxwQ/T2Zgn2H5JaI/AAAAAAAAArw/CeOnj-O9fcU/s815/IMAG1488.jpg)
[EDIT]
Opps I used this layout but moved the regulator down to unused space on my vero
http://www.aronnelson.com/gallery/main.php/v/Renegadrian/Valvecaster-no-tone+6x8+diff_+plate+voltage.gif.html
and this is the multiplier Im planing on making just shy one cap at the moment.
http://www.aronnelson.com/gallery/main.php/v/Renegadrian/40106+voltage+multiplier.gif.html
Could someone please take a look at my calculations below and let me know if I'm on track?
I've built a Valvecaster using a 12AU7 at 12v and it works fine. I would like to substitute some 6N6P and 6N1P-EB tubes I have to see how they sound, but the heater voltage rating for these tubes is 6.3v across pins 4 & 5, and pin 9 is not connected between the heaters as it is on the 12A?7 tubes. Otherwise, the pin out is the same.
Based on calculations I found at http://www.diyforums.org/MAX/MAXheaterResistor.php, I think that I can place a 10 ohm resistor in series with the heater to drop the voltage close to 6v.
The procedure:
1) calculate the normal heater power based on the specs,
2) calculate the heater resistance,
3) assume a 12v PS and a 10 ohm (a guess) resistor in series with the heater to calculate the resulting current,
4) calculate the voltage drop and the voltage that the heater would see.
Any comments would be appreciated.
Heater Rating: 6.3v, 750mA
Heater Power
P = V x I
P = 6.3 x 0.750
P = 4.725W
Heater Resistance
R = P/I^2
R = 4.725 / 0.750^2
R = 8.4 ohms
Assume: 12.6V PS and R1 = 10ohm resistor in series with heater.
Current
I = V/(Heater R + R1)
I = 12.6/(8.4+10)
I = 685mA
Voltage Drop Across R1 (10 ohms)
V = I x R
V = 0.685 x 10
V = 6.85v
Heater Voltage
V = PSv-Vdrop
V = 12.6 - 6.85
V = 5.8v
I would need to make sure that the resistor was either rated at 1W, or use two 20 ohm 1/2W resistors in parallel. My power supply is rated at 1200mA, so it should be fine. Thanks in advance.
Correction- it looks like a voltage drop of 6 volts across a 10 ohm resistor would be around 4W, meaning I should use a 5W resistor. Any thoughts on this?
If your PS is unregulated, it would hard guarantee that the heater would be getting a specific voltage. You might do better with an LM317 - it only needs a few extra parts.
Quote from: waltk on March 21, 2012, 09:10:38 AM
If your PS is unregulated, it would hard guarantee that the heater would be getting a specific voltage. You might do better with an LM317 - it only needs a few extra parts.
Thanks Walt. The PS is an off brand that doesn't say whether it is regulated or not. It delivers 12vdc on my Valvecaster, but if I bump the load up to 750ma from 300ma, the voltage could dip if it is unregulated. The best thIng would be to use the LM317 as you suggest and not worry about wall wart being regulated. Come to think of it, if I use the LM317 for the heater, I could use an 18vdc PS I have and get more headroom on the plates. Thanks again.
QuoteThanks Walt. The PS is an off brand that doesn't say whether it is regulated or not. It delivers 12vdc on my Valvecaster, but if I bump the load up to 750ma from 300ma, the voltage could dip if it is unregulated. The best thIng would be to use the LM317 as you suggest and not worry about wall wart being regulated. Come to think of it, if I use the LM317 for the heater, I could use an 18vdc PS I have and get more headroom on the plates. Thanks again.
Sounds like a good plan. One thing to keep in mind; the LM317 will have to dissipate (the voltage differential X the current) as heat - (18 - 6.3) * 750ma = 8.78 watts. You'll probably want a decent heat sink on it.
Quote from: waltk on March 21, 2012, 06:50:34 PM
QuoteThanks Walt. The PS is an off brand that doesn't say whether it is regulated or not. It delivers 12vdc on my Valvecaster, but if I bump the load up to 750ma from 300ma, the voltage could dip if it is unregulated. The best thIng would be to use the LM317 as you suggest and not worry about wall wart being regulated. Come to think of it, if I use the LM317 for the heater, I could use an 18vdc PS I have and get more headroom on the plates. Thanks again.
Sounds like a good plan. One thing to keep in mind; the LM317 will have to dissipate (the voltage differential X the current) as heat - (18 - 6.3) * 750ma = 8.78 watts. You'll probably want a decent heat sink on it.
Right. I've used the LM317 with one of those fin type heat sinks before and it was hot enough to burn me. I might try a larger chunk of metal and possibly put it in it's own ventilated box external to the stomp box. I guess there really is "no free lunch". Thanks!
QuoteRight. I've used the LM317 with one of those fin type heat sinks before and it was hot enough to burn me. I might try a larger chunk of metal and possibly put it in it's own ventilated box external to the stomp box.
You might be able to use the stompbox enclosure itself as a large heatsink. The "Tiny Giant" amp does this for both the chipamp and the voltage regulator, and it works great. The only thing to be careful about is that the TO220 tab on the LM317 is internally connected to its OUTPUT (not ground). So you have to mount it such that the tab is electrically isolated from the enclosure - but thermally connected to it. The Tiny Giant uses a thin insulator for this.
PS multi voltage
(http://www.fuzzface.es/mods/PS-multivoltage.jpg)
Quote from: waltk on March 22, 2012, 07:15:12 AM
QuoteRight. I've used the LM317 with one of those fin type heat sinks before and it was hot enough to burn me. I might try a larger chunk of metal and possibly put it in it's own ventilated box external to the stomp box.
You might be able to use the stompbox enclosure itself as a large heatsink. The "Tiny Giant" amp does this for both the chipamp and the voltage regulator, and it works great. The only thing to be careful about is that the TO220 tab on the LM317 is internally connected to its OUTPUT (not ground). So you have to mount it such that the tab is electrically isolated from the enclosure - but thermally connected to it. The Tiny Giant uses a thin insulator for this.
Thanks - that's a good idea. I haven't been brave enough yet to try using the insulator that comes with the regulators. I usually modify my projects, if necessary, to have a negative ring on the DC jack and make the case the ground. It would be nice if they designed the regulators with the ground on the tab so that they could just be bolted directly to the case for the most efficient heat dissipation. It's probably time to give the insulator a try.
Quote from: rugeb on March 22, 2012, 07:24:36 AM
PS multi voltage
(http://www.fuzzface.es/mods/PS-multivoltage.jpg)
Thanks Rugeb. I've been thinking about doing something like this for a pedal board PS with multiple voltages. I'm curious to know if there is an advantage to connecting the regulators in series as shown in your schematic as opposed to parallel.
QuoteThanks Rugeb. I've been thinking about doing something like this for a pedal board PS with multiple voltages. I'm curious to know if there is an advantage to connecting the regulators in series as shown in your schematic as opposed to parallel.
Excuse for for butting in, but I think I can answer that. One advantage would be that the 7809 and 7805 have a smaller voltage drop, and therefor have to dissipate less power (as heat) than they would from the original 18v. Don't know for sure, but they might also be less likely to have any ripple on their output (because their input is already regulated).
Quote from: waltk on March 22, 2012, 12:18:39 PM
QuoteThanks Rugeb. I've been thinking about doing something like this for a pedal board PS with multiple voltages. I'm curious to know if there is an advantage to connecting the regulators in series as shown in your schematic as opposed to parallel.
Excuse for for butting in, but I think I can answer that. One advantage would be that the 7809 and 7805 have a smaller voltage drop, and therefor have to dissipate less power (as heat) than they would from the original 18v. Don't know for sure, but they might also be less likely to have any ripple on their output (because their input is already regulated).
Ok Waltk!
With a serial connection, the 7809 and 7805 have a smaller voltage drop. The paralell connection increases the voltage drop in the 7809 stage, and much more in the 7805 and has to dissipate more heat.
I ended up putting an 7815 in mine before it went to B+. to regulate my 18v coming into it. minimum of the 7815 is 17v so I wanted to play it safe. It took out the hum when using a 12au7. Popped in the 12bh7 last night with same set up and hum came back ??? Im only using a single 100uf at the first regulator a 7812.
So I have a lil more experimenting to do. What I've noticed with mine so far is it has lots of volume (unity around 10 O'clock) and the only gain settings I like are when its all the way maxed, and I'm not a high gain player. It sounds pretty nice tho going into a clean bassman amp for blues, but still need to tweak it a bit.
Gonna play with resistor values for more gain. Also I noticed when I back off the gain is when I get more hum. I might try putting more caps across the regulators.
I wanna say thanks to all nerds in this thread! :icon_mrgreen: This is my favorite thread of all time! You guys are great for all the knowledge you pass along. Ive learned sooo much in a short time from you guys. This is what the internet is all about! :'( shucks guys ya done got me going
PS multi-voltage mod:
A solution for heater: Add two 1N4007 standard diode it will give you 6,4V (1,4V extra).
They are increasing in steps of 0,7V.
Output voltage= 5 + 0,7 + 0,7 = 6,4
It's cool!
(http://www.fuzzface.es/mods/PS-multivoltage2.jpg)
I am in the middle of a valvy and I just wanted to report some observations on tube brands and voltage readings, specifically on the plates (pins 1 and 6) at idle. I am using stock 220k and 100k plate resistors, and 12VDC regulator.
-With a new production JJ 12au7 I am getting 10v on pin 1 and 9.6v on pin 6. The sound is fizzy, dull, and thin, and output is near unity at max.
-I swap in either of two early 60's RCA black plate 12au7s and voltages drop to 3.6v on both pins 1 and 6. Tone is full, rich, and fuzzy and output is much much higher.
No matter what I did to try to reduce the voltage to the plates with the JJ tube, the tone just got worse and worse. Which is weird, because the JJ 12au7s i've used in the past in valvecasters sound really really good.
The reason I posted this is because there are quite a few people who have issues with their valvy and plate voltages usually seem way off compared to Rick's. So when you're checking voltages and things look amiss, try a different brand of 12au7 after you've given your soldering job the once over. It might be all you need to do.
Now for a question- I am getting a good amount of sag when I hit the strings even moderately hard. I can't figure out why. I am using the standard valvy schematic except for a 1M pot in between pins 1 and 7 (gain pot) and both cathodes are grounded, no resistors. I'm using a 16v supply regulated to 12v via 7812. Upon audioprobing, signal into pin 2 is just fine, but coming out of pin 1 I already have the sag. I checked the current to pin 1 and it's 73ua at idle, and drops to ~35ua when hitting the strings. That's MICRO amps, not milliamps. This seems low, because I checked the RCA datasheet for my tube (an early 60s 12au7a) and it says I should have 2-3ma of plate current @ 12v.
I've got a 220uF cap to ground from each the input voltage and regulated voltage. I'm using a 1A supply and my regulator is rated for 1A. I've tried different tubes, a different power supply, different cables, going into the amp's effect return, still no change. My guitar is passive. I am getting no voltage sag on the supply or regulated voltages when I play. Could it be the gain stages are misbiased? I really can't figure this out. Help!!
EDIT: Nevermind, I got it. As soon as I put some sort of resistor on pin 3 the sag went away. Guess it was misbiased!
BTW... there's guys selling NOS RCA 12au7a tubes out there on eBay for CHEAP... I got two that were labelled Conn (organs) for $8 plus $2.50 shipping. They sound incredible! You can tell NOS RCA because they had an octagon around the tube number etched in the tube.
Quote from: rugeb on March 22, 2012, 02:33:59 PM
Quote from: waltk on March 22, 2012, 12:18:39 PM
QuoteThanks Rugeb. I've been thinking about doing something like this for a pedal board PS with multiple voltages. I'm curious to know if there is an advantage to connecting the regulators in series as shown in your schematic as opposed to parallel.
Excuse for for butting in, but I think I can answer that. One advantage would be that the 7809 and 7805 have a smaller voltage drop, and therefor have to dissipate less power (as heat) than they would from the original 18v. Don't know for sure, but they might also be less likely to have any ripple on their output (because their input is already regulated).
Ok Waltk!
With a serial connection, the 7809 and 7805 have a smaller voltage drop. The paralell connection increases the voltage drop in the 7809 stage, and much more in the 7805 and has to dissipate more heat.
Thanks Walt and Rugeb. It seems that the series arrangement would cause the individual regulators to be cooler, but the total heat dissipation would be the same-just guessing based on my limited understanding of the laws of thermodynamics. On the other hand, there's a lot I don't know about regulators, so maybe everything would be happier in series.
In Rugeb's schematic each regulator could be connected to a load as well as the next regulator in series, so you would have to avoid exceeding the current limits of the upstream regulators.
runmikeyrun: Do not change the 12AU7 yet. Try with another PS, may be a problem of PS.
Jdansti: Yes, you would have to avoid exceeding the current limits of the upstream regulators.
For more current in first stage:
(http://www.fuzzface.es/mods/7812+TIP42.jpg)
Rugeb,
see my edit to my post. I got it, thanks!
Quote from: runmikeyrun on March 22, 2012, 08:05:25 PM
Rugeb,
see my edit to my post. I got it, thanks!
Ok. Congratulations!
Post it with an image (for everybody with the same problem).
Quote from: Mustachio on March 22, 2012, 04:55:26 PM
I ended up putting an 7815 in mine before it went to B+. to regulate my 18v coming into it. minimum of the 7815 is 17v so I wanted to play it safe. It took out the hum when using a 12au7. Popped in the 12bh7 last night with same set up and hum came back ??? Im only using a single 100uf at the first regulator a 7812.
So I have a lil more experimenting to do. What I've noticed with mine so far is it has lots of volume (unity around 10 O'clock) and the only gain settings I like are when its all the way maxed, and I'm not a high gain player. It sounds pretty nice tho going into a clean bassman amp for blues, but still need to tweak it a bit.
Gonna play with resistor values for more gain. Also I noticed when I back off the gain is when I get more hum. I might try putting more caps across the regulators.
I wanna say thanks to all nerds in this thread! :icon_mrgreen: This is my favorite thread of all time! You guys are great for all the knowledge you pass along. Ive learned sooo much in a short time from you guys. This is what the internet is all about! :'( shucks guys ya done got me going
I use a 7812, and I have a 220uF 35v cap on each "side" of the regulator. A higher value such as 330 or 470uF would be ok too, but probably overkill and will start increasing dramatically in size. One cap goes from Vin pin to ground, and the second goes from Vout to ground. Be sure to observe correct polarity with the caps. I place the caps about 1-2 cm away from the regulator because I'm afraid the heat might break down the caps and/or reduce the voltage rating of the dielectric- you can either leave the leads long and exposed or solder in jumpers if you have them.
Good luck.
So after three failed attempts I finally build one of these... what a sound... I just build the standard one on teh first page and ran it on a battery after my wall wart gave to much hiss/buzz... going to get a voltage redulator as well as some other stuff to mod it out later.
for now I can honestly say it is the best OD/Gain circuit I've ever played... at least it does everything that I want.
The sound isn't compressed really... and it responds so great to pick attack. I can go from just the slightest of OD to full blow Hard rock distortion just by playing harder... I don't even have to touch my volume knob to clean up, lol I can just play softer. For a player who plays with a lot of feeling... it is a very special thing.
Sadly there are two problems I need help with.
1. I'm happy with this pedal at 12vDC... and have ordered a wall wart for it... my wallwart is 12vDC but possibly unregulated/filtered. Can I put a 7812 and filter after it to allow for steady clean DC. what I'm asking is if a 7812(http://www.mouser.com/ProductDetail/Fairchild-Semiconductor/KA7812ETU/?qs=ggemxziv1LLpCwqgzLaoT6NdYARBj95Hoguf%252bhBn4N0%3d) can be used with a wall wart that is already supposed to give 12 volts.
2. This is a weird one and I guessing I've @#$%ed the grounding some how... The signal gets louder when I place my hand on anything grounded inside the circuit or on my guitar. When I'm not touching something the volume drop dramatically and the sound gets flabby and bad. I've tried this with three different guitars so at this point I'm pretty sure something fishy is up with my wiring.
Should is it ok to ground everything to the input jack sleeve... or should I have just grounded it back to teh DC jack... or the out put sleeve... do some things need to be grounded to separate grounds???
please help when you can. ^_^
Quote from: Ark Angel HFB on March 31, 2012, 11:53:55 PM
So after three failed attempts I finally build one of these... what a sound... I just build the standard one on teh first page and ran it on a battery after my wall wart gave to much hiss/buzz... going to get a voltage redulator as well as some other stuff to mod it out later.
for now I can honestly say it is the best OD/Gain circuit I've ever played... at least it does everything that I want.
The sound isn't compressed really... and it responds so great to pick attack. I can go from just the slightest of OD to full blow Hard rock distortion just by playing harder... I don't even have to touch my volume knob to clean up, lol I can just play softer. For a player who plays with a lot of feeling... it is a very special thing.
Sadly there are two problems I need help with.
1. I'm happy with this pedal at 12vDC... and have ordered a wall wart for it... my wallwart is 12vDC but possibly unregulated/filtered. Can I put a 7812 and filter after it to allow for steady clean DC. what I'm asking is if a 7812(http://www.mouser.com/ProductDetail/Fairchild-Semiconductor/KA7812ETU/?qs=ggemxziv1LLpCwqgzLaoT6NdYARBj95Hoguf%252bhBn4N0%3d) can be used with a wall wart that is already supposed to give 12 volts.
2. This is a weird one and I guessing I've @#$%ed the grounding some how... The signal gets louder when I place my hand on anything grounded inside the circuit or on my guitar. When I'm not touching something the volume drop dramatically and the sound gets flabby and bad. I've tried this with three different guitars so at this point I'm pretty sure something fishy is up with my wiring.
Should is it ok to ground everything to the input jack sleeve... or should I have just grounded it back to teh DC jack... or the out put sleeve... do some things need to be grounded to separate grounds???
please help when you can. ^_^
Sounds like the circuit is reacting to the capacitance of your body. Have you installed the circuit inside of a metal enclosure yet?
You say that you are running it off of a battery. I assume 9v. If so, you're going to drain it pretty quickly due to the current draw of the heaters. I wonder if it might be behaving funny due to the voltage being too low. You might want to check your battery's voltage with the unit on.
Back to the the volume behavior, if it is still unboxed, I would want to see how it behaves after it is installed in the enclosure and you have 9-12v.
Regarding the regulator, my understanding is that they need 3v input above the rated voltage. You might want to check the spec sheet.
Regarding grounding, some people live and die by "star" grounding to theoretically avoid ground loops. I've also read that any ground loops inside of a stomp box should be small enough to not cause any problems.
I know I didn't have definitive answers, but hopefully this helps.
Quote from: Jdansti on April 01, 2012, 12:37:16 AM
Sounds like the circuit is reacting to the capacitance of your body. Have you installed the circuit inside of a metal enclosure yet?
You say that you are running it off of a battery. I assume 9v. If so, you're going to drain it pretty quickly due to the current draw of the heaters. I wonder if it might be behaving funny due to the voltage being too low. You might want to check your battery's voltage with the unit on.
Back to the the volume behavior, if it is still unboxed, I would want to see how it behaves after it is installed in the enclosure and you have 9-12v.
Regarding the regulator, my understanding is that they need 3v input above the rated voltage. You might want to check the spec sheet.
Regarding grounding, some people live and die by "star" grounding to theoretically avoid ground loops. I've also read that any ground loops inside of a stomp box should be small enough to not cause any problems.
I know I didn't have definitive answers, but hopefully this helps.
I don't have it in a box yet... but that still doesn't explain how me touching guitar strings or the guitar's bridge would make the volume of the pedal jump up... could you explain the capacitance reaction you are talking about. I ask because the sound when I'm touching the metal is the sound I want all the time... which leaves me with two options... Find out what the hell is going on... or attach a lead to my wrist and tie it to my guitar bridge... Help me out so I don't have to do option 2. XD
thanks for the regulator tip... I might order some 9AU7 tubes and use my coming, and probably now useless 12vDC with a 9 volt regulator to get ride of the hum...
As for the power supply, i found an old Sagem phone charger with very well regulated 12VDC 1.5A! Works realy great and so, my suggestion is to dig around in our junk boxes, we may find treasures :)
Ok fix'ed my problem... it wasn't a grounding loop... but rather a lack of grounding at all... kinda...
See I know all about grounding loops... and wanted to avoid one... so I ground everything into a single wire, then grounded that into my input Jack sleeve... which is great... except I didn't ground my input jack sleeve over to my output sleeve mean I had a ground break in my circuit...
problem fixed... no weird noise jumps... now i simply await some more passive components so that I can try a few filter set ups for my Power Supply and which over to the value-master version and see if I like it better.
Will keep everyone up to date... ^_^
Quote from: Ark Angel HFB on April 01, 2012, 04:07:32 PM
Ok fix'ed my problem... it wasn't a grounding loop... but rather a lack of grounding at all... kinda...
See I know all about grounding loops... and wanted to avoid one... so I ground everything into a single wire, then grounded that into my input Jack sleeve... which is great... except I didn't ground my input jack sleeve over to my output sleeve mean I had a ground break in my circuit...
problem fixed... no weird noise jumps... now i simply await some more passive components so that I can try a few filter set ups for my Power Supply and which over to the value-master version and see if I like it better.
Will keep everyone up to date... ^_^
Great! Glad you got it figured out! Have fun with it!
just some more observation for those interested in talking things over... or helping... which ever.
1. The difference between 9vDC and 12vDC is massive in two ways. One the output is so much louder, and two it develops a completely horrible fatty bass. so very weird that the 9vDC doesn't do this all that much...
2. From what I can tell this pedal is a very odd little thing... and massively voltage sensitive as far as what the end EQ will sound like. for sure to much bass is present with the stock one... later tonight or tomorrow I will be setting up a test board. (This a pro mans bread board just with card board and jumper cables. XD)
3. I found a cheap power supply that give out a wonderful regulated 12vDC and is filtered as well... in the end the pedal is silent with it so I'm super happy.
If you're running 9 volts, try a 9AU7 tube, and see what you think.
Hi,
I wonder if anyone can help me. I know a few folks have built high voltage valvecasters using charge pumps or SMPS's, and having built a few of stock valvecasters, I want to play with higher voltage (~60v) as I've read the sound improves.
My question is about the output signal. Do you need some kind of buffer between a high voltage valvecaster and the next stage in your signal chain (amp/pedal)? Is that necessary?
When running the plate at high voltage, is the output therefore at high voltage? As far as I understand it, the P-P swing can be in the 10's of volts, depending on your HT.
I see from studying schems such as the firefly that the caps between pre and power amp are 400v. I wondered if it is possible to use a high voltage valvecaster (by high, I mean ~60v) as the pre-amp for a 12k5 power stage, which runs at 12V on the plate. Can I mix and match the plate voltages like this? The 12k5 datasheet says the max voltage going into g2 is around 20v so I don't want to melt any tubes!
Sorry if this question makes no sense, or I have misunderstood something fundamental about how tubes and pre-amps operate, I have been reading up on the theory as best I can, but it's a lot to take in, especially when you're teaching yourself.
Cheers,
Chris
your on the right track. Yes higher voltage valvecasters put out higher voltage. The volume knob is the variable voltage divider for the out put so you just have to turn it down. Just above unity for a regular amp input ( solid state) or with a tube amp you can turn it up to your liking. If you go to loud it just sounds like poop. You need to use higher voltage caps for everything. 400v caps are good and cheap still. Way more than what you need at 60v but cheap insurance is good. smps can easily put out 200v. be careful and ask a lot of questions. You are in serious risk of being bit hard if you dont. That said, I love high voltage designs. here is an smps amp
Thanks for the reply, that helps loads. And thanks for posting the video clip, your amp sounds great and its very inspiring to see what you can get out of a SMPS. You must be getting at least 50ma, right? To run the 6V6?
I've been reluctant to try high voltage designs for fear of electrocuting myself, but I think a charge pump is a good introduction. Thanks again for your advice.
Just scored 3 NOS 9au7s for $2 each on ebay, shipping included... well see how they are when they get here but since I'm typing I'll go ahead and say that Since no one has really taken the time and made a "full" ... I will soon be posting a full list of all variation on the Valve-Master that one can do... This will include a new on socket drawing and Vero.
I will be testing a few each of 9au7, 12au7, 12ax7, every capacitor with a few values, every resistor with a few values, and a few pot options.
Crunching the numbers that means there are around 816 different combinations... One of those has to sound really damn good... I will of course post my final finding here along with the Vero and "On Socket" Drawing. Also a few other things like were to get great cheap power supplies that will kill all that horrid buzzing without any extra filtering. looking forward to giving back... this project has given me a lot and it only feels right. ^_^
Here is a little something to help those reading through... and wondering what to build... Page 134 has a great thread recap and here is a new UNVERIFIED version of the "On Socket" Version I will be building one from this in a few minutes but here it is all the same.
(http://i73.photobucket.com/albums/i215/Ark-Angel-H-F-B/Guitar%20flash/ValveMasterpcblessdrawing.jpg)
.
Hate making another post but I figured I'd give my trial and error logs so far.
Would put it in the post above but it won't let me edit my post for some reason... weird
Proto Valve Caster #1 Results = Success (Liked T he Sound)
Too much bass/flabby bass, Very sensitive crunch. Organic sounding, but can be too bright.
Not full Distortion gain, just strong OD. Likes single coils pickups better. Sounds best at 9vDC
C1 47nF
C2 47nF
C3 1uF ← value suspected to be to high and store to much bass.
R1 1M
R2 220K
R3 100K
R4/R5 1K
VR1-Gain 50K-A
VR2-Volume 100K-A
Proto ValveMaster #1 Results = Failed
Vero problem, lack of solid wire. Complete lose of board and components on board.
~Solid wire will work better. I'm bad with Vero... really bad...
Proto ValveMaster #2 Results = Success (Did not like the sound.)
Lower gain than Valve Caster #1. Gain seems to act as little more than a less effective volume control. LED added and works. Foot switch added and works. Grounding needs works.
Pedal still too bright or just not enough bass. However Bass flab problem is gone. LED will not light when more than 15vDC is used, while 12vDC is fine.
C1 22nF
C2 22nF
C3 0.001uF ← Suspected cause of lacking bass. Value to low.
C4/C5 10uf
R1 470k
R2 220K
R3 100K
R4 1k
R5 1K
VR1-Gain 500K-A
VR3 100K-A
Proto ValveMaster #3 = Results = Success (Sound is much improved, still very dynamic)
Still very bright, More bass but not enough. Bass can flab/fizz-out just a bit if to much pushed. Responded best at regulated 12.4vDC. Suitable for low breakup jazz. Bass is not tight enough.
C1 22nF ← Consider raising to limit incoming bass in first gain stage (Might fix flabby bass problem)
C2 22nF ← Consider raising to limit incoming bass in second gain stage (Might fix flabby bass problem)
C3 0.1uF ← This seems like the right Value here.
C4 10uF ← Consider dropping to 1uF to let more bass to ground in first gain stage to tighten bass response
C5 10uF ← Consider Raising to hold more bass from ground and up the bass output in the second gain stage.
R1 470k ← Need to test variants
R2 220K ← Need to test variants
R3 100K
R4 1k ←(New R6) 47k Resistor placed after R4&C4, gain/treble less harsh. ( or just up R4 to 47k on it's own...)
R5 1K ← Consider coping above with (New R7) to fully tame Treble and flab-outs. ( or just up R5 to 47k on it's own...)
VR1-Gain 500K-A ← Consider adding (New R8) (470k to 100K) after going to ground to up gain.
VR3 100K-A
@ evilrob. I think im getting around 40 to run that thing. Starving it out pretty good. :icon_mrgreen:
Dear all Matsumin lovers,
Currently I really want to built Matsumin valve caster for my next tube pedal. I have several questions regarding my next built;
1) For me, this thread is huge, I mean, a long way to learn. I have been already read since 2 weeks and still read 'til page 87 (there was something that I've read on page 27-37), and I'm quite confused because there are a lot of good different kind of neat build. So my first question is, what kind of schematic should I use if I want to get brown sound/ lot of overdrive sound ? I saw many build used more than 3 knobs, so I wonder is there any kind suggestion, regarding my next build ?
2) Use of tubes, I also saw in here, there are many options to do with the tubes, in the schematic that was 12AU7, I read also about the NOS 12AU7 would be give good result too, but I don't have it on my hand. I just have 12AX7, could it possible to do in 9VDC ? or should I use SMPS to get the charge pump ?
3) last question, Where can I find SMPS schematic or charge pump schematic for this project ? (I've planned to use madbean roadrage, but if there any related charge pump will work, then I will use and really appreciate it)
Cheers all and sorry for my poor english
welcome fair.child. Your english is fine. Yes this is a huge thread!the murder one sub mini tube amp has a good charge pump to build and so does the gtfo thread. If you want hi gain you may want to look at the gtfo pedal which uses two 12ax7 tubes this pedal is simple and the schematics of the first two pages or so will give you a pedal with some mild overdrive that most people really like. Its a simple build. It uses the 12au7 because of its ability to function even at 9 volts. Some people claim to get more gain and better sound out of 12at7 12ax7 etc. but they dont always work consistently in this circuit. if you have never built with tubes i would try this out stock, then build a charge pump and modify it to get more output and work with other tubes like ax7 etc. after you have learned a little more. Mostly the safety factor involved with higher voltage. if you want to stay lower voltage you can stack 3 of these together and cascade them for some pretty hi gain sounds. not the same as high voltage but not really bad either. just different. you can also put a simple booster ( lpb1 or tillman boost etc. ) and do almost the same thing. Renegadrian has some cool designs for higher gain too. hope that helps.
Quote from: zambo on April 17, 2012, 02:43:33 AM
welcome fair.child. Your english is fine. Yes this is a huge thread!the murder one sub mini tube amp has a good charge pump to build and so does the gtfo thread. If you want hi gain you may want to look at the gtfo pedal which uses two 12ax7 tubes this pedal is simple and the schematics of the first two pages or so will give you a pedal with some mild overdrive that most people really like. Its a simple build. It uses the 12au7 because of its ability to function even at 9 volts. Some people claim to get more gain and better sound out of 12at7 12ax7 etc. but they dont always work consistently in this circuit. if you have never built with tubes i would try this out stock, then build a charge pump and modify it to get more output and work with other tubes like ax7 etc. after you have learned a little more. Mostly the safety factor involved with higher voltage. if you want to stay lower voltage you can stack 3 of these together and cascade them for some pretty hi gain sounds. not the same as high voltage but not really bad either. just different. you can also put a simple booster ( lpb1 or tillman boost etc. ) and do almost the same thing. Renegadrian has some cool designs for higher gain too. hope that helps.
great zambo, and thank you for your welcoming compliment. I came here because my big curiosity building tube pedal.
I've successfully build GTFO by Gabriel T and I saw your post and video related with the tubes. Nice! :icon_smile:
Okay, I wanted to make clearly assumption before I built this pedal
1) I have started over to read again this Huge thread from pages 47-60 to obtain more knowledge about this build. I think 12ax7 is fine to use with 12VDC and it seems quite different than GTFO. More simple than GTFO (this is one of my reason to built this pedal) but I worried with some issues about two 12AX7 will bring me a lot of gain
2) Regarding my first point, I decided to go with your opinion, Zambo. I agreed with mild overdrive, but I will use one 12ax7 (is it okay ?)
3) And yes, Renegadrian has posted some cool designs, triode triode , 6011 high gain , etc. Probably I will go one of his design to build.
4) I look over this thread and saw this
(http://img242.imageshack.us/img242/2053/nouvelleimage1qn4.png)
What is the right value for R1 and R4 ? I wanted to know it, should it around kilo ohms or something ?
nb: I also like the aka_basse build, neat and use 12AX7, I wonder that he would help me to figure out with my build (I want to plan everything correctly) and I should use caps with capable of HV (I mean, above 250V ), shouldn't I ?
and I've found Tim build for valve caster. Looks like neat build and maybe I'll consider to follow him, although I would prefer to use 3PDT than DPDT switch
(http://farm6.staticflickr.com/5134/5518405003_670febf64d.jpg) (http://www.flickr.com/photos/timpatterson/5518405003/)
Valve Caster pedal guts (w/ parts list) (http://www.flickr.com/photos/timpatterson/5518405003/) by Tim Patterson (http://www.flickr.com/people/timpatterson/), on Flickr
Cheers
Quote from: zambo on February 02, 2010, 09:02:44 PM
Hey I ran three valvecasters together and guess what? It sounds awsome! I dropped the input caps to .001uf on the first two ans .022uf on the third. Its still pretty fat. I also ran a 12ax7 in the second stage. Here is a link to youtube clip. http://www.youtube.com/watch?v=L0ZtpJ12C2A . Check it out and please give some feedback. good or bad is fine.
Please share the schematic Zambo... I'm going mad to hear this freaky awesome tone
LOL.. You inspired me to re visit this pedal last night so i did. I will post gut shots and see if I can find the schematic. If not I will redraw it. It will be a bit later today. I will get some video of it today though. :D
this is kind of a ghetto schematic i drew. (http://i1108.photobucket.com/albums/h408/7Ambo707/schematic001.jpg) I didnt draw all the valvecaster parts but this is the order of things. It also shows the input caps I switched out. The most important part is the switching in my opinion. There is a stomp switch for on or bypass and another for one valvecaster or three valvecasters in series. it worked out pretty well although i think i would build it with just one switch thats all three on or off. if i was too use two switches still i would switch between two valvecasters in series or three in series. it would keep the levels more even.
Quote from: fair.child on April 17, 2012, 04:04:44 AM
Quote from: zambo on February 02, 2010, 09:02:44 PM
Hey I ran three valvecasters together and guess what? It sounds awsome! I dropped the input caps to .001uf on the first two ans .022uf on the third. Its still pretty fat. I also ran a 12ax7 in the second stage. Here is a link to youtube clip. http://www.youtube.com/watch?v=L0ZtpJ12C2A . Check it out and please give some feedback. good or bad is fine.
Please share the schematic Zambo... I'm going mad to hear this freaky awesome tone
Just note tone is in the fingers, you could have the same amp and the same guitar and the same pedal and not sound anything like Zambo... I know I have tried.. he oozes blues, which I do not,
Just be warned..
Quote from: zambo on April 17, 2012, 12:02:41 PM
LOL.. You inspired me to re visit this pedal last night so i did. I will post gut shots and see if I can find the schematic. If not I will redraw it. It will be a bit later today. I will get some video of it today though. :D
hey zambo, thanks for your great post, Now I take a deep look into your schematic and learn to do it. It seems pretty complicated for new comer person like me LOL, but I tried to understand. Several questions come to my mind:
1) Did you use one of renegardian or dano valve caster schematic on V1 and V2 ? I guess or maybe one of them will work with it, so I saw and realized that sound came from two 12A_7 (X or U ? ??? I believe they are U's) but I tried to use single 12AX7 on my next build.
2) Is that okay if I use 100V value for caps, I heard it is a high voltage, should I swap it to higher value ?
Thanks in advance Zambo
Cheers all
Quote from: fair.child on April 18, 2012, 12:07:22 AM
2) Is that okay if I use 100V value for caps, I heard it is a high voltage, should I swap it to higher value ?
Depends on the voltage you're using - just make sure you're under the limit, say a 10-15% less, so up to 85/90V to be safe.
Quote from: Renegadrian on April 18, 2012, 05:42:37 AM
Quote from: fair.child on April 18, 2012, 12:07:22 AM
2) Is that okay if I use 100V value for caps, I heard it is a high voltage, should I swap it to higher value ?
Depends on the voltage you're using - just make sure you're under the limit, say a 10-15% less, so up to 85/90V to be safe.
I will use as your recommend 12VDC, then it would be ok 100V -250V, okay, Thank you for your confirm adriano :) glad to hear it from you
if you're running the whole ckt at 12V you don't have to worry then! Glad if I can help somehow!!!
Ahhhh, feel the love in this room :D sorry for my tardiness! I ended up using 12au7's in all three spots. I also used the dano on valve diagram. Still debating how good of an idea that was. Good for one valve but bad for 3 i think. I would use a board layout if I were to build it again I bet you could do it on vero. Either way if you do it use sheilded wire for your signal path as much as you can and be neat about your wiring. They have a tendency to oscilate or ring even when the pedal is off if you dont. If you are doing a one tube project for now, just do a single valvecaster at 12v and if you want more gain stick a boost in front of it like the tillman boost or the lpb1. I m building an sho with a irf510 mosfet right now for just that reason. Its a little dark for my taste. May try the fetzer valve....I digress.
The input caps are all . on all three tubes and the cap between pin 1 and pin 7 is a .022uf on all three tubes. I think you can leave out the 1uf on all of them execpt the last one. It filters out all the dc.
Iccaros is right by the way, Im not saying Im all that :icon_redface: ... but i will say I wring the living !@#$ out of my strings when I play because I have to to make the harmonics etc. jump out. Its maybe not as high gain as you suspect. Hope this helps. Still trying to make a sound clip but got super busy. Cheers!
So Here what I've got so far
(http://farm8.staticflickr.com/7037/6971370596_7725f5f357_z.jpg) (http://www.flickr.com/photos/75813062@N05/6971370596/)
IMG_0649 (http://www.flickr.com/photos/75813062@N05/6971370596/) by DIY Parts + PCB Center (http://www.flickr.com/people/75813062@N05/), on Flickr
(http://farm8.staticflickr.com/7256/6971369038_c9b6c1d87c_z.jpg) (http://www.flickr.com/photos/75813062@N05/6971369038/)
IMG_0653 (http://www.flickr.com/photos/75813062@N05/6971369038/) by DIY Parts + PCB Center (http://www.flickr.com/people/75813062@N05/), on Flickr
I used 68nF into my SPDT (should be 47nF, but I don't have it on hand so probably the best catch is 68nF)
(http://farm8.staticflickr.com/7275/6971362362_34d0f16d14_z.jpg) (http://www.flickr.com/photos/75813062@N05/6971362362/)
IMG_0645 (http://www.flickr.com/photos/75813062@N05/6971362362/) by DIY Parts + PCB Center (http://www.flickr.com/people/75813062@N05/), on Flickr
Little Mess around here for testing
and Finally,
(http://farm8.staticflickr.com/7262/7117458083_f86d8d0f04_z.jpg) (http://www.flickr.com/photos/75813062@N05/7117458083/)
IMG_0655 (http://www.flickr.com/photos/75813062@N05/7117458083/) by DIY Parts + PCB Center (http://www.flickr.com/people/75813062@N05/), on Flickr
(http://farm8.staticflickr.com/7277/7117456571_c85512a8a6_z.jpg) (http://www.flickr.com/photos/75813062@N05/7117456571/)
IMG_0654 (http://www.flickr.com/photos/75813062@N05/7117456571/) by DIY Parts + PCB Center (http://www.flickr.com/people/75813062@N05/), on Flickr
RESULT based on my opinion;
1) This is not a high gain pedal, and it's true but I love it does, it has a some kind of bluesy tone with it. Nice stuff
2) I've got 68nF, which means higher than based on schematic (I used valvecasternylayoutmkabler.jpg and tried to combine it with 7812 schematic and mods) and it sounded better with 68nF (I realized more gain on it) so I just leave it with 68nF
3) grounding and shielding are important, I realized that I've got big hum when I didn't put shielding on it, so I tried to shield the cable, then solved....
Please if there any suggestions or comments let me know, because I'm to excited to build valvecaster again :) and surely, with some correction from my previous built
Cheers all
My single suggestion:
Go on ebay and purchase an RCA 12au7a. sometimes they are relabeled Conn brand, with orange ink. To make sure it's an RCA it should have the 12au7a etched inside a little oblong stop sign with "u.s.a." etched underneath it.
These old RCAs sound incredible. The clear tops look cool but the regular looking tubes (getter flash at the top) work just as well. I honestly think these tubes really wake up any valvecaster. You can get them for about 10$-15 each shipping included if you look around.
+ 1 on the old conn tubes. Love them. Baldwin too.
I snagged several out of an old Lowery, all branded with the Lowery logo.
Couple of questions!
Question 1I built a Valvecaster using a PCB design i knocked up and im having switchmode powersupply noise issues that i cannot seem to filter out.
Any other pedal, no worries at all but this one (breadboarded, PCB, Protoboard etc) ALL let through the powersupply whine.
Its becoming irritating that i cannot seem to filter out the noise.
Question 2My PCB is a tad too big for conventional boxes, any ideas on something suitable and readily available for this ?
BB and B boxes are too shallow for what i need.
(http://tinyurl.com/77td5w9)
Sidenote: Here is my band using the Valvecaster inline with marshall dsl 100 as a fifth tube. THe marshall was set to a gain of about 10 oclock and the valvecaster test pedal was used to provide extra gain for solos and heavier rhythms
radioshack sells a larger/deeper aluminum project box. i don't use them much, but i did build a cacophonator in one. look it up online and see if it might be something you're interested in.
@wizbey
have you tried another tube? what power supply are you using? and are you boosting voltage?
is it too big for a 1590BB box?
Quote from: iccaros on May 08, 2012, 01:12:28 AM
@wizbey
have you tried another tube? what power supply are you using? and are you boosting voltage?
is it too big for a 1590BB box?
The pcb is about 5mm too wide for the depth of a BB box. wanting somthing slightly deep than a BB so i can keep the tube inside while having the pots mounted on the top.
Ive tried all sorts of tubes and they are all the same. The powersupply is a cheap switichmode power supply from a local electronics retailer here and has
variable voltage select (3, 5, 7.5 ,9 as 12). My regular power supply (fueltank jr) for my pedal board doesnt have 12v outputs so ive been using this spare and only one i have.
got ya, on pedal layout..
I pick up supplies at goodwill for $3, you might find a better supply there. you may have to cut and reverse polarity for the end.
this may not be wide enough.. but this kind of ideal may work
http://www.ebay.com/itm/DIY-Boutique-Stompbox-Pedal-Enclosure-/120904368822?pt=Guitar_Accessories&hash=item1c267642b6#ht_859wt_932
Check out the bud industries Cu-471 their a bit deeper/taller i think hammond makes a few 1590 style boxes that are tall
http://www.mouser.com/ProductDetail/Bud-Industries/CU-471/?qs=2dKpBcWpADa%252bRfA0pC%2fP5utTSYBx7QDi8i8EWM5GJHg%3d
just used a few of these ^ they are good size lil deeper then the BB but not as big but close, measure your stuff and check em out they actually make a bucha different sizes in this series.
http://www.mouser.com/ProductDetail/Hammond-Manufacturing/1590X/?qs=NiR3biyRQFf%252b7g7KjTzAmpLmLyCrmHjI9o3yh2WM9F4%3d
Something like that
For the hum, I noticed I get hum with my 12bh7s and not with my ax7s or au7s and it may be because my power supply isn't putting out enough miliamps for the bh7s I think they need more current. I probably need a new better psu as well. Im using a sketchy 18v thats a lil light on the ma. Seen some 12v neg-center on ebay for a good price gonna check out soon.
http://www.ebay.com/itm/400079334083?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649
My first tube pedal build, the ValveMaster.
(https://dl.dropbox.com/u/5675662/ValveMaster.jpg)
Went for the tone knob. Might throw in some input cap switching. Needs a nice paint job, which may be beyond me. Needs better knobs.
Changed up the C & R values a little, so C1 is 22nF and R2,3 are higher values, maybe 64K.
Want more gain - the volume knob basically stays pinned. 12V wall wart supplies the power. It was cheap, but is surprisingly quiet. I get some pot noise off both volume and gain; not sure how to address that and too tired right now to crawl back through the thread to find the fix.
I like the sound. No flabby bass. Breaks up nicely, even in front of this modelling amp.
Thanks to everyone who helped, Rick Holt for the design, Renegadrian for the Vero layout and to the previous 148 pages of contributors.
Mulling over what should be build next.
Nice job! :icon_wink:
Okay...I've figured out what my next build will be: A Twin ValveMaster (TwinMaster? DualMaster?).
Here's the original circuit:
(http://dl.dropbox.com/u/967492/Valve%20Master.JPG)
Would like some help straightening out my plan on it though...
If my thinking is correct, I should be able to simple double up the Vero layout, passing the output of the C3 1uF cap to pin to a 47nF cap on pin 2 of the second tube and into the second copy of the circuit.
The Gain control doubles up in the same location. The Tone control moves to the output of C3 in the second circuit (C7, I suppose) and the Volume pot moves as well.
Questions:
1. Are the assumptions above correct? If not, what changes will I need to make.
2. I'm assuming that keeping the Gain controls is the right thing to do, as opposed to keeping the Volume control on the first tube, right?
3. In the fantasy dreamworld in which I live, I want to add a second footswitch to it, but I'm not clear how to wire it. Looked at the TwinCaster schematics, but they're single footswitch too. Each footswitch would kick in the gain from each tube, the idea being that with the first tube in, I get the creamy, light breakup, with the second, I get a more overdriven sound. Can anyone point me to a schematic that does this?
4. Any point introducing a little bias pot for each tube? If so, where would I do that and roughly what value would I use? I've read that the 12AU7 is self-biasing, so maybe this is moot.
An interesting thing I've noticed: I bought some new 12AU7 for this and swapped them into the ValveMaster and noticed how much quieter they are than the older tube. I guess tubes get louder over time, or maybe there's a burn-in period where the tube becomes more efficient?
Thanks!
yes is the answer to your questions. With a good power supply you can do a lot of different things with this design and its pretty safe. That being said, make sure you have a good cap on the input and output of whatever circuit you come up with. Also, when you double up the tubes you get a bit more output and its to much for some amps. I dont know it will hurt them but I think its safe to assume that overdriving the input of an amp can mess things up if its too much. for switching just make it a true bypass system because its easy. the first switch is on or bypass. When its on, feed the signal to another valvy that is on or bypass. the out put retuns to the first switch. You end up with on/off and a more/less set of switches. I have a schematic here somewhere but dont know where. here is kind of a crappy idea of what im talking about :icon_smile: http://i1108.photobucket.com/albums/h408/7Ambo707/schematic001.jpg
I made mine with 3 tubes. If you want distortion 3 tubes is about the minimum in my opinion. If you just want slight overdrive and more than slight overdrive, two is good. Your caps will probably need to be smaller to compensate for the added bass and teble fizziness can be controlled with the tone knobs. 500pf and .001uf caps across the plate resistors work well too for controlling fizz. .002 is nice on the input caps. Hope that helps :icon_smile:
Quote from: zambo on July 01, 2012, 11:35:14 PM
yes is the answer to your questions. With a good power supply you can do a lot of different things with this design and its pretty safe. That being said, make sure you have a good cap on the input and output of whatever circuit you come up with. Also, when you double up the tubes you get a bit more output and its to much for some amps. I dont know it will hurt them but I think its safe to assume that overdriving the input of an amp can mess things up if its too much.
Gotcha. I don't think I'm in danger of this, but I'll keep an eye open for it.
Quote from: zambo on July 01, 2012, 11:35:14 PM
for switching just make it a true bypass system because its easy. the first switch is on or bypass. When its on, feed the signal to another valvy that is on or bypass. the out put retuns to the first switch. You end up with on/off and a more/less set of switches. I have a schematic here somewhere but dont know where. here is kind of a crappy idea of what im talking about :icon_smile: http://i1108.photobucket.com/albums/h408/7Ambo707/schematic001.jpg
HAH! I was looking at your sketch earlier. I think it's absolutely what I'm looking for. Any chance you could draw it more clearly? I can't reliably see which traces go where and I don't understand the nomenclature of where the pin outs go on VC1 to VC3.
Quote from: zambo on July 01, 2012, 11:40:21 PM
I made mine with 3 tubes. If you want distortion 3 tubes is about the minimum in my opinion. If you just want slight overdrive and more than slight overdrive, two is good. Your caps will probably need to be smaller to compensate for the added bass and teble fizziness can be controlled with the tone knobs. 500pf and .001uf caps across the plate resistors work well too for controlling fizz. .002 is nice on the input caps. Hope that helps :icon_smile:
Have a look at this. It's not verified, but I think it's accurate. The parts values follow the original ValveMaster, not my mod to it.
(https://dl.dropbox.com/u/5675662/20120701-ValveMaster-UnV.png)
Parts List(https://dl.dropbox.com/u/5675662/Screen%20shot%202012-07-01%20at%209.02.49%20PM.png)
it looks correct at a first glance - thanks for citing me in the layout! :icon_wink:
This is very similar to something we did ages ago. I think it's lurking deep in the resesses of this thread but it bears posting again.
Though we run the plates using a charge pump to get a bit more headroom (worth doing).
This is the one we used when we ran them from a 12v supply with pump:
(http://juansolo.demon.co.uk/stompage/schematics/Valve%20Casters/BoobTubeSchematic.jpg)
Then we have the ones that run from a 9v supply:
(http://juansolo.demon.co.uk/stompage/schematics/Valve%20Casters/BoobTubeSchematicV2.jpg)
Here's the charge pump we use at the moment which is nice and compact and nigh on 60v for the plates. It's Renegadrians vero with a regulator strapped to it to run the heaters at 6v. The other one has a buffer on as we had some issues once running one valve pedal into another. We just tend to stick a buffer on the output of whichever one we do now.
(http://juansolo.demon.co.uk/stompage/schematics/Misc/666SBB.jpg)
Pretty sure this is the schematic the vero is based on:
(http://juansolo.demon.co.uk/stompage/schematics/Misc/80v%20Charge%20Pump.png)
Another one we did, which has a very different flavour and is every bit as good was the ultra simple BBT. Same power and buffer things apply:
(http://juansolo.demon.co.uk/stompage/schematics/Valve%20Casters/BabyBoobTube.jpg)
We miniturised this also with submini:
(http://juansolo.demon.co.uk/stompage/schematics/Valve%20Casters/TestTubeBaby.jpg)
Then squished it onto a vero, tube is mounted on the back of the board for packaging:
(http://juansolo.demon.co.uk/stompage/schematics/Valve%20Casters/Damien2.jpg)
Finally the last one we did was the BTT, this one's a little more involved:
(http://juansolo.demon.co.uk/stompage/schematics/Valve%20Casters/BoobTubeTwin.jpg)
These are all verified, pics of them over on my site: http://juansolo.demon.co.uk/stompage/toob.html (http://juansolo.demon.co.uk/stompage/toob.html)
juan thx for all the images! guess they can be pretty helpful to someone! :icon_wink:
My brain hurts.
I've been trying to work out zambo's switching, putting into terms that I can understand, but I'm stumped.
(https://dl.dropbox.com/u/5675662/double%20switch.png)
As you can see, I have no clue what to do about the top left of S2. I'm not even sure that the pins are correct as labelled.
Help?
Also, I think that I made a mistake in the TwinMaster. I've got a jumper from the output of Stage 1 to the input of Stage 2, which effectively means that Stage 1 and 2 will always be running, no? So I think I have to remove the jumper and land the output of Stage 1 on S2, which then kicks in and routes it either to the output (Stage 1 only) or to Stage 2, then to output.
Help. Help, help, help.
Hey , sorry i wasnt on yesterday!! I guess I missed this! Ok just aproach it logicly.you have to decide what order you want the boosting to go in. I like to have a vlave caster on and then boost it with another one before it. You want a switch that goes On/Bypass, and another switch for More/Less dirt right? Ok so S1 has the input from your guitar and goes out to S2 which is wired up for valvecater/or bypass. S2 goes out to the other valve caster input ( less dirt) then the return pin of S1 and then the signal goes to output. Does that make sense? So S1 sends your signal straight through ( true bypass) or to S2. S2 sends the signal to a vlavecaster ( the dirty boost ) which then cascades into the other valvecaster ( slight boost) or straight through to a single valve caster which has its output to the return of S1 and then to output. Its a loop with another loop inside. I will draw it out again :icon_wink:
heres a better pic. Ignore the led's for now they are the easy part anyway http://i1108.photobucket.com/albums/h408/7Ambo707/twincasterswitching002.jpg (http://i1108.photobucket.com/albums/h408/7Ambo707/twincasterswitching002.jpg)
It's starting to look like I'm serious about this TwinMaster thing. Got all the fittings in. No board or wiring yet, but it's an incentive to sort the switch wiring and board out.
(https://dl.dropbox.com/u/5675662/DSC_1621.jpeg)
I think the pots, left to right, will be Vol, Tone, Gain, More (Gain 2).
Left switch is In/Bypass. Right switch is More (second gainstage), complete with obligatory, over-the-top white LED, all in a 1590BB box.
zambo: I think I get this drawing.
S2, when out, passes In from S1, across the jumper and into the input from gainstage 2. Gainstage 2's output then lands back on S1 and out to Volume(?)
S2, when in, diverts In to gainstage 1. The output of gainstage 1 is then passed to the input of gainstage 2, which then lands back on S1 and out to Volume(?).
Cool. I think I get this. You're not adding a second gainstage after the first stage, you're adding a gainstage before it, causing it to presumably overdrive the one that's engaged.
Thanks for the help!
zambo,
Here's the complete switching, as I understand it.
(https://dl.dropbox.com/u/5675662/20120705%20-%20double%20switch.png)
Am I getting it?
Looks good to me. Yep you are switching in a stage to overdrive the stage that was on. If you reverse the order it just gets super loud and acts like a volume boost. also nice but not what most people are looking for. If this doesnt give you enough distortion then you can add a solid state boost ( like a fet boost or whatever you like) in front of the boost stage and it should drive it enough to make anyone happy. I did it on a pedal recently and it was pretty mean. I used an SHO type of design only with the irf510 mosfet ( cause you can get it at radioshack) but i am sure there are better ones for this purpose.
QuoteLooks good to me. Yep you are switching in a stage to overdrive the stage that was on. If you reverse the order it just gets super loud and acts like a volume boost. also nice but not what most people are looking for. If this doesnt give you enough distortion then you can add a solid state boost ( like a fet boost or whatever you like) in front of the boost stage and it should drive it enough to make anyone happy. I did it on a pedal recently and it was pretty mean. I used an SHO type of design only with the irf510 mosfet ( cause you can get it at radioshack) but i am sure there are better ones for this purpose.
Yeah, you're right, that's exactly what I'd accidentally done. Overdriving the stage that's already on is what I'm after.
There's a GGG Ross compressor clone before it that is capable of making the signal hotter and puts the existing ValveMaster into OD sooner, so I'll start there and see what happens. Or maybe, I should be putting the tube first and letting it compress naturally, then feeding that to the Ross.
i would go guitar>compressor>tubes>amp, but thats just me. Overdriving the compressor with tubes would be kind of defeat the point. Its an opinion :icon_rolleyes:
Here's my take on the Valvecaster:
Slightly modified schematic with 7pin tubes. 6C4(=1/2 12AU7) and 6AB4(=1/2 12AT7) can be used.
The valves run on 20V, the heaters in series on 12V.
(http://i872.photobucket.com/albums/ab282/kupfer_m/valvecaster1_72.jpg)
Nice job. That's a great looking build. I've got all kinds of questions.
1. How did you do the plate? Etched?
2. How did you mod the schematic?
3. What's the switch do? Input cap switching?
4. How did you form the protection rail behind the tubes?
5. I've tried switching the 12AT7 for 12AU7 and in every single schematic, I get significantly lower output. I'm running everything at 12V. Is 20V the magic?
6. What's the paint?
Hi
Quote1. How did you do the plate? Etched?
Yes, etched with ferric chloride.
Quote2. How did you mod the schematic?
Here's my schematic :
(http://i872.photobucket.com/albums/ab282/kupfer_m/CASTER.jpg)
Quote3. What's the switch do? Input cap switching?
Yes (see schematic)
Quote4. How did you form the protection rail behind the tubes?
It's from an old RF-test set.
Quote5. I've tried switching the 12AT7 for 12AU7 and in every single schematic, I get significantly lower output. I'm running everything at 12V. Is 20V the magic?
I found 20V a lot nicer than 12V but I can't remember having lower output with the 12AT7 type. Will do some tests tonight.
Quote6. What's the paint?
It is a prepainted box I bought some years ago (at tubetown.de I think) and I finally used it!
Regards,
Jim
nice looking build!!
Heh.
The TwinMaster lives.
Just sorted out a blob of solder that was causing troubles with Stage 2.
The sound: It's a little fat on Stage 1, but crisps up nicely with "More" (Stage 2) engaged. The Gain pots make a fair bit of noise when turned, but I suspect that this is "normal" for this circuit. Tone helps tame the highs when More is in play.
The verified circuit, such as it is, is this:
(https://dl.dropbox.com/u/5675662/20120719%20-%20TVM%20-%2006.png)
Switching is per my previous post.
Picture to follow. I daren't post an internal shot, and I'd love to be a good enough player to post a clip, but my wiring skills are on par with my musicianship.
Thanks again to Rick Holte, Renegadrian for the original ValveMaster Vero layout, and zambo for helping me wrap my head around the switching.
Time to beat on this thing and see what sounds I can make.
I'm starting the planning for the Valvemaster build and I came across with one doubt:
- What is the transformer power I need? For the specs of the 12AU7 I've calculated 300mA for the heaters + a maximum of 20mA (max. rating) for the anode. Will I be safe with a 350mA@15V transformer (plus a LM7812+filtering caps)?
I would say 500mA, minimim. Most wall warts are very 'inexact' about what they actually put out. You also lose some power through the regulator. The wall-wart sagging-out can contribute more noise. I use a 1A supply, but wouldn't go lower than 750mA to make regulation easier. Of course, it depends on the quality of the supply - good quality with built-in regulation can be lower current.
Thanks Zipslack. I wasn't talking about a wall-wart, I was talking about building my own power supply from a 400mA@15V transformer plus a LM7812 and the filtering caps. Can go for a bigger one but it's heavier and more expensive.
Quote from: rugeb on March 22, 2012, 07:59:16 PM
For more current in first stage:
(http://www.fuzzface.es/mods/7812+TIP42.jpg)
rugeb: I can't see almost any of the pictures you've posted!
I've been searching better and I've found at a Philips 12AU7 (ECC82) datasheet that at 12,6V the heater need just 150mA, which made me wonder why is everybody so keen on having a high power source (>750mA).
Quote from: JRM on August 06, 2012, 10:16:00 AM
rugeb: I can't see almost any of the pictures you've posted!
SORRY... reposted! (ALL PICTURES)
Thanks Rugeb. :)
Again regarding courrent draw of a valvecaster/valvemaster: I've spoken to a old school electric engineer that is an expert with hi-fi valve amplifiers and he confirmed that the courrent draw of a circuit like this is quite small and we can safely power our valvemaster/valvecasters with a 200/350 mA power supply depending on the voltage we feed the valve heaters (12.6 or 6.3V, respectively). For the guys doing twin or double masters just double your power. This matches with the courrent draw of EHX 2 valves designs, arround 650mA (found in EHX forum).
I always rate my power supplies at 20% more than what I think the draw will be, I do not like a close match as I have found cheep power supplies that get hot or do not supply their max. So for a pedal with 12v heaters and single tube, where you may draw 160ma, your 250ma would be fine, but in reality those are rare where I live, I see 1a and 500ma all over the place, so I just use those.
You're right Iccaros. As I'm building my psu and I've found 200 and 300 mA transformers, it will be easy to build a customized psu. In fact I'll take the oportunity to build a RG's spyder-like multiple PSU for all my pedal power needs. :icon_wink:
Keep in mind, that standalone PCB transformer that is rated to give a certain amount of amps at a certain voltage is basically what you find inside a typical wall-wart. That's why I recommended you go at least 500mA, because by the time you have some drain/loss from the regulator, you may have a hard time filtering the supply or keeping the transformer cool. Although, since it is rated for 350 at 15V instead of 12, I think you'll be okay...just watch for heat.
I'm making my final review for the Valvemaster build and I've came across with this:
Quote from: frequencycentral on December 22, 2011, 01:49:22 PM
2. VR1 pin 1 goes to C2, pin 2 to tube pin 7, pin 3 to ground? Other was round: 1 to ground, 2 to C2, 3 to pin 7
3. VR2 pins 2 and 3 are soldered together and the result goes to ground? Other way round: 1 and 2 soldered together and grounded, 3 to C4
2. This is the same as wiring the VR1/Gain pot: 1 to ground, 2 to tube pin 7 (grid) and 3 to C2
3. If we solder VR2 (tone) pins 2 and 3 together and ground it and solder pin 1 to C4 we get Bass on Full CCW (0 resistance between 1 and 2 of the pot will drain treble to ground) and Treble on Full CW, don't we?
I'm thinking of replacing the plate resistances by 200k trim pots and 1k resistances with 1k trim pots for adjusting the gain to my ears. I think I'll mess with the caps also, specialy C1 and C2.
I've also read that someone placed some small caps in paralel with R2 and R3 but I don't remember with what purpose (and can't find it anymore).
@ Yeahno - Congrats! Yeah scratchy gain pots are normal. Fun pedal though for sure! You should post shots or clips. Its inspiring for people to see!
Finaly breadboard the Valvemaster and it doesn't work at all, only some hum on the amp's speaker :( :icon_cry:
With both Gain and Vol pots on Max, I got the following voltages to ground on the 12AU7 pins:
1: 8,48V
2: -0,503V
3: 0,04V
4: 0 (GND)
5: 12,41V (+)
6: 8,61V
7: -0,509V
8: 2,13V
9: not conected.
Any hints?
Quote from: JRM on October 04, 2012, 09:25:15 AM
Finaly breadboard the Valvemaster and it doesn't work at all, only some hum on the amp's speaker :( :icon_cry:
With both Gain and Vol pots on Max, I got the following voltages to ground on the 12AU7 pins:
1: 8,48V
2: -0,503V
3: 0,04V
4: 0 (GND)
5: 12,41V (+)
6: 8,61V
7: -0,509V
8: 2,13V
9: not conected.
Any hints?
It was a problem of the f*king breadboard!
Now working and... What a sound! I love it. I'll solder it tonight and tweak the trimpot values then to adjust the gain.
I'll add some resistance in series with the gain pot in order to increase the useful range (otherwise with the por full CCW we don't have any gain/sound).
Loved the warm overdrive and cool boost! My amp got LOUD!
Corrected Voltages:
1: 8,35V
2: -0,682V
3: 0,043V
4: 0 (GND)
5: 12,48V
6: 8,77V
7: -0,715V
8: 0,038V
Nice!!!
Hey guy, I'm new here obviously to build my own stompbox ^^
I stumbled across the Valvecaster on the net and I have enough knowlegde how to build/solder ist but I'm lacking the knowledge for the details :/
As I'm bass player (Rickenbacker 4003 with 12kOhms pickups) I don't think the this setup will be the best tonal one http://www.beavisaudio.com/projects/ValveCaster/ and as the search wasn't so lucky I wanna ask you here what parts should i change to make it bass-compatible? Diagrams would be very helpfull! Btw I wanna use it as extra pre-amp/overdrive pedal ^^
Quote from: VintageVenzi on October 09, 2012, 04:17:43 PM
Hey guy, I'm new here obviously to build my own stompbox ^^
I stumbled across the Valvecaster on the net and I have enough knowlegde how to build/solder ist but I'm lacking the knowledge for the details :/
As I'm bass player (Rickenbacker 4003 with 12kOhms pickups) I don't think the this setup will be the best tonal one http://www.beavisaudio.com/projects/ValveCaster/ and as the search wasn't so lucky I wanna ask you here what parts should i change to make it bass-compatible? Diagrams would be very helpfull! Btw I wanna use it as extra pre-amp/overdrive pedal ^^
I think that it should be fine stock. It's been a while since I ran my bass through my Valvecaster (I normal play regular guitar), but my memory is that it sounded great. If anything you might want to substitute a different input cap. You came to the right place, though, because Renegadrian is a bass player and one of the Valvecaster gurus. He should be able to help you out.
Quote from: VintageVenzi on October 09, 2012, 04:17:43 PM
Hey guy, I'm new here obviously to build my own stompbox ^^
I stumbled across the Valvecaster on the net and I have enough knowlegde how to build/solder ist but I'm lacking the knowledge for the details :/
As I'm bass player (Rickenbacker 4003 with 12kOhms pickups) I don't think the this setup will be the best tonal one http://www.beavisaudio.com/projects/ValveCaster/ and as the search wasn't so lucky I wanna ask you here what parts should i change to make it bass-compatible? Diagrams would be very helpfull! Btw I wanna use it as extra pre-amp/overdrive pedal ^^
Hi,
Welcome to the forum!
I would like to point out that cross posting / duplicating posting is frowned upon here. Also when you start a new thread please use a descriptive subject title. "Newbie needs help!" is not appropriate.
I hope you enjoy our community. :) Good luck.
Andrew
Thanks man! yep I'm a bass player and I did use the Valvy on bass with good results...it boosts in a good way, without being "too much" - that in the stock version, but with no tone control.
Quote
Hi,
Welcome to the forum!
I would like to point out that cross posting / duplicating posting is frowned upon here. Also when you start a new thread please use a descriptive subject title. "Newbie needs help!" is not appropriate.
I hope you enjoy our community. :) Good luck.
Andrew
Thank you and sorry about the cross posting won't happen again I promise ;)
Quote from: Renegadrian on October 09, 2012, 08:08:19 PM
Thanks man! yep I'm a bass player and I did use the Valvy on bass with good results...it boosts in a good way, without being "too much" - that in the stock version, but with no tone control.
Well that sounds good for me but do you mean with "boost" also overdrive and do you mean with stock version this http://www.beavisaudio.com/projects/ValveCaster/MatsuminValveCaster.gif ?
P.S. Where should be the footswitch in the plan?
I built a stock Valvecaster per the Beavis schematic. I can see how it would sound great for bass but had too much low end for guitar... it made even my Tele sound muddy even with the tone knob dimed! I brought down the input cap to .018uF and that helped some. I then knocked down the coupling cap to .018uF, but I couldn't tell much difference... I think my ears were tired by that point. ;D
I have a little extra wiggle room in the enclosure... what's the difference between the Valvecaster and the ValveMASTER?
>P.S. Where should be the footswitch in the plan?
Most effects schematics don't show the bypass switch and LED indicator. Here's how you do it:
http://www.generalguitargadgets.com/diagrams/switch_lo_3pdt_ig_dcjack.gif?phpMyAdmin=78482479fd7e7fc3768044a841b3e85a
New member, just finished my first Valvecaster and love it... except for the noise. I picked up a 7812 regulator today by mistake, I needed a 7809 since I'm running 9 volts. Can I still use the 7812 or do I need a 7809?
Quote from: Squirrels on October 15, 2012, 03:48:55 PM
New member, just finished my first Valvecaster and love it... except for the noise. I picked up a 7812 regulator today by mistake, I needed a 7809 since I'm running 9 volts. Can I still use the 7812 or do I need a 7809?
I run mine on 12V with no problem, but make sure the heaters are connected in series (12V across pins 4 and 5 and no connection to pin 9).
The voltage regulator you have, the 7812 needs a minimum of 14 volts I believe. check the data sheets. Your gonna want 12 volts for the heaters and the rest can run higher. So I suggest keeping the 7812 for the heaters and get yourself a power supply that can put out more then 12volts. I think the 7812 max is around 30 volts and min 14volts.
Quote from: Mustachio on October 15, 2012, 07:05:17 PM
The voltage regulator you have, the 7812 needs a minimum of 14 volts I believe. check the data sheets. Your gonna want 12 volts for the heaters and the rest can run higher. So I suggest keeping the 7812 for the heaters and get yourself a power supply that can put out more then 12volts. I think the 7812 max is around 30 volts and min 14volts.
Good point. I should have mentioned that I'm using a 24VAC wall wart. I rectify to DC and regulate in my Valvecaster enclosure.
I'm really new to electronics so I'm unsure what that all means right now. I guess I'll get a 7809 tomorrow in the meantime. I've still got quite a bit to learn... and only a 9V power supply. Thanks.
a 7809 needs a minimum of 11 or 12 volts so if you only have a 9 volt power supply its still not gonna work.
Don't forget to look at the output of the wall warts amps or miliamps ma. 12ax7 and the others that are alike pull about 300ma or so. I think the 12Bh7 pulls a lil more amps. If your walwart cant supply enough amps or its just on the edge you may get some hum/noise from it as well.
Your really better off picking up a 12 or 18 v 1amp wall wart from ebay for 10 bucks or less. If you get a 12v adapter then dont use a regulator because you need at least 12 on the heaters. If your using 14v or more then use the 7812. You really dont need a 7809.
I believe if you feed the heaters only 9v it will possibly not sound good and shorten the life of the tubes. I know this is a big thread but all the answers are in it. You might want to check out the voltage multipliers for the plates since stock this is starved plate.
Quote from: Squirrels on October 15, 2012, 07:41:51 PM
I'm really new to electronics so I'm unsure what that all means right now. I guess I'll get a 7809 tomorrow in the meantime. I've still got quite a bit to learn... and only a 9V power supply. Thanks.
One thing you should know about using 78xx regulators is that the input voltage (Vi) has to be at least 1.5V greater than the output voltage (Vo). If you only have a 9V supply and you try to use a 7809, you'll be disappointed. Ain't gonna work. :(
Before you spend money on certain parts, you need to refer to data sheets to understand what the requirements are for the thing to operate properly. You don't have to look up every 1/4 watt resistor, but semiconductors such as transistors, and integrated circuits are more complex. If you don't understand the data sheet or if you have a question that's not covered on the data sheet, then the forum is here to help you.
Here's the data sheet for the LM7812 (and other 78xx regulators): http://www.fairchildsemi.com/ds/LM/LM7805.pdf
(http://i1160.photobucket.com/albums/q485/jdansti/EEF124FF-27FB-4891-A295-DFB23174A928-7202-000006A48B3F1689.jpg)
The 7812 data sheet says that a Vi of 14V-27V and a current draw between 5 mA and 1A will yield a Vo of 11.4V to 12.6V, with the typical being 12V.
I'm sure we can help you find an option that will work-hopefully low cost (for example, if you could get a used laptop PS at a thrift store that puts out around 18V and 2-4A, it wouldn't cost much to get you to 12VDC). There's a lot of great help here on the forum, and we all want to see you succeed! :)
So I'd have to use an 18v wall wart to use the 12v regulator? Sounds simple enough. Regarding the heaters, I used the layout from this thread:
http://www.diystompboxes.com/smfforum/index.php?topic=99239.0
It worked well besides the noise and blowing an LED since I didn't use a resistor at first. What would I have to change to run at 12v? Also will a 500k or 1meg gain pot increase the overall drive? I'm used to having a TS9 in front of my Dark Terror to push my high gain sound a little more, right now the VC doesn't cut it. With my Strat with a DiMarzio Injector bridge it works fairly well but in my PRS with Dragon II's it doesn't do much... and adds a lot of noise. With lower gain it sounds great.
Thanks for the data sheet for the regulator. I'll read it more tomorrow. After I label it, I'll post a few shots.
One more question, I'm using a "Fender Style" socket with what I'm guessing is another pin in the center. Is that a ground and can it be removed to fit an LED under the tube to light it up?
I think in this thread there's info on increasing gain. I don't remember if it was changing a resistor to the plates or if it was just a larger gain pot. If you read this entire thread by the time you get done you will more then likely have a much better grasp on electronics then when you started. This thread is chalked full of goodness.
The center lug in the tube socket Is not grounded. It holds the tube socket together actually, and if you remove it the socket will come apart. If you remove it just be careful, if it separates you can get it back together with the pins correct and put a lil super glue in maybe. I used large shrink wrap on a tube socket once held it together well. Also try a 3mm led they fit much better in the hole might get away with not removing the metal plug or tabbed insert.
3mm orange high bright looks nice :D
>So I'd have to use an 18v wall wart to use the 12v regulator? Sounds simple enough. Regarding the heaters, I used the layout from this thread:
http://www.diystompboxes.com/smfforum/index.php?topic=99239.0
You need something between 14 and 30ish V. I just mentioned 18V because that's about what many laptop supplies put out (a quick check of a website selling these listed models between 12VDC and 19.5VDC).
Regarding heater voltage, if you look at pins 4 and 5 on the schematic you referenced, you'll notice that 4 is connected to ground, pin 5 is connected to the + side of the power jack, and pin 9 is not connected, so that means that voltage will flow through both heaters in series. Good for a 12V supply.
Here's a more detailed view of a 12AU7 tube.
(http://i1160.photobucket.com/albums/q485/jdansti/0DDE1D56-0ED7-47C0-90CC-405A69E4FB68-7766-0000072383E8DF69.jpg)
If you follow the lead from pin 4, you'll see it goes through the left heater at the bottom, then past a center tap lead connected to pin 9, then through a second heater, then to pin 5.
Each of the two heaters has a max voltage rating of 6V. So if your heater supply is 6V, you could put +6V on pin 4 , +6V on pin 5, and connect pin 9 to ground.
But if you heater power is 12V, you could put +12V on pin 4 and connect pin 5 to ground and vice versa. Since the two heaters share 12V, the voltage drop across each is 6V. Make sense?
Regarding VC gain, it's not a high gain circuit, so you're only going to get so much distortion from it. You have a few options. One is to cheat and use simple diode clipping on the output. Hardcore toobies would not do this, but if you like the sound, go for it. Here's a great write up on the subject with some example circuits: http://www.muzique.com/lab/sat.htm
If you want to stay all toob, check out the dual caster: http://www.diystompboxes.com/smfforum/index.php?topic=89561.0. There's also a Triplecaster somewhere on the forum.
A third option is to try a different tube such as the 12AT7. There is some anecdotal opinion that the 12AT7 has higher gain. The 12AX7 does have higher gain, but most people don't like the sound.
Edit: Removed my nonsensical comment about heater current. :icon_redface:
I could be wrong... but regarding the above post... I'm pretty sure that the heaters take 300ma at 6+ and only 150ma at 12+.
I could be wrong but go read back through the first few pages of the thread and I think that is gone over...
Quote from: Ark Angel HFB on October 16, 2012, 09:41:53 AM
I could be wrong... but regarding the above post... I'm pretty sure that the heaters take 300ma at 6+ and only 150ma at 12+.
I could be wrong but go read back through the first few pages of the thread and I think that is gone over...
Thank you!!! That's what happens when I rely on my memory and don't use Ohm's law or look at the data sheet! :icon_redface:
I'll correct my earlier post.
That makes sense. I just need to learn to do it. I'll be ordering new tubes for my amp soon (hopefully) so I'll try out to 12AT7 and 12AX7 in the VC. I'm using an orange 3mm as the indicator light so I'll try to pop that under the socket and add a 5mm as the indicator. The 3mm is too small anyway. A bigger one would look better.
Will the way I have it wired now handle 12v? I have an 18v wall wart from a Dust Buster I can use until I have a chance to get a dedicated one for my VC. I have to double check it'll fit first. I figure I can put the regulator and cap in and try it out for awhile.
it should be fine... but thing to consider...
Make sure the power pin is tip negative and sleeve positive...
Also the heaters will like 12v not 18v... so you could test it but I don't think it be good for teh tube to keep it that way for very long...
I'd go with an http://www.taydaelectronics.com/ic-integrated-circuits/voltage-regulators/l7912cv-lm7912-l7912-7912-voltage-regulator-ic-12v-1-5a.html for the + that is going to the heaters and the rest is up to you dude... ^_^.
This was the first circuit I ever built... and it is very VERY forgiving... mess with everything it is a lot of fun to try stuff... I suggest keeping a record of things you try out.
I have a 7812 and cap I'm going to put in tonight to try with the 18v wall wart. I'm also looking to add a bright switch. I think that would definitely help with a humbucker.
Quote from: Ark Angel HFB on October 16, 2012, 05:39:39 PM
I'd go with an http://www.taydaelectronics.com/ic-integrated-circuits/voltage-regulators/l7912cv-lm7912-l7912-7912-voltage-regulator-ic-12v-1-5a.html for the + that is going to the heaters and the rest is up to you dude... ^_^.
7
912 or 7
812?
Well, I wired in the 100pf cap to the jack (pos. to pos., neg. to neg.) and then wired the voltage regulator up. Power to leg one, ground to leg 2 and output to leg 3 going to pin 5. In still had the ground from the jack going to original ground on the stereo jack. When I plugged the 18v supply in, the jack arced and then nothing. The tube didn't light up, neither did the LED. I removed the ground to the stereo jack and the LED worked, but no power to the tube and no effect when plugged into the amp. I guess I blew the tube? I'll post gut shots tomorrow, maybe I did something wrong.
Edit-It's late (early) and I didn't read your post carefully. We'll take a look at the wiring and see if we can figure it out.
Hindsight: It's usually best to wire up and test your power supply/regulator before you connect it to a circuit. After we look at the guts, the next step might be to make sure the PS and regulator are wired correctly and then see if that sub-circuit is working independently.
Something else you can do is remove the new PS circuit and try it with 9V like you had it before and see if it's alive.
I wound up removing the regulator and wiring it up back to how it was (except I left the cap in the jack) and it works fine, but still noisy. I should have taken gut shots before I did it, I'm just feeling lazy right now, I'll try it again this weekend maybe. In the meantime I'm just going to enjoy it as is, it sounds great with lower gain amp settings, but it doesn't have enough to push a more heavily driven sound. I'm primarily a metal player, so I was hoping that this would replace my TS9. If I can just get a little more gain and treble response it would be perfect. I play blues and classic rock too and this definitely fits the bill. The VC sounds more natural to me that the TS9 ever did.
I'll definitely be reading more of the complete thread too, the things I'm looking to do are most likely in here, thanks for all your help everyone, I'll check back when I try bumping it up to 12v again.
Quote from: Squirrels on October 17, 2012, 12:27:28 PM
I wound up removing the regulator and wiring it up back to how it was (except I left the cap in the jack) and it works fine, but still noisy.
Try using this on your power supply. It cures the buzz in all of my high gain pedals.
http://www.beavisaudio.com/projects/Huminator/index.htm
If you're looking for higher gain, check out Renegadrian's 'Tube Star', a 12AT7 pedal that uses higher plate voltage.
Quote from: haveyouseenhim on October 17, 2012, 12:37:02 PM
Quote from: Squirrels on October 17, 2012, 12:27:28 PM
I wound up removing the regulator and wiring it up back to how it was (except I left the cap in the jack) and it works fine, but still noisy.
Try using this on your power supply. It cures the buzz in all of my high gain pedals.
http://www.beavisaudio.com/projects/Huminator/index.htm
Other than maybe adjusting the LED resistor, would there need to be any changes to use this with 12V?
Also, does anyone know if this would work well as a small board with heat shrink around it and the leads with jacks/plugs coming out each end? It would look like a power cable with a bump in the middle - no metal enclosure. I'd double the cable ends back under the heat shrink to provide strain relief and I'd probably not use the LED and its resistor.
Now that I've used it some more, I'm not sure it's more gain that I want, I think it's more treble. It sounds great with my Strat, but it doesn't seem very humbucker friendly. I mostly use it to push my Dark Terror harder. Even with the tone control full on it's pretty dark. It sounds great with my Strat. By the way, DiMarzio Injectors are great pickups, very versatile. I can even get a nice metal tone if I turn the tone on the Strat down a bit.
The Huminator seems like a good idea. Would I get the same results with a regulated 9v wall wart?
For now, I'm going to work on labeling it and hopefully have some pics up soon.
Quote from: Squirrels on October 17, 2012, 05:54:02 PM
The Huminator seems like a good idea. Would I get the same results with a regulated 9v wall wart?
It depends on the model you choose. A lot of people like the 1-Spot. I've hade good success with the Danelectro DA-1. I'm sure that there are other good ones, but it would be hit or miss if you were to randomly choose a PS that you haven't heard or that someone else you know hasn't tried.
Hey, guys. I built the valvecaster a few years ago for my bass and loved it but could never get it boxed up successfully. I'm looking to try again but with the Valvemaster schematic. I plan on socketing the input, output, interstage and tone caps so I can play with the values until I find something that sounds great with bass. I also plan on making a PCB for it since I always had trouble with the PTP stuff. It will also help that I have a real soldering iron (WP-25 vs. wal-mart/sears crapo iron) this time along with lots of practice repairing cables and such.
My question is what do the capacitors on the cathodes do? Would it make any difference playing with their values? I would imagine it has something to do with biasing the voltages or something. Sorry for the ignorance. I know just enough to be dangerous. lol!
It makes a big differences...
The reaction seems to be the lower the value there... the more bass in the signal. but if you go too high it starts getting bad.
For guitar I went with 1uf...
I'd say for bass you should consider getting 0.1uF, 1uF, 4.7uf, and 10uF so you can play with the values.
Also the relation of R4/R5 is that lower values ups gain and volume massively... trying 0, 560ohm, 1k. are worth it.
R2/R3 also play a role in the gain... lower values give more of a clean sound... while higher value give more drive. All values from 22k to 220k are worth looking at.
You cna also look to mess with the Gain knob by adding a small resistor after it going to ground on its ground line. like 22k to 47k. This will give slightly more gain and mean when you turn the gain down all the way the pedal doesn't stop making noise. a good Idea may be to find what is the lowest setting of gain you like and put a resistor there with that value. then a pot in front can only drop the gain to the amount you like.
Lastly grab a EQ circuit... http://www.muzique.com/lab/atone.htm this works great for taming the bass or cutting treble... I'd put it after the circuit, this is where I put mine for best results.
or... http://www.muzique.com/lab/swtc.htm. have not tried it but I plan too.
These things sound awesome when you get them up above 45 volts or so. they have more mids, better bass more head room and will push an amp much harder. Changing the caps on the input and output and from pin 1 to pin 7 to smaller caps makes them much more humbucker friendly even at 9 or 12 volts imho. try .0022 on the input and pin 1 caps and .022uf on the output. starved plate low voltage tubes have to much bass and mushy fizzy highs for the most part. sounds good clean to mildly dirty. when you start cascading these together like the valve master etc. you have to really tame the bass and the highs. 500pf and .001uf caps on the plate resistors help the highs roll off combined with smaller caps leaves the mid boost that you need. that being said, looking at voltage multipliers and running them at higher, but not to scarey voltages seems to work the best.
Quote from: zambo on October 25, 2012, 07:27:50 PM
These things sound awesome when you get them up above 45 volts or so. they have more mids, better bass more head room and will push an amp much harder. Changing the caps on the input and output and from pin 1 to pin 7 to smaller caps makes them much more humbucker friendly even at 9 or 12 volts imho. try .0022 on the input and pin 1 caps and .022uf on the output. starved plate low voltage tubes have to much bass and mushy fizzy highs for the most part. sounds good clean to mildly dirty. when you start cascading these together like the valve master etc. you have to really tame the bass and the highs. 500pf and .001uf caps on the plate resistors help the highs roll off combined with smaller caps leaves the mid boost that you need. that being said, looking at voltage multipliers and running them at higher, but not to scarey voltages seems to work the best.
What is your charge pump configuration?
The way I see it there are two good options...
Option 1: (9v in) Doubled to 17.5, doubled to 33.3. Power taken at the 17.5 area regulated down to 12 v for heaters.
Pros: Common 9vDC guitar pedal power supplies can be used and this is convenient.
Cons: Will be drawing a good amount of mili-amps and some of the common 9vDC power supplies can't handle that and might fail.
Option 2: 15vDC supply regulated down to 12vDC for heaters. Then 12vDC doubled to 22.5, doubled to 41.5.
Pros: More simple, and only one double is needed to get into a higher volt area of 22.5. Less risk of power supply failure
Cons: Means a dedicated 15vDC supply would have to be used. This is less convenient.
Thoughts?
ive done it a bunch of different ways but my fav is to use the max1044 type charge pump ( i use lt1054 from small bear as it seems to be a better product and I like to support members when i can :icon_cool: ) the murder one uses it i believe. So i power the heaters off of a 1spot 9v thats split into A) 9volts to charge pump B) 9v to a regulator or dropping resistor for heaters. The charge pump is hooked up to the plates and voila. The other way is to use an smps but thats more tricky and i dont think its really worth the effort. I would use the same method of splitting the power supply etc. just replace the charge pump with smps. gets 200v that way. Danger! :icon_eek: you have to use parts rated for it etc. and the layout and wiring are a bit different from stock. The 1044 type charge pump is best in my opinion because of the lower voltage. keeps it in the beginner tube project realm. For 24 volt operation just use a laptop power supply and split it to a regulater for the heaters ( lm317 works i think) . for whatever thats worth :icon_wink: The beauty of this project stock is its simplicity. If you want more gain and straight up distortion a new design is better. for just beating an amp into over drive a 45 volt version is cool. keep the tone knob in the design as amps get fizzy when pushed and taming the highs is nice.
so you drop the volts to 6 and then run the heaters off of that 6vDC at 300ma... hmmm... yeah that would work... and then the 9vdc could just be X3'd or X4'd up to whatever you want... sounds solid...
Now the real trick is to see if it can all fit inside a 125B box... XD might have to forgo having a battery... build everything on the tube socket... maybe find a smaller tube socket while I'm at it... what a challenge. ^_^
I want the tube inside the pedal so this might be hard to pull off, with three to four pots... should be crazy, might have to have some pots on the side of the pedal at the top.
you could just get some sheet metal and make a box :icon_wink: Home depot has sheet aluminum so does ace hardware. pretty easy to bend up a two piece box. having the tube inside is nice but you do have to vent it. Ive built them with 3 tubes inside before but only running at 9 volts. they get a bit hotter at 45 or so.
Venting you say.... >_>
guess that wouldn't be to hard to drill a few holes on the side...
If I wanted to mount the tube inside what would the best way be?
Quote from: zambo on October 28, 2012, 02:17:23 AM
you could just get some sheet metal and make a box :icon_wink: Home depot has sheet aluminum so does ace hardware. pretty easy to bend up a two piece box. having the tube inside is nice but you do have to vent it. Ive built them with 3 tubes inside before but only running at 9 volts. they get a bit hotter at 45 or so.
How did you mount it inside? pics?
I used an L bracket with a hole for the tube socket. bolted the other side of the brcket to the inside of the enclosure. Just drill holes in the sides and or top of the box for venting. Keep the tube away from any solid state parts if you run a voltage pump etc. Using sheilded wire for the long signal leads is a beautiful thing. Here is a vc running at 81v into a 1/4 watt tube power amp. :icon_eek:
Hi all, I'm new to the forum and new to pedal building, I've made one of the simple boost pedals and I'm now wanting to try the schematic from the first page, I understand all the schematic but, and you will have to excuse me if this is a silly question, why does it show 2 tubes in the schematic, is it just the other connections on the same tube but split in two on the drawing to make it easy to see ? , cheers in advance for any help.
Quote from: Spankyspangler on November 05, 2012, 04:59:04 PM
Hi all, I'm new to the forum and new to pedal building, I've made one of the simple boost pedals and I'm now wanting to try the schematic from the first page, I understand all the schematic but, and you will have to excuse me if this is a silly question, why does it show 2 tubes in the schematic, is it just the other connections on the same tube but split in two on the drawing to make it easy to see ? , cheers in advance for any help.
You are correct that the schematic shows two sections of the same tube separately. There are two triodes in the 12au7 tube. See:
http://en.m.wikipedia.org/wiki/12AU7
(http://i1160.photobucket.com/albums/q485/jdansti/47074CDA-1145-434F-A089-F2DEFBC57AC5-4136-000003BD63C4DDDB.jpg)
Brilliant, thanks very much for that
Well as of right now this is were my Valve-Master Project Stands...
Below is not verified...
(http://i73.photobucket.com/albums/i215/Ark-Angel-H-F-B/adsfwwf.png)
Ok things to note...
1. C4/C5 can be left off as it sounds fine without them
2. R4/R5 sound good anywhere from 1k to 0 (they effect gain and volume greatly)
3. R2/R3 sound good anywhere from 1k to 100k (they effect and volume greatly)
4. D1/C6/C7/R6 Form very basic power filtering plus reverse polarity protection. http://www.beavisaudio.com/projects/Huminator/index.htm
5. I leave an extra space after the hook up cables in purpose sp you can drill through the boad there and run the wire through so that the solder joint is never stressed.
6. The Tone Shaper is this http://www.muzique.com/lab/swtc.htm
7. This may come in handy for getting R2/R3/R4/R5/C4/C5 tuned to the correct values... http://www.ampbooks.com/home/amplifier-calculators/cathode-capacitor/
(C4/C5 are each one CK) (R2/R3 are each one RL) (R4/R5 are each one RK)
8. C1/C2 Higher value like 22nF also works but the bass can get out of hand fast...
I hope this helps... the real battle with this pedal will be tuning the amount of volume increase while still preserving the quality of the sound... will have more for you guys later.
I just got my Valvecaster up and running, but I think it sounds a bit weak. I built in a switchable SHO boost in front of it but with everything at max my clean signal is still louder than the signal through the pedal. I just want to clearify that the pedal should increase the volume, right?
What could cause this volume drop? Faulty tube? I've checked for reversed pot connections but everythings seems to be correct.
I'm using a JJ ecc82 tube and the pedal runs on a fresh 9v.
Any suggestions? I want loud pedals! :D
Quote from: KNA on November 18, 2012, 03:52:55 AM
I just got my Valvecaster up and running, but I think it sounds a bit weak. I built in a switchable SHO boost in front of it but with everything at max my clean signal is still louder than the signal through the pedal. I just want to clearify that the pedal should increase the volume, right?
What could cause this volume drop? Faulty tube? I've checked for reversed pot connections but everythings seems to be correct.
I'm using a JJ ecc82 tube and the pedal runs on a fresh 9v.
Any suggestions? I want loud pedals! :D
Frist let me say this... something is wrong. This pedal is the loudest pedal I've every seen.... it can give almost as much as 40+ db of boost.
Ok a few questions...
1. What values are you using for everything... A wrong value in one place can dropped the volume massively
2. Do you have more than one tube to test in the circuit.... if not get more.
3. What layout did you use.
Quote from: KNA on November 18, 2012, 03:52:55 AM
I just got my Valvecaster up and running, but I think it sounds a bit weak. I built in a switchable SHO boost in front of it but with everything at max my clean signal is still louder than the signal through the pedal. I just want to clearify that the pedal should increase the volume, right?
What could cause this volume drop? Faulty tube? I've checked for reversed pot connections but everythings seems to be correct.
I'm using a JJ ecc82 tube and the pedal runs on a fresh 9v.
Any suggestions? I want loud pedals! :D
In addition to what Ark Angel recommends, double check your battery voltage with the pedal powered up. Also, try temporarily separating the output of the SHO from the input of the Valvecaster and check each circuit independently. This would help you to cut the problem in half. If you have low volume from both sub-circuits, then your problem is common to both.
Quote from: Jdansti on November 18, 2012, 05:11:30 PM
Quote from: KNA on November 18, 2012, 03:52:55 AM
I just got my Valvecaster up and running, but I think it sounds a bit weak. I built in a switchable SHO boost in front of it but with everything at max my clean signal is still louder than the signal through the pedal. I just want to clearify that the pedal should increase the volume, right?
What could cause this volume drop? Faulty tube? I've checked for reversed pot connections but everythings seems to be correct.
I'm using a JJ ecc82 tube and the pedal runs on a fresh 9v.
Any suggestions? I want loud pedals! :D
In addition to what Ark Angel recommends, double check your battery voltage with the pedal powered up. Also, try temporarily separating the output of the SHO from the input of the Valvecaster and check each circuit independently. This would help you to cut the problem in half. If you have low volume from both sub-circuits, then your problem is common to both.
I get the feeling you think he may have a power supply problem... a bad battery, or power supply will cause problems...
Quote from: Ark Angel HFB on November 18, 2012, 04:59:30 PM
Frist let me say this... something is wrong. This pedal is the loudest pedal I've every seen.... it can give almost as much as 40+ db of boost.
Then I'm off to debugging! I used this design: http://juansolo.demon.co.uk/stompage/schematics/Valve%20Casters/LPB+Valvecaster.jpg
Seems like I mixed up the SHO with the LPD boost, sorry for that. It's the LPD I'm using.
If I'm not mistaken the design is the same as the one used by many earlier in this thread, so it should be verified. I have also compared the boost design to others and it seems to be verified as well. I used sockets for all the caps to allow some tweaking. I havent triple checked the resistors though. I also read on another forum that changing the volume pot to 50k should increase the volume, but I think my problem is bigger than that. Off to ebay for another tube I guess. Thanks for your help so far!
I will be honest... I think the valve master is far better than the valve caster.
that being said... if you wish to keep the what you currently have and just tweak it and let us help you... Try this for me.
1. FRIST!!! Take voltage reading of your power supply both with load and without.
..... THEN power reading from every pin. (Do this by grounding you black lead on your multi meter and touching the red one to the different areas.)
2. If possible i'd also like to ask that you try the layout I posted at the top of this page. Just skip the tone shaper part of the circuit. it isn't working how I wanted.... it isn't bad... but there are other options.
Then the Valve master is in line for future projects!
So here are my results: Battery without load: 8,2v. With load: 6,8v
Pin 1: 6,5v
Pin 2: 0,03v
Pin 3: 0,0v
Pin 4: 0,0v
Pin 5: 6,7v
Pin 6: 6,5v
Pin 7: 0,03v
Pin 8: 0,0v
Pin 9: 3,2v
I've compared the results to others earlier in this thread and it doesn't seem quite right. I also double checked the resistors and all four is correct. New tube? Would be an easy solution ;D
What bothers me most in this is that this is the simplest cicuit I've built but it's still the one that has caused me the most trouble.
Quote from: KNA on November 20, 2012, 12:25:45 PM
Then the Valve master is in line for future projects!
So here are my results: Battery without load: 8,2v. With load: 6,8v
Pin 1: 6,5v
Pin 2: 0,03v
Pin 3: 0,0v
Pin 4: 0,0v
Pin 5: 6,7v
Pin 6: 6,5v
Pin 7: 0,03v
Pin 8: 0,0v
Pin 9: 3,2v
I've compared the results to others earlier in this thread and it doesn't seem quite right. I also double checked the resistors and all four is correct. New tube? Would be an easy solution ;D
What bothers me most in this is that this is the simplest cicuit I've built but it's still the one that has caused me the most trouble.
It looks to me like you're battery is too low. Try a fresh 9V battery or two fresh 9V batteries in
parallel (not series!). I think that the heaters drain 9v batteries pretty quickly. The other thing you could do is use a 12vdc PS. That's what I'm using and it works great since the heaters are rated at 12v when both heaters are used in series. I assume that you're heater voltage is connected through pins 4 and 5 and no connection to pin 9.
Success!!
I tried to run it on 9v through an adapter, and now it's loud! Never thought a few decivolts could do that much difference. Huge thanks for the help! See you soon in the Pictures thread...
Glad you got it going! :)
...Name of this topic is misleading...It should be changed to Tube boost + overdrive running off a 1A 12V wall wart
500mA should be good too, but 1 is to be safe.
Quote from: Renegadrian on November 21, 2012, 07:01:35 PM
...Name of this topic is misleading...It should be changed to Tube boost + overdrive running off a 1A 12V wall wart
500mA should be good too, but 1 is to be safe.
Lol I know right.
Hey there everyone! Over 150 pages of work thus far, mighty impressive.
Many of us have built more than one Valvecaster with our personal tweaks, maybe we can re-consolidate our efforts, to save some massive page sifting? For newcomers and returners alike.
Also, I found this link online, and was wondering if anyone has morphed this variation into a Valvcaster as yet? http://www.freewebs.com/valvewizard2/Triodes_at_low_voltages_Blencowe.pdf (http://www.freewebs.com/valvewizard2/Triodes_at_low_voltages_Blencowe.pdf)
I'll be making attempt #2 at getting the above link working in a Valvecaster today, and will post my results.
I experimented with the fender bassman input stage - quite decent booster!!! very loud!
It is similar - a gain stage and a "buffer" stage. Try it!!!
@Tony E. Regarding the 'saving from massive page-sifting', I think Aron did that a while back...printed out to about 12 pages if memory serves. I'll try and look it up, if no one else jumps in about it.
@Adriano Nice to see you're still 'riding herd' on this thread... :icon_biggrin:
Larry
Okay...go back to page 134...posting by rotylee, reply #2660. Aron's summary pdf and other links. Larry
2nd run thru worked like a charm! Will post my schematic soon as I can remember how to post pics. For my 12V Valvecasters that didn't use a charge pump to boost the Plate Voltage, the sound was very good.
From my previous link at http://www.freewebs.com/valvewizard2/Triodes_at_low_voltages_Blencowe.pdf (http://www.freewebs.com/valvewizard2/Triodes_at_low_voltages_Blencowe.pdf)
I have successfully implemented this configuration into a Valvecaster. Here's the schematic of my verified version.
(http://img94.imageshack.us/img94/3606/buffbsvalvecaster.png)
Sound samples and effect of the boot strap?
I don't have a good recording rig, so I'll have to charge up my video camera recorder. Sound samples soon. Though I apologize in advance for my playing skills, be forewarned!
I'll say this much... after a little testing I'm just very very shocked that no company does this kinda simple pure pedal... they sound so much better then diode clipping and what not.
Tubes for the win...
Also, and this has more to do with general pedal construction... If you are not using regulated power supplies I highly suggest that every pedal you built has the following in the circuit.
(V In) -> 100ohm resistor -> 470uF cap to ground (Optional 220uF cap to ground) -> (V Out to circuit) Add this to the start of every circuit and power supply noise will be a thing of the past... Also don't forget that until you get something inside a box... it can have hum/hizz/buzz from junk signals that are in the air... so it might hum/hiss/buzz just from being outside the box.
I think everyone who's built this project has a better understanding of power supply hum issues than before they started. I've had hum probs in non-tube pedals, fizzy and whatnot. But if you don't filter the power for tube heaters, you get some REAL HUMMERS! My first build got all the dogs on the street barking at once before I dropped a 7812 in there to regulate the power.
I built mine with the exception of no volume pot and I have no signal. what can I do?
Hi Guys,
i've build the BoobTube Twin from Juansolo with the Charge Pump from Renegadrian. Here are the schematics:
(http://juansolo.demon.co.uk/stompage/schematics/Valve%20Casters/BoobTubeTwin.jpg)
(http://juansolo.demon.co.uk/stompage/schematics/Misc/666SBB.jpg)
It's not running very well, Tone Knobs and the Master Volume are working great but if i turn the gain knob, i only get a weird buzzing noise.
Here are my results:
(http://i47.tinypic.com/w1751k.png)
(http://i49.tinypic.com/wio5mx.jpg)
Thanks,
Jan
well off hand I'd ssay something is wrong when you have that kinda voltage on pin 7 of tube 2.
Look I don't know what the dude who drew up the boobtube is thinking, not in an insulting way as I honestly don't know everything about these designs... but from what I know you should be drawing you out sig from ether pin 6 or 2 then through a cap and out to the tone stack or volume.
I only understand some of what is going on with V2B's pin 8... but what I do know is that you may want to try adding a cap(10nf to 1uf) between vb2's Pin 7 and va2's Pin 2.
Yeah, I believe Ark Angel HFB is right... I think you need another 100k resistor from the power rail to pin 6 of V2B. In between the 100k resistor and pin 6 connect to the 33k and 470pF cap of the tone stack. You also may want to replace the 100k resistor from pin 8 of V2B to ground to 820 ohm or so..? Maybe a 22n cap from pin 6 on V2B to the tone stack?
btw way guys... has anyone tried much lower value for the plate resistors?
I've been having some really lovely crunch tones from about 22k to 33k.
I'm making one for a buddy of mine and with the profit from selling it I'll be sure to grab some more jumpers(I don't like bread boards...) and will fully jumper a tube socket up so that I can test every component.
I'll try drawing signal from the pin 3/8 side but I've only every seen that on this last boobtube design so it may be a mistake.
also I think if we pay some careful attention to the bass in the circuit, there may be a way to get true high gain out of one tube without it sounding flabby... I'm if we limit bass and tweak the values for cathode resistance and plate resistance we might just get a really great hard od pedal that could be used as some kinda awesome crunch pedal and then a solo booster.
I still have not tried the double version but I'll pick up some larger cases and have a go at it. ^_^
If you're wanting a higher-gain pedal, check out the Tube Star...
IDK man two valve caster into each other is a crazy great gain pedal.
That Boob Tube twin schematic looks like a Marshall 2204 preamp, the V2b is a DC-coupled cathode follower therefore the high voltage on pin 7. There is nothing wrong with it that I can see.
so you can draw signal from the pin 8/3 side of triodes... learning new crap all the time. XD
Yes its similar in principle to the tranny emitter-follower, it doesn't boost voltage (there is no voltage gain), but it can drive a bigger load (lower output impedance). In that schem they are using it to drive the tone stack.
The more I learn the less I know, these forums are good at doing that to a person :)
Quote from: Ronan on December 07, 2012, 06:02:37 AM
Yes its similar in principle to the tranny emitter-follower, it doesn't boost voltage (there is no voltage gain), but it can drive a bigger load (lower output impedance). In that schem they are using it to drive the tone stack.
The more I learn the less I know, these forums are good at doing that to a person :)
lol I know... it like you learn something and you are like ok these are the guide lines... then the learn a little more and all your guide lines fall completely away are "Not always true."
So basically the last bit in the boobtube is like a buffer too drive the tone stack and lower the impedance so that pedal that come after it are not crap sounding.
Quote from: Ronan on December 07, 2012, 04:48:02 AM
That Boob Tube twin schematic looks like a Marshall 2204 preamp, the V2b is a DC-coupled cathode follower therefore the high voltage on pin 7. There is nothing wrong with it that I can see.
Yup. All it is is the pre-section of a JCM800 with a little bit of filtering on the end of it to tame the top a little that dealt with by the presence control later in the amp.
Not sure what's up with the OPs build.
Quote from: fastcar123 on December 01, 2012, 06:07:30 PM
I built mine with the exception of no volume pot and I have no signal. what can I do?
From the negative side of the 1uf output capacitor, where your output is connected, place a 100k resistor to ground. This will work as if you've cranked your 100k Volume pot to max. That should give you an output signal
Quote from: esdiezy28 on December 09, 2012, 07:42:46 PM
Quote from: fastcar123 on December 01, 2012, 06:07:30 PM
I built mine with the exception of no volume pot and I have no signal. what can I do?
From the negative side of the 1uf output capacitor, where your output is connected, place a 100k resistor to ground. This will work as if you've cranked your 100k Volume pot to max. That should give you an output signal
I'm probably showing a startling amount of noob-ishness but as to your statement above... WHHHYYY?
No really... wy would the resistor give him an output signal?
is it an impedance issue. (Still barely grasp anything about impedance at all btw.)
I just tossed the pull-down resistor in there to simulate a volume pot. I'm not exactly sure why that is. This page here has some great equations http://www.aikenamps.com/Equations.htm (http://www.aikenamps.com/Equations.htm).
I see the resistor plays a part in output impedance. It sets the load resistance, or the input resistance of the following stage (for me, thats right into my amp). Though the output impedance (Z) is = to the plate resistor if RL is not added. Also, the plate resistor (RP), output capacitor, and load resistor form a high pass break point. Why this is keeping you from getting an output signal without the load resistance, I'm not sure
Trying to troubleshoot my valvecaster. I am getting a lot of gain and the volume and tone pots don't seem to do anything. I have checked the wiring a million times but can't see a problem, why might I be getting these results?
Quote from: Alfie on January 03, 2013, 01:06:33 PM
Trying to troubleshoot my valvecaster. I am getting a lot of gain and the volume and tone pots don't seem to do anything. I have checked the wiring a million times but can't see a problem, why might I be getting these results?
probably not grounded those two pots. which wiring diagram did you use? the pcbless layout at beavis is a bit odd as it's different to their schematic. but there's a wire from both pots to sleeve, with a cap, C4, from the tone one, which is in a different place in the schematic.
Hello all
I just want to thank everybody! This has been,and still is the best thread I've read(many times).
I've built valvecasters of all types, built them into ss amps, with great results.
Now I'm going to try the buffered/bootstrapped, going to try my own variation.
Just wanted to thank all for some great info.
Steve 6BQ5
Hi! I've just built a valvecaster, but have a few doubts about using a voltage regulator.
If I want to use a 12v wallwart, and a 7809 regulator, how should I wire it?
12v to the heaters, unregulated directly from the ww and 9v to the rest of the parts, from the regulator?
I'm guessing that the heaters aren't sensible to the noise from the ww, am I wrong?
Could I use a 18v ww with a 7812?
btw: I've already done some changes to it, removed the tone and increased r2 to 220k in order to increase output volume.
Thanks!
if your wall wart gives out 12V stabilized regulated and filtered, you're lucky! you don't have to use a regulator at all.
just feed both the heaters and the plates with that voltage.
Valvecasters need a good regulated power supply - just try it!
What he said^; however if your wall wart is unregulated, you could have more than 12v on the heaters and damage them. If that's the case, it would be best to your the 18v supply and a 12v regulator (with filter) for the heaters and the rest of the circuit. You'll probably get more headroom doing that anyway.
Quote from: Alfie on January 03, 2013, 01:06:33 PM
Trying to troubleshoot my valvecaster. I am getting a lot of gain and the volume and tone pots don't seem to do anything. I have checked the wiring a million times but can't see a problem, why might I be getting these results?
You foul'd something up... I'd say give us some voltage readings and see what comes of it.
The output volume of my valvecaster seems to be lower than what I expected...
When I set the volume to max, and the gain to minimum, I get an output that in only as loud as the bypassed signal.
Is this it's normal behavior? I thought the output was supposed to be stronger as this circuit is used almost as is booster purposes (see the tube town banana booster)
If I want to make the signal stronger than the one coming from the guitar I have to use a higher gain value, but then my signal get's a bit overdriven... (as expected).
And this is with the tone cap+pot removed...
running JJ 12au7, regulated 12v supply, and a strat with singles and humbuckers.
Thanks! :)
i use a wall wart for heaters when i breadboard tubes. i just measure the voltage under load and add a resistor or diode if necessary. i haven't had any noise, but if you go over to diyaudio, they'll all talk of diode switching noise and the like. my wall wart is probably a smps.
New builder decloaking off the starboard bow.....
Santa brought me some 12AU7 valves and a 3PDT switch, so I built me a valvecaster as my first ever build - Is is normal to be so stoked when a build works?? I'd have posted earlier, but I've been goosing the front end of a Marshall class5 with it and that's taken all my time over the last week.... And I have read all 150 odd pages of this thread...learned a heck of a lot about tube circuits.
I'd like to say it worked first time, but it took a reflow of a duff connection on the tube socket to get it to work. Built on breadboard as I'm waiting for some perfboard to arrive. No tone control, 9V is ok, but 12V is definitely better. Its loud :icon_biggrin: 100uf electrolytic capacitor across + and - rails of the regulated 12V PS seems to make it a lot quieter.
Its a bit farty in the bottom end, changing C1 to 22nf helps a bit, but it sounds a bit like a solid state amp overdriving....Its fine for low levels of boost, and pretty creamy in the mid range with a Les Paul.
However, I didn't like the low end (and for some reason couldn't get a twincaster to work), so I dug into my tube amp book (vol4) and built something else a bit more to my taste .... (see JCM-caster thread ;D ).
Congratulations and welcome!!! It's an endorphin rush when you build one and it works! Be careful because it's addicting! Just don't forget to play your guitar and say hi to the family now and then. :)
Family? Who they??
Am I a bad person from sitting on some value changes that turn this into the best pedal I've ever played...
No really I've tested probably 60 different combinations of values.... systematically and recorded the results.
I won't let exactly what I'm doing slip but I'm telling you all there is crunchy gold to be found here.
Let me suggest the following... STRONGLY SUGGEST!!!
1. Built the valvemaster...
2. R2/R3: (Lower values are better for me... think on it like this, if you keep the gain lower in each stage, the end result is still a lot of volume bit it is neat.)
3. R4/R5: (higher values may be better)
4. C4/C5: (High values worked better)
Lastly add a an EQ circuit just before the volume control... a passive one works fine. I've posted a good one in the past...
I did what one of the users suggested, I forget whom, and raised the value of R1 to 2M. Could this have ruined the tube? After I changed this, there was no sound whatsoever, even after i changed the resistor back to 1M. Please help
Think you may have a problem somewhere else... but when in doubt take some voltage reading for us.
I've tried higher values than that without hurting the tube so... idk.
Yes, I figured it out, it turns out my gain knob is messed and i just couldn't hear it due to the hideously low gain. I just jumpered over it for now to have maximum gain. Ill have one order a new knob soon.
I have another question though, how do I make it louder? it is noticably quiter than when the pedal is turned off. Surely it is just as simple as changing a resistor. I tried increasing the resistance from both grids to ground and that helped a little bit, now when it's on it is about 95% of the volume when the pedal is off. Could this have anything to do with me having EMG active pickups?
Thanks in advance.
Yes, I figured it out, it turns out my gain knob is messed and i just couldn't hear it due to the hideously low gain. I just jumpered over it for now to have maximum gain. Ill have one order a new knob soon.
I have another question though, how do I make it louder? it is noticably quiter than when the pedal is turned off. Surely it is just as simple as changing a resistor. I tried increasing the resistance from both grids to ground and that helped a little bit, now when it's on it is about 95% of the volume when the pedal is off. Could this have anything to do with me having EMG active pickups?
Thanks in advance.
Quote from: josh1324 on January 26, 2013, 09:01:39 AM
Yes, I figured it out, it turns out my gain knob is messed and i just couldn't hear it due to the hideously low gain. I just jumpered over it for now to have maximum gain. Ill have one order a new knob soon.
I have another question though, how do I make it louder? it is noticably quiter than when the pedal is turned off. Surely it is just as simple as changing a resistor. I tried increasing the resistance from both grids to ground and that helped a little bit, now when it's on it is about 95% of the volume when the pedal is off. Could this have anything to do with me having EMG active pickups?
Thanks in advance.
voltage reading bro...
Ground the black lead of your multi-meter and then touch the red lead to each pin of the tube while it is plunged in and turned on...
Also try a value of 22k for R2/R3... This pedal should give you close to 40db of boost... so if it is less than unity you got some real weirdness going on.
Okay, voltage reading with black lead connected to -9 volts:
Pin 1: 8.99v
Pin 2: -0.2v
Pin 3: 0v
Pin 4: 0v
Pin 5: 9.23v
Pin 6: 8.86v
Pin 7: -0.2v
Pin 8: -0.3v
Pin 9: 0v
Or was I supposed to connect the black to an actual ground like the third prong on a plug?
Quote from: josh1324 on January 26, 2013, 01:29:48 PM
Okay, voltage reading with black lead connected to -9 volts:
Pin 1: 8.99v
Pin 2: -0.2v
Pin 3: 0v
Pin 4: 0v
Pin 5: 9.23v
Pin 6: 8.86v
Pin 7: -0.2v
Pin 8: -0.3v
Pin 9: 0v
Or was I supposed to connect the black to an actual ground like the third prong on a plug?
Interesting... those seem right... ok first... Can you list the values of everything you used.
The next step in trouble shooting would be to audio prob. Take off one of your multi meter leads and jump the base of it to the tip of a guitar cable that is plugged into your amp. make sure another clip also goes from the sleeve to ground in the circuit.
Turn everything on and plug a guitar into the effect. leave the guitar in a stand btw. Turn on your amp. Strum the guitar before every prob.
Now take the other end of the muilt-meter lead and touch these places in the circuit, turn all pots all the way up. Record what sound is there...
1. The tip of the input cable (Should be the normal sound of the guitar as this bypasses the effect.)
2. Pin 2 (Should be mostly the same.)
3. Lug one, of the gain pot. (Should be very loud, if it is not loud move to Pin two and test there.)
4. Pin 7. (Should be as loud as before the gain pot... if it isn't turn the pot the other way and retest. if still not loud but before the pot is loud, then suspect bad pot.)
5. Pin 6. (Should be crazy loud.)
6. Before and after the tone circuit.
7. Before and after the Volume pot.
If you do the above it will allow us to pin point the area of the pedal that has the problem... good luck
By record, do you mean literally record it? Or just jot down roughly how loud it is?
Also, sorry for the late reply, I have exams right now and I'm really busy lately.
Here are the values:
R1 1M
R2 22K
R3 22K
R4 470K
C1 47nF
C2 47nF
C3 1uF (electrolytic)
C4 10nF
VR1 B50K
VR2 A100K
VR3 A100K
The tube is the 12au7 by JJ Eletronic.
The input voltage is ~9,23v
Okay, I tested all of the things through an amp, here are the results:
Tip of input cable: normal
Pin 2: Normal
Lug 1 and 2 of gain pot: No sound whatsoever (I stated earlier that this pot is broken, so i tested it with the pot bypassed all together, and with pin 3 of the tube left unconnected.)
Pin 7: No guitar sound, but a weird constant tone
Pin 6: Quieter than just bypassing the effect
Before and after tone circuit: Quieter than bypassing the effect (I realized later that the tone isn't grounded, the connection broke, but i don't think this would change anything.)
Before and after the volume pot: Quieter than bypassing the effect.
Quote from: josh1324 on January 29, 2013, 10:10:49 AM
By record, do you mean literally record it? Or just jot down roughly how loud it is?
poor choice of words, sry. Just take notes... you'd be surprised how after you try five or six things... you can't really remember what that first thing sounded link.
hi guys.
I didnt wanted to open a new post for that cause probably it's something simple.
I use the valve for my synths.
The problem is that the gain is still hearible when turning the gain pot fully CCW.
Any Ideas on how to make the gain begone?
I build with the original specs, no mods and no tone.
Cheers,
Isak E.
Drop R2/R3 to 10k makes it a pretty nice booster for me... a lot of clean raw db boost.
״Drop R2/R3 to 10k makes it a pretty nice booster for me... a lot of clean raw db boost״
Sorry for asking, dose it refere my post?
If I reduce r2 and r3 will it make the gain begone?
Quote from: Isak on January 30, 2013, 07:41:30 AM
״Drop R2/R3 to 10k makes it a pretty nice booster for me... a lot of clean raw db boost״
Sorry for asking, dose it refere my post?
If I reduce r2 and r3 will it make the gain begone?
Try it and see...
I'll try that today, thank you :)
Quote from: josh1324 on January 29, 2013, 11:01:31 AM
Okay, I tested all of the things through an amp, here are the results:
Tip of input cable: normal
Pin 2: Normal
Lug 1 and 2 of gain pot: No sound whatsoever (I stated earlier that this pot is broken, so i tested it with the pot bypassed all together, and with pin 3 of the tube left unconnected.)
Pin 7: No guitar sound, but a weird constant tone
Pin 6: Quieter than just bypassing the effect
Before and after tone circuit: Quieter than bypassing the effect (I realized later that the tone isn't grounded, the connection broke, but i don't think this would change anything.)
Before and after the volume pot: Quieter than bypassing the effect.
Ark Angel, what do you suppose might be wrong with my pedal?
Quote from: josh1324 on January 30, 2013, 03:22:20 PM
Quote from: josh1324 on January 29, 2013, 11:01:31 AM
Okay, I tested all of the things through an amp, here are the results:
Tip of input cable: normal
Pin 2: Normal
Lug 1 and 2 of gain pot: No sound whatsoever (I stated earlier that this pot is broken, so i tested it with the pot bypassed all together, and with pin 3 of the tube left unconnected.)
Pin 7: No guitar sound, but a weird constant tone
Pin 6: Quieter than just bypassing the effect
Before and after tone circuit: Quieter than bypassing the effect (I realized later that the tone isn't grounded, the connection broke, but i don't think this would change anything.)
Before and after the volume pot: Quieter than bypassing the effect.
Ark Angel, what do you suppose might be wrong with my pedal?
sorry I missed your post.. ok... ok... (you are using the valve master or the valve caster.) I think you may be using the valvecaster which is fine, but means me having you audio prob at the gain pot was a waste and I still need you to audio probe both sides of the cap that comes off pin 1.
Ok well here are a few things...
1.
(This only applies if you used the valvemaster.) Lug 1 of the gain pot is the signal before the gain pot. If you are not getting good sound there... then there is a problem before that gain pot...
the following should be helpful to both the valve caster and valve master.2. In line with the above I seriously think your problem are your Cathodes. In the valve caster the gain pot works as a variable cathode resistor. In both versions
Increasing the Cathode resistance drops the volume of the pedal... I have mine right now around 10k but will be testing a few changes to lower the value.
3. It does mater that your tone is not grounded... without being grounded there is no were for the signal to bleed to meaning the tone control won't work.
DO THE FOLLOWINGBypass whatever you have coming off pin 3 and pin 8, and connect both to ground. (Test the pedal afterwards. Also check for sound at Pin 1 of the tube.)
2. If the above doesn't work test with another tube.
3. If that doesn't work... >_> well I'd suggest removing the tube and considering gas to start the fire but we can keep trying other things.
Hi Ark Angel HFB,
that is much much much better!!!
thank you for that.
i can still hear the drive but much lower, its only heritable when rising the resonance of the filter.
i guess this is as low as it can get right?
Quote from: Isak on January 30, 2013, 06:31:39 PM
Hi Ark Angel HFB,
that is much much much better!!!
thank you for that.
i can still hear the drive but much lower, its only heritable when rising the resonance of the filter.
i guess this is as low as it can get right?
You could try a lower value... 5k even 1k... it won't hurt to try... for me between 10k and 33k were what I like for guitar. You only get distortion when you hit the stings hard so you get this great ability to change your sound by just playing softer or harder.
[quote author=Ark Angel HFB link=topic=63479.msg892306#msg892306 date=13
sorry I missed your post.. ok... ok... (you are using the valve master or the valve caster.) I think you may be using the valvecaster which is fine, but means me having you audio prob at the gain pot was a waste and I still need you to audio probe both sides of the cap that comes off pin 1.
Ok well here are a few things...
1. (This only applies if you used the valvemaster.) Lug 1 of the gain pot is the signal before the gain pot. If you are not getting good sound there... then there is a problem before that gain pot...
the following should be helpful to both the valve caster and valve master.
2. In line with the above I seriously think your problem are your Cathodes. In the valve caster the gain pot works as a variable cathode resistor. In both versions Increasing the Cathode resistance drops the volume of the pedal... I have mine right now around 10k but will be testing a few changes to lower the value.
3. It does mater that your tone is not grounded... without being grounded there is no were for the signal to bleed to meaning the tone control won't work.
DO THE FOLLOWING
Bypass whatever you have coming off pin 3 and pin 8, and connect both to ground. (Test the pedal afterwards. Also check for sound at Pin 1 of the tube.)
2. If the above doesn't work test with another tube.
3. If that doesn't work... >_> well I'd suggest removing the tube and considering gas to start the fire but we can keep trying other things.
[/quote]
I will try to get those results to you asap, but it is the valve caster, not master. Do you mind me asking what the difference is between the two?
I will try to get those results to you asap, but it is the valve caster, not master. Do you mind me asking what the difference is between the two?
[/quote]
More or less it is the same... some things are changed around like a pot is add in between the two stage and acts as a gain pot. the old gain pot becomes a constant resistor.
Quote from: Ark Angel HFB on January 30, 2013, 05:26:54 PM
sorry I missed your post.. ok... ok... (you are using the valve master or the valve caster.) I think you may be using the valvecaster which is fine, but means me having you audio prob at the gain pot was a waste and I still need you to audio probe both sides of the cap that comes off pin 1.
Ok well here are a few things...
1. (This only applies if you used the valvemaster.) Lug 1 of the gain pot is the signal before the gain pot. If you are not getting good sound there... then there is a problem before that gain pot...
the following should be helpful to both the valve caster and valve master.
2. In line with the above I seriously think your problem are your Cathodes. In the valve caster the gain pot works as a variable cathode resistor. In both versions Increasing the Cathode resistance drops the volume of the pedal... I have mine right now around 10k but will be testing a few changes to lower the value.
3. It does mater that your tone is not grounded... without being grounded there is no were for the signal to bleed to meaning the tone control won't work.
DO THE FOLLOWING
Bypass whatever you have coming off pin 3 and pin 8, and connect both to ground. (Test the pedal afterwards. Also check for sound at Pin 1 of the tube.)
2. If the above doesn't work test with another tube.
3. If that doesn't work... >_> well I'd suggest removing the tube and considering gas to start the fire but we can keep trying other things.
Okay, both sides of C2 (the capacitor coming from pin 1) have sound going through them, but they are extremely quiet. I think I
may have found my problem though, the volume level before C1 is equal to the volume of bypassing the entire effect. However, before my true bypass switching circuit (where i would plug in the input and output of the effect) is much quieter. here is the schematics I used for that: http://www.beavisaudio.com/projects/Looper-Switcher/True-Bypass-Looper-With-LED.png . Do you see anything wrong with that? Or do you think it's just how i hooked it up?
Quote from: josh1324 on February 01, 2013, 01:10:42 PM
Quote from: Ark Angel HFB on January 30, 2013, 05:26:54 PM
sorry I missed your post.. ok... ok... (you are using the valve master or the valve caster.) I think you may be using the valvecaster which is fine, but means me having you audio prob at the gain pot was a waste and I still need you to audio probe both sides of the cap that comes off pin 1.
Ok well here are a few things...
1. (This only applies if you used the valvemaster.) Lug 1 of the gain pot is the signal before the gain pot. If you are not getting good sound there... then there is a problem before that gain pot...
the following should be helpful to both the valve caster and valve master.
2. In line with the above I seriously think your problem are your Cathodes. In the valve caster the gain pot works as a variable cathode resistor. In both versions Increasing the Cathode resistance drops the volume of the pedal... I have mine right now around 10k but will be testing a few changes to lower the value.
3. It does mater that your tone is not grounded... without being grounded there is no were for the signal to bleed to meaning the tone control won't work.
DO THE FOLLOWING
Bypass whatever you have coming off pin 3 and pin 8, and connect both to ground. (Test the pedal afterwards. Also check for sound at Pin 1 of the tube.)
2. If the above doesn't work test with another tube.
3. If that doesn't work... >_> well I'd suggest removing the tube and considering gas to start the fire but we can keep trying other things.
Okay, both sides of C2 (the capacitor coming from pin 1) have sound going through them, but they are extremely quiet. I think I may have found my problem though, the volume level before C1 is equal to the volume of bypassing the entire effect. However, before my true bypass switching circuit (where i would plug in the input and output of the effect) is much quieter. here is the schematics I used for that: http://www.beavisaudio.com/projects/Looper-Switcher/True-Bypass-Looper-With-LED.png . Do you see anything wrong with that? Or do you think it's just how i hooked it up?
no I don't see anything wrong... but you should be getting more volume than barely unity from the first section... I'd suggest by passing your gain pot with some jumpers and test from there...
also make sure pin 8 is connected to ground.
My gain pot is jumpered to ground, the pot isn't working :( . And I double checked that my pin 8 was grounded when I was looking at the two cathodes
Quote from: josh1324 on February 02, 2013, 08:26:23 AM
My gain pot is jumpered to ground, the pot isn't working :( . And I double checked that my pin 8 was grounded when I was looking at the two cathodes
So barely unity after the first section... then above unity at pin 7...
Have you tried a different tube?
I haven't gotten around to it yet, I don't have another tube :/ is there any name brands of tubes you would suggest?
Quote from: josh1324 on February 02, 2013, 09:56:24 AM
I haven't gotten around to it yet, I don't have another tube :/ is there any name brands of tubes you would suggest?
well i put JJ's in my amps but since you already have one of those... idk... maybe find something from ebay for cheap?
Also don't be afriad of starting over if things don't work... sometimes the best thing to do is just rebuild it.
not to jump in or take over, but do you have a voltagemeter or a oscope?
If you have a voltagemeter can you set it to AC, and measure the signal going to the grids and them measure the voltage after the coupling capacitors? normally when you are getting no gain or not a lot, its because you have something going to ground in the signal chain. Pin 3 and 8 set the voltage the grid will conduct at, so setting it to ground will make it always conduct, which is good for trouble shooting. at 9 - 12v you may get current on your grid so sometimes adding the coupling cap at the input will clean up issue with that, mostly noisy pots on the guitar
The brand of tube does not matter that much in my opinion ( I know sacrilege.. ), at least when it comes to just working, some will sound different, even in the same brand. but any brand 12au7 should work. They are very close to the 12u7 which was made for 9 - 12 volts so they work well in this design. Hope this can help
Hi there.
does any one can say what will be the max V input to the pedal? 5V..7V...10V pp?
I'm asking cause I built a filter effect and found that If the output of the filter is high and connect it to the pedal the pedal is killing the sound.
It sounds very choked and with low output, rather then that... The pedal killes the reso of the filter, only if I take the reso all the way CW to self osc mode you can hear the reso.
If I turn the input pot of the filter down to 9 o'clock only then the pedal sounds good even amazing I must say, crunchi sound which I love very much.
But...(there always a but) if the input is low then the output will be low as well.
my thinking was that Ill put a resistor or trimmer at the input of the pedal and at the output of the pedal put an amp to amplifi the signal back to the same vol of the filter.
what do you say? Is it a good idea?
If yes, Can you please advice me for simple amp scheme to boost the signal?
BTW this is my effect,
MFOS SVF
MFOS NOISE
MFOS LFO
MFOS AR
MFOS SIGNAL TO GATE
BUGCRUSHER
AND VALVECASTER OVERDRIVE :)
(http://i1234.photobucket.com/albums/ff408/Isakeliyahu/0DED47D0-7C4E-4B90-BF81-B9D5B5D670A1-410-00000110346C1324.jpg)
Thanks in advance for the help.
@ Isak- I absolutely love that setup you have for mounting. I wish I could clearly label my pedals in such a way, usually just get a perm marker and write a couple times over :P
Thank you very much for your kind words :)
I made the design on adobe illustrator and went to a local shop that print on aluminum, it's cheap here so why wouldn't I do that?
I Gusse that for pedals it's not good but for desktop effect it's great :)
Quote from: Isak on February 14, 2013, 11:21:25 AM
Hi there.
does any one can say what will be the max V input to the pedal? 5V..7V...10V pp?
I'm asking cause I built a filter effect and found that If the output of the filter is high and connect it to the pedal the pedal is killing the sound.
It sounds very choked and with low output, rather then that... The pedal killes the reso of the filter, only if I take the reso all the way CW to self osc mode you can hear the reso.
If I turn the input pot of the filter down to 9 o'clock only then the pedal sounds good even amazing I must say, crunchi sound which I love very much.
But...(there always a but) if the input is low then the output will be low as well.
my thinking was that Ill put a resistor or trimmer at the input of the pedal and at the output of the pedal put an amp to amplifi the signal back to the same vol of the filter.
what do you say? Is it a good idea?
If yes, Can you please advice me for simple amp scheme to boost the signal?
BTW this is my effect,
MFOS SVF
MFOS NOISE
MFOS LFO
MFOS AR
MFOS SIGNAL TO GATE
BUGCRUSHER
AND VALVECASTER OVERDRIVE :)
(http://i1234.photobucket.com/albums/ff408/Isakeliyahu/0DED47D0-7C4E-4B90-BF81-B9D5B5D670A1-410-00000110346C1324.jpg)
Thanks in advance for the help.
With low voltage on the tube, I would not push more than 4v and expect anything clean, and that is dependent on your cathode resistor size on your input. your max swing can only be your high voltage. This design is a boost, so I would put it first in your. Its also low impedance compared to the rest of your devices, which may cause issues.
where in the effect chain are you looking to add a booster at? I can think of several simple options. FET Buffer to a BJT Linear boost, level controlled with a audio pot.
Thanks for replying guys.
I figure it would be less the 5V input cause the filter can handle up to 5V, if its sound choked after the overdrive the it's make sence.
My chain is filter ---> overdrive with on/off switch.
I was thinking to add an input pot/trimmer to the overdrive and at the output of the overdrive to add a boost circuit to the signal back to 5V.
Hope it makes sence.
Cheers.
BTW I'm running the whole deal with 12V
QuoteWith low voltage on the tube, I would not push more than 4v and expect anything clean, and that is dependent on your cathode resistor size on your input. your max swing can only be your high voltage. This design is a boost, so I would put it first in your. Its also low impedance compared to the rest of your devices, which may cause issues.
sorry for the newbi question..
By saying cathode resistor did you mean the 50k pot?
I think I can fix the low impadance issue by using a buffer, I could be wrong tho...
I'll buffer it before going to the overdrive by using the advice of the next site..
http://www.eecs.tufts.edu/~dsculley/tutorial/opamps/opamps5.html
If I understand correctly the signal will go through the opamp buffer and the output from the opamp buffer will be a Celt low impadance so that should fix things, right?
stick a buffer from your output to filter input. Vbias with a 1M5 resistor from your 12V+, coupled with a 1M resistor to ground. The 1M5 resistor should drop 7.2V, leaving you 4.8V (very close to the 5V your looking for).
I wonder if the valvecaster would be good in front of a modeler, reduced gain of course, to warm up the sound of amp models ??
Dear all,
Thank you for the contributors to this thread - it's great stuff, and has led me to make the following decisions:
I'm going to make a Valvemaster based on the Frequency Central schematic at http://www.diystompboxes.com/smfforum/index.php?topic=63479.msg819365#msg819365.
I'm going to use the pictorial guide by David Smith (https://picasaweb.google.com/lh/photo/nWmym5pZuB0fEC5P-SPpkQ) to help with the wiring, substituting the valvemaster components where necessary (I'm new to a lot of this stuff, and this picture will help me to interpret the circuits).
I'm going to use http://gaussmarkov.net/wordpress/thoughts/wiring-up-a-1590b/ to help me wire up the 3PDT switch, and http://www.instructables.com/id/Choosing-The-Resistor-To-Use-With-LEDs/ . (I'm sticking all this in, in case it helps other newbies).
I've got quite a few of the components knocking about from old amps, and an old, broken, wah-wah pedal box to use as a (spacious!) enclosure.
I have a budget guitar and SS amp that I am reasonably happy with (solid bodied Yammy Pacifica and H&K Edition Blue 60R), a limited budget, but a hankering after some tube sounds - plus I want a go at making something so cool!
I'm about to start ordering the stuff I haven't got, but before I do, can I ask the esteemed contributors to this forum the following questions:
1. I'd like to learn about what I'm making - is there anywhere you'd recommend to look at the theory behind what's happening in this valve pre-amp circuit. I've spent a lot of time reading this thread, but I would be lying if I said I'd read every page and that I understood it all, and this will be my first project like this since I made a crystal set circa 1980. On the other hand, I'm reasonably intelligent, fine with a soldering iron, and have a multimeter at the ready!
2. For which components are the values really critical, and which just need to be there or thereabouts?
3. Any last pieces of advice?
Thank you!
Quote from: valve999 on February 25, 2013, 03:42:50 PM
1. I'd like to learn about what I'm making - is there anywhere you'd recommend to look at the theory behind what's happening in this valve pre-amp circuit.
Valve Wizard is a mandatory site to visit!
Then just study fenders and marshalls, it's a great beginning!
Basically the valve master follows your ordinary tube preamp stage.
Thanks, Renegadrian - heading over there now.
Hey guys, been trawling though the tread looking for PCB artwork for the ValveCaster, but couldn't find one?
Have you ever heard of a thing called google'? :icon_lol:
+1. Like a candy store. ;)
https://www.google.com/search?q=valvecaster+pcb&hl=en&client=safari&tbm=isch&tbo=u&source=univ&sa=X&ei=0nI7UY7nM-e32wXWsoAw&ved=0CC4QsAQ&biw=480&bih=268
Quote from: Renegadrian on March 09, 2013, 11:58:15 AM
Have you ever heard of a thing called google'? :icon_lol:
Quote from: Jdansti on March 09, 2013, 12:37:27 PM
+1. Like a candy store. ;)
OK, I kind of asked for that! :icon_wink:
But ignoring the fact "Have you ever heard of a thing called google?" could be applied to 99% of questions posted here, or on any forum!
I was being a little more community focused, and wondering if anyone here had contributed a PCB that had been verified, or tweak with options and documentation. Rather then just grabbing a random layout off google image only to find out there was something better designed or supported within the pages of this thread.
From the forum:
Quote from: rotylee on December 29, 2011, 12:40:40 PM
a manual of condensed thread
http://www.aronnelson.com/DIYFiles/up/12AU7-6111_Valve_Caster_Summary_Rev002.pdf
check HUM and NOISE
a bread board layout of original circuit
http://www.beavisaudio.com/bboard/projects/ttb_Valvecaster.pdf
tube cricket
http://www.diystompboxes.com/smfforum/index.php?topic=63479.msg506164#msg506164
boobtube schem
http://juansolo.demon.co.uk/stompage/schematics/Valve%20Casters/BoobTubeSchematicV2.jpg
latest iteration the Valve-master:
http://www.diystompboxes.com/smfforum/index.php?topic=63479.msg819365#msg819365
high voltage
http://www.geofex.com/circuits/+9_to_33.htm
charge pump layout
http://www.diystompboxes.com/smfforum/index.php?topic=71381.msg607779#msg607779
The first link above has several layout options, including PCB. I think that most people just do a point to point build, but maybe someone who's done a PCB with chime in.
hi
i built 9v valve overdrive like there is on beavis audio. (http://www.beavisaudio.com/projects/ValveCaster/MatsuminValveCaster.gif) but output si sooo low, sometimes even nothing when im moving my gear in winter. can you give me advice please? i cannot find here anyone with same problem like i have (sory, i cannot read all pages of this discussion wire, its so long). thx very much for anything
kivi
God I hope this thread isn't dead yet because I REALY need your help... So I built a doublecaster with 2 12AX7s. Yea, I know 12ax7s are generally frowned upon when it comes to valvecasters but they completely work for me. :) Kept the circuit pretty standard, only changed a few resistor values. 12,6V for the heaters, 18V for the rest. Now... Here's the catch: When I wire 3 9V batteries in series and run the doublecaster of those, I get a (at least to my ears) HEAVENLY sound. Crunchy crunch tones, saturated drive tones and next to no hum... But ofcourse, with two tubes those batteries wouldn't last 15minutes... So I hooked the circuit up to a 24V trafo through two LM317s (One for 12,6V the other for 18V) with tons of filtering... When I say tons I mean 4 1000µF capacitors infront of the regulators and 2 1000µF capacitors after EACH of the regulators. And i threw in a few smaller value ones for good measure. Hell, I even put a .65µF 250V capacitor I had lying around infront of the trafo... And after all that filtering I STILL get unacceptable amounts of hum! Adding capacitors doesn't seem to help, however removing them adds more hum. Removing just half of the capacitors would make the circuit pretty much useless... So my question is: How do I get rid of the hum? Seeing as how the circuit works perfectly with batteries, the problem must be with the power supply... Even though I filtered the living heck out of it, it seems I've forgotten something... :S
Any help would be greatly appreciated!
Thanks in advance!
Siroky, Could maybe be a bad tube or something in your circuit is bridged or maybe a stuck pot value. take pics and look at the debug thread.
http://www.diystompboxes.com/smfforum/index.php?topic=29816.0
Also all of these valvecaster variants work better at 12v's for the heaters and higher for the rest of the circuit.
If your running off a 9volt battery it will eat the battery fast and once its drained to a certain point it just wont have enough amps for the heaters which is something around 400ma.
Also For toplak whats the amps rating on your power supply ? If you don't supply enough current with these tubes they hum, just gonna guess that 2 tubes and the rest of the circuit and any voltage regulators are gonna be hungry for amps and I would suggest something over 1 amp maybe 2 amps would work best .
If you read back a few pages in this thread there's a lot of info about hum and different causes when using switching mode power supplies and voltage regulators. There's also grounding issues to look at and is it inside an enclosure for shielding.
Good luck guys and welcome to the forum :)
Also reading this entire thread is good for you, think of it as a right of passage ! Can really learn a lot from such a wonderfully large thread with lots of great info threads like these don't come along every day.
Thanks for your help mustachio. My trafo is rated at arround 1,1A. I've measured the amp draw with the trafo and the batteries and with both I got a consistant 0.33A so I doubt amperage is a problem... If I had a higher rated power supply handy I would try it but I don't think I have one at the moment... I'll try to find the part about the hum you mentioned. I already skimmed through all the pages... Guess I must have missed that part. :S
In the mean time, any more advice? :) It seems filtering is the main issue. Any advanced filtering circuits I don't know of?
Welcome! :)
Good info from Jim.
In your earlier thread, you said two things that caught my attention:
1) works great on 3- 9V batteries
2) power supply = transformer to regulators with filtering on both sides of the regulators.
You've probably got enough filtering on the power supply, but you didn't mention a rectifier. Do you have one between the transformer and regulators to convert AC to DC, or is the transformer output ready rectified?
Quote from: Jdansti on March 20, 2013, 09:27:13 PM
Welcome! :)
Good info from Jim.
In your earlier thread, you said two things that caught my attention:
1) works great on 3- 9V batteries
2) power supply = transformer to regulators with filtering on both sides of the regulators.
You've probably got enough filtering on the power supply, but you didn't mention a rectifier. Do you have one between the transformer and regulators to convert AC to DC, or is the transformer output ready rectified?
Indeed I do have a rectifier. :) I'll have some pictures and maybe a schematic up by the end of the day.
Thanks for the help!
It's been a while since I checked in here.
Did we break any new ground recently?
I'm thinking of doing some starved plate CLEAN preamp designs.
Is anyone using their Valvecaster for cleans?
hello,
i found this http://www.diystompboxes.com/smfforum/index.php?topic=77190.0
didnt build it yet.
hope this helps in some way.
cheers.
It's done! 2 months of R&D and a week of soldering and it's done!
(http://i.imgur.com/hxwb4VM.jpg)
Isn't it pretty? :icon_biggrin:
___________________________________________________________________________________________________________________________________________________________
Ok, let's start at the beginning!
Transformer and rectifier:
(http://i.imgur.com/ujFLSkR.jpg)
1.) .68µ/250V capacitor infront of the transformator to smooth out the AC just a bit.
2.) 24V/1.1A transformator bought from a local electronics store. Don't let the writing on it fool you... It is 24V/1.1A.
3.) Just your average everyday full wave bridge rectifier.
4.) Huge-ass inductor of unknown value that i found in an old ATX power supply. Actually helps quite a bit with smoothing out the rectified DC...
5.) Wires going to main board.
___________________________________________________________________________________________________________________________________________________________
Main board:
(http://i.imgur.com/x9I0FXP.jpg)
1.) DC input connector.
2.) sh*t-ton of filtering. 10n, 100n, 10µ, 470µ and 4 1000µ capacitors. This may look like overkill but I assure you, each one of these makes a contribution to lessening the hum. Adding more filtering doesn't help, however removing them results in more hum.
3.) 2 10000µ capacitors that make by far the biggest difference in smoothing out the current. (As if the other capacitors weren't overkill enough... xD)
4.) 12V regulator, 18V regulator and an awesome heat sink from the ATX power supply mentioned earlier.
5.) 2 1000µ capacitors for filtering after the 12V regulator.
6.) 2 1000µ capacitors for filtering after the 18V regulator.
7.) Stage 1 valvecaster circuit with connectors for off-board components.
8.) Stage 2 valvecaster circuit with connectors for off-board components.
9.) LM317 regulator set to 9V (because i didn't have a fixed 9V regulator handy) for Tillman preamp and indicator LEDs
10.) 2 1000µ capacitors for filtering after the 9V regulator.
11.) Tillman preamp circuit.
___________________________________________________________________________________________________________________________________________________________
Off-board components:
(http://i.imgur.com/4O8bxn3.jpg)
1.) Volume and gain POTs for first stage.
2.) Volume and gain POTs for second stage.
3.) Indicator LEDs, foot switches and connectors.
___________________________________________________________________________________________________________________________________________________________
Crème de la crème:
(http://i.imgur.com/WevGVom.jpg)
2 GrooveTube 12AX7s bought at a local music store for 18€ each.
___________________________________________________________________________________________________________________________________________________________
The end result is a heavenly sounding Doublecaster with next to no hum. If there's one thing I learned from this build is that more capacitors = less hum. Nothing new right? Indeed. However I never imagined I'll be using 10 1000µ and 2 10000µ capacitors to eliminate the hum... And yet that's what it took! Now i have next to no hum even when cranking both the gain pots to 9! (The sound I get with both on 10 isn't that good but maybe I'll fix that one day...)
Next step: Building an epic enclosure with the help of a friend!
If anyone needs help with 12AX7 valvecasters or with removing hum feel free to ask. I feel pretty confident that i'll be able to help at least a bit. :)
Couldn't have done it without the help of everyone on this forum! So thanks again! :)
P.S. Wow, this is one huge post! xD
Beautiful work, well done!
Quote from: toplak666 on March 29, 2013, 07:39:15 AM
(http://i.imgur.com/hxwb4VM.jpg)
HOLY HEATSINKS BATMAN!!!
Great looking build! :o
Everything looks beautiful!
I could be wrong (it happens, ask my wife ;)), but I suspect that the transformer might really be rated at 18V secondary with 230V input, and you saw 24V because it was measured without a load. If the transformer output is less than 19.5V under load, your 18V regulator may not have the proper input voltage to operate correctly. I'm interested to know the following::
1) Transformer input voltage,
2) Transformer output voltage, measured with no load, e.g., disconnected from all other circuitry (this may not be possible if it's hard wired),
3) Transformer output voltage, measured with load (the output of your regulators need to have a load for this measurement), and
4) The output voltage of each regulator, measured under load.
It all may turn out fine, but I'm a skeptic by profession. ;)
Edited for grammar. :icon_redface:
Quote from: Jdansti on March 29, 2013, 11:34:44 AM
Everything looks beautiful!
I could be wrong (it happens, ask my wife ;)), but I suspect that the transformer might really be rated as having an 18V secondary at 230V input, and you're saw 24V because it was measured without a load. If the transformer output is less than 19.5V under load, your 18V regulator may not have the proper input voltage to operate correctly. I'm interested to know what the following:
1) Transformer input voltage,
2) Transformer output voltage, measured with no load, e.g., disconnected from all other circuitry (this may not be possible if it's hard wired),
3) Transformer output voltage, measured with load (the output of your regulators need to have a load for this measurement), and
4) The output voltage of each regulator, measured under load.
It all may turn out fine, but I'm a skeptic by profession. ;)
On it! :)
Whoa... Am i ever glad you were sceptical. O_O
Input voltage is 220V.
The transformer actually only gives me 19V without any load...
And falls to only 15.5V with full load!
...In my defense, when I wrote "It is 24V/1.1A." I was measuring with all the filtering already connected but no load so that's what bumped my measurements up...
Now, I knew that the trafo alone gives me 19V and the capacitors bump that up to 24V, however I just assumed that the voltage wouldn't drop by that significant of an amount under load. (facepalm...)
That's also the reason why I simply wrote the trafo is rated at 24V...
Looks like I'll be getting a new higher rated trafo in the near future! :)
Thanks for pointing this out to me man!
No problem!
BTW, I don't know if you have a surplus shop near you, but I found some old, but new in box, 24V doorbell transformers for $1 each at my local surplus shop. Old laptop supplies can usually be filtered and regulated too.
This is my first post, so be gentle with your terminology. I've built a valvecaster and combined it with a Lovepedal COT 50 boost, but now I'm looking for something a bit more intriguing.
Could I build an AC30 top boost preamp and substitute the 12AX7's for AU7's, running it off of 9 volts? ???
Hellou,
Anyone have a schematic, if i want to use 6n2p tubes?
I just finished my first and I LOVE THIS THING! I'm hooked, I need to build more variations.
Here it is. I was too excited to paint the box first. :icon_lol:
(http://i706.photobucket.com/albums/ww70/2266vm/Valvecasterboost_zps5f6a2dad.jpg)
Clips:
Volume 5, Tone 5, Gain 5
http://www.youtube.com/watch?v=iPNvE5oUk98
Volume 5, Tone 5, Gain 8
http://www.youtube.com/watch?v=L_0vt802HYo
Epic thread, guys!
I've been looking to put together a dual preamp to add some tube overdrive/boost to my NS/Stick. I happened on Tesaling's Valvecaster 2.0 (http://www.instructables.com/id/The-Valve-Caster-20-Tube-Boost-and-Overdrive/ (http://www.instructables.com/id/The-Valve-Caster-20-Tube-Boost-and-Overdrive/)), which seems like a nice fit for the guitar side, and there's plenty of tips here for "cleaning up" the boost of a single-tube Valvecaster which seems like it would work well for the bass side.
I already have a cadre of AMB's alpha20's built up that can be used for output (and if necessary, input) buffering, and a lovely-clean bipolar PSU: http://www.twistedpearaudio.com/power/lcdps.aspx (http://www.twistedpearaudio.com/power/lcdps.aspx).
My question is - while really clean, the current output on the LCPDS is not that great. The Alpha 20's ideally need about 100mA each (allowing for headroom). I've heard a range of current requirements for the valvecaster on this thread anywhere from 150mA to 400mA. Should I just look at adding a separate power supply for the tube parts of the circuits or could the LCPDS yet be made to work?
Looking to stick patch the guitar side into the preamp loop of my MPX-G2. :icon_twisted:
Wanted to relay my thanks to the writers of this thread - I've just built my first effects circuit (a Valvemaster) and I think it sounds pretty good for about £10 of parts plus some scavenging! Not mounted it in its enclosure yet - might upload a photo when I do...
A question to all - why are commercially produced valve pedals not more popular? The Vox Cooltrons (low voltage starved plate like our own beloved Matsumi boxes and variants) are discontinued, as are the Electro Harmonix Hot tubes pedals. You can get them from Blackstar at more than I paid for my amp (and indeed amp and guitar put together!) - but they aren't exactly all over the place, are they? Seems strange, given the fun I'm having with mine! Be interested in your comments...
Beavis what program do u use for drawing those schems up?
Can I decrease plate voltage by lowering the values of r2 and r3 on the standard schematic? Or do the plates already get the full 9 volts?
If that wouldn't work I can just build a charge pump.
R2 and R3 (220k and 100k, right?) set the gain of the stage. Decreasing the values will lower your overall gain, increasing them will increase gain. As for the full 9V on the plates, there should be a drop from the resistor. My first gain stage plate usually in the 6-8V range (I run mine at 12V instead of 9V personally.) Hope that helps :)
Thanks Tony! So in order to increase headroom I'd probably need a higher plate voltage than grid voltage?
Quote from: Supakas on April 02, 2013, 01:52:52 PM
Hellou,
Anyone have a schematic, if i want to use 6n2p tubes?
6n2p have the same rating as 12ax7 but 6volts only on the heater, 9v would quickly kill the heaters, you would need to lower the voltage for pins 4 and 5, leave them connected as you see but to 6.3 volts if possible. also 12ax7's are not known to do well in this low voltage design, so their use may very. I have a metric but ton of them, and when I build amps I put a switch in v2 where this tube loves to be, as it seams to handle saturation better IMO. In this design, I still go back to the 12au7 and at7..
This have been a long thread so I haven't read it all. From earlier posts, valvecaster doesn't work well with 12ax7. Does that mean it won't really work at all if I place a 12ax7 on it?
Also, I've looked at the Persuader schematic and looks like it worked well with 12ax7. The only difference I spotted is how we supply voltages on PIN 1 and 6. The pin 4 and 5 is I think similar if not the same as the Valvecaster.
http://www.modkitsdiy.com/sites/default/files/product_files/the_persuader_schematic.pdf (http://www.modkitsdiy.com/sites/default/files/product_files/the_persuader_schematic.pdf)
Any ideas how I could make 12ax7 work on this circuit? perhaps put a 9v+ supply on Pin 9? not sure really.
Thanks!
a 12ax7 works, most people do not like the sound, not much boost at 9 volts. do not put 9volts on pin 9. Its the mid point of a 12v heater CKT. With the 9v valvecaster we are running the heaters at a lower voltage, meaning we do not get full emissions from the cathode. the 12ax7, because of trasconduction and plate characteristics, only puts out 3ma at its best, which makes the voltage swing over the plate resister less (voltage == current X resistance) , than say a 12AU7 allowing 7ma to flow.
so to wrap up, you can try a 12ax7, and you may like it, but others have not. you can try 12v, I find it works better, or do what some of us have an put 12 on heater and use a voltage multiplier to get 70 or 100v on the plates. in any case this is not a distortion pedal but a booster, so the high gain of the 12ax7 will not get you there. At 100v, well now we have a whole different story and design.
Try the standard and then look up valvemaster I think its starting on page 131 or the thread, I have a simple voltage booster at 60v on one, sounds nice..
Quote from: iccaros on April 19, 2013, 02:02:27 AM
a 12ax7 works, most people do not like the sound, not much boost at 9 volts. do not put 9volts on pin 9. Its the mid point of a 12v heater CKT. With the 9v valvecaster we are running the heaters at a lower voltage, meaning we do not get full emissions from the cathode. the 12ax7, because of trasconduction and plate characteristics, only puts out 3ma at its best, which makes the voltage swing over the plate resister less (voltage == current X resistance) , than say a 12AU7 allowing 7ma to flow.
so to wrap up, you can try a 12ax7, and you may like it, but others have not. you can try 12v, I find it works better, or do what some of us have an put 12 on heater and use a voltage multiplier to get 70 or 100v on the plates. in any case this is not a distortion pedal but a booster, so the high gain of the 12ax7 will not get you there. At 100v, well now we have a whole different story and design.
Try the standard and then look up valvemaster I think its starting on page 131 or the thread, I have a simple voltage booster at 60v on one, sounds nice..
Thanks a lot for the very helpful information iccaros.
Re: Do not put 9v on pin 9.
Ok noted.
Alright since most have find it better on a 12v, I'll start with that. As you've suggested I'll read through page 131 however, I don't have much confidence dealing with high voltages yet. Is 60v enough to kill me if I accidentally touch these things? If yes, i think i'll better pass :)
60v will make you burn in flames in 10 seconds, and your ashes will be your only legacy...
jokes apart, the persuader is just another story...playing with pure tube schematics is more difficult than just push a tube with a (mosfet in the persuader case) booster...yes you can do it, but then you got an hybrid circuit and the tube gets less involved in the outcoming tone, so less mandatory (at least in my eyes)
just look at the schematic, no cathode resistors or capacitors...I guess the tube used that way gives very little to the overall performance...but it's just my guess, driven by a dislike of hybrid circuits.
basically you have a super hard on to boost the tube - you still can try it with the original valvecaster schem or the valvemaster. I wrote several times that I find the valvecaster to be a little on the bass side, so while I descourage the use of an LPB before it (being too dark to my ears), a different kind of booster would be a good push - I personally tried the tilman and got nice results, guess the sho is even better as it has a good "presence".
When I tried it with a 12ax7 at 24V, it sounded pretty good to me... I'm currently working on a low voltage clean all tube boost with a 12AT7 at 24V. It's sounding pretty good ATM, but it still needs a bit of tweaking to get it perfect. I'll probably post a schematic and samples soon.
Quote from: Renegadrian on April 19, 2013, 07:54:03 AM
60v will make you burn in flames in 10 seconds, and your ashes will be your only legacy...
jokes apart, the persuader is just another story...playing with pure tube schematics is more difficult than just push a tube with a (mosfet in the persuader case) booster...yes you can do it, but then you got an hybrid circuit and the tube gets less involved in the outcoming tone, so less mandatory (at least in my eyes)
just look at the schematic, no cathode resistors or capacitors...I guess the tube used that way gives very little to the overall performance...but it's just my guess, driven by a dislike of hybrid circuits.
basically you have a super hard on to boost the tube - you still can try it with the original valvecaster schem or the valvemaster. I wrote several times that I find the valvecaster to be a little on the bass side, so while I descourage the use of an LPB before it (being too dark to my ears), a different kind of booster would be a good push - I personally tried the tilman and got nice results, guess the sho is even better as it has a good "presence".
Thanks Adrian for the suggestions. With the parts I bought today, I'm going into the SHO+Valvecaster.
Quote from: psychedelicfish on April 20, 2013, 05:28:06 AM
When I tried it with a 12ax7 at 24V, it sounded pretty good to me... I'm currently working on a low voltage clean all tube boost with a 12AT7 at 24V. It's sounding pretty good ATM, but it still needs a bit of tweaking to get it perfect. I'll probably post a schematic and samples soon.
Thanks, I'll look forward to your schematics soon.For now I'll just go with the SHO+Valvecaster built.
OK I've read at least through 100 mind-numbing pages of this thread and everything's starting to blur together, so forgive me if I'm reposting old questions here... :icon_redface:
Has anyone tried putting a TS-808 (or clone) in front of it to get more distortion? Do you guys recommend running this linear or in parallel blended with a clean signal? Anyone running this in a HiFi amp/cab setup or direct?
Quote from: Ripdivot on March 10, 2008, 01:28:04 AM
Here is the schematic for my latest dual 12AU7 circuit. It is currently still on the bread board and I think it sounds great. It is designed to run on 9 volts. It goes from clean boost all the way up to "brown" type gain. It cleans up nice with the guitar volume as well.
(http://img80.imageshack.us/img80/8932/lvlrev3bmprk9.th.png) (http://img80.imageshack.us/my.php?image=lvlrev3bmprk9.png)
Sorry to dredge up an old post but has anyone else tried this variant? I'm currently proto-boarding it...looks a bit more refined from my limited first glance at it.
mmm I guess that could be done, altough I find it too much...but yeah guess what you would find if you open a tube driver or a tonebone...yeah a 4558 pushing the tube!!!
Hello folks:
I was last on this thread about a year ago all enthused about progressing to the next stage of pedal building with a tube overdrive pedal .... I bought all the stuff, I breadboarded one (and it worked!), but then after reading many pages of this thread I realized that there was still a lot of uncertainty about which circuit is the best. So I put it aside for awhile. 9 volt? 12 volt? 12AX7? 12AU7? Well, I am back and I was hoping that there is a concensus now on which is the best way to go and that you all can direct me to the schematic for the consensus tube overdrive. Thanks.
@Henry
Sorry to say there will never be a consensus , this is music and everyone has a different want and need. since you have a bread board, try the different ways, play with it, if you like it that is the best one, if not.. try the next.
Tubes at low voltage are fun as they are hard to kill unlike a transistor. AS LONG as you do not screw up the heaters.. that is..
But if you hook up a tube backwards at 12 or 24 volts.. no harm no foul..
Have to agree with iccaros on the consensus and experimenting part. However if you don't know where to start and are looking for versatile sound I'd suggest a 12AX7 double valvecaster with the valvemaster circuit. You'd need 12V for the heaters and at least 18V for everything else... I found that 12AX7s are more or less useless with anything less than 12V, however with 18V or more they sound great. With this design you'd be able to get some nice crunchy crunch from the first stage and (at least from my experience) HEAVENLY drive with the second stage kicked in.
Anywho, those are my two cents... Hope it helps. :)
Toplak666:
Thanks. Perhaps "consensus" was the wrong word to use, but your response is exactly the type of suggestion I was looking for. It sounds good too. I am going to look for the schematic.
I wanted to thank everyone on this forum - I've built my first stompbox (a valvemaster housed in an old, non-working, wah enclosure). I think it sounds great on single coils and humbucker, giving my low budget but reasonable set-up (solid bodied Pacifica and H&K Blue 60r) a bit of valvey goodness! A bit farty on high gain - what could I try to improve this? Different valve or change some R and C values?
(http://i537.photobucket.com/albums/ff336/rhodrib/Valvepedal.jpg)
change your coupling cap, use smaller number, if your using .1 use a .01 or .022 ect.. you will roll off some more bass.
Hi, this thread is very informative, I have learned a lot about power supply and tubes in particular. One thing that concerned me is the power to be used on the circuit. I have read that the heater must be 12 volts to pin 5 and Ground to 4 or vice versa for the tube to be optimized and can lived long. I have understood that the circuit itself can have a different voltage, it can be from 9v-whatever is the maximum. I have a charge pump (for some of my pedals) right now based on madbeans layout with two outputs, 15v and 18v. I wanted to use the 18v to supply this pedal, but it won't be ideal for the heater, therefore, I need to give 12v to it.
1. How can I integrate A 12V regulator (and other components) inside the circuit and connect it to the heater while its Vin comes from the 18v supply of the entire circuit?
2. What are the necessary components to be placed aside from a 7812 regulator?
The main PS I'm using is a 1-spot. I have build my layout based on the Dual Caster:
(http://i355.photobucket.com/albums/r445/jmwreck/SCHEME-4.jpg)
(http://i355.photobucket.com/albums/r445/jmwreck/LAYOUT.jpg)
-----
If you find errors on my layout, please let me know.
It is a stock Dual Caster based on THIS (http://www.aronnelson.com/DIYFiles/up/12AU7-6111_Valve_Caster_Summary_Rev002.pdf)
use a 5 volt regulator and shunt it to give 6.3 (2 diodes on ground should do it, but what ever diode you use look up the voltage drop, you want about 1.3 volts total) and use the alternative wiring, pin 4 and 5 tied together with + 6 volts and pin 9 ground. you will need a heat sink and notice the tab on the LM7805 is positive so you will need a mica separator. two tubes will pull 600ma for heaters in 6.3 volt mode..
Quote from: iccaros on May 07, 2013, 11:07:58 AM
use a 5 volt regulator and shunt it to give 6.3 (2 diodes on ground should do it, but what ever diode you use look up the voltage drop, you want about 1.3 volts total) and use the alternative wiring, pin 4 and 5 tied together with + 6 volts and pin 9 ground. you will need a heat sink and notice the tab on the LM7805 is positive so you will need a mica separator. two tubes will pull 600ma for heaters in 6.3 volt mode..
is there any other way than this and what is the difference if I'm going to use the 12v regulator instead of the 5v? thanks :)
You can't run a 12V regulator using a 9V supply. Steve's option allows you to power the heaters in parallel with 6V instead of series using 12V. Here's a drawing that should explain it.
(http://i1160.photobucket.com/albums/q485/jdansti/9122FD67-871A-4520-A7E7-C5B53D8B5ADC-4671-000005CC9ED4FB63.jpg)
Edit: I'm not 100% sure about this, but the reason Steve probably didn't recommend using a 12V regulator on the 18V output of your charge pump is the pump can't provide the current you need for the heaters.
QuoteYou can't run a 12V regulator using a 9V supply.
yup, I know this, oh so what if I'll change the 15v output from my charge pump to 12v, and from there, I will power the entire circuit with 12v instead of 18v? is it possible? I was thinking of doing the valvemaster instead of the dual caster. I realized that it's a little complicated for my 1st tube project.
QuoteEdit: I'm not 100% sure about this, but the reason Steve probably didn't recommend using a 12V regulator on the 18V output of your charge pump is the pump can't provide the current you need for the heaters.
how about the mica separator?
thanks
>yup, I know this, oh so what if I'll change the 15v output from my charge pump to 12v, and from there, I will power the entire circuit with 12v instead of 18v? is it possible? I was thinking of doing the valvemaster instead of the dual caster. I realized that it's a little complicated for my 1st tube project.
It depends on the max current out if your charge pump and the current draw of your heaters. Look at the data sheets to see what they are, and if the total current draw for the heaters and the test of the circuit is less than the max current of your charge pump, you're fine. If not, it's back to the drawing board. :)
If the charge pump can't handle the heaters, you might want to look around (thrift stores, your friends, maybe stashed somewhere in your house) for a wall wart or laptop power supply that puts out between 12V and 35V AC or DC. From there, it's easy to get the voltages you want.
Quote from: Jdansti on May 08, 2013, 07:07:54 AM
I have a 12v 500ma dc adaptor I used once on my cmoy headphone amp
^Ok. You're getting closer. You need two bits of information now.
1) Do you know if your 12VDC PS is regulated? If you don't know, plug it in and check the voltage out. If it hangs around 12V, you're probably OK. If it's >13V it's probably unregulated and could potentially put more than 12.6V on the heaters.
2) Lets add up the currents of your circuit and see if we're under 500mA. I don't mind doing the work, but I want to help you learn how to do this. I'll start you off with a list and let you research the data sheets for answers. Let us know if you hit a road block.
Find these currents
- tube heater @ 12.6V series X number of tubes = ___mA
-Cathode Current (not "peak") X #of cathodes (2 for one tube and 4 for two tubes)= _____mA
- charge pump input current (if running off of this PS) = _____mA
Add the above currents and you should have a good idea of the current draw of the system. You might want to add in a 10% factor to cover the rest of the circuit not accounted for above. If it all adds up to less than 500mA, your good to go, although I would try to leave some room for error. The PS may not have an automatic reset. If you exceed it's capacity you could blow an internal fuse. (I blew one that had an internal fuse recently-it's DOA :( ).
the max *** the Madbeans charge pump can supply is 20ma.. so it can not run your heaters, even at 12v.
A 6 volt regulator is only 4 parts, 1 regulator, 3 diodes. and would allow you to use your current power supply and the charge pump for the plates
(https://dl.dropboxusercontent.com/u/14312589/6.3v%20power.jpg)
Quote
1) Do you know if your 12VDC PS is regulated? If you don't know, plug it in and check the voltage out. If it hangs around 12V, you're probably OK. If it's >13V it's probably unregulated and could potentially put more than 12.6V on the heaters.
looking at the power supply shell, there's an "IC Regulated" label near the 12Vdc 500ma. I might check it with a meter later.
Quote
2) Lets add up the currents of your circuit and see if we're under 500mA. I don't mind doing the work, but I want to help you learn how to do this. I'll start you off with a list and let you research the data sheets for answers. Let us know if you hit a road block.
Find these currents
- tube heater @ 12.6V series X number of tubes = ___mA
12.6 X 1 =
12.6 (since I might do the valvemaster instead of the twin)
-Cathode Current (not "peak") X #of cathodes (2 for one tube and 4 for two tubes)= _____mA
20ma x 2 cathodes(1 tube) =
40- charge pump input current (if running off of this PS) = _____mA
Quote from: iccaros on May 08, 2013, 10:21:38 PM
the max *** the Madbeans charge pump can supply is 20ma.. so it can not run your heaters, even at 12v.
and reading madbean's documentation, it is 20ma, so:
20ma= total will be 12.6 + 40 + 20 = 72.6 + 10% =
±80maam I correct?
QuoteA 6 volt regulator is only 4 parts, 1 regulator, 3 diodes. and would allow you to use your current power supply and the charge pump for the plates
what exactly are the diodes?
and is it going to look like this on the entire scheme?
(http://i355.photobucket.com/albums/r445/jmwreck/VALVEMASTER.png)
thanks guys
>am I correct?
You've listed the voltage and not the current for the tube heaters. Look at this data sheet and you'll see that when you apply 12.6V across the two heaters in series, the current draw is 0.15A (150 mA).
http://www.wooaudio.com/docs/tube_data/12AU7.pdf
If you use one tube, your heater current would be 150mA.
Your cathode current is correct at 40mA
Your charge pump is listed as 20mA
The total for these is 210mA.
Add 10% and your estimate is 231mA, less than 1/2 your PS rating. You should be good with one tube.
If you were to add a second tube, you'd double the heater and cathode currents:
Heaters=300mA
Cathodes=80mA
Charge Pump=20mA
Other: 40mA (estimated)
Total: 440mA
You'd still be under 500mA, but its starting to get close. If our estimate of the "other" current draw is too low, you might exceed the PS current rating.
As for your question about Steve's recommendation, I'm guessing that you'd use 1N400X. We've already determined that you're under 500mA, so you could use anything from 1N4001 to 1N4007.
Edit:
I just looked at your latest schematic and you have a problem with the power. You have the charge pump providing the voltage to the regulator. The regulator's current requirement far exceeds the charge pump's output current. You need to separate regulator and heaters from the rest of the circuit like this:
(http://i1160.photobucket.com/albums/q485/jdansti/F2396379-5E17-4DE7-AB73-48ABAC846AE3-5699-00000733209B7397.jpg)
Quote from: Jdansti on May 09, 2013, 02:52:18 AM
I just looked at your latest schematic and you have a problem with the power. You have the charge pump providing the voltage to the regulator. The regulator's current requirement far exceeds the charge pump's output current. You need to separate regulator and heaters from the rest of the circuit like this:
1. all of this (your revisions on my schematic) will be useless (no more regulator) if I'm going to use my 12v dc 500ma and supply both main circuit and heaters with 12v, right?
2. I understood your revisions and now looking at it, the madbean charge pump has enough current (20ma) to supply the main circuit without the heaters connected to it? if so, then I'll follow your layout.
sorry I should have been more clear, almost any diode will work, but the 1N4001 drop .7 volts (2 = 1.4v) . For the two in series to ground we are looking for the 1.3 volts to raise the ground reference so the regulator thinks its putting out 5 volts but its putting out 6.3, so a good voltage ranges between 5.67v and 6.93 (6.3v +/- 10%) if I did my math right...
Also I do not believe that tube at low voltage will pass more than 3ma over its cathode, at low voltage it acts a lot like a 12u7 http://www.nj7p.info/Common/Tube/SQL/Tube_query.php?Type=12U7
Quote from: jmwreck on May 09, 2013, 03:33:20 AM
2. I understood your revisions and now looking at it, the madbean charge pump has enough current (20ma) to supply the main circuit without the heaters connected to it? if so, then I'll follow your layout.
yes 20ma is plenty to run this with out heaters, it will even work for your two tube design before, it was the heaters that were killing you. :)
>1. all of this (your revisions on my schematic) will be useless (no more regulator) if I'm going to use my 12v dc 500ma and supply both main circuit and heaters with 12v, right?
It depends on whether you want to use the charge pump to get more headroom.
Here's with the charge pump:
(http://i1160.photobucket.com/albums/q485/jdansti/CDBF21BF-F1BC-4090-9180-EE3F7F918B17-5699-00000795AF04815D.jpg)
Here's without the charge pump:
(http://i1160.photobucket.com/albums/q485/jdansti/F7D80BF7-C8A6-490D-A349-9A42E50D5C3D-5699-00000795B963C423.jpg)
thanks. now Ive seen my 12vdc adaptor is center +, im gonna switch the wire.
I wire almost everything center positive as it matches other electronics use. Only effects I expect to run off my 1-spot do I wire negative tip.
I have a masking tape "flag" near the plugs on all of my power supplies labeled with the voltage, AC or DC, and the plug polarity. I also label the jacks on the pedals too.
Quote from: Jdansti on May 09, 2013, 12:05:56 PM
I have a masking tape "flag" near the plugs on all of my power supplies labeled with the voltage, AC or DC, and the plug polarity. I also label the jacks on the pedals too.
I use these --> http://www.amazon.com/Ziotek-Ties-With-Labeling-Plate/dp/B000BSHLJO for that purpose, works well and durable. I am starting to use them in amp builds to label B+ and 2_EQ. This way I can trace the layout better.
Great idea, and much cleaner than tape. I think I've seen those at Home Depot-I'll have to check next time I'm there.
Quote from: iccaros on May 05, 2013, 06:42:13 PM
change your coupling cap, use smaller number, if your using .1 use a .01 or .022 ect.. you will roll off some more bass.
Thanks for answer, Iccaros - can I check what you mean by coupling cap - is that the last one before the output i.e. it couples to the next stage? I've built my pedal according to the Valvemaster circuit on p131 - so C3 = 1uf.
Many thanks!
Quote from: toplak666 on May 04, 2013, 10:37:13 AM
I'd suggest a 12AX7 double valvecaster with the valvemaster circuit. You'd need 12V for the heaters and at least 18V for everything else... I found that 12AX7s are more or less useless with anything less than 12V, however with 18V or more they sound great. With this design you'd be able to get some nice crunchy crunch from the first stage and (at least from my experience) HEAVENLY drive with the second stage kicked in. ... Hope it helps. :)
Toplak666:
I searched this thread for the schematic for the "double valvecaster with the valvemaster circuit" that you suggested. Is this the schematic (below) for that circuit? The schematic says 12AU7 and you suggested the 12AX7 double valvecaster w/ valvemaster circuit. Is it the same circuit with 12AX7 tubes instead of 12 AU7 tubes? Or is there a different schematic for the 12AX7 circuit? Thanks.
(http://i1126.photobucket.com/albums/l603/henry7895/ValveMasterschematic.jpg) (http://s1126.photobucket.com/user/henry7895/media/ValveMasterschematic.jpg.html)
Quote from: valve999 on May 09, 2013, 03:51:10 PM
Quote from: iccaros on May 05, 2013, 06:42:13 PM
change your coupling cap, use smaller number, if your using .1 use a .01 or .022 ect.. you will roll off some more bass.
Thanks for answer, Iccaros - can I check what you mean by coupling cap - is that the last one before the output i.e. it couples to the next stage? I've built my pedal according to the Valvemaster circuit on p131 - so C3 = 1uf.
Many thanks!
There are several locations, you can change c3 but you may find a better sound by changing c2 to a .0022, or by changing the cathode bypass capasitors (the 10uf) to a 1 or .1. if you roll off bass early your not boosting frequencies in latter stages.
Quote from: Henry89789 on May 09, 2013, 03:58:24 PM
(http://i1126.photobucket.com/albums/l603/henry7895/ValveMasterschematic.jpg) (http://s1126.photobucket.com/user/henry7895/media/ValveMasterschematic.jpg.html)
What happens to pin 9 in this circuit ? Is it simply not connected ?
Hemmel:
I don't know but your question just helped me notice that is not the schematic for the dual valvecaster with valvemaster circuit I am looking for.
Quote from: Hemmel on May 09, 2013, 04:22:47 PM
Quote from: Henry89789 on May 09, 2013, 03:58:24 PM
(http://i1126.photobucket.com/albums/l603/henry7895/ValveMasterschematic.jpg) (http://s1126.photobucket.com/user/henry7895/media/ValveMasterschematic.jpg.html)
What happens to pin 9 in this circuit ? Is it simply not connected ?
No, it's not connected because the heaters are powered in series. Substitute your 9V power for the 12V shown below.
(http://i1160.photobucket.com/albums/q485/jdansti/9122FD67-871A-4520-A7E7-C5B53D8B5ADC-4671-000005CC9ED4FB63.jpg)
Quote from: Henry89789 on May 09, 2013, 09:19:21 PM
Hemmel:
I don't know but your question just helped me notice that is not the schematic for the dual valvecaster with valvemaster circuit I am looking for.
for a dual caster as its called, just repeat the same pattern.
(http://juansolo.demon.co.uk/stompage/schematics/Misc/666SBB.jpg)
using the right layout, does it have enough current to power the heaters as well as the main circuit? coz based on this statement:
Quote(Renegadrians Voltage Multiplier), you'll get approx 60v from a 9v supply, 80v from a 12v supply and around 120v from a 18v supply. This charge pumped voltage is very low current, which is why you have to run the heaters from the source supply as they are the high current draw bit.
heaters needs to have a different source.
**Sorry for this question, I haven't seen a clear finished product of a Valve pedal. Using a charge pump for the main circuit and a 12v regulated to the heaters. Does it mean that there are two DC jacks for the pedal and that it obviously share the same ground?
>using the right layout, does it have enough current to power the heaters as well as the main circuit? coz based on this statement:
I'm not familiar with this circuit, but it appears that the 9V supply branches off to the 6V regulator and to the charge pump as I indicated here (assume that the regulator is a 7806-the diodes shown in your layout may not be the same):
(http://i1160.photobucket.com/albums/q485/jdansti/F2396379-5E17-4DE7-AB73-48ABAC846AE3-5699-00000733209B7397.jpg)
>**Sorry for this question, I haven't seen a clear finished product of a Valve pedal. Using a charge pump for the main circuit and a 12v regulated to the heaters. Does it mean that there are two DC jacks for the pedal and that it obviously share the same ground?
If you use the "Boob Board", you don't need the 12V supply. Your 9VDC supply is regulated to 6VDC and supplies the two heaters in parallel. As shown above and below on the right:
(http://i1160.photobucket.com/albums/q485/jdansti/80840F27-49F0-4D52-8215-CBDDD983A06E-6474-0000081541184B5F.jpg)
You only need one DC jack tied to the 9VDC point on the left side of the board. The 6VDC on the right side goes to the heater pins 4 and 5 as shown in my modification above. Pin 9 goes to ground. All grounds should be tied together at one point.
If you decide to forgo the Boob Board, you still only need one DC jack. The 12V supply feeds the tube heaters in series and supplies the input to your charge pump. The output from the charge pump feeds the rest of the circuit as shown here:
(http://i1160.photobucket.com/albums/q485/jdansti/CDBF21BF-F1BC-4090-9180-EE3F7F918B17-5699-00000795AF04815D.jpg)
Quote from: Henry89789 on May 09, 2013, 03:58:24 PM
I searched this thread for the schematic for the "double valvecaster with the valvemaster circuit" that you suggested. Is this the schematic (below) for that circuit? The schematic says 12AU7 and you suggested the 12AX7 double valvecaster w/ valvemaster circuit. Is it the same circuit with 12AX7 tubes instead of 12 AU7 tubes? Or is there a different schematic for the 12AX7 circuit? Thanks.
(http://i1126.photobucket.com/albums/l603/henry7895/ValveMasterschematic.jpg) (http://s1126.photobucket.com/user/henry7895/media/ValveMasterschematic.jpg.html)
Ye, sorry bout that... I should have been more specific about what I ment by "double valvecaster with the valvemaster circuit". Yes, this is the right circuit! The schematic should be pretty much the same for 12AX7s... However, instead of 9 volts you'll need 12 volts for the heater pins and 18 volts or more for everything else. Maybe I'll draw you up a schematic later if I find the time.
Quote from: toplak666 on May 10, 2013, 05:40:03 AM
Quote from: Henry89789 on May 09, 2013, 03:58:24 PM
Ye, sorry bout that... I should have been more specific about what I ment by "double valvecaster with the valvemaster circuit". Yes, this is the right circuit! The schematic should be pretty much the same for 12AX7s... However, instead of 9 volts you'll need 12 volts for the heater pins and 18 volts or more for everything else. Maybe I'll draw you up a schematic later if I find the time.
I will finish up a drawing tonight, I am on travel for work so it my be a little latter. But its basic, if you have 9v and multiply that to 18 then you take the 9v and tap off to a regulator getting 6v for the heaters, another tap goes to to the multiplier.
(http://i.imgur.com/ZWMg0SC.jpg)
There ya' have it. Ain't she a beaut? ;) With this design you should be able to get nice crunch tones from the first stage and great drive sounds from the second stage.
This should work with all 12A_7 tubes, but keep in mind that while other tubes should work with plate voltages above 9v, 12AX7s need at least 18v for the plates. They just don't sound right otherwise... I can't say for sure but I suspect 12AT7s would require 18v too.
The first volume pot is completely optional but I recommend leaving it in. You can get more sounds by fiddling with it while using both stages.
This is ment to be used with two true bypass circuits. One for the first stage and one for the second. Didn't bother putting those in the schematic because I figured if you can wire up this circuit you should be able to wire in a bypass...
You diystompboxes veterans are welcome to fix any mistakes in the schematic. I'm still pretty new to tube circuits... :)
Toplak666:
Thanks for taking the time to draw up that schematic. She is indeed "a beaut" and an important contribution to this thread. She also represents the highest level to which I expect to go in building pedals. I have gone through pages 80-140 of this thread and haven't found a schematic similar to yours other than the single circuit one I put up. The farthest I have gone so far is building a one tube pedal on the breadboard (w/o switch or bypass). When I first came on here about 2 years ago I didn't even understand schematics. For me the great challenge is to follow the schematic, build that Dual Caster tube pedal and have it work perfectly the first time. So I apologize for being a nag about the schematic. I definitely expect to build it. I already have all the parts. 12 old RCA and Sylvania 12AU7 tubes (obtained used but tested for $3.00 each from a Hammond organ repairman); tube sockets; switches; box; caps; etc. It would be great though if someone could verify that schematic.
that would work, you will find that 10uf on the cathodes have a lot of bass, you can try .1 uf and for resistors 1.5K and for the first stage. really if you can measure 1.5v across the first cathode resistor, will give good enough head room and stay linear, allowing better control for the following stages.
Quote from: Jdansti on May 10, 2013, 02:41:06 AM
looking at the charge pump above, the layout on the right is coming from a 9v then connect to the 9v wire then to a 6v and 60v on the on the other end, it means that its a charge pump that can supply the heaters (6v) and to the main circuit (60v), does it have enough current?
Quote from: iccaros on May 09, 2013, 04:14:41 PM
Quote from: valve999 on May 09, 2013, 03:51:10 PM
Quote from: iccaros on May 05, 2013, 06:42:13 PM
change your coupling cap, use smaller number, if your using .1 use a .01 or .022 ect.. you will roll off some more bass.
Thanks for answer, Iccaros - can I check what you mean by coupling cap - is that the last one before the output i.e. it couples to the next stage? I've built my pedal according to the Valvemaster circuit on p131 - so C3 = 1uf.
Many thanks!
There are several locations, you can change c3 but you may find a better sound by changing c2 to a .0022, or by changing the cathode bypass capasitors (the 10uf) to a 1 or .1. if you roll off bass early your not boosting frequencies in latter stages.
Thanks, Iccaros - I'll give that a go!
Quote from: jmwreck on May 11, 2013, 08:24:59 AM
Quote from: Jdansti on May 10, 2013, 02:41:06 AM
looking at the charge pump above, the layout on the right is coming from a 9v then connect to the 9v wire then to a 6v and 60v on the on the other end, it means that its a charge pump that can supply the heaters (6v) and to the main circuit (60v), does it have enough current?
The 6V is not coming off of the charge pump. It's coming off of the regulator labeled as Q1.
(http://i.imgur.com/eZIYQZY.jpg)
Higher resolution version: http://i.imgur.com/Ag7Rckc.jpg
Thar she blows! This is pretty much what I made for my 12AX7 DoubleCaster except I don't have L2 and actually have two more 1000µF capacitors after L1. This shouldn't cost more than about 15-20$. Cost me a bit more since prices in Europe are higher, but that's still prety cheap for an incredibly clean power supply.
Ok, so the 600mA transformator should supply enough current for at least two tubes. After that we have your basic old bridge rectifier to convert AC to DC. After that we have two inductors. If you choose to include them, make them as big as you can fit in your enclosure. The reason I labled them as "Optional" is because in order to get a noticable effect from them they need to be relatively big, so they may not fit in everyone's enclosures.
Now for the filter capacitors... If you can eliminate all humm with fewer capacitors then HALLELUJAH! But this is what it took to completely eliminate humm for me and frankly capacitors are pretty cheap so why not add a few more while you're at it? :)
After that we have a 12V and 18V regulator and a few more capacitors.
Now if you already have a powerfull wall wart and want to use that then just connect it to the two regulators and ignore everything infront of that.
There you have it! Clean, powerfull and relatively cheap power supply! Feel free to fix any problems in the schematic! I'm sure there are many. :)
Quote from: Renegadrian on April 19, 2013, 07:54:03 AM
jokes apart, the persuader is just another story...playing with pure tube schematics is more difficult than just push a tube with a (mosfet in the persuader case) booster...yes you can do it, but then you got an hybrid circuit and the tube gets less involved in the outcoming tone, so less mandatory (at least in my eyes)
just look at the schematic, no cathode resistors or capacitors...I guess the tube used that way gives very little to the overall performance...but it's just my guess, driven by a dislike of hybrid circuits.
@Renegadrian.. I now understand why you dislike hybrid circuits. I just finished my SHO + Valvecaster today and it sounds like a Russian big muff if you crank everything up. I like the valvecaster alone but I guess there's no turning back since I'm done already. Plus I don't like the CRACKLE sound on both the valvecaster gain(using B500K) and the SHO gain(5K) when I turned those pass by 80% of their respective ranges.
Lesson of the story: Listen to suggestions :icon_evil: :icon_evil:
Here are some pics:
(http://farm8.staticflickr.com/7436/8729502521_249b43c565.jpg)
(http://farm8.staticflickr.com/7291/8729504553_b2ed872bfe.jpg)
(http://farm8.staticflickr.com/7318/8734963404_4a9554d9a1.jpg)
(http://farm8.staticflickr.com/7296/8733845253_2344d51700.jpg)
This is very cool, I've wanted to do this for a long time but didn't know it was possible. A good source for power supplies is thrift stores, you can usually find 9vDC with + and - centers and different mA's. Thanks for a great site!
which one is good for this circuit?
I only have these options.
(http://altomusic.com/shop/images/product/118177-27275099345d4ba6a26329c74cef47a3.jpeg)
OR
(http://reflexion-arts.com/productos/fabricantes/valvulas/electro-harmonix/electro-harmonix-12au7-gold/logo)
here is my layout:
(http://i355.photobucket.com/albums/r445/jmwreck/VALVEMASTERSCHEME.png)
(http://i355.photobucket.com/albums/r445/jmwreck/VALVEMASTERPOWERSCHEME.png)
(http://i355.photobucket.com/albums/r445/jmwreck/VALVEMASTERLAYOUT.png)
I've tested 3 types..
Electro harmonix
Stlvnia
And RCA
All sound good the RCA sounds best :)
Hi,
i have one question, i'm new to this, so please sorry my lame questions.
I decided to build valvecaster according to this scheme http://www.aronnelson.com/gallery/main.php/v/Renegadrian/Valvecaster+v0_5.jpg.html (http://www.aronnelson.com/gallery/main.php/v/Renegadrian/Valvecaster+v0_5.jpg.html) I used parts with same values.
Problem is that there's to much noise (hum) in the signal, doesn't matter if i play or not, there's lot of hum, but if I start to play, I can hear what I'm playing but it's in background.
I used valve 12AX7, because i have few of them at home, they sholud be ok, all parts are new except pots and I'm not sure if they're ok, but when I turn them around they're changing sound or volume can turn it off. I used power supply with 9DC and also 12DC, result was almost same. I read that it's better to use 12AU7, but and I said to myself that it shouldn't such a difference. Is it possible that AX makes such a noise and if I use AU it can work allright? Or ther's some other problem. Thanks for your answers.
you grounded your in and out sockets? or mounted them in a grounded metal box?
thread is too long!
I'm guessing your power supply is at fault for both your problems... If your power supply doesn't have extremely good filtering then 12AX7s will produce a nasty hum. Also, if your power supply can't provide enough current then that can lower output volume AND cause noise.
This is just a hunch though so take it for what it's worth...
Quote from: Lurco on May 31, 2013, 03:01:57 AM
you grounded your in and out sockets? or mounted them in a grounded metal box?
I think they're grounded, it's not in a box, yet. I want to make it work on the table before mounting.
On PCB i made one ground for all connections, so there's going ground from power supply, in ond out jacket pots, etc. I'm not 100% sure if it's right, but with my basic understanding of electronics, I think it's ok.
Quote from: toplak666 on May 31, 2013, 03:32:29 AM
I'm guessing your power supply is at fault for both your problems... If your power supply doesn't have extremely good filtering then 12AX7s will produce a nasty hum. Also, if your power supply can't provide enough current then that can lower output volume AND cause noise.
This is just a hunch though so take it for what it's worth...
It's possible0, at first I used older power supply with changable output voltage, it was 12V/500mA, then I used older PC power supply and effect was same, I thought that PC power supply have a good filtering.
I made recording of this problem, pls at first put volume on your speakers down, that noise is loud.
https://soundcloud.com/burdin84/valvecater-problem (https://soundcloud.com/burdin84/valvecater-problem)
around 0:08 I turned with volume pot to 0.
Maybe problem can be in capacitors? I bought caps with designated capacity, but according to what I saw on the interenet it's different type, ceramic I think. Here's a picture.
(http://s23.postimg.org/w82p373d7/2013_05_31_13_59_48.jpg)
I have finally build the boobtube, I put a sho in front and klon buffer after it, but there's no overdrive at all, I tried to maximize the gain knob of the tube, all I can hear is a volume boost, I have also tried maximizing my sho, but no drive at all. I'm using a tungsol 12au7, the tube lit up just a tiny spark of orange, I have the Renegadrian's multiplier with a 12v source, I have also tried replacing the gain pot to 500k, it doesn't help. I've listened to some demo and the overdrive sound is really there, all I can hear in my build is just a volume boost with no crunch whatsoever.
Quote from: Burdin on May 31, 2013, 07:39:26 AM
Quote from: Lurco on May 31, 2013, 03:01:57 AM
you grounded your in and out sockets? or mounted them in a grounded metal box?
I think they're grounded, it's not in a box, yet. I want to make it work on the table before mounting.
On PCB i made one ground for all connections, so there's going ground from power supply, in ond out jacket pots, etc. I'm not 100% sure if it's right, but with my basic understanding of electronics, I think it's ok.
Quote from: toplak666 on May 31, 2013, 03:32:29 AM
I'm guessing your power supply is at fault for both your problems... If your power supply doesn't have extremely good filtering then 12AX7s will produce a nasty hum. Also, if your power supply can't provide enough current then that can lower output volume AND cause noise.
This is just a hunch though so take it for what it's worth...
It's possible0, at first I used older power supply with changable output voltage, it was 12V/500mA, then I used older PC power supply and effect was same, I thought that PC power supply have a good filtering.
I made recording of this problem, pls at first put volume on your speakers down, that noise is loud.
https://soundcloud.com/burdin84/valvecater-problem (https://soundcloud.com/burdin84/valvecater-problem)
around 0:08 I turned with volume pot to 0.
Maybe problem can be in capacitors? I bought caps with designated capacity, but according to what I saw on the interenet it's different type, ceramic I think.
It's been a long time since I built my Valvecaster, but my memory is that mine was noisy until I got it in an enclosure. No guaranties that this would work in your case! ;)
I'm worry that problem is not in enclosure, because yesterday I realize few things.
At first I borrowed good filtred power supply.
I'm using this with bass guitar and when I close the tone on bass, noise disapears, it's same with different bass.
Second thing is that this circuit taking to much signal, I tried it with old Fender Bassman, volume was around half and noise was according to this level, but signal was to weak, I was able to hear it, but it wasn't according to the volume level of an amp. This was with full opened Tone on the bass, when I closed it, there wasn't any hum but signal was stil weak.
Unfortunately I don't know where to looking for problem. I make control if there's no shorts on the circuit and if the welds are ok, and everything seams fine.
So maybe the enclosure can solve the noise, but I guess that it wouldn't solve problem with weak signal.
(https://fbcdn-sphotos-c-a.akamaihd.net/hphotos-ak-prn1/935519_551844104856658_747807272_n.jpg)
(https://fbcdn-sphotos-b-a.akamaihd.net/hphotos-ak-prn2/603067_551844368189965_1638543239_n.jpg)
(https://fbcdn-sphotos-c-a.akamaihd.net/hphotos-ak-prn1/941575_551844648189937_50785268_n.jpg)
^jmwreck : looks awesome !!!
Hi guys,
I tried this design out a few months back and it sounds awesome :)
This is what i ended up with:
(http://i.imgur.com/EbjVloc.jpg)(http://i.imgur.com/G2VXY7s.jpg)
The left hand switch engages a germanium gain stage which pumps a lot of extra power through that valve, creating some very powerful overdrive. I had to spend a long time taming it to an acceptable level :P
The valve I'm using is a vintage Mullard ECC82; adds a nice little bit of jangle.
The circuit took about a week, the case took almost 4 months.. I'm not making a case like that again any time soon!
Just wanted to say thanks for the design!
^^^ That's a cool build. I love the cage over the tube. 8)
Toplak:
I breadboarded the Doublemaster using the schematic you put up on May 10. It worked (almost) on the first try. So I can verify that the Doublemaster schematic is correct. I tried 12AX7 on the first side with 12 volts and it didn't sound good. I was concerned that I had done something wrong but then I read on this thread that 12AX7 tubes don't sound right at less than 18v. That seems to be true. So I finished both sides and put two 12AU7 tubes into it running on 12 volts. I tried it on 9v but it sounds a lot better at 12V. All the pots seem to work and have a noticeable affect on the sound. The tone pots brighten and darken the tone nicely. It seems to get plenty of gain from the A500K pots. I have only tried it on my SS practice amp but the pedal gave it a nice warm tube tone. I am going to play it some more on my good amp, but I really like the way it sounds now.
(http://i1126.photobucket.com/albums/l603/henry7895/IMG_0352.jpg) (http://s1126.photobucket.com/user/henry7895/media/IMG_0352.jpg.html)
(http://i1126.photobucket.com/albums/l603/henry7895/IMG_0346.jpg) (http://s1126.photobucket.com/user/henry7895/media/IMG_0346.jpg.html)
(http://i1126.photobucket.com/albums/l603/henry7895/IMG_0345.jpg) (http://s1126.photobucket.com/user/henry7895/media/IMG_0345.jpg.html)
it comes to mind that perhaps such a design would be perfectly suited to a battery of 6 AA piles (that some other people were talking about doing in a different thread), to provide that 9v and also the Ma Hours.
Regarding the sub-lighting, that's just colored LEDs under the tube right?
Quote from: Henry89789 on June 11, 2013, 07:17:54 PM
It worked (almost) on the first try.
Nice to hear! ^^ Yea, 12AX7s just don't sound right with anything under 18V...
I'm still waiting for my friend to start building the housing for our Valvecaster. Doesn't look like he'll start any time soon though. I'll post some pics and maybe some sound clips when he's (eventually) done.
If all goes according to plan it should look as good as it sounds. :)
Toplak:
Yes, a housing for it is my next problem. What is your friend using as a basis for the housing? A BB size enclosure? Or something else? Thanks.
My friend actually works a lot with metal so we'll be making the enclosure out of 2mm thick sheet metal. And since another friend has access to a laser CNC and has agreed to cut out all the pieces for us for free, that'll save us a heap of time. Then all we have to do is weld the pieces together and drill the holes. If you don't have the experience/funds/tools to make something like this than I'm sure any old metal enclosure would work. Just remember to ground it.
Im buying some russian tubes which are equivalent to this, and also a few pencil tubes, just to play around with the possibilities. :icon_smile:
I've been messing with the valve master again...
Spent a few hours trying to get is perfect and I seem to be getting close... still having some problems with farty mids/bass... I'm not sure if it is simple to much signal or what...
I've got a voltage multiplier that is boosting the volts to around 41. The heaters to plat are being run with 6-ish to pen 9 and both 4 and 5 grounded.
The farts happen when I really dig in while playing... They also will happen regardless of where the volume pot is set... so the problem is before my amp...
I add a passive (Bass/Treble) tone circuit after the second boost section that seems to help rain in the fart-ness a lot. But it is still there...
Should I look at raising the gain to increase compression and maybe box in the flab... or should I be looking at lowering the gain between sections and let the one tube version as more of a booster.
My R2/R3 right now are about 22K to 33K...
Ideas?
Hi, The valve caster is the first pedal that I do. The question is:
When to the valve caster I plug a battery of 9v, it sounds with little level. The valve is illuminated very little.
When I plug a transformer of 9v, the valve caster has much more level. The valve is illuminated more but there is a buzz hummmm.
Since I can solve this?
Thanks to all and sorry for my English!!!!!!!.
Quote from: alexsenmedo on June 29, 2013, 06:56:35 AM
Hi, The valve caster is the first pedal that I do. The question is:
When to the valve caster I plug a battery of 9v, it sounds with little level. The valve is illuminated very little.
When I plug a transformer of 9v, the valve caster has much more level. The valve is illuminated more but there is a buzz hummmm.
Since I can solve this?
Thanks to all and sorry for my English!!!!!!!.
1) The battery maybe dying or low on power.
2) You can solve the 9vDC hiss/hum with proper power filtering.
(http://i73.photobucket.com/albums/i215/Ark-Angel-H-F-B/PowerfilterampPolarityProtection_zps5433fe4d.png) (http://s73.photobucket.com/user/Ark-Angel-H-F-B/media/PowerfilterampPolarityProtection_zps5433fe4d.png.html)
Build the above and connect your 9vDC to it then draw power from the other side. 100uF will also work for C1, but 220uF is better.
If the noise is from a poorly filtered pedal... then this fix will solve your problem... and give you polarity protection at the same time.
^ +1
In additon to a low battery, if your 9V power supply is unregulated, you might be getting 10V to 11V output when connected to he Valvecaster, which would help. If you have a meter, it would be a good idea to check the voltage of the power supply disconnected and connected to the VC. Same for your battery. BTW, due to the current draw of the heaters in the tube, you're going to go through batteries pretty quickly.
If possible, try to find a regulated 12V supply. The 12A_ tubes are designed for 12V across both heaters in series (6V in parallel). The glow is barely noticeable even at 12V, so don't expect much there.
I have a charge pump regulator combo I think I posted a while back in this thread that will give you 32vDC to the plates... and a regulated 6vDC to be connected to pin 9 then just ground pin 4&5.
:'( :'( :'( :'( my thingy didn't work very good, first the tube turned on but without any sound, after that i realized i was wiring th 1M ohm resistor in a bad way , then i modified it and the tube didn't turn on again i dont know if the tube is damaged its an old one that i picked up from an old radio y bought all the parte in steren except the valve and the socket maybe thats the problem can you help me please? im from mexico and here the valves are very expensive
The valve should still be ok... but without picture and voltage reading it is hard to tell...
as far as the valve being bad... idk...
Hi,
I finally finished my valvecaster and it it's great pedal, my previous problem was given by old wires, they get easily broken during manipulation, so I bought new ones and now it works ok.
But I still have one problem, for switching valvecaster off/on, I used simple truebypass foot switch, with 3 connectors, at middle one is going input signal, then in first position it goes through valvecaster circuit and in the second it goes directly to output. Here comes the problem, when it's in the second position, the signal reacts with volume pot, so I can't adjust volume correcly, when it's off, signal is weak and when it's on signal is too strong etc. I'm not sure, but I think it shouldn't be a problem, wires from circuit and from switch going on the same place at output connector. here's the picture of finished stompbox, there's big mess so I'm uploading it just to show connectors and switch. Thanks for the answers. (http://s22.postimg.org/y3kcc1gmp/2013_06_25_17_17_44.jpg)
QuotePosted by: Burdin
Hi,
I finally finished my valvecaster and it it's great pedal, my previous problem was given by old wires, they get easily broken during manipulation, so I bought new ones and now it works ok.
But I still have one problem, for switching valvecaster off/on, I used simple truebypass foot switch, with 3 connectors, at middle one is going input signal, then in first position it goes through valvecaster circuit and in the second it goes directly to output. Here comes the problem, when it's in the second position, the signal reacts with volume pot, so I can't adjust volume correcly, when it's off, signal is weak and when it's on signal is too strong etc. I'm not sure, but I think it shouldn't be a problem, wires from circuit and from switch going on the same place at output connector. here's the picture of finished stompbox, there's big mess so I'm uploading it just to show connectors and switch. Thanks for the answers.
That's 'cause you don't make it true bypass. ;) The out signal is going to the volume pot, actually.
True bypass happends when U use a two position-two throws switch: meanning dpdt. Than, connect the IN side yust as U made it in one side, aaand, the out in the other.
That way, U avoid the out signal goes to the circuit from the back side.
Best regards!!
^^ Take a look at this:
http://www.muzique.com/schem/dpdt.gif
Thank you guys for your help
I finally built a working version of this circuit into a Hammond enclosure. I've also tried some various clipping diodes on the output that make it sound even better.(//)
http://www.aronnelson.com/gallery/main.php/v/Schematics-etc/IMG_20130721_173842_569.jpg.html http://www.aronnelson.com/gallery/main.php/v/Schematics-etc/IMG_20130730_213457_289.jpg.html http://www.aronnelson.com/gallery/main.php/v/Schematics-etc/IMG_20130730_213510_266.jpg.html http://www.aronnelson.com/gallery/main.php/v/Schematics-etc/IMG_20130303_082344_522.jpg.html
I had originally hoped to build the circuit into a cigar box, but I couldn't get it to even barely work...
So the pedal doesn't "crunch" anymore, it only boosts and the gain pot works but is very scratchy. Connecting the box of clippers should cause the signal to get distorted, but there is no change. Anyone have any thoughts of what is wrong? I've tried to locate and solve any physical shorts, but I'm not finding any.
Quote from: Willverine on August 04, 2013, 06:18:40 PM
So the pedal doesn't "crunch" anymore, it only boosts and the gain pot works but is very scratchy. Connecting the box of clippers should cause the signal to get distorted, but there is no change. Anyone have any thoughts of what is wrong? I've tried to locate and solve any physical shorts, but I'm not finding any.
both problems could be caused by lack of gain in one section... ether the tube has gone bad or the pot... or a resistor solder joint is bad... or the law of physicist have change only inside the box...
we won't know till we get some voltages...
Not trying to derail any troubleshooting discussion, but has anyone built a Valvy using a 6J6 tube? It's a dual triode, 7-pin tube...uses about half an amp, has an amplification factor of 38, and the typical plate voltage is running 100V...did I mention they're cheap? ;D
- Larry
Quote from: rutabaga bob on August 05, 2013, 04:37:47 PM
Not trying to derail any troubleshooting discussion, but has anyone built a Valvy using a 6J6 tube? It's a dual triode, 7-pin tube...uses about half an amp, has an amplification factor of 38, and the typical plate voltage is running 100V...did I mention they're cheap? ;D
- Larry
Whaddaya pay for the socket,
and where do ya get the 2nd cathode from???
Quote from: puretube on August 05, 2013, 06:05:40 PM
and where do ya get the 2nd cathode from???
Two cathodes aren't necessary if the cathode is grounded
I usually scavenge sockets from old tube radios, tape recorders, etc., but you can get them from TubeDepot.com or Antique Electronics Supply. The 6J6 only has one cathode. Larry
EDIT: Read today that the 6J6 tends to be noisy and microphonic, but I haven't personally used one yet...maybe use 2 6AT6's or 6AV6's instead? Sorry for interrupting the flow.
For Aussies David Crittle (AKA Critter) from Retrovox is an amazing hand and has some (david@retrovox.com.au) amazingly obscure stuff from time to time, good prices and express post from Wagga Wagga where he's located.
I can't recall if I asked about matching tubes as a service, but at the time of my last order (a while ago now) he was getting over a back injury so was barely able to walk over to his warehouse for me, got great NOS/AnOS 12AU7's.
Quote from: Ark Angel HFB on August 04, 2013, 06:29:32 PM
Quote from: Willverine on August 04, 2013, 06:18:40 PM
So the pedal doesn't "crunch" anymore, it only boosts and the gain pot works but is very scratchy. Connecting the box of clippers should cause the signal to get distorted, but there is no change. Anyone have any thoughts of what is wrong? I've tried to locate and solve any physical shorts, but I'm not finding any.
both problems could be caused by lack of gain in one section... ether the tube has gone bad or the pot... or a resistor solder joint is bad... or the law of physicist have change only inside the box...
we won't know till we get some voltages...
Thanks, I haven't taken the meter to it yet, but I tried both 12AU7 tubes I have and they both didn't produce. I found the same issue with the J&J ECC82 I bought when the 12AU7s worked. I've since turned that tube into a necklace.
Also, love the quote at the bottom of your posts, I had a multi-effect system that picked up a hispanic radio station whenever I used it.
It looks like the wire carrying the filament voltage was shorting out onto the plate of the second stage triode due to poor build quality on my part. Could that damage tubes? I'm still getting the same boosted sound and all the controls behave as they should.
Quote from: Willverine on August 11, 2013, 09:42:42 PM
It looks like the wire carrying the filament voltage was shorting out onto the plate of the second stage triode due to poor build quality on my part. Could that damage tubes? I'm still getting the same boosted sound and all the controls behave as they should.
Tubes are actually quite hardy things, except for the heaters, and those are normally OK as long as you don't burn them out with too much voltage, or damage them with too high of a voltage between the heater and the cathode, which is incredibly unlikely at low voltages like those found in a valvecaster (the 12a*7 series can take 100V or so across the cathode and the heater). So no, you probably haven't damaged the tube.
I put a 12AU7 in my Behringer MIC100 and noticed it sounded less harsh than than the 12AX7. The specs of the AC adapter says the output is 9V 300ma AC (It's actually 12V AC measured with a MM). So can the Valvecaster run on AC voltage instead of DC? Or does it require an entire dofferent circuit?
If you look at the insides of the MIC100 I think you'll find diodes/bridge rectifier near the power supply jack.
This is a bit obsolete but I'll post it anyway for anyone who might be interested:
In the July 2002 issue of Poptronics there was a project called "The Tubester" which was a plate-starved tube preamp. It used a 741 op-amp at the input to boost the guitar signal which was then fed to a 6F5 tube which could be driven to distortion/overdrive (whatever), and then went to another 741 set to unity gain (for impedance matching purposes). It used two 9 Volt batteries for the circuit and 4 C batteries for the heater. The circuit is similar to the one at Valve Wizard's (?) website.
I searched for the article online; the only place I found it required a subscription to see it (assuming they actually had it). If anyone is interested maybe your local library has it archived (university libraries might be a better choice).
Okay, folks...I'm back, after first experiment with the 6J6a. Set it up like a 'Valvemaster'...used .022 input cap, .04 coupling cap, 100k log gain pot, and a 51 ohm cathode rsistor (taken from the datasheet), bypassed with a 10uF cap. Ran 47k plate resistors, but with 79 volts from Adriano's 40106 voltage multiplier. Plugged it into a Kalamazoo Model 1 and tried various gain settings. It definitely works, but will need tweaking - raunchy at max gain, and somewhat bass-y...not bad for a first run, though. As always, any suggestions are appreciated. Larry
After several tweaks, here's what I came up with, if anyone wants to give it a go:
47k plates
.01 input cap
470k to ground
.01 coupling cap
47k grid-stopper
.04 output cap
grounded cathode
500k gain pot
100k volume
construi o meu e funcionou legal. gostaria de saber se alguem tem um esquema de um pre com 12au7 pra 12 volts com som limpo ? obrigado
Desculpe se isso não faz sentido, eu não falo português, mas eu usei o Google Translate ;D. De qualquer forma, há um tempo atrás eu estava brincando com um circuito que dá um som limpo com um tubo 12AT7 em 24V, mas deve funcionar da mesma com uma 12AU7 em 12V. Aqui está o esquema:
(http://s20.postimg.org/5sue8tw7h/Clean_Boost.jpg)
Você pode deixar o resistor 66r e ligar os aquecedores em frente a fonte de alimentação de 12V. Se você só quer um som limpo, em seguida, deixar de fora a chave eo capacitor.
Quote from: Ark Angel HFB on November 08, 2012, 02:57:40 AM
Well as of right now this is were my Valve-Master Project Stands...
Below is not verified...
(http://i73.photobucket.com/albums/i215/Ark-Angel-H-F-B/adsfwwf.png)
Ok things to note...
1. C4/C5 can be left off as it sounds fine without them
2. R4/R5 sound good anywhere from 1k to 0 (they effect gain and volume greatly)
3. R2/R3 sound good anywhere from 1k to 100k (they effect and volume greatly)
4. D1/C6/C7/R6 Form very basic power filtering plus reverse polarity protection. http://www.beavisaudio.com/projects/Huminator/index.htm
5. I leave an extra space after the hook up cables in purpose sp you can drill through the boad there and run the wire through so that the solder joint is never stressed.
6. The Tone Shaper is this http://www.muzique.com/lab/swtc.htm
7. This may come in handy for getting R2/R3/R4/R5/C4/C5 tuned to the correct values... http://www.ampbooks.com/home/amplifier-calculators/cathode-capacitor/
(C4/C5 are each one CK) (R2/R3 are each one RL) (R4/R5 are each one RK)
8. C1/C2 Higher value like 22nF also works but the bass can get out of hand fast...
I hope this helps... the real battle with this pedal will be tuning the amount of volume increase while still preserving the quality of the sound... will have more for you guys later.
I know you've stated that the layout wasn't verified but I've found one issue: there's a cut under R3 that makes the circuit wrong. Otherwise it's ok. I've readyour post as I'm fine tuning my Valvemaster (I've finaly made an enclosure for it) and I'm looking to some succesfull set points. I might change the tone section as I've found it pretty useless.
I've used the standard Valvemaster layout, fed by a stabilized 12,6V power supply (home and custom made). I've changed R2 and R3 by 100k trims and R4 and R5 by 10k trims. Sounded better on breadboard than now (I'll have to double check). Current values are 47k and 510R respectivley for R2/R3 and R4/R5 but I'm not happy with the action of the gain pot: first I get hum/noise, then a cool boost (with no hum/noise) and when I try to get in overdrive region it hums again and doesn't look to have enough gain. On the other hand it can get loud (with volume pot quite high) enough to overdrive my amp if I push it's gain a little bit.
Quote from: psychedelicfish on October 13, 2013, 04:24:07 AM
Desculpe se isso não faz sentido, eu não falo português, mas eu usei o Google Translate ;D. De qualquer forma, há um tempo atrás eu estava brincando com um circuito que dá um som limpo com um tubo 12AT7 em 24V, mas deve funcionar da mesma com uma 12AU7 em 12V. Aqui está o esquema:
(http://s20.postimg.org/5sue8tw7h/Clean_Boost.jpg)
Você pode deixar o resistor 66r e ligar os aquecedores em frente a fonte de alimentação de 12V. Se você só quer um som limpo, em seguida, deixar de fora a chave eo capacitor.
No idea what you are saying, but any reason for using an SRPP?
I was playing around on my breadboard and decided to try it out. It sounded good so I posted a schematic
I built a twincaster and it sounds great for about 5 minutes then it gets splatty. I checked voltages and the only one that's not right is pin 3 of the second tube. I'm getting 3volts on it for some reason.
Quote from: presaa on October 20, 2013, 06:31:58 PM
I built a twincaster and it sounds great for about 5 minutes then it gets splatty. I checked voltages and the only one that's not right is pin 3 of the second tube. I'm getting 3volts on it for some reason.
Make sure you got the resistors going from the tubes grid's to ground (pins 2 and 7).
I still have problems with my Valvemaster.
I've changed the tone section to a super simple solution, though very effective, wiring the cap between the pot wiper and the ground, meaning that I have a variable frequency low pass filter (the simplest variation of Mark Hammer's Stupidly Wonderful Tone Control, with R1=0). It's quite ok rolling off the highs.
No matter the changes I do in the trimpots, I can't get rid of hum. Tweaking the tripots (V+ to anode and cathode to ground resistances) definately changes the gain of the pedal but it doesn't heal the hum problem. Not happy also with the gain pot response but have no ideas about hou to solve it.
Could it be a problem with the tube? I'll change it and test it.
Thanks Kurt I'll check that
If I omit the tone pot, do I also omit C4 on the original schematic? That is just the cap that is part of the r/c tonestack right?
Quote from: timd on November 17, 2013, 02:19:23 PM
If I omit the tone pot, do I also omit C4 on the original schematic? That is just the cap that is part of the r/c tonestack right?
yes
Thanks!
(http://i.imgur.com/tslb85F.jpg)
Said I'd post a pic of the finished thing a while ago but then I forgot... ^^' And now I remembered! Friend still hasn't gotten arround to polishing it but other than that I think it looks pretty good. Working on a modified triple valvemaster circuit at the moment. Will keep you posted if I find anything worth mentioning.
I know there's a million posts on here, so I don't know how actively people still, look, but I need some help. I'm following the original Matsumin schematic for the valve caster with no switch or LED (I tried it with those modifications and it didn't work :P).
When I plug it in and power it on the tube lights up but I don't get any signal. When I turn up the amp volume I get a rather pleasant feedback sound, but the guitar doesn't affect the sound at all. Any thoughts/troubleshooting tips? I'll try to get some pictures posted later so you can get a better look at what I may have done wrong.
I could tell more with pictures, but check that you have no solder shorts and check voltages on pins 1 & 6. They should be between 6 and 9 volts, with 6 a bit higher than 1.
happy tubes to you!
Hi,
I build this effect and it seem that it works, but I have one problem and I would be realy grateful if somone can explain to me, what's goin on.
I'm using this effect for a bass, but I wouldn't say that's the issue. Chain is following: pasive bass -> valvecaster -> lexicon alpha (external PC sound card) -> directly to amplifier (it's not going over the pc), this chain is ok, no problem, everything works fine, but when I use normal amp, in my case it's Trace Elliot GP12 smx here comes problem. Chain is similar, bass-> valvecaster - > trace -> cab, there's almost no change in sound when I turn with any of pots, doesn't react to volume, gain, tone ... nothing, and the result sound it's not plesant, there's feedback from a cab, but when I connect effect to effect loop, it works as it should, why????
I would like to overdrive sound before preamp, it's better for me. So, now I use effect loop, but it's not good. Thank for all answers.
@ psychfush - trick question - can I use a 6J6 (they were cheap here, too) in your srpp circuit?
Is there a list somewhere of all the tubes that work well with the original schematic besides the 12AU7? I had a few random 9 pin tubes around and found a 12DT8 sounds really good in the circuit. I was just looking for something comprehensive to take with me for tube shopping!
Quote from: duck_arse on December 06, 2013, 09:06:05 AM
@ psychfush - trick question - can I use a 6J6 (they were cheap here, too) in your srpp circuit?
6J6 has a common cathode, so you can't do it with one 6J6, but you could use two 6J6s, connecting the triodes in each in parallel.
an interesting idea, but anything taking up that much space would need to be doing a little more work. lord knows, I have enough trouble with "space" as it is.
Quote from: Burdin on December 05, 2013, 06:50:08 PM
Hi,
I build this effect and it seem that it works, but I have one problem and I would be realy grateful if somone can explain to me, what's goin on.
I'm using this effect for a bass, but I wouldn't say that's the issue. Chain is following: pasive bass -> valvecaster -> lexicon alpha (external PC sound card) -> directly to amplifier (it's not going over the pc), this chain is ok, no problem, everything works fine, but when I use normal amp, in my case it's Trace Elliot GP12 smx here comes problem. Chain is similar, bass-> valvecaster - > trace -> cab, there's almost no change in sound when I turn with any of pots, doesn't react to volume, gain, tone ... nothing, and the result sound it's not plesant, there's feedback from a cab, but when I connect effect to effect loop, it works as it should, why????
I would like to overdrive sound before preamp, it's better for me. So, now I use effect loop, but it's not good. Thank for all answers.
You may have something going on with the low or high compression. If you don't have a manual, you might want to take a look at this: http://www.britishaudioservice.com/inst/SMX.PDF
Quick question... How would I go about wiring a twincaster circuit to work with one gain pot?
Stacked pot is one way
Indeed that would be a way... How are amps wired though? Pretty much all amps use only one pot to controll gain for 4+ tubes.
Check out the Pepper Shredder tube boost or Rick Holt's Super Fly or Murder One amps or the Orange Tiny Terror amp schematics.
The gain pot controls how much current flows from the end of the first stage (first half tube) to the second and further stages.
Good luck with which ever path you take.
Thanks mate! I'll be sure to check them out. Love the Tiny Terror btw. Hope I'll have enough money for one soon...
Also, I made this: (http://i.imgur.com/3DA7jpg.png)
Feel free to use this if you need it. The above image is resized. Save it from here: http://i.imgur.com/WqWRnHs.png
It looks huge but it should resize itself to the correct size for printing if you throw it into Word... Let me know if it doesn't.
Very good. Thanks. That should come in handy.
Hello, sorry for my bad English, I'm French.
I have a question, I try to build the Subcaster and I don't know where the middle pin of the trimmer goes. I think it goes to ground but I'm not sure. Can you tell me where this pin is connected ?
Thank you :)
hello and welcome, gamel. yr english is fine so far.
if you mean the trimmer on the lm317 voltage regulator, connect the wiper leg to the grounded leg, so you get a variable resistor.
Hoping for some help. I tried breadboarding a stripped down version (no tone control / 10k fixed gain resistor)
I am getting signal at pins 2 and 3 , but ths signal stops there, no signal at pin 1
I am using 9V, with 100k plate resistors, 470k grid leak resistor, i tried a 12ax7 and 12au7
(http://i40.tinypic.com/2h6fr4l.jpg)
and a schem for easy reference
(http://i39.tinypic.com/14kups9.gif)
I hope I am missing somethig obvious. Cheers
Quote from: bufferz on December 20, 2013, 10:33:31 AM
Hoping for some help. I tried breadboarding a stripped down version (no tone control / 10k fixed gain resistor)
I am getting signal at pins 2 and 3 , but ths signal stops there, no signal at pin 1
I am using 9V, with 100k plate resistors, 470k grid leak resistor, i tried a 12ax7 and 12au7
(http://i40.tinypic.com/2h6fr4l.jpg)
and a schem for easy reference
(http://i39.tinypic.com/14kups9.gif)
I hope I am missing somethig obvious. Cheers
Are you using a battery or adapter? Check your supply voltage.
I am using a "one spot" I suspect it may be a power issue as well. perhaps my breadboard is lowering the voltage ..... I will check it out
Ok, here are the voltages:
P1 -5.2
P2 -7.23
P3 -7.23
P5 9.04
P6 -.63
P7 -.60
fwiw, I tried running it at 12 V using my bbe supercharger and it still didn't work... such a simple circuit - such an epic fail - not a great into to tube circuitry here i'm afraid
Quote from: bufferz on December 20, 2013, 09:33:27 PM
Ok, here are the voltages:
P1 -5.2
P2 -7.23
P3 -7.23
P5 9.04
P6 -.63
P7 -.60
fwiw, I tried running it at 12 V using my bbe supercharger and it still didn't work... such a simple circuit - such an epic fail - not a great into to tube circuitry here i'm afraid
Are the voltages at pins 1, 2, 3, 6, and 7 negative relative to ground?
sorry - not sure what you mean exactly, to gather the voltages i referenced above I put the positive tip of the muiltimeter to the respective pin and negative to ground
Quote from: bufferz on December 20, 2013, 10:33:03 PM
to gather the voltages i referenced above I put the positive tip of the muiltimeter to the respective pin and negative to ground
So no, the voltages you measured were not negative relative to ground. Just a tip: a dash next to a number makes it look like that number is supposed to be negative.
Quote from: bufferz on December 20, 2013, 09:33:27 PM
Ok, here are the voltages:
P1 5.2
P2 7.23
P3 7.23
P5 9.04
P6 0.63
P7 0.60
[edited: removed dashes and added leading zeros -jdansti]
fwiw, I tried running it at 12 V using my bbe supercharger and it still didn't work... such a simple circuit - such an epic fail - not a great into to tube circuitry here i'm afraid
Probably a solder bridge, bad joint, or miswiring. It happens on the simplest of builds.
Does anyone know if the voltages above look correct for a 9V supply?
Quote from: Jdansti on December 21, 2013, 02:09:44 AM
Does anyone know if the voltages above look correct for a 9V supply?
Heck no. Pin 1 should be higher in voltage than pin 2 and 3. Pin 2 should be at 0V, pin 3 should be slightly higher than ground, no more than 1V. Pin 6 should be way higher than it is, pin 7 might be alright.
Are you sure you've got the pins wired right? With the gap facing you and the valve upside down, pin one is on the left hand side of the gap and the pins are numbered clockwise from there. Are your valves getting warm?
Also, just a note, the valve caster will work better on 12V, the filaments are designed for 12V and the characteristics of the valve will change dramatically with the filament voltage.
Thanks for your responses.
I did double check the wiring and the valve is getting warm (if i turn the lights off i can see the glow)
for some reason i have signal at pins 2 and 3 but the signal never goes to pin 1, that's where it stops.
i did try 12v as well.
got it resolved, was a bad solder joint on socket. :icon_redface: Thanks your patience and advice
Glad you got it working, 90% of the time it's something like that :icon_biggrin:.
Man, it took me longer to read this whole thread than it did to build one of these Valvecasters, off the original Bevis layout. I am wondering if it is safe to run it on a regulated 18V laptop supply I have, or safer to regulate a line off to 12V? Really sounds nice on 9V. Such great work I have seen here! Can't post a pic yet from this computer, but I will soon. :icon_mrgreen:
You want to keep the heaters at 12V in series (or 6V parallel). The rest of the circuit can be 18V.
To get 12V across the heaters, put them in series with a 33 ohm, 1W resistor.
Hey guys. I need some help... Wasn't the idea behind the valvemaster gain pot wiring to eliminate scratching sounds when turning? Somehow my circuit sounds more scratchy than with the original circuit... Any ideas why? Pots are not ALPHA but they are pretty high quality.
Also, I have two more problems with this circuit. (triple valvemaster by the way) First tube on it's own sounds nice but there is a high pitched hissing sound to be heard that I cant seem to figure out where it's coming from. First + second stage sound fine. All stages together sound farty however... Sounds nice when the input signal is high like when you've just strummed a chord, but when the signal gets weaker, like when a note starts dying out, then the sound gets farty...
Changed the cathode capacitors from 10uF to .1uF. Plate resistors for the first stage are 47k, second and third stage have 150k. (all plate resistor are socketed so I can easily swap them if needed) Pedal is powered by an extremely well regulated 24V 1.4A toroid. Regulated 12.6V for heaters and regulated 20V for everything else. Pin voltages check out as far as I can tell...
Any help would be grately appreciated!
Happy tubing
toplak666 - can you post the schematic you're working from?
Basically this:
(http://i.imgur.com/Rnxj11X.jpg)
But without the tone circuit and not at 9V but 20V. I use relays and 3PDTs for switching between stages. The switching circuit is huge but it's mostly bussing.
So I fixed the tube 1 problem. Turns out the plate resistors I selected were too high... I'll experiment with different values in the future but for now I'll keep them at 47k. Tube 3 is still an issue though. The sound is fine with a high input signal but when the signal starts to decay the sound gets farty and quite quickly after that dies out.
Any ideas?
Is your input and output jack negative connection grounded? I had similar problem and noticed only the positive (tip) was connected to the ckt.
Checked. Both are indeed grounded. Dont have a housing yet though... Hopefully I'll have it by the end of next week.
Hi, I'm a noob in this forum, I was wondering if this can be build using 6922/6dj8 since i had a couple, perhaps with different value of resistors and/or capacitor but keep the 9v power supply?
Try it with stock values (except for the valve) and if it sounds bad, post a description (or even better, a recording) of how it sounds. We should be able to make some suggestions from there.
I'll have it done by the end of the day! :)
To all valvecaster builders.. was wondering if you guys ever run the tube at high plate voltage ie 350VDC?
Quote from: hopkinWFG on January 12, 2014, 08:12:52 AM
To all valvecaster builders.. was wondering if you guys ever run the tube at high plate voltage ie 350VDC?
I've never tried it, as the 12AU7 doesn't require that much voltage to "sound like a tube." If you were going to try it with a 12AX7 then you would need at least 300V across the plates to make it sound like a 12AX7, which would also give you more gain. This can be a desirable thing depending on the sound you're going for.
I've built the original Valve Caster and the Twincaster, which are both great at what they do, but I'm also working on this pedal that uses around 300V on a pair of 12AX7s and has a lot more gain than the Valve Caster series.
http://www.diystompboxes.com/smfforum/index.php?topic=93936.0
Check it out :)
Quote from: toplak666 on January 11, 2014, 04:32:00 PM
Checked. Both are indeed grounded. Dont have a housing yet though... Hopefully I'll have it by the end of next week.
Anytime you make a circuit like this and it starts to become Hi gain you you will get parasitic oscillations etc. Sheilded wire helps a ton.Good layout and a grounded enclosure also helps a ton. Also, tubes run at low voltage will start to get dc on the grids when pushed into clipping. put a capacitor on the input pins ( 2, 7 ) Thats what c1 does on the original schematic otherwise your guitar volume would be scratchy. make sure you put the grid leak resistor after the cap like the example of c1 on the original. Also putting small value caps from plate to ground to bleed of some of the extreme high end will help. I wouldnt do it on stage 1 but on stage two and three it helps a lot. Using small grid caps helps tame some of the farty sounds as well. When you run tubes in space charge they develop a lot of bass and a lot oh high end which is nice on a single tube. makes that warm tubey break up. cascade it through 6 stages and you get to many highs and to much bass amplified and reamplified. starts making weird feed back. that will cause signal to die out like that as well. by using smaller coupling caps ( .001 or .002 ) in the 3,4,5,6 stages you cut out some of the farty bass. bleeding off the extreme highs from the plates on the same stages leaves behind a signal thats been boosted in the mids a lot. I built one of the first ( maybe the first? ) triple valve caster and built several more versions of it experimenting as I went. This is what I learned along the way. Hope it helps and good luck!!
Quote from: zambo on January 28, 2014, 01:16:54 PM
Quote from: toplak666 on January 11, 2014, 04:32:00 PM
Checked. Both are indeed grounded. Dont have a housing yet though... Hopefully I'll have it by the end of next week.
Anytime you make a circuit like this and it starts to become Hi gain you you will get parasitic oscillations etc. Sheilded wire helps a ton.Good layout and a grounded enclosure also helps a ton. Also, tubes run at low voltage will start to get dc on the grids when pushed into clipping. put a capacitor on the input pins ( 2, 7 ) Thats what c1 does on the original schematic otherwise your guitar volume would be scratchy. make sure you put the grid leak resistor after the cap like the example of c1 on the original. Also putting small value caps from plate to ground to bleed of some of the extreme high end will help. I wouldnt do it on stage 1 but on stage two and three it helps a lot. Using small grid caps helps tame some of the farty sounds as well. When you run tubes in space charge they develop a lot of bass and a lot oh high end which is nice on a single tube. makes that warm tubey break up. cascade it through 6 stages and you get to many highs and to much bass amplified and reamplified. starts making weird feed back. that will cause signal to die out like that as well. by using smaller coupling caps ( .001 or .002 ) in the 3,4,5,6 stages you cut out some of the farty bass. bleeding off the extreme highs from the plates on the same stages leaves behind a signal thats been boosted in the mids a lot. I built one of the first ( maybe the first? ) triple valve caster and built several more versions of it experimenting as I went. This is what I learned along the way. Hope it helps and good luck!!
Wow man, thanks! That sounds like a lot of good information that I would surely not have thought of by myself. I'll try each and every one of these as soon as possible and post the results :)
Glad to help :) here is one thats been built like that and running at 30 or 40 volts on the plates. http://www.youtube.com/watch?v=YhyyYjY5CgA
Quote from: zambo on January 28, 2014, 05:11:26 PM
Glad to help :) here is one thats been built like that and running at 30 or 40 volts on the plates. http://www.youtube.com/watch?v=YhyyYjY5CgA
Perfect. That's pretty much exactly the sound I'm going for. I'll get on it later today!
Hi all, first post! I've breadboarded one of these, totally new to diy though, so it works, but I don't know why yet. I've got an old mA meter, is it possible to wire it so it shows the effect on bias of turning the gain pot? As I say, new to all this so any help would be appreciated!
welcome! Not sure what you would measure other than current going through the tube. As you turn the gain put up or down more or less current should be flowing. try putting your meter in series from pin 3 to ground or use a 1 0hm 1 percent resistor in series ( before the gain pot ) and measure the millivolts across it. The closer the gain pot gets to 0 resistance the more current flows. I think i got that right anyway.. :icon_redface: Current flows from anode to cathode and the grid in between acts like the valve gate restricting or accelerating that flow. the grid is your ac guitar signal. this causes the voltage of the plate to fluctuate in time with your guitar signal but at a much higher voltage. that is where you get signal amplification. the coupling cap to the next grid blocks the dc voltage and lets the larger ac signal through where it goes through the same process. Does that make sense? along the way the signal clips and developes harmonics etc. that also get amplified. thats where you get that tubey goodness. Kind of over simplified but thats my understanding of tubes in general terms.
Quote from: zambo on January 28, 2014, 05:11:26 PM
Glad to help :) here is one thats been built like that and running at 30 or 40 volts on the plates. http://www.youtube.com/watch?v=YhyyYjY5CgA
Zambo dude if you were here right now I'd kiss you! Those tips you gave me not only removed all the farty and scratchy sounds but it really did boost the mids just like you said! The caps in the last stage still need some tweeking to get the perfect sound but that's a job for when I get the housing. Funny thing is that even though my circuit is built on a custom designed pcb I had no problems adding those caps and resistors. I'll post some pics soon. I think this build looks quite nice. :)
So thanks again! I owe you a beer!
Awe shucks ... just glad I could help! I do like beer though so if you get to napa anytime, look me up :icon_smile: You should see all the weird tube stuff hanging around in my garage hahaha!
Thanks zambo, will try that!
Finally got arround to uploading these images:
Power supply:
(http://i.imgur.com/WPwAov7.jpg)
Yes, that 40mm fan is necessary. The 2 voltage regulators I'm using actually fry after a minute without the fan. They run pretty cool with the fan and it's actually quiet enough to the point where it probably wouldn't be picked up in a studio.
Switching circuit - top:
(http://i.imgur.com/bJ7LfDn.jpg)
5V voltage regulator, 2 relays and 3 footswitches.
Switching circuit - bottom:
(http://i.imgur.com/xSpvpFg.jpg)
Looks complicated but it's mainly just bussing...
Main circuit - top:
(http://i.imgur.com/33Bagfo.jpg)
Not much to say here...
Main circuit - bottom:
(http://i.imgur.com/tFtiLGh.jpg)
Basically the same layout copied 3 times. I think it looks pretty cool.
You have to excuse any bad or messy solder joints you spot. My cheapo soldering station broke and I was forced to use a huge old soldering iron. Got a brand new soldering and smd rework station now.
Enclosure should look pretty nice too. I'll post another update once I get it. :)
Higher resolution images:
http://i.imgur.com/t79KBfE.jpg
http://i.imgur.com/Crb6lEm.jpg
http://i.imgur.com/VPJcQxh.jpg
http://i.imgur.com/rKPtI6K.jpg
http://i.imgur.com/eyTzhLu.jpg
^Very nice!
Do you have any problems with the fan causing noise in the system?
Quote from: Jdansti on February 10, 2014, 09:15:00 PM
Do you have any problems with the fan causing noise in the system?
I had quite a bit of problems with that because at first I was using a lm78l08 Connected to the 12.6V rail to power the fan which was causing quite a bit of interference. I then started experimenting with 1 and 2 transistor constant current source circuits (still on the 12.6V rail) but if anything that somehow managed to make more noise... I then moved the ccs in front of the 2 regulators (so 25V, directly after the rectifier) and now it's not causing any noise whatsoever and it's keeping my regulators nice and cool! :)
I'll remember that if I ever have to use a fan. Thanks!
Here's pics of my valve caster builds...
(http://i392.photobucket.com/albums/pp8/XxdaverocksxX/a97d8e64-4c48-4532-b9df-543e572ac951.jpg)
(http://i392.photobucket.com/albums/pp8/XxdaverocksxX/23e7f05b-0b26-4506-973b-cce847d39b97.jpg)
Hammond 1590B - 60's Canadian RCA 12AU7
No mods from the Beavis layout - 9V.
.......................................................................
(http://i392.photobucket.com/albums/pp8/XxdaverocksxX/872f2b48-8818-4c4b-9e1a-379a0e50353c.jpg)
Hammond 1590BB - New, Groove Tube 12AU7's -Nice/Good sounding tubes.
The circuit is on perf board. The perf board has two 7/8" holes drilled into it - to mount the tube sockets.
I used Renegadrian twin tube vero layout.
Smooth drive but gets noisy when you aren't playing.
9V. or 12V.
...
(http://i392.photobucket.com/albums/pp8/XxdaverocksxX/15c0bd46-78cd-412b-81d9-75c2be8f0adc.jpg)
The top of the enclosure is made from a steel serving tray, bought from a thrift store - 2bucks.
The box is shielded inside and made of wood & covered in brown tolex.
The circuit is on perf board. The perf board has two 7/8" holes drilled into it - to mount the tube sockets.
I used Renegadrian twin tube vero layout.
Two new 12AU7 Chinese Tubes.
The new Chinese tubes when you look at them close
you can see the plate and cage aren't as robust as the old tubes.
The new tubes are harsher in sound.
Gets noisy when you aren't playing.
9V. or 12V.
...
(http://i392.photobucket.com/albums/pp8/XxdaverocksxX/debe5481-6b36-4211-87d7-bf972fdfd313.jpg)
60's SYLVANIA 12AU7
The enclosure is some kind of electrical break out box made by Square D
It is solid steel and was very hard to drill.
But this valvecaster is VERY quiet.
No mods from the Beavis layout - 9V.
...
(http://i392.photobucket.com/albums/pp8/XxdaverocksxX/22151165-1562-45ee-973f-b3119481b436.jpg)
60's Canadian RCA 12AU7
The enclosure is some kind of electrical break out box made by Square D.
Thin steel , easy to drill.
Stands tall and stable on it's leg fins. Good creamy/cruncy sound.
...
This Valve Caster I sold - it has a ColorSound One Knob Fuzz housed with it.
(http://grantone.8k.com/12AU7B.jpg)
(http://grantone.8k.com/Grantone12AU7.jpg)
Hi all, I asked a few posts ago if I could add an analogue mA meter into this. I've tried everything, in series like suggested, to every pin, and any other way I could think of. I can't get a reading at all. I want to be able to see on the mA meter the effect of turning the gain. Is the current too small to be read by a 1mA meter, or am I just missing something? Would really appreciate any help!!
did you try to put a 1ohm 1 percent resistor in series with the gain (bias) pot and measure across it in mv which will be the same as ma if i am not mistaken. thats how you measure the ma in a tube amp. kinda the same principal.
Hi Zambo, yeah I've tried that, tried it in series before and after the pot, still couldn't get any reading. Does the gain pot alter the amount of current going to pin 8 to being the other cathode? Really bugging me that I can't figure this out!!
yeah thats weird. you should be able to read something. current might be to small to read. both cathodes should be flowing current. they are separate so they should give separate readings. I guess you could use ohms law to calculate how much current should be flowing so you have something to kinda aim for. I will see if I can do it tonight. I have one on my bench right now.
Cheers Zambo, let me know if you get it going!
capes - does your meter have "1mA dc fsd", or "mA _" and numbered "0" to "1" or something similar printed on the scale? and does it have some other current or voltage marking on the back of the meter case? very often, a meter with a full scale deflection of 1mA was fitted with a shunt resister to change the voltage or current read, without changing the meter dial.
you'll probably need to googoo "moving coil meter calibration" or similar, to see the method.
It's this one..
http://www.electricalmate.co.uk/proddetail.php?prod=Monacor-PM-2%2F1MA-Moving-Coil-Panel-Meter&gclid=CNbt44eM_rwCFSUUwwodqU4ASQ
And I've just seen it's internal resistance in 200. Balls. Is there anyway I can just take that shunt out and replace it with a 1ohm? I couldn't get a reading on my mm either, on the output pot it was showing, but not on the gain. I'll have a look at moving coil meter calibration now, thanks for your help mate.
ahh, no need for balls. that 200R is the exact number you will need to plug the equation. you're nearly there.
I found this, which explains the resistances etc...
http://sound.westhost.com/articles/meters.htm
But I still don't understand why I'm not getting a reading? Am I just placing the meter in the wrong place? Surely if I just placed the meter in with no additional resistor, then the needle would fly up? Sorry if I'm missing something stupidly obvious, still trying to wrap my head around all of this!!
tell me again, exactly what current, and where, are you wanting to measure/indicate?
I'm want the meter to show the effect of turning the gain pot, on pin 3. Which I think is the bias??
(http://www.beavisaudio.com/Projects/ValveCaster/MatsuminValveCaster.gif)
in this circuit? I'm not the person to ask about valve currents. however, if you have a dmm, it will measure whatever is there to measure, within reason. you need to insert the meter set to (milli)amps dc in series with either R2 or VR1.
the same applies for the moving coil meter. if you have calculated your shunt resistance (if it is needed), it goes across the meter terminals, and then in series with that which you want to measure.
Quote from: duck_arse on March 06, 2014, 11:44:11 AM
(http://www.beavisaudio.com/Projects/ValveCaster/MatsuminValveCaster.gif)
in this circuit? I'm not the person to ask about valve currents. however, if you have a dmm, it will measure whatever is there to measure, within reason. you need to insert the meter set to (milli)amps dc in series with either R2 or VR1.
the same applies for the moving coil meter. if you have calculated your shunt resistance (if it is needed), it goes across the meter terminals, and then in series with that which you want to measure.
Excellentely put. Measuring current is different than measuring voltage or resistance because voltage and resistance can be measured with the leads in parallel to the circuit, whereas current
MUST be measured with the leads in series.
Quote from: duck_arse on March 06, 2014, 11:44:11 AM
(http://www.beavisaudio.com/Projects/ValveCaster/MatsuminValveCaster.gif)
in this circuit? I'm not the person to ask about valve currents. however, if you have a dmm, it will measure whatever is there to measure, within reason. you need to insert the meter set to (milli)amps dc in series with either R2 or VR1.
the same applies for the moving coil meter. if you have calculated your shunt resistance (if it is needed), it goes across the meter terminals, and then in series with that which you want to measure.
Yeah, that's the one, except for a few cap changes and 60V and 6V to the heaters on pin 5. I tried with my dmm on R2, it gives a reading over the resistor, but then when I put the meter in, the circuit still works, but no reading. Pretty annoying. The dmm is responding to changes on the gain pot too. Scratching my head doesn't come close at the min! Will try and crack it tonight. Thanks again for your help..
Quote from: vigilante397 on March 06, 2014, 01:30:46 PM
Excellentely put. Measuring current is different than measuring voltage or resistance because voltage and resistance can be measured with the leads in parallel to the circuit, whereas current MUST be measured with the leads in series.
Hi mate, I've been placing it in series, pretty sure I'm doing it right. Any chance you could explain how you'd go about it?
Quote from: capes83 on March 06, 2014, 02:16:31 PM
Hi mate, I've been placing it in series, pretty sure I'm doing it right. Any chance you could explain how you'd go about it?
Measuring in series can be tricky because it usually means you have to take apart your circuit. The current needs to be flowing through the DMM, not just across it. I drew some diagrams to make it more clear because I'm terrible at explaining :P
Excuse the crude artwork; I'm on my work computer and the only graphics software I have is Paint :P
Parallel measuring (i.e. for measuring resistance, voltage, etc.) - https://www.dropbox.com/s/ibq3degnyn9ttxl/parallel.JPG
Series measuring (i.e. for measuring current) - https://www.dropbox.com/s/crmqtlcjgl9sh0c/series.JPG
Hope this helps :)
Yeah, that's what I've been doing. Can't seem to get it working. Where abouts on the schematic would you put it? I've tried it before and after R2, and before and after the gain pot. Do you think the current is just too small to read? Weirdly, if I place my digital meter over the resistor at R2, so in parallel, it works. My brain hurts.
What are you measuring with the DMM?
It's set to read mA.
someone on this forum said it was not enuff to know ohms law, but to know when to apply it. or something similar.
and always is the time to apply it, but it never seems to occur to me till the next day. gets yr dmm, measure yr volts dc at the top of R2, the supply voltage. measure the voltage at the other end of same resistor, the anode/plate voltage. subtract the smaller number from the larger, and divide by the resistance. this will give you the current into the valve. if it is more than 1mA, you'll need to re-shunt yr moving coil meter. if it is less than 1mA, you'd expect the needle to move by one 0.1 marking on the meter for each 100uA. less than 100uA, and you'll probably need a meter amp.
with no signal, turn the gain pot while measuring the plate voltage. does it change? by how much? put the highest and lowest # you get through the resistor calc, and that's your current. seeing as the second stage is ac connected, it won't draw any dc current from the first stage, so what goes in at the top will also dribble out the bottom.
you can prove this by measuring the kathode voltage as you vary the gain pot, and work the I=V/R there too. don't divide by nought, tho.
so i've read about 30 pages so far and i really want to start on this. i play through an active bass though. can i change a couple things in the circuit or do i need to run something in front of it to lower the input signal?
Quote from: froglicker on March 29, 2014, 02:40:22 AM
so i've read about 30 pages so far and i really want to start on this. i play through an active bass though. can i change a couple things in the circuit or do i need to run something in front of it to lower the input signal?
I've never had any problems with active pickups through this one. You would definitely want to change the input and output capacitors to higher values so they don't filter out the low end of your bass.
alright thanks. will do. i just figured somethings would need to be changed because of past experiences with boosts and od's.
hey all, Im new to this site. Thank you DIYstompboxes for accepting my registration: I ended up at this forum while searching ways to build a guitar boost circuit using one tube. I know there are probably tons already built and/or written to choose from both commercially and diy's but i'm kinda particular about it and like the idea of gaining experience in this sort of build because i have other ideas for projects in my head and down on paper that i would like to accomplish and it's remarkable how close this discussion is to being exactly what i was looking for. I think as a starter i will take on this particular 12au7 boost project first and then maybe see what can be done when using 18v rather than 9v ...maybe the added headroom will be a little closer a range supportable for a 12ax7, at least it will bring the middle of voltage sweep to a solid 9vdc rather than 4.5 which might not be too bad. Is this idea totally lame or ??.. any thoughts ideas? Somewhat familure with dual triode preamps but don't know this circuit at all as i've yet to even see how its possible to heat, bias & output an 12au7 with 9vdc?!?! Thanks for any input
Quote from: dynotouch on April 06, 2014, 03:38:44 PM
hey all, Im new to this site. Thank you DIYstompboxes for accepting my registration: I ended up at this forum while searching ways to build a guitar boost circuit using one tube. I know there are probably tons already built and/or written to choose from both commercially and diy's but i'm kinda particular about it and like the idea of gaining experience in this sort of build because i have other ideas for projects in my head and down on paper that i would like to accomplish and it's remarkable how close this discussion is to being exactly what i was looking for. I think as a starter i will take on this particular 12au7 boost project first and then maybe see what can be done when using 18v rather than 9v ...maybe the added headroom will be a little closer a range supportable for a 12ax7, at least it will bring the middle of voltage sweep to a solid 9vdc rather than 4.5 which might not be too bad. Is this idea totally lame or ??.. any thoughts ideas? Somewhat familure with dual triode preamps but don't know this circuit at all as i've yet to even see how its possible to heat, bias & output an 12au7 with 9vdc?!?! Thanks for any input
First of all, welcome :) This was my very first DIY build, and i think it's a very good introduction to building.
Second, I never run tube pedals on anything less than 12V. I've also found that the lower the current rating of a power supply the noisier it is. I first tried it with 9v 300mA and it was dreadful, so I used 12v 300mA and it was better, but I ended up settling on a 12v 1000mA power supply, and it runs amazingly. I have heard a lot of people say they prefer it with an 18v supply for the headroom just as you mentioned.
Welcome again and good luck :)
^Just a reminder to keep the heaters at 12V in series or 6V in parallel.
Quote from: Jdansti on April 06, 2014, 08:41:37 PM
^Just a reminder to keep the heaters at 12V in series or 6V in parallel.
+1 ;D
First of all, welcome :) This was my very first DIY build, and i think it's a very good introduction to building.
Second, I never run tube pedals on anything less than 12V. I've also found that the lower the current rating of a power supply the noisier it is. I first tried it with 9v 300mA and it was dreadful, so I used 12v 300mA and it was better, but I ended up settling on a 12v 1000mA power supply, and it runs amazingly. I have heard a lot of people say they prefer it with an 18v supply for the headroom just as you mentioned.
Welcome again and good luck :)
[/quote]
awesome... thanks for those tips. i need to go back and just read thru the entire thread still, i think it'll be quite useful to take in the entire discussions and all that it has to offer. I just read the first few pages and then kinda went hog wild thru my e-junk seeing what i had laying around. think i have most of what's needed to mock up a test & tweak board like resistors and old amp chassis with 9 pin sockets, but I'll need to go out and get the needed caps and a 12au7 (all i have is 12ax's) or get them from someone here(??) I'll keep posting here as i progress ..thanks!
Quote from: Jdansti on April 06, 2014, 08:41:37 PM
^Just a reminder to keep the heaters at 12V in series or 6V in parallel.
Thanks! ...how about 9vdc in series/parallel ;)
I've never tried 9V on the heaters. The tube really is designed to be run on 12V in series (6V parallel), although some people have used 9V in series. Maybe someone who's done that will chime in on the performance.
You could use 9V and drop the voltage to 6V using a regulator and wire the heaters in parallel. Alternately, I'm not sure if a resistive voltage divider is a good idea on this circuit to get 6V from 9V. Maybe someone who knows more than I could answer that.
If you decide to go above 12V on the plates, stay within the voltage limits for the heaters by dropping the voltage going to them.
Quote from: Jdansti on April 07, 2014, 02:31:15 PM
I've never tried 9V on the heaters. The tube really is designed to be run on 12V in series (6V parallel), although some people have used 9V in series. Maybe someone who's done that will chime in on the performance.
You could use 9V and drop the voltage to 6V using a regulator and wire the heaters in parallel. Alternately, I'm not sure if a resistive voltage divider is a good idea on this circuit to get 6V from 9V. Maybe someone who knows more than I could answer that.
If you decide to go above 12V on the plates, stay within the voltage limits for the heaters by dropping the voltage going to them.
Cool, yeah i wouldn't attempt to exceed 12v either on the heaters(or 6.3 in parallel). going by the diagram and scheme provided here by a member and it must be parallel and the heaters are getting 6vdc...no??
There are a lot of schematics on this thread. :) The original one on page 1 uses 9V on the heaters in series (through pins 4 and 5). If you want the full effect that the heaters can provide and still use a 9V PSU, then use 9V as shown in the schematic, except you would add an LM7806 regulator to get 6V just for the heaters. Positive 6V to pins 4 and 5 and ground pin 9.
I can draw it out when I have more time this evening if you need it. Maybe someone who knows of an existing schematic or layout will chime in before then.
I think it would be better to find a 12V PSU, add a little filtering to the power if necessary, and run the whole thing on 12V using the original schematic.
Let me know if you need a drawing for using 9V.
Quote from: Jdansti on April 08, 2014, 02:29:28 PM
There are a lot of schematics on this thread. :) The original one on page 1 uses 9V on the heaters in series (through pins 4 and 5). If you want the full effect that the heaters can provide and still use a 9V PSU, then use 9V as shown in the schematic, except you would add an LM7806 regulator to get 6V just for the heaters. Positive 6V to pins 4 and 5 and ground pin 9.
I can draw it out when I have more time this evening if you need it. Maybe someone who knows of an existing schematic or layout will chime in before then.
I think it would be better to find a 12V PSU, add a little filtering to the power if necessary, and run the whole thing on 12V using the original schematic.
Let me know if you need a drawing for using 9V.
think ill just stick to the original design that dano12 provided in the beginning of the thread and go from there. actually, I'm almost done just need to inspect and wait for the tube with i ordered and should be here any day. i'll report! thnxQ
Sounds good. Let us know how it turns out!
It's purdy much built but not working yet(??). didn't have a 12au7 to test with so i tried a 12ax and got nothing at all and vdc from a battery dropped to about 5.3v when measured from the plates and the heaters were only getting something like 3v or visa-versa so i'm not doing something right (besides the obvious of trying the 12ax7). also i have the physical circuit spread out over a 8"x 6" board so i wonder of thats too big for such low current and voltage?? waiting on a 12au7 in the mail and need to find filtered and regulated 9vdc psu(has anyone here aver built a pedal apt supply... is there another thread dealing with that kind of build??) ....I'll go back over my work and report. thanks!
Btw: (i'll be simultaneously starting an component upgrade & mod project to my vintage ibanez cs9 st chorus pedal and searching for input and suggestions about that on another thread somewhere more subject orientated as such)
Try a fresh 9V battery. Most people use a wall wart because the heaters will run a battery down pretty quick.
Quote from: dynotouch on April 12, 2014, 01:36:16 PM
It's purdy much built but not working yet(??). didn't have a 12au7 to test with so i tried a 12ax and got nothing at all and vdc from a battery dropped to about 5.3v when measured from the plates and the heaters were only getting something like 3v or visa-versa so i'm not doing something right (besides the obvious of trying the 12ax7). also i have the physical circuit spread out over a 8"x 6" board so i wonder of thats too big for such low current and voltage?? waiting on a 12au7 in the mail and need to find filtered and regulated 9vdc psu(has anyone here aver built a pedal apt supply... is there another thread dealing with that kind of build??) ....I'll go back over my work and report. thanks!
Btw: (i'll be simultaneously starting an component upgrade & mod project to my vintage ibanez cs9 st chorus pedal and searching for input and suggestions about that on another thread somewhere more subject orientated as such)
12ax7 doesnt always work in this design. Cant remember why. to much plate resistance or something. at7 same thing. Some do work, but its hit and miss. 12au7 works consistently. you probably built it right.
Quote from: toplak666 on May 10, 2013, 01:00:07 PM
(http://i.imgur.com/ZWMg0SC.jpg)
There ya' have it. Ain't she a beaut? ;) With this design you should be able to get nice crunch tones from the first stage and great drive sounds from the second stage.
This should work with all 12A_7 tubes, but keep in mind that while other tubes should work with plate voltages above 9v, 12AX7s need at least 18v for the plates. They just don't sound right otherwise... I can't say for sure but I suspect 12AT7s would require 18v too.
The first volume pot is completely optional but I recommend leaving it in. You can get more sounds by fiddling with it while using both stages.
This is ment to be used with two true bypass circuits. One for the first stage and one for the second. Didn't bother putting those in the schematic because I figured if you can wire up this circuit you should be able to wire in a bypass...
You diystompboxes veterans are welcome to fix any mistakes in the schematic. I'm still pretty new to tube circuits... :)
Does the doublemaster schematic work? I am thinking about building it. If it does work, are the 12v and 18v working at the same time? Where would I put two 3dbt switches. I understand most of the schematic, I just don't know where to insert things.
hello and welcome to the forum, van.
the heater current at 12V for a 12a_7 valve is 150mA. you have two valves, so you need a minimum heater current of 300mA. if you get yourself a good, clean 18V supply, at least 400mA rated, you can then use a 12V three terminal regulator on a nice big heatsink for the heaters, and power the whole mess, no fuss.
as for if it works, it might be too much gain to be stable, I don't know. you can only try it. as for switches, you'd have to decide what setup you wanted and which sections you want switched.
Quote from: Vanwilliams on April 18, 2014, 09:21:51 AM
Does the doublemaster schematic work? I am thinking about building it. If it does work, are the 12v and 18v working at the same time? Where would I put two 3dbt switches. I understand most of the schematic, I just don't know where to insert things.
As long as you keep the plate voltage 18V or higher it should work nicely. You might notice that it has a bit (or a lot) too much bass. In that case you should make these modifications:
Quote from: zambo on January 28, 2014, 01:16:54 PM
Anytime you make a circuit like this and it starts to become Hi gain you you will get parasitic oscillations etc. Sheilded wire helps a ton.Good layout and a grounded enclosure also helps a ton. Also, tubes run at low voltage will start to get dc on the grids when pushed into clipping. put a capacitor on the input pins ( 2, 7 ) Thats what c1 does on the original schematic otherwise your guitar volume would be scratchy. make sure you put the grid leak resistor after the cap like the example of c1 on the original. Also putting small value caps from plate to ground to bleed of some of the extreme high end will help. I wouldnt do it on stage 1 but on stage two and three it helps a lot. Using small grid caps helps tame some of the farty sounds as well. When you run tubes in space charge they develop a lot of bass and a lot oh high end which is nice on a single tube. makes that warm tubey break up. cascade it through 6 stages and you get to many highs and to much bass amplified and reamplified. starts making weird feed back. that will cause signal to die out like that as well. by using smaller coupling caps ( .001 or .002 ) in the 3,4,5,6 stages you cut out some of the farty bass. bleeding off the extreme highs from the plates on the same stages leaves behind a signal thats been boosted in the mids a lot. I built one of the first ( maybe the first? ) triple valve caster and built several more versions of it experimenting as I went. This is what I learned along the way. Hope it helps and good luck!!
Oh, and omit the two tone controll pots... They are pretty useless.
toplak - regarding the useless tone controls, have you tried the swtc config, like so?
(http://www.muzique.com/images/swtc1.gif)
amz has a bunch a stuff on this style control here:
http://www.muzique.com/lab/swtc.htm
Hey duck_arse, what if I used 12au7 tubes instead of12ax7's? Could I then power it using 9v and have a problem with gain? Or if I did 50/50 on the two tubes and had two modes: 1 would be 12au7 and 12ax7, and the second would also have a 12au7 and 12ax7, so then I have less gain, but still some bite?
Quote from: duck_arse on April 20, 2014, 11:44:00 AM
toplak - regarding the useless tone controls, have you tried the swtc config, like so?
(http://www.muzique.com/images/swtc1.gif)
amz has a bunch a stuff on this style control here:
http://www.muzique.com/lab/swtc.htm
Havent tried that yet... I'm probably gona use some kind of simple 3 or 2 band EQ next time but these tone controlls look pretty cool.
van, the amount of controllable gain and the "9V question" are 2 different problems. the heaters on 12a_7 valves can be run at 6V wired in parallel or 12V wired in series, as they are shown in the doublemaster diagram. at 6V they draw twice the current, but the doublemaster still wants 18V on its plates. there are circuits in this thread (I would hope so, given its title) describing 9V plates and 6V heaters. also ways to get more than 9V from a 9V supply.
as for the gain, 2 x ax might work and pose no probs for you, or it might just scream all the time. once you have your sockets wired right, you can just plug and play, you could even try 12at7 (I think that's the right number). I've never used this series valves in this type circuit, only some low-gain vhf (6V heaters only) types I have. toplak might be better able to tell about the overall gain here.
Quote from: zambo on April 12, 2014, 06:29:00 PM
Quote from: dynotouch on April 12, 2014, 01:36:16 PM
It's purdy much built but not working yet(??). didn't have a 12au7 to test with so i tried a 12ax and got nothing at all and vdc from a battery dropped to about 5.3v when measured from the plates and the heaters were only getting something like 3v or visa-versa so i'm not doing something right (besides the obvious of trying the 12ax7). also i have the physical circuit spread out over a 8"x 6" board so i wonder of thats too big for such low current and voltage?? waiting on a 12au7 in the mail and need to find filtered and regulated 9vdc psu(has anyone here aver built a pedal apt supply... is there another thread dealing with that kind of build??) ....I'll go back over my work and report. thanks!
Btw: (i'll be simultaneously starting an component upgrade & mod project to my vintage ibanez cs9 st chorus pedal and searching for input and suggestions about that on another thread somewhere more subject orientated as such)
12ax7 doesnt always work in this design. Cant remember why. to much plate resistance or something. at7 same thing. Some do work, but its hit and miss. 12au7 works consistently. you probably built it right.
Quote from: Jdansti on April 08, 2014, 11:24:04 PM
Sounds good. Let us know how it turns out!
Been away working N stuff but now I'm back with a 12au7 in hand and the report is IT WORKS! ..well sorta :/ it powers up and the preamp is active and seems to be working from somewhere close to the tone control-on as it gets amplitude boost and frequency control but haven't yet figured why my guitar signal isn't making it thru and input gain control doesn't seem to do anything, but the output pot does seem to be working. using vintage A&B 100K type J pots for both (...no right??) probably something simple. I'll spend a little time with it today and see if i can get'er going. thanks!
there is a resistor frim grid to ground ( 1M ) if you have that in the wrong place it doesnt work. try that first. should be from pin 2 to ground. should be one from pin 7 to ground as well. I dont recall the stock schematic.
You might want to try it without the tone control. It sucks - literally!
Hi guys - I obviously missed some parts of this thread...
Still I am quite satisfied with my Valvecaster. I modded it with an TL072 in front of the tubes for some extra drive and run the tubes with apprx. 50-60 V supplied with a charge pump.
Now I want to add a cab Sim (maybe the condor from ROG) and a headphone out - and I have no idea how to do this... Did anyone try this?
I guess, I can just put the cabsim right behind the valvecaster - but do I need an additional headphone amp behind this circuit?
Can I go directly into the condor (powered with 12V), after my valvacaster, which puts out about +/-10V?!?
You can go right into the cab sim. just turn the volume on the VC down. It functions as a master volume in the position that it is in.you may have to turn it down quite a bit if your running 50v on the plates but no big deal. Headphones would be after the cab sim to get you the sound your looking for. Would love to build the condor cab sim.
Thanks for replying!
I tried - and failed... I think I made some mistakes while building the Condor. Have to try again...
Ok, you think I can just put the volume down - that means, I would lower my outpout from some 10 V to something, the cabsim can handle... Sounds logical to me ;)
I tried putting the headphones directly to the valcaster - first with volume all the way down. Than I pulled it slowly up. Also with full volume, I only get a very quiet signal.
Why is this not working, but is supposed to work with the cabsim?
its a impedance mismatch. you could try a resistor in series or even a 1 meg pot wired as a variable resistor. I dont know how much R you would need thus the pot. Ive tried it before and had it worlk like a transformerless amp of sorts, but it didnt work well or sound overwhelmingly good or loud for whatever thats worth. Try the cab sim and just put your out put volume around 1 or 2on the vc and it should be fine. you may need to run the cab sim into a headphone amp if it doesnt have a headphone out due to the impedance mismatches. it seems to be an issue.
You will need a headphone amp after the cab sim to drive the headphones. The condor cab sim will not drive headphones effectively.
Quote from: mth5044 on May 05, 2014, 04:32:19 PM
You will need a headphone amp after the cab sim to drive the headphones. The condor cab sim will not drive headphones effectively.
This.^^
A ruby amp works well for this
Ok. So its much more effort than I thought, but I will try. I will try and see, what I get for an output signal from the cab sim. Maybe a one stage headphone tube is sufficient.
Is there any good simple cab sim? Maybe even driven by tubes and not by Op amps?
Please, in advance, excuse my noobish ignorance.
This will be my first attempt at building something beyond a simple fuzz circuit using a transistor and clipping diodes on a breadboard. Using the Beavis Audio layout (http://www.beavisaudio.com/Projects/ValveCaster/MatsuminValveCasterWiring.gif), I cannot figure out how to add a DPDT bypass switch.
I have scanned each of the 150+ pages in this thread and, obviously, seen the physical examples of those who have done it, but no one seems to have posted how it is actually done.
Can I assume that the wiring of a bypass switch is fairly universal from box to box, or am I missing something?
Once again, excuse my ignorance, this is my first time out of the gate, and I'm anxious and excited to build this thing.
If someone could post a simple schematic or layout, or point me in the right direction I would be greatly appreciative.
Thanks, and thanks for such a killer site and forum!
DG
Welcome.
Yes a bypass switch is pretty universal and can be introduced to this circuit however, my experience is that such a switch is not always necessary with this circuit. It's an overdrive which appears to me to work better by overloading the input of your amp. The overloading increases the volume so you end up turning down the output volume to compensate. A switch will, in this case give you a big drop in volume when the valvecaster is bypassed. Lowering the guitar volume however is magic. Everything cleans up nicely
Perhaps others experience something different so please wait for them to chime in.
Anyhow, enjoy your build.
Oh and the circuit you linked to is simply built on the base of a valve socket. Just wire it up as in the picture.
Hi there.
If you mean to a foot switch, here you go...(not DPDT but works)
http://i47.photobucket.com/albums/f191/krinor/Valvecasternylayoutmkabler.jpg
Another link...
http://i25.tinypic.com/1zpp3r6.jpg
Hope it helps yaa.
Cheers,
Isak E.
bypassed side
0---0
from input-----------0 0----- to output
to C1---- 0 0-----from volume
circuit side
Hope this makes sense. 0 are the pins of dpdt. 3pdt is best to use as you should ground the volume ( silence the tube side ) when bypassed ( stops the ringing/oscillating that occurs when you eventually put two or three of these in a row to make a distortion pedal like most of us do..lol..) and hook up the led. welcome to the darkside lol :)
Thanks for your replies and help! Sincerely appreciated!
DG
Hi... First post.... Yay!!!
I have spent a considerable amount of time reading this whole thread and pasting all my favourite tips and bits into a reference document. I then built 2 amps inside some old tube radio enclosures. ( I was given then empty so I haven't destroyed any cool old radios).
I built the ValveCaster as a preamp into a TDA2003 chip amp in both radios. Radio 1 is an old Ekco using it's original 5x7 Rola speaker. I really like it a lot. Radio 2 is a bigger Rolls Radio that I have put a 12" Peavey speaker in. I built that one for a friend... with a clean boost version of the VC.
I had collected a small choice of tubes and have settled on a Philco 12AE7 in the Ekco and a Russian ECC99 in the Rolls.
I am really happy with both of them and would like to thank everybody who has contributed to this thread over the years. I would never have made it to this stage without you. I have learned a lot and am planning a twin VaveMaster + Tremolo + Delay pedal to follow up.
I'll post Photo's of the radios as soon as I take them
Yay!!!!..... Cheers!!!!
Firstly, welcome to the forum :)
Secondly, that sounds awesome! I'm currently working on a hybrid amplifier build (trying to get my feet wet before jumping into all-tube amp building ::) ) and my preamp section is based on the valvecaster. I'd love to see your pictures when you get around to it ;D
Thanks for your comments. Pictures will be forthcoming
OK, I took some pictures. My photography skills however are almost as lacking as my electronics skills.
I haven't posted pictures on a forum for a long time so I hope this works.
(http://<a%20href="http://s1319.photobucket.com/user/SGMB/media/IMG_0560_zpsb09bd0b2.jpg.html"%20target="_blank"><img%20src="http://i1319.photobucket.com/albums/t673/SGMB/IMG_0560_zpsb09bd0b2.jpg"%20border="0"%20alt="%20photo%20IMG_0560_zpsb09bd0b2.jpg"/></a>r)
(http://<a%20href="http://s1319.photobucket.com/user/SGMB/media/IMG_0561_zps12f156f3.jpg.html"%20target="_blank"><img%20src="http://i1319.photobucket.com/albums/t673/SGMB/IMG_0561_zps12f156f3.jpg"%20border="0"%20alt="%20photo%20IMG_0561_zps12f156f3.jpg"/></a>)
(http://<a%20href="http://s1319.photobucket.com/user/SGMB/media/IMG_0565_zps3ce6b12d.jpg.html"%20target="_blank"><img%20src="http://i1319.photobucket.com/albums/t673/SGMB/IMG_0565_zps3ce6b12d.jpg"%20border="0"%20alt="%20photo%20IMG_0565_zps3ce6b12d.jpg"/></a>)
(http://<a%20href="http://s1319.photobucket.com/user/SGMB/media/IMG_0563_zpsb31e45b1.jpg.html"%20target="_blank"><img%20src="http://i1319.photobucket.com/albums/t673/SGMB/IMG_0563_zpsb31e45b1.jpg"%20border="0"%20alt="%20photo%20IMG_0563_zpsb31e45b1.jpg"/></a>)
(http://<a%20href="http://s1319.photobucket.com/user/SGMB/media/IMG_0566_zpsdcc7eed5.jpg.html"%20target="_blank"><img%20src="http://i1319.photobucket.com/albums/t673/SGMB/IMG_0566_zpsdcc7eed5.jpg"%20border="0"%20alt="%20photo%20IMG_0566_zpsdcc7eed5.jpg"/></a>)
OK.... So I am a bit scared of showing these cos I know the workmanship here is not exactly fantastic. However it really does sound good and is a great little at home practice amp. The cardboard is a simple reflector to illuminate the radio dial in the same way that the original radio did, except this one is using leds. The voltage reguator in front of the tube is there to bring the led voltage down to 9v, everything else is running at 12v. I had a few of these 12v power supplies lying around. They are way overkill but very low ripple. It cleaned up even more with the extra cap across the terminals.
I like using the aluminium tape as a ground bus and shield. The TDA 2003 amp was a kit from evilbay. It looks like they have stopped selling the kit but you can still buy the assembled board for about $10... How?... I don't know.
The tube socket is mounted in the smallest enclosure I could find and the Valvecaster is assembled on the socket. This has no tone control and the volume control was replaced with a trimpot. I've tried a few different tubes before I settled on the Philco 12AE7.
I left the original radio labelling on the front but even though it says TONE - ON/OFF VOL - TUNING - RADIO/GRAM, It is actually INPUT - VOL - GAIN - ON/OFF
It's pretty obvious really. I don't think anyone would get too confused.
I know it's not that pretty inside with the cardboard reflector and everything but it wasn't really meant to be inspected. I am really happy with it in any case.
I haven't taken photo's of the one I made for my friend cos I haven't seen him in a while. Perhaps I will take some soon.
Oh well, let me know what a mess I've made and how stupid I have been... Cheers
(http://://s1319.photobucket.com/user/SGMB/embed/slideshow/"></iframe>)
Hmmm... my photo's aren't showing up
(http://[url=http://s1319.photobucket.com/user/SGMB/media/IMG_0560_zpsb09bd0b2.jpg.html%5D%5BIMG%5Dhttp://i1319.photobucket.com/albums/t673/SGMB/IMG_0560_zpsb09bd0b2.jpg)[/URL][/img]
Quote from: sgmb on June 27, 2014, 09:24:38 PM
(http://[url=http://s1319.photobucket.com/user/SGMB/media/IMG_0560_zpsb09bd0b2.jpg.html%5D%5BIMG%5Dhttp://i1319.photobucket.com/albums/t673/SGMB/IMG_0560_zpsb09bd0b2.jpg)[/URL][/img]
Looks like there's some extra info in your photobucket link. Try copying the "direct link" from photobucket.
(http://i1319.photobucket.com/albums/t673/SGMB/IMG_0560_zpsb09bd0b2.jpg)
(http://i1319.photobucket.com/albums/t673/SGMB/IMG_0561_zps12f156f3.jpg)
(http://i1319.photobucket.com/albums/t673/SGMB/IMG_0565_zps3ce6b12d.jpg)
(http://i1319.photobucket.com/albums/t673/SGMB/IMG_0563_zpsb31e45b1.jpg)
(http://i1319.photobucket.com/albums/t673/SGMB/IMG_0566_zpsdcc7eed5.jpg)
Ok. Thanks for that tip. I got there in the end. It is a nightmare trying to upload photos using an iphone. My advice... Don't
Cool retro look! :icon_cool:
Not to be negative, but I have some concern with the mains power wiring technique. Maybe it's "technically" ok, but it could possibly be hazard. I'll let the EEs comment on that. Otherwise, it's a really nice looking build!
I'd be worried if you weren't concerned. I don't plan on sticking my fingers in it though. I think it's as dangerous as any of my other amplifiers. I wouldn't stick my fingers in them either:)
Damn!..I deleted a whole lot of extraneous pictures from photobucket and I seem to have accidentally deleted some of the ones I posted. I don't know how I did that.
Do you use the iphone photobucket app? It seems to work well for me.
Ekco and Eko, just to confuse us. that is a beatiful looking cabinet, the stripes are v. nice. pitty we can't see the wiring mess.
So im another relatively novice tinkerer trying to make a valvecaster... Im running at 12v 1A walwort and using jjECC82 tube. The tube glows, and the signal is going through; the gain and volume pots seem to work, and the tone control is doing something, but the output volume is really low, essentially no boost at all. Ive looked at a few schems. and rechecked my wiring over and over, finding nothing. Any ideas out there as to what may be happening? Thanks
Dylan
Quote from: Jdansti on June 28, 2014, 05:12:35 AM
Do you use the iphone photobucket app? It seems to work well for me.
I didn't know about the iphone app. I too the convoluted approach. The deletion was just due to me being a dumb ass.
Quote from: duck_arse on June 28, 2014, 10:31:42 AM
Ekco and Eko, just to confuse us. that is a beatiful looking cabinet, the stripes are v. nice. pitty we can't see the wiring mess.
The wiring is actually fairly tidy...not brilliant but fairly tidy. Jdansti was referring to my setup where the power cord is strain relieved and attached to a tag strip which connects the power switch.
Quote from: dill pickle on June 28, 2014, 12:11:59 PM
So im another relatively novice tinkerer trying to make a valvecaster... Im running at 12v 1A walwort and using jjECC82 tube. The tube glows, and the signal is going through; the gain and volume pots seem to work, and the tone control is doing something, but the output volume is really low, essentially no boost at all. Ive looked at a few schems. and rechecked my wiring over and over, finding nothing. Any ideas out there as to what may be happening? Thanks
Dylan
This has come up a few times through the thread but I don't remember what the solution was. I'm sure it's there somewhere. One thing that has been mentioned is that the JJ tubes don't work particularly well in the valvecaster circuit. I don't know why and I haven't tried them, I'm just going by memory.
Quote from: dill pickle on June 28, 2014, 12:11:59 PM
So im another relatively novice tinkerer trying to make a valvecaster... Im running at 12v 1A walwort and using jjECC82 tube. The tube glows, and the signal is going through; the gain and volume pots seem to work, and the tone control is doing something, but the output volume is really low, essentially no boost at all. Ive looked at a few schems. and rechecked my wiring over and over, finding nothing. Any ideas out there as to what may be happening? Thanks
Dylan
Now that I think about it I always used GE tubes for my valvecasters and JJ for my twincasters. Not entirely sure why, but that's what I did. I didn't have any trouble with the JJ's in the twin, so I can't imagine it would be a problem in a valvecaster. Has the tube been tested to ensure it's a good tube?
Hey thanks for the response, im just getting back from a canoeing trip and back to the bench! I have two brand new jj 12au7s from tube depot, and i tried both, same results. I also have an old GE 12ax7 that i tried just to see what it would do, having read that they work, but dont sound good. It was the same result, signal getting through but no amplification at all. Ive searched the thread but didnt really find anything that helped. Im about to take everything apart and start over, hoping to catch my mistake that way. Is there a schematic that people like more? Seems like there is some discrepancy between ones ive seen.
After the awesome read of this entire thread since January up till now I've been tinkering with some of the schematics here and decided that I really needed a valve drive before my tube top.
These were the schematics I started out with:
(http://www.cosmicandroid.com/ValveCaster/Twin-Triode-Twin-basis.jpg)
I had some 12A*7 tubes to work with and after careful, thirsty consideration and testing on the breadboard:
(http://www.cosmicandroid.com/ValveCaster/Twin-Triode-Twin-Proto1.jpg)
I came to this schematic:
(http://www.cosmicandroid.com/ValveCaster/Twin-Triode-Twin-Schematic.jpg)
Further design needed to be made for inside and out:
(http://www.cosmicandroid.com/ValveCaster/Twin-Triode-Twin-pcb.jpg)
(http://www.cosmicandroid.com/ValveCaster/Twin-Triode-Twin.jpg)
And at this stage I've just etched, and drilled the pcb:
(http://www.cosmicandroid.com/ValveCaster/TwinTriodeTwin-pcb1.jpg)
The reason for the two different switches is that I have some DPDT swithes lying around, so I aim to use them here and there with millennium bypass switching.
As I could find a cheap 24V adapter at conrad's there was no need to keep the voltage at 9v.
I tried different tubes with different voltages but the 18/12 volt version sounds the best with 12AX7 and 12AY7 tubes.
I've tried all kinds of tonestacks but the simplicity of the original design seemed to end up winning every time.
So I ended up with a double tube drive where the 12AY7 simply drives and next to that a 12AX7 drives with a simple tone pot.
That's all for now, I'll keep you posted on further results!
Oh, and for the tubes I've tested from left to right: Sovtek 12AX7, Electro Harmonics 12AY7, JJ ECC83 S and two RCA 12AU7's
(http://www.cosmicandroid.com/ValveCaster/Twin-Triode-Twin-Tubes.jpg)
The Sovtek and Electro Harmonics I use in the 24V Twin Valvecaster.
The JJ tube doesn't give out enough drive power, so with the information of other builders it seems JJ's are not really suited for Valvecasting...
The RCA tubes work well on 12volt with this schematic:
(http://www.cosmicandroid.com/ValveCaster/Twin-Triode-Twin-Schematic2.jpg)
The RCA tubes are cleartops so they look better in a build like this where they will be exposed.
If the first build works out I'll try to do this 12V version as well.
That's a hell of a post Demon. Looking forward to the finished build.
Agreed. One hell of a post. My hat is off to you sir
yeah, i'm sorry, that's just my ocd kicking in once in a while. But rest assured, the end result will not look as uptight as the designs :D
Allright, build it, works, but...
came across a lazy mistake in the pcb image, forgot to rotate D1 and C12 when I moved the 24vdc line to the right of the Gnd, so the verified pcb is this:
(http://www.cosmicandroid.com/ValveCaster/TwinTriodeTwin-pcb4.jpg)
And another strange thing is that the the led on the right, after the millenium bypass, is not as bright (barely visible) as the one on the left, tried to lower the value of R14, and even bypassing R14, but it won't get any brighter...
Ideas anyone?
(http://www.cosmicandroid.com/ValveCaster/TTT-10.jpg)
The etch of the box didn't come out real sharp, still have to figure out a better way to etch these boxes, but it looks nice and vintage this way...
(http://www.cosmicandroid.com/ValveCaster/TTT-06.jpg)
Very nice build and material!
Any chance of some soundsamples?
you might try changing to a mosfet for the millenium, it works much more the way you'd expect. watch the pinout.
Yep, thanx, had been sniffing around in the millenium articles and found this page http://www.geofex.com/article_folders/bypass/bypass.htm (http://www.geofex.com/article_folders/bypass/bypass.htm)
Where it sais: "Using a high-threshold JFET or one with a low Idss will mean that the LED won't turn completely off, and may not be very bright when it's "on". Using a low-threshold JFET and one with an Idss rating of 5ma or more will give a much better change in on-to-off brightness in the LED. You can also use a diode or two in series with the LED to sharpen things up a bit."
So I changed the J201 for a 2N5485 and that's a little better, the 2N5475 does a little less...
I also have some BS170's but that means changing the circuit a little bit...
yes, j201 is not your friend here. your above linked-to and problems is exactly why I went to the mosfet version. and you'd really want those 2n's for some audio work, no?
I put the 2N5485 in some feet so I can reclaim it when I get around making a little mosfet millenium daughterboard, but first I wanted to play with the soundoptions for a while ;D
I've made a little video testrun of the pedal, on bass, as I'm a bass player... Don't think I'll make a guitar version, I'm just too terrible on six strings :icon_redface:
Hi everyone,
I am an Electrical Engineering Major working on my senior project. What I want to do is to put the matsumi 9v tube circuit into the Build Your Own Clone 5 knob compressor. I am trying to put it all in one enclosure but have to PCB's one for the COMP and one for the tube. Would I just be able to put the output of the comp into the input of the ValveCaster, also would I be able to remove the the volume section on the ValvCaster and tie that in to the volume on the compressor?
You can run the valvecaster right into the compressor as long as you no longer want the ability to turn either stage on or off, although without the volume control, you might clip the input of the compressor. You might be better off using an internal trimpot and set the amount of volume going into the compressor.
MY FIRST TUBE BOX :P
(http://ww4.sinaimg.cn/bmiddle/6d092e56gw1edyakrxhcyj20cw0b4ab6.jpg)
that's a nice looking thing xi. can we see inside as well? (and welcome to the forum.)
I've got another thread going but maybe I'll get more responses here. Since I have the other thread, I'll provide the jist of what's going on.
Original Thread: http://www.diystompboxes.com/smfforum/index.php?topic=108569.0
What I Have: Valvecaster as a preamp, 10-watt TDA2030 power amp, 5" Celeston neodymium driver (pulled from a Trace Elliot cabinet)
The Problem(s):
1) I have to turn the volume and gain all the way up in order to get loud.
2) My biggest problem is the lack of crunchy goodness I'm hearing in all the YouTube videos (http://www.youtube.com/watch?v=3cMqYlhSQ8c)
Quote from: teej on September 29, 2014, 01:17:36 PM
I've got another thread going but maybe I'll get more responses here. Since I have the other thread, I'll provide the jist of what's going on.
Original Thread: http://www.diystompboxes.com/smfforum/index.php?topic=108569.0
What I Have: Valvecaster functioning as a preamp fed into a 10-watt TDA2030 power amp.
The Problem(s):
1) I have to turn the volume and gain all the way up in order to get loud.
2) My biggest problem is the lack of crunchy goodness I'm hearing in all the YouTube videos.
I actually experimented with doing the same thing a while ago and could never get it working :-[
Quote from: vigilante397 on September 29, 2014, 01:23:02 PM
Quote from: teej on September 29, 2014, 01:17:36 PM
I've got another thread going but maybe I'll get more responses here. Since I have the other thread, I'll provide the jist of what's going on.
Original Thread: http://www.diystompboxes.com/smfforum/index.php?topic=108569.0
What I Have: Valvecaster functioning as a preamp fed into a 10-watt TDA2030 power amp.
The Problem(s):
1) I have to turn the volume and gain all the way up in order to get loud.
2) My biggest problem is the lack of crunchy goodness I'm hearing in all the YouTube videos.
I actually experimented with doing the same thing a while ago and could never get it working :-[
I'm glad to hear it's not just me. I can't for the life of me figure out why this doesn't work. In principle, it seems straight-forward. Signal leaves the Valvecaster, amplified by the TDA2030 and out the driver.
The Valvecaster / TDA2030 combo is a little amp I'm building for my wife who is learning guitar and likes metal, which is why I need crunchy distorted goodness. Once I get my amp running again (jacks and switches overhaul), I'll test just the Valvecaster through it to hopefully pinpoint the problem.
First Vid: (http://img.photobucket.com/albums/v343/teejofca/JID/NoiseBox/th_MVI_0456_zpsdcdfbc92.mp4) (http://img.photobucket.com/albums/v343/teejofca/JID/NoiseBox/MVI_0456_zpsdcdfbc92.mp4)
Second Vid: (http://img.photobucket.com/albums/v343/teejofca/JID/NoiseBox/th_MVI_0457_zps12a64d11.mp4) (http://img.photobucket.com/albums/v343/teejofca/JID/NoiseBox/MVI_0457_zps12a64d11.mp4)
(http://img.photobucket.com/albums/v343/teejofca/JID/NoiseBox/0919140715-01_zpsca0d47a3.jpg)
I've tried running a Valvecaster into a simple 3 watt amp (Velleman P8066). This is also unsuccessful. In my case, the 8066 is designed to take a wide variety of input signals and strengths without much overload so there is obviously some input compression going on. This makes overdriving the amp near impossible and while a signal actually passes through to the speaker, the sound quality is very poor.
I wonder if something similar is going on with your TDA2030?
Quote from: stallik on September 29, 2014, 02:13:25 PM
I've tried running a Valvecaster into a simple 3 watt amp (Velleman P8066). This is also unsuccessful. In my case, the 8066 is designed to take a wide variety of input signals and strengths without much overload so there is obviously some input compression going on. This makes overdriving the amp near impossible and while a signal actually passes through to the speaker, the sound quality is very poor.
I wonder if something similar is going on with your TDA2030?
That could very well be. I tested my valvecaster separately first and it worked beautifully (found myself a vintage Mullard 12AU7 ;D ) but for some reason when I threw the TDA2030 into it it just kind of died.
Bet the Mullard sounded good. Interestingly, old Mullard and Brimar AX7's sound great in the Valvecaster while modern equivalents don't. I'm using a JAN AU7 which is great and these old AX7's sound about the same. Go figure...
It appears to me the input impedance of the IC amplifier is dragging the gain down of the valvecaster.
The output of a valvecaster normally is connected to the input of a guitar amplifier which is high impedance - 470k or 1M.
Try putting a fet buffer similar to that in a Ruby, or noisy cricket between the valvecaster and the TDA2030.
Quote from: tonyharker on September 29, 2014, 03:22:25 PM
It appears to me the input impedance of the IC amplifier is dragging the gain down of the valvecaster.
The output of a valvecaster normally is connected to the input of a guitar amplifier which is high impedance - 470k or 1M.
Try putting a fet buffer similar to that in a Ruby, or noisy cricket between the valvecaster and the TDA2030.
I'll give the buffer a try. Now to find a buffer circuit that will work...
this is my third edition
(http://ww2.sinaimg.cn/bmiddle/6d092e56jw1ekybivcik7j20di0i0769.jpg)
Hello,
I made the Valvecaster and I did not listen the "drive" or the "crunch" sound in this effect. Is there any modification that I could make to addition a little bit of distortion in the sound ?
I found some videos about the Persuader that it used a MOSFET to this finality. The schematic for the Persuader is in the MOD's website, but it is not much useful.
Quote from: teej on September 29, 2014, 01:17:36 PM
I've got another thread going but maybe I'll get more responses here. Since I have the other thread, I'll provide the jist of what's going on.
Original Thread: http://www.diystompboxes.com/smfforum/index.php?topic=108569.0
What I Have: Valvecaster as a preamp, 10-watt TDA2030 power amp, 5" Celeston neodymium driver (pulled from a Trace Elliot cabinet)
The Problem(s):
1) I have to turn the volume and gain all the way up in order to get loud.
2) My biggest problem is the lack of crunchy goodness I'm hearing in all the YouTube videos (http://www.youtube.com/watch?v=3cMqYlhSQ8c)
This is very interesting to me because it is almost the same setup that I built in my old radio on page 171. I used a TDA 2003 and my speaker is a 5X7 eliptical rola but really it all sounds the same.
I had to put a trimpot between the valvecaster and the TDA2003 to bring the level way down. It seems I had the opposite problem.
I have started building a new pedal.
Although I've built 3 valvecasters in the past, this is will be the first one I've put in a pedal... the others have been preamps in diy amplifiers.
I am combining a Beavis Audio Trotsky drive with a valvecaster in one pedal. I think the brightness of the trotsky will balance the darkness of the Valvecaster quite well. I'll put the trotsky first and do an interstage gain on the valvy.
I am hoping someone could give me some suggestions as to how I might arrange the power supply. Ideally, I'll have 9v to the trotsky... 12v to the heaters and 24v or more to the valvy circuit.
I'm yet to plan the best way to do this from a single wallwart.
Does anyone know if the Trotsky will run on 12v?... not that it matters too much... a 12v to 9v regulator wouldn't be hard.
Cheers guys.
Yes. Just run the Trotsky on 12 volts. No problem.
Oh cool, thanks.... In that case I may as well just run the whole thing at 12v. I haven't tried higher voltages yet but I've been pretty happy with 12v so far
Cheers
Thought I would post my mods for giggles. These are for the original Dano/Matsumin Valve Caster.
-Get rid of the tone stack. You'll find you can get the dry and wet signals to match pretty much by changing caps.
-Brighten it up by controlling the bass. The second cap (between stages) can be a .033 or .022. This will cut out a lot of fizzle and make it far less dark.
-Change the gain pot to a 100kC. Optional: 10K resistor between the pot and ground. This smooths out the gain a lot and makes the potentiometer usable.
And finally, after these tweaks, you can use a 12AX7 with it! Really. I tried Sovteks, Chinese, GT's and Mesa Boogies. I had surprisingly good overdrive results with everything but the GT's. Those were a joke. Run it at 12 Volts though. It tends to sag a little at 9 or 10 volts with a 12AX7.
I didn't experience the sag when using 12AU7's at 9.6V and it sounded very good. So either way you should be able to make something work.
Cheers!
Quote from: ayayay! on December 01, 2014, 09:51:53 PM
Thought I would post my mods for giggles. These are for the original Dano/Matsumin Valve Caster.
-Get rid of the tone stack. You'll find you can get the dry and wet signals to match pretty much by changing caps.
-Brighten it up by controlling the bass. The second cap (between stages) can be a .033 or .022. This will cut out a lot of fizzle and make it far less dark.
-Change the gain pot to a 100kC. Optional: 10K resistor between the pot and ground. This smooths out the gain a lot and makes the potentiometer usable.
And finally, after these tweaks, you can use a 12AX7 with it! Really. I tried Sovteks, Chinese, GT's and Mesa Boogies. I had surprisingly good overdrive results with everything but the GT's. Those were a joke. Run it at 12 Volts though. It tends to sag a little at 9 or 10 volts with a 12AX7.
I didn't experience the sag when using 12AU7's at 9.6V and it sounded very good. So either way you should be able to make something work.
Cheers!
Got rid of the 10K after the gain pot. Added a 150pF on the output to tame the fizzle and brightness. This thing sounds great and matches my bypassed tone closely enough to be very usable. I settled on the .033 between stages. You can run it at 9V just fine if your power supply has enough current. I'm using a 1A. I think you need at least 400mA for it to truly work well.
Hello everyone. I'm new here and also new at electronics. :) So what I got, I have 24V adapter from drill, and two tubes 6N2P-EV. I'm thinking of building two tube valvecaster, tubes will be heated through LM317 at 6,3V and anode will be fed with 24V. Do I need to change resistors or any capacitors in the valvecaster schematic in order to run it at 24V? Any suggestions how to improve this without going to high voltages? Thank you and sorry for my bad English ;D
Hello guys :) been reading this thread for a while now, trying to construct a dual valvey (going to try the new schematic from Trippy).
I'm searching for help in prototyping a line tube preamp for my POD XT for in between the POD and interface to fatten and smooth up the tone.
I just can't understand how to match impedances and gain levels for those... I don't even need any amplification gain in there, but something more like cathode follower, I can go on even decreasing gain, my pod puts a lot of volume out.
The big idea is to build a small circut which can be then fitted inside the pod itself :D
Please help me guys.
I will later post my idea how the schematic should look like (need to draw it first)
Cheers,
Max.
Quote from: id3m on December 12, 2014, 03:46:21 PM
Hello guys :) been reading this thread for a while now, trying to construct a dual valvey (going to try the new schematic from Trippy).
I'm searching for help in prototyping a line tube preamp for my POD XT for in between the POD and interface to fatten and smooth up the tone.
I just can't understand how to match impedances and gain levels for those... I don't even need any amplification gain in there, but something more like cathode follower, I can go on even decreasing gain, my pod puts a lot of volume out.
The big idea is to build a small circut which can be then fitted inside the pod itself :D
Please help me guys.
I will later post my idea how the schematic should look like (need to draw it first)
Cheers,
Max.
Here's a schematic I've thought of: https://www.dropbox.com/s/1bcp5prpzanljyg/New%20Doc_1.jpg?dl=0 (https://www.dropbox.com/s/1bcp5prpzanljyg/New%20Doc_1.jpg?dl=0)
The first half is a clean (?) valvey with fixed bias, worked in my test.
The second half is a cathode follower. I just copied its schematic from P1 extreme.
Tell me please - will this work? Any ideas on this scheme?
How could I know if the circuit is in series or parallel.
I connect the out of SHO to the in of the Valvecaster and it worked very well, but after 20min the pedal stopped suddenly.
I noticed that the tone control (of the valvecaster) was not working. I changed the electrolytic capacitor (of the valvecaster board - 1uF) and the pedal came back to live again. Well, only for more 20 min and then stopped again.
Why this capacitor is breaking ? and it is working only for a few minutes ?
Check the cap voltage, has to be written on it. Sometimes electrolytic aluminum caps are only 10-16v, which is not enough. Try tantalum electrolytic.
Hey all,
I'm half way through building my first valvy, there are just have a few things I feel like I should double check before I can continue with the build, and would definitely appreciate a little assistance.
So in this diagram...
http://img155.imageshack.us/img155/3599/valvecasterv05qs5.jpg
...C3 is labeled as being 1uF, but I've noticed there are other diagrams in this thread which have C3 as being 1nF.
Are both diagrams correct? I've bought a 1uF for this build, so I'm hoping I have the right thing.
And speaking of C3, from my understanding of the diagram, the negative is connected to the tone pot, while the positive goes to track 6 of the board. Am I right on this?
One last thing. The pots in the diagram are shown from the bottom, right? So if the lugs on the pots were numbered form left to right the order would be 3, 2, 1. Is this correct or am I reading this all wrong.
I imagine it's clear to most reading this, that I'm pretty new to this electronics thing, I've learned heaps, but clearly have a long way to go, and would really appreciate any assistance anyone can offer.
Cheers.
Andy
the circuit diagram will reveal all. that's why we like to see them.
(http://www.beavisaudio.com/projects/ValveCaster/MatsuminValveCaster.gif)
your 1uF appears on the original, so it should be ok. if you follow its connections, one end goes to ground via the 100k vol pot, the other end goes to +9V via the 100k resistor. on end will be more positive than the other, it should be easy to work out which.
for the tone control wiring, C4 is in series with the tone pot, so it doesn't matter if it is at the signal end or the earth end of the pot. when confronted by a layout diagram with pots not marked cw/c (or w)/ccw, look for the volume pot. ground will always be on (or via a small value resistor, to it) the counterclockwise lug. you can then work backwards as to the 1-2-3-edness of the lug numbering convention used.
or look the circuit, work it out from the source, and apply it to your parts yourself, cuts out the middleman. same goes for values on layouts.
have you been to geofex to read "the secret life of pots"? there is much in there to answer some of your future questions.
Hey thanks Duck Arse, you've helped me out a few times now.
The secret life of pots looks like a great resource, I'll definitely be reading it when I have some time, later today.
Do you have suggestions for any other reading I should be doing, as someone who's new to this pedal building caper?
read everything at both geofex and amz, they'll tell you plenty you'll need and want. they show how to design the stuff that beavis puts together. and over at ampage you can see just how many pedals mark hammer can do mods on. you can use the search button ^, there have been a couple of threads on reading resources.
Teej,
Do you have any info in that Power supply?
Hello,
Is there any valvecaster layout with 4 knobs or an additional switch SPDT ?
Thank you.
Quote from: alambike on February 17, 2015, 12:08:06 AM
Hello,
Is there any valvecaster layout with 4 knobs or an additional switch SPDT ?
Thank you.
Probably. What do you want said 4th knob or SPDT to accomplish?
Quote from: vigilante397 on February 17, 2015, 12:18:17 AM
Quote from: alambike on February 17, 2015, 12:08:06 AM
Hello,
Is there any valvecaster layout with 4 knobs or an additional switch SPDT ?
Thank you.
Probably. What do you want said 4th knob or SPDT to accomplish?
Hello,
I would like to use one more alternative for the sound. For example, a new knob to give distortion or a switch that can do the same thing. I am looking for a valvecaster mod distortion with 4knobs or a switch ...
Thank you !
Quote from: alambike on February 17, 2015, 09:21:21 AM
I would like to use one more alternative for the sound. For example, a new knob to give distortion or a switch that can do the same thing. I am looking for a valvecaster mod distortion with 4knobs or a switch ...
I have seen some people put clipping diodes on a DPDT switch and use them for an additional switching option, I have also seen people put an LPB-1 type clean boost before the valve stage to get a little more gain.
Quote from: vigilante397 on February 17, 2015, 09:41:34 AM
Quote from: alambike on February 17, 2015, 09:21:21 AM
I would like to use one more alternative for the sound. For example, a new knob to give distortion or a switch that can do the same thing. I am looking for a valvecaster mod distortion with 4knobs or a switch ...
I have seen some people put clipping diodes on a DPDT switch and use them for an additional switching option, I have also seen people put an LPB-1 type clean boost before the valve stage to get a little more gain.
I tried to put the SHO with the valvecaster but It did not work very well. The valvecaster stops working after some time using it.
What circuit could give more distortion? The clipping doides or another booster?
Quote from: alambike on February 17, 2015, 11:54:47 AM
What circuit could give more distortion? The clipping doides or another booster?
You would get more distortion with clipping diodes, but you are going to lose a bit of volume when the diodes are engaged because that's part of how clipping diodes work.
As for a boost I really like the EHX LBP-1 because it has low parts count, all the parts are fairly common, and it's so simple of a circuit that it's frankly hard to mess up. With the SHO did you try it before the Valvecaster or after? Before will affect the tone, after will affect the volume. Another alternative I've tried (as I'm sure have many others) is running two Valvecasters together.
Quote from: vigilante397 on February 17, 2015, 10:52:12 PM
Quote from: alambike on February 17, 2015, 11:54:47 AM
What circuit could give more distortion? The clipping doides or another booster?
You would get more distortion with clipping diodes, but you are going to lose a bit of volume when the diodes are engaged because that's part of how clipping diodes work.
As for a boost I really like the EHX LBP-1 because it has low parts count, all the parts are fairly common, and it's so simple of a circuit that it's frankly hard to mess up. With the SHO did you try it before the Valvecaster or after? Before will affect the tone, after will affect the volume. Another alternative I've tried (as I'm sure have many others) is running two Valvecasters together.
Helo,
Using the SHO I tried after and before the valvecaster and in Both cases it failed. In this case the tone control stops working and, consequently, the pedal.
I will try to put the LPB-1 now.. Another thing, where is the right place to add the clipping diodes in the valvecaster? .
Quote from: alambike on February 17, 2015, 11:35:35 PM
I will try to put the LPB-1 now.. Another thing, where is the right place to add the clipping diodes in the valvecaster? .
Right before the volume pot. See the schematic (sorry for the crude drawing, I was feeling lazy so I edited Beavis' schematic in paint).
(http://i.imgur.com/G6xiWAv.gif)
I would recommend trying 1N914's or 1N4148, or whatever you have around. If you're feeling really adventurous there are plenty of experiments you could try with germanium, or even some asymmetrical clipping options.
^ or...
Take the clipping circuit and move it to its own little box. You can do different configurations such as symetrical/asymmetrical with a switch. Then place the box after the Valvecaster or any other high gain box to add diode clipping.
Quote from: Jdansti on February 20, 2015, 03:57:16 AM
^ or...
Take the clipping circuit and move it to its own little box. You can do different configurations such as symetrical/asymmetrical with a switch. Then place the box after the Valvecaster or any other high gain box to add diode clipping.
That is a good idea, didn't even think of that. Very good option for flexibility.
The clipping circuit will work better before the volume control
^Right. If you do the separate box, you'd want to run the Valvecaster on full volume and you can put a volume control in the new box after the diodes.
Quote from: Jdansti on February 20, 2015, 05:22:37 PM
^Right. If you do the separate box, you'd want to run the Valvecaster on full volume and you can put a volume control in the new box after the diodes.
Helo,
When you talk "new box", you mean: an aluminium box (hammond) or only construct a new circuit and connect it before the volume pot and active ir using a switch spdt on-on to turn on/off When the distortion is necessery.
Another thing, how could I make a LPB with clipping diodes ?
Quote from: alambike on February 20, 2015, 07:49:40 PM
Quote from: Jdansti on February 20, 2015, 05:22:37 PM
^Right. If you do the separate box, you'd want to run the Valvecaster on full volume and you can put a volume control in the new box after the diodes.
Helo,
When you talk "new box", you mean: an aluminium box (hammond) or only construct a new circuit and connect it before the volume pot and active ir using a switch spdt on-on to turn on/off When the distortion is necessery.
Either way. I was just giving you another option. You can put the diodes in the Valvecaster as Vigilante described as long as you put them before the volume pot as Ripdivot described, or you could make a separate clipping box with the diodes and a volume control in it. Place this box after the Valvecaster (or any other high gain effect), crank up the Valvecaster so that the diodes will clip, and use the volume control in the clipping box to control the amplitude of the signal going to the next pedal or your amp.
Same thing with the LPB. Put the clipping diodes before the volume pot or make a clipping box and place it after the LPB as described above with the Valvecaster.
BTW-I've never used an LPB, so I'm not sure if it has enough gain to make the diodes clip. Maybe someone else can address this.
Quote from: Jdansti on February 20, 2015, 08:24:35 PM
Same thing with the LPB. Put the clipping diodes before the volume pot or make a clipping box and place it after the LPB as described above with the Valvecaster.
BTW-I've never used an LPB, so I'm not sure if it has enough gain to make the diodes clip. Maybe someone else can address this.
It's going to depend on the diodes. If I remember right I got some nice clipping out of 1N914's, but it not so much with 1N34A's.
Hi!
I have read around 100 pages of this topic....it's amazing, I really want to build a Valve Caster with 2 stage 12AU7 at 9 volts with tone controls.
Which page should I search for the schematic of a final version of it?
I'm not sure there is a final schem, it's more of a starting point. you might as well start here:
http://www.beavisaudio.com/projects/ValveCaster/
then work out what you have and what you want.
As I recall, someone spliced two valvecasters together in the first 10-15 pages, or so, of this thread. Also try searching for Twincaster, there are some vero layouts in the gallery.
My 2d worth on clipping. I've used 1N4148s hanging off a double pole on, off, on switch. Off is no clipping, the 2 ons are symmetric and assymetric. When clipping is switched in, there is a volume loss so I used the other pole on the switch to introduce a 500k resister to the direct signal. All volumes are equal now but I find I don't particularly like the clip :icon_neutral:
Quote from: duck_arse on March 05, 2015, 09:13:40 AM
I'm not sure there is a final schem, it's more of a starting point. you might as well start here:
http://www.beavisaudio.com/projects/ValveCaster/
then work out what you have and what you want.
Thanks for the answer, 2 quick questions:
1. what's the main difference in sound when you use the alternative scenario with 12Vdc+lm317(6.3V)?
2. Any links/sellers for getting 12AU17/6111 at reasonable price?(shipping to europe)
1) if you have 12V DC in, use that for 12xx7 series. the heaters can be run series (12V) or parallel (6V). the lm317 will get stinky hot dropping 12V to 6V, and you won't need it at all for 12V operation. as for the sound difference, I can't say, I've never run heaters at wrong volts.
2) can't help you here, I'm in australia.
when you say "2 stage", do you mean a single valve with 2 triodes, or 2 valves for 4 triodes?
Quote from: duck_arse on March 06, 2015, 08:45:20 AM
when you say "2 stage", do you mean a single valve with 2 triodes, or 2 valves for 4 triodes?
thanks! I found something like this:
http://www.instructables.com/id/The-Valve-Caster-20-Tube-Boost-and-Overdrive/?ALLSTEPS
that's what I meant "2 stage", 2 valves/tubes. I have built a few diy projects but this will be my first including tubes. I am looking forward to it!
I read lots of these pages, I am definitely wiser before I started this project,
I built valvecaster 2.0 with two tubes in the row JJ and electroharmonix golden pin.
Electroharmonix is just amazing, JJ is so-so.
Now I have a question,
Is there an alternation of the schematic so I can use valvecaster for an acoustic quitar(piezo)? Could it be as simple as trying other tubes, 12AT7/12AX7? or other makes Mullard, rca, etc?
Is there an valvecaster version for acoustic instruments? I tried valvecaster with electroharmonix golden pin and JJ, and my acoustic guitar sounded distorted :(
Should I change some resistance values?
Should I try other tubes? 12AX7?12AT7? other makes?Mullard, rca, etc?
or can you suggest any other simple schematic for acoustic preamp/pedal?
Hi guys,
Thanks for all these posts. Would it be possible to use this as a "filter" for my acoustic instruments? I really like the warmth and compression of a tube, so a version/alteration which would not distort/overdrive the signal would be great.
Any ideas?
Many thanks in advance!
Marc
Welcome to the forum :) The best way to use this pedal in an overdrive-free situation would be to stick with the 12AU7, which are lower gain than the 12AX7, 12AT7, etc. You would probably also want to experiment with resistor values to substitute for the gain pot to give you a "stuck clean."
Thanks Vigilant, that would mean higher value resistors for the gain, right? In what range would you advice to experiment?
I have Philips 12AU7's that have a really "hifi" characteristics, also.
The gain pot for the original circuit is 50k, so I would guess something in 30k - 40k range. An additional option would be to replace the gain pot with a trimpot and adjust it until you have the maximum gain you will want in the circuit then just leave it there.
Thanks again!
I guess I'll make two versions for electric and for acoustic (with the trimpot).
Cheers
Just finished mine with 6111 tube.working like a dream.I have one problem only.i need more volume when the pedal engaged.power is 12vdc.what can i change?or a 6112 with mu70 will do the job?feed it with higer volts?adjust anode resistors?just need more volume.what do you suggest?
Hi all! I'm going to put one of these together as my first DIY stompbox project. Super excited!
I've been reading through the thread, learning things, but I have a few questions I can't find answers to since this thread is huge.
I want to run it at 18V to get more headroom and get a cleaner boost. I know I need to add a resistor to drop the heater input to 12.6 V. Are any other modifications required?
I'm not really sure what most of the resistors and caps actually do. I'm happy to figure that out by experimenting, but are there any that would be a really bad idea to change?
Thanks heaps. Glad to be here.
Quote from: rugeb on March 07, 2012, 08:16:10 AM
Schematic with last mods:
(http://www.fuzzface.es/mods/ValveOverdrive+Mods.jpg)
Hi guys,
Can you verify if this vero is correct??
(http://i1175.photobucket.com/albums/r628/vgtpedals/valvecaster%20with%20diode%20clipping_zpsgui1jxjk.jpg)
Thank you very much!!
Quote from: lluis3.0 on April 07, 2015, 01:51:47 AM
Quote from: rugeb on March 07, 2012, 08:16:10 AM
Schematic with last mods:
(http://www.fuzzface.es/mods/ValveOverdrive+Mods.jpg)
Hi guys,
Can you verify if this vero is correct??
(http://i1175.photobucket.com/albums/r628/vgtpedals/valvecaster%20with%20diode%20clipping_zpsgui1jxjk.jpg)
Thank you very much!!
I forgot to mention that the SW is an SPDT on off on switch.
Hi all!
valvecaster is my first diy stompbox project. I made a prototype on the breadboard and was happy with the sound and decided to build a real thing using a stripboard and altoids can box. I decided to make my own stripboard design. Yesterday I finished soldering and powered it on and was not happy with the noise which is coming out when i turn off the gain pot. Also there is noise coming out of it when I touch any potentiometer. The distortion is not working, only tone pot affects the sound. On the breadboard all was fine. Here is my schematic:
(http://i60.tinypic.com/v58mj6.png)
I am not into electronics and cant understand what caused that. Any help much appreciated, Thank you.
Okay, looking at building one of these, with a few mods. I'm thinking of putting a mosfet booster before it to get more gain out of it, but I'm curious what I should do with the valvecaster's gain pot in that case - obviously I don't want two gain pots. If it helps any, I'm looking for more of an overdrive than a boost.
Quotewhat I should do with the valvecaster's gain pot in that case - obviously I don't want two gain pots.
well, th!nk, someone's going to come in and tell you to call it "drive" instead, so it may as well be me.
"call it 'master' instead."
Heh, very good. I guess I'll find a value I like with it in there and then replace it with a resistor. Should probably have thought of that earlier to be honest.
Funkyjunky - the components look like they are laid out ok but your gain pot isn't connected properly. You need to switch the connections of 2 and 3. That way the gain will increase as the shaft is turned clockwise. This won't fix the noise problem though. Check your connections and look for solder bridges. Running a knife along the grooves will cut bridges if there are any. Also check your component values. If that doesn't help refer to this page for debugging:
http://www.diystompboxes.com/smfforum/index.php?topic=29816.0 (http://www.diystompboxes.com/smfforum/index.php?topic=29816.0)
I finished breadboarding my build, and I'm waiting for parts to box it. I tried swapping out caps and resistors to try things, and turned out preferring the original values. The only mods are losing the tone knob (superfluous, and ditching it brightened the sound), and running it at 18 V. With the extra headroom, the boost sounds delicious, and the growl at high gain is still fantastic. I tried a new-built JJ, and a 1960's-built Sylvania. The Sylvania is going in the final build.
Hello everyone - first post here
I'd like to build a version of the Valvecaster as a complete low watt practice amp. I'm thinking about putting the output of the VC into a TDA2003. I've scanned the thread ( well, parts of it :icon_wink: ) for clues and it seems the low input impedance of the TDA2003 is a problem. Could anyone suggest a buffer circuit to put between the two ?
Would the first one here do ? http://www.beavisaudio.com/techpages/Buffers/ (http://www.beavisaudio.com/techpages/Buffers/) - I have built this already as a guitar\soundcard interface and it works fine.
Thanks !
Sid! welcome to the madhouse.
the output impedance of the valvecaster should be adequate for the tda, which I think has op-amp inputs? in this case, the input impedance is determined largely by the resistor used with (chosen for) the tda.
have a look for the tube cricket at beavis.
Thanks ! - what is confusing me is that two guys mentioned that they tried to hook the VC up to a TDA2003 without success, while pages earlier another guy showed some pictures of his two builds into old radio chassis which were fine. No actual details of the circuits involved though.
I'm not sure what to think really ??? I see what you mean about the Tube Cricket schematic...could it be as simple as the value chosen for the volume pot ?
Quote from: vigilante397 on April 03, 2015, 09:59:51 AM
Welcome to the forum :) The best way to use this pedal in an overdrive-free situation would be to stick with the 12AU7, which are lower gain than the 12AX7, 12AT7, etc. You would probably also want to experiment with resistor values to substitute for the gain pot to give you a "stuck clean."
Not sure if the person who asked the question this addresses still cares, but running at 18 V substantially increases clean headroom. You'll need a 36-ohm, 2-W resistor in the heater loop.
I thought I'd join up to say thanks to everyone. The Valvecaster was my first pedal after I searched out a simple project to start on. (I'll be starting my 6th pedal soon)
My version was a standard point to point build but with a 22nf input cap. I've since added a FAL treble boost before the input cap that I found on this forum. I had to use a J201 in the boost because I didn't have a 2n2222 in my small but growing parts stash but it works fine after a bit of leg bending. The tone knob now has some work to do. I run it at 12v for best results.
http://bayleysweb.wix.com/steves-airbrush-odyssey#!__guitar-effects/photostackergallery0=0
Hey guys.. I am considering building a standard valvecaster with a different input cap for better results with humbuckers and need your opinions.. Would this be a decent dirty boost to use in front of a distorted marshall? I am looking to add a little more tube gain to my Class 5, for more of a 2203 sound (think slash I guess, but you know the sound). Any opinions on that? I can't for the life of me find a vid that demos the pedal as anything but a standalone overdrive. Drivin' me nuts! :icon_mrgreen:
Quote from: ghostsauce on May 09, 2015, 03:39:21 PM
Hey guys.. I am considering building a standard valvecaster with a different input cap for better results with humbuckers and need your opinions.. Would this be a decent dirty boost to use in front of a distorted marshall? I am looking to add a little more tube gain to my Class 5, for more of a 2203 sound (think slash I guess, but you know the sound). Any opinions on that? I can't for the life of me find a vid that demos the pedal as anything but a standalone overdrive. Drivin' me nuts! :icon_mrgreen:
I'm sure this pedal would be great for that. Frankly I've had trouble finding anything it isn't great for. I'm not sure you would need to adjust the input cap as it sounds great with every guitar I've thrown in front of it.
Cool. Perusing the intarwebz, the general consensus seems to be that it the standard value is good for singlecoils, but:
QuoteChange the input cap (C1) to 22nF and its a whole new game. Lots of ACDC-esque tone, lovely response and works well with humbuckers
So maybe I'll socket it then and try both, not a switch since I only have HB guitars right now anyways. Anybody attempt the above?
Yeah, with the Fender Atomic Humbucker on my Strat. I preferred the 47, but those are my ears. Try both and let your ears decide.
Will do! And lastly, what the heck do you call those roll bars used on valvecasters? And where do you find em?!
You can use a C clamp or metal cupboard door handles.
Quote from: ghostsauce on May 10, 2015, 04:08:13 PM
Will do! And lastly, what the heck do you call those roll bars used on valvecasters? And where do you find em?!
I personally prefer the look of these for externally mounted tubes, but that's just me.
http://www.ebay.com/itm/130678756876?_trksid=p2060353.m2749.l2649&ssPageName=STRK%3AMEBIDX%3AIT
Sweet, I was wondering where those came from. I went with mounting a tube socket from the inside and using standoffs to get it to the right depth. Now I just gotta snag a step drill bit that will do a big enough hole to fit the tube and I'm set. Hoping to snag one from my local hardware store.. but that might not be doable.
Actually, I do have another question.. think this power supply will be ok with it? - http://smallbear-electronics.mybigcommerce.com/wall-transformer-12-volt-ac-ac-1-amp/
I can't tell if it's regulated or not, but it's 12v / 1000mA at least.
There's also this one: http://www.ebay.com/itm/AC-Power-Adapter-12V-DC-Supply-2a-amp-regulated-Wall-Wart-Charger-5-5-mm-2-1-mm-/181579405953?pt=LH_DefaultDomain_0&hash=item2a46f9da81
Any thoughts? What did you guys use?
I would definitely trust the one from Smallbear, partially because I trust everything from Smallbear (they're amazing) and partially because it's from Electro-Harmonix. I'm not positive it's regulated, but I would imagine it's at least filter. The one from eBay is most likely neither, and it's also center positive (standard for pedals is center negative) so if you do go for that you should either take that into account while building or (more preferable) modify the power supply to be center negative.
Quote from: ghostsauce on May 11, 2015, 03:30:07 PM
Actually, I do have another question.. think this power supply will be ok with it? - http://smallbear-electronics.mybigcommerce.com/wall-transformer-12-volt-ac-ac-1-amp/
I can't tell if it's regulated or not, but it's 12v / 1000mA at least.
There's also this one: http://www.ebay.com/itm/AC-Power-Adapter-12V-DC-Supply-2a-amp-regulated-Wall-Wart-Charger-5-5-mm-2-1-mm-/181579405953?pt=LH_DefaultDomain_0&hash=item2a46f9da81
Any thoughts? What did you guys use?
the first one puts out
AC, the second one
DC.
Quote from: snap on May 12, 2015, 02:34:08 AM
the first one puts out AC, the second one DC.
EXCELLENT point, can't believe I didn't catch that :P Very big difference there. Try a Visual Sound One Spot, regulated 9v DC and filtered.
Alright, I actually have a spare 1spot. I think they make a 12v version too so I'll probably order one.. Keep reading that it sounds much better on 12v. Thanks for the help folks!
Where can i get the original Schematic?
Quote from: DiogoSoares on May 22, 2015, 04:57:20 PM
Where can i get the original Schematic?
It used to be on page 1, but it disappeared. You can find it here:
http://www.marshallforum.com/tone-zone/54615-valvecasters-other-diy-tube-pedals.html#post837867
Holy tone enabler, Batman! This thing is unreal!
(http://www.ghostsauce.net/random/pics/vc1.JPG)
(http://www.ghostsauce.net/random/pics/vc2.jpg)
I'm using my 9v 1spot right now, and have a 12vDC 500mA regulated supply in the mail.. but even at 9v it is fantastic. Had to use a 22nF input cap to sound best with my humbuckers, but otherwise it is the original version. I am using it to goose my class 5 right now into sonic bliss, but I've found that I can set the amp clean and use the VC on it's own for gain with excellent results that sounds just as good although a little different than my amp's gain, and it's in pedal format so I can run delays after it. This thing is a frickin' godsend. It really shines as a boost though. Since the amp is NMV, I set it for ACDC and use the valvecaster to boost it to scorpions. :D
The tube in the pic is a Tungsol 12ax7, but I am actually using it with a Jan/Phillips 12au7. It's just amazing. Lots of low end too, and really nice and crisp up top when the volume is above unity, not dark at all.
Thanks everybody for your contributions to this thread. :D
That's a very handsome build!
Nice job Ghostsauce. Like the way you've dropped the tube
I put this one together to try adding some diode clipping. (symmetric/none/asymmetric) on a 3pole switch. First time I've tried that on a valvecaster & it certainly adds a lot of extra grind. Wrapped in carbon vinyl that I had laying around.
(http://www.stallibrass.com/images/kas/vc4.jpg)
Guts are a bit messy but it works
(http://www.stallibrass.com/images/kas/vc4guts.jpg)
Dude, that looks really great.
So many great builds of this pedal. I finally got a pic up so I could share my version.
(http://i.imgur.com/aHB4zSP.jpg)
I like it! The "Taxi Drive" :D
Now you have to use a white rectangular LED that says "Occupied"- maybe mount it to the forward tube protector bar.
taxi? I thought it was a bee or wasp, with even the stinger sitting atop the valve.
I'm going to say that my taxi drive idea makes more sense than the bee/wasp thing, but only because I want to be right.
I was thinking when I painted it I'd do a warning sign style graphic and call it 'Caution - Overdrive'. Maybe I should do a checker stripe and go for the New York cab look instead? Although New York is over 10,000 miles (17,000km) from where I live.
and how far away is the nearest bee/wasp, pray tell?
Quote from: duck_arse on June 09, 2015, 11:04:17 AM
and how far away is the nearest bee/wasp, pray tell?
Adelaide.
EMG81 > Valvecaster set loud and kinda dirty > Marshall Class 5. (heavy EQ'ing on the solos though)
http://www.ghostsauce.net/random/Akriloth%202015.m4a
Aww yeah.
Sounds great! :D
Hello all,
I tried building a valvecaster off the bevis pcb-less schematic. The valve is warming up but I'm getting no sound when engaged. Any ideas? Thanks!
(http://images.tapatalk-cdn.com/15/06/21/2f39e1c4fe3adf4c7bef0461d9736f9c.jpg)
(http://images.tapatalk-cdn.com/15/06/21/c3b2d96c6c3033ddffa26d17f6813b28.jpg)
A ground was connected from dc jack when tested. I also was able to run the signal in at the output from the tube socket and it worked from there so I built a second tube socket assembly and no luck with that either.
This is the first "socket assembly" I tried
(http://images.tapatalk-cdn.com/15/06/21/904a002528de34792c0ab6effd8a46c5.jpg)
I think I've tested all continuity and components at this point.
Any constructive criticism would be helpful, this is my first build so I really have no clue what I have done wrong.
I build a valvecaster on perfboard and just finished it up last week. When I fired it up, no sound. But the tube was warm. I tried it 2-3 times, and looked the pedal over. Turns out I didn't do anything wrong in the building part, I just didn't let the tube warm up long enough. So later on I tried it again, this time I plugged it in and left it for 5-10 minutes, came back started playing and it worked! I kinda felt a little stupid, I thought for sure I messed something up while building it :P In my defence this was my first tube build, I'm not an expert on tubes yet.
I'm using my valvecaster with a bass guitar, it sounds awesome!! But only one thing, C1. I need to change it to a bigger value to allow for more bass to come through. It's not a big loss on the low end and I could live with it. Thought about maybe putting two caps on a switch to have the option between the two.
fuzzyhead - are you running your (12V) heaters at 9V?
Quote from: duck_arse on June 23, 2015, 11:16:16 AM
fuzzyhead - are you running your (12V) heaters at 9V?
I used 9V to test it to see if it worked, but I will be using 12V.
@fuzzyhead
Hi, what is the value for C1 to go with your bass?
Thanx.
Quote from: Frittenkirk on June 24, 2015, 01:15:43 PM
@fuzzyhead
Hi, what is the value for C1 to go with your bass?
Thanx.
The value for C1 is 47nf. I'm thinking I'll put in a bigger value for C1 though. Not that there's anything wrong, I like it, but there is a bit of low end that's lost with a 47nf. Nothing big, just slight. If I end up liking a bigger cap for C1, I might put the two caps on a switch. Because I do like the 47nf even though there is a bit of loss on the low end, but again, it's not a big loss, just a slight loss.
Hi fuzyyhead
Thanx a lot for the fast reply.
Here's my two-knob build.
(http://img.photobucket.com/albums/v481/suncrush/e9c22437-3091-47d8-b937-99fdd8c941ce_zps95dxmfdg.jpg) (http://smg.photobucket.com/user/suncrush/media/e9c22437-3091-47d8-b937-99fdd8c941ce_zps95dxmfdg.jpg.html)
Holy cow! This thing sounds amazing. I'm running it at 18 V, which gives me more clean headspace, but it still growls and grunts like crazy. It beefs up my sound like a champ on low gain. I haven't scoped it, but it sounds like I'm getting a little low-mid hump, and it sounds great.
The tube is a NOS Sylvania 12AU7 from somewhere between 1960 and 1966 (was warmer than my new-built JJ). I soldered the components to stripboard and jumpered to the socket, and no, you can't see my solder job. It's not as nice as the one on the last page. ;)
I'll decal it just as soon as I figure out what to call it.....
I'm thrilled by my first diy pedal, and a thank you to all of you who provided advice along the way. This is a super board.
Quote from: suncrush on July 13, 2015, 07:51:23 PM
I'll decal it just as soon as I figure out what to call it.....
Call it "RED". No decals required. ;)
Hi all, my name is Brendan and I'm from Australia. This is my first post and it's great to finally be part of this forum. I have started to acquire the parts needed to build my first Valvecaster and I'm very excited about it. I'm not new to DIY, but this will be my first valve build. I've built loads of overdrive, fuzz and boost pedals with great success. I'm planning on building a 2 pot version without the tone control with stock component values. But will use a socket for C1 so I can experiment with different caps and find the right frequency for my bass guitar.
All I need to order is my valve and valve socket, then I'm ready to go. After much research and reading this whole thread, I've settled on a Russian made Tung-Sol 12AU7/6189 valve. Does anyone here have any experience with this particular valve in this circuit?
There has been a lot of awesome builds in this thread. I'm looking forward to seeing and hearing more.
Mmmm! Must of posted in a dead thread :icon_lol:
not dead, fuzzf, just resting. you know how slow those bass players are .......
also, welcome to the forum, from a c0ckroach.
Thanks for the welcome. Seeing your handle and the way you spell arse would I be right in guessing you're another Aussie? Are there many others here?
Hi FuzzFanatic & welcome.
Not used bass with the Valvecaster but it's my experience that C1 is necessary to prevent things becoming too bass heavy. That makes me think that with the right cap in place, it should be successful with the lower frequencies. It's a good idea to socket it while you debug. If you can't make up your mind, you can always insert a switch to change between 2 or more.
Nor have I used a Tung Sol but I've tried many other 12ua7's and they all give very good results. Interestingly, I've also used old 12ax7's from Brimar and Mullard and they also work really well though more modern equivalents don't. I'm running all of mine at 12 volts DC.
Good luck with your build and don't forget to post the results.
Quote from: FuzzFanatic71 on July 27, 2015, 12:00:34 PM
Thanks for the welcome. Seeing your handle and the way you spell arse would I be right in guessing you're another Aussie? Are there many others here?
arse, c0ckroach, yes, north of the border, nsw. not many, but we have a few cobbers in each state, it seems. give a coo-ee anytime.
Quote from: duck_arse on July 28, 2015, 10:41:40 AM
Quote from: FuzzFanatic71 on July 27, 2015, 12:00:34 PM
Thanks for the welcome. Seeing your handle and the way you spell arse would I be right in guessing you're another Aussie? Are there many others here?
give a coo-ee anytime.
No worries mate, will do. Never really heard the expression %^&*roach for Aussies.
And thanks for the advice and warm welcome stallik.
:icon_lol: check that out, auto censorship.
not c0ckroach for aussie, for new south welshman. cane toads (banana benders), c0ckroachs, mexicans and brother lovers, north to south down the east coast states.
and yes, the censor smites at all odd times. b@#*&%d!
You just dated yourself mate. Those terms were just a bit before my time. My dad uses them. The only ones I heard growing up was banana bender QLD, crow eater SA and sandgroper WA.
We had better get this thread back on topic.
Just a quick noob question. If I wire 2 caps together in parallel, do I get the combined of those 2 values? Eg. 47uf + 10uf = 57uf
Quote from: FuzzFanatic71 on July 29, 2015, 03:50:06 AM
Just a quick noob question. If I wire 2 caps together in parallel, do I get the combined of those 2 values? Eg. 47uf + 10uf = 57uf
Yep.
(https://cdn.sparkfun.com/assets/0/5/4/0/c/51ba3809ce395f445b000000.png)
And in series it's like resistors in parallel, i.e. the reciprocal of the sum of the reciprocals:
(https://cdn.sparkfun.com/assets/e/f/5/8/c/51951385ce395f3f1f000001.png)
I just started my first Valvecaster build. Hopefully everything will work out ok.
I just finished my first Valvecaster build for my bass board and it was a major success. Warmed up my sterile solidstate bass amp nicely. It definitely won't be my last valve build. The next will be for my guitar board. For that one I'm thinking of putting in a clipping diode circuit.
Has anyone done any experimenting with low hfe ge transistors as clippers in this design or any other dirt pedal? I think I read somewhere that you just join the base and collector to form the cathode, and the emitter becomes the anode. Correct me if I'm wrong.
(http://s1292.photobucket.com/component/Download-File?file=%2Falbums%2Fb574%2Fbrendan_chaplin%2Fimage.jpg2_zps2kp62i3h.jpg)
Mmmm, was hoping just the pic would show up. Bummer!
Quote from: FuzzFanatic71 on August 23, 2015, 02:02:38 PM
Mmmm, was hoping just the pic would show up. Bummer!
Wrap your URL in [
IMG] [/IMG]tags, and it will.
That'll teach me to try to give a smart answer using Tapatalk...
Oh, OK. It came out as I intended (just swapped to a browser). Just Tapstalk unable to display what I wanted. :icon_rolleyes:
That's ok, Marc. Now go back to sleep. ;D
Quote from: bluebunny on August 23, 2015, 04:26:47 PM
Quote from: FuzzFanatic71 on August 23, 2015, 02:02:38 PM
Mmmm, was hoping just the pic would show up. Bummer!
Wrap your URL in [IMG] [/IMG]tags, and it will.
Done, thanks!
Quote from: FuzzFanatic71 on August 24, 2015, 01:47:29 AM
Quote from: bluebunny on August 23, 2015, 04:26:47 PM
Quote from: FuzzFanatic71 on August 23, 2015, 02:02:38 PM
Mmmm, was hoping just the pic would show up. Bummer!
Wrap your URL in [IMG] [/IMG]tags, and it will.
Done, thanks!
Worth the wait! Looks great, Brendan. :icon_cool:
Quote from: Jdansti on August 23, 2015, 06:45:47 PM
That's ok, Marc. Now go back to sleep. ;D
Thank you Dr. Danna. Been to sleep. Had my first coffee. Now slowly beginning to make sense... ;D
I keep bumping this old thread that no one seems interested in anymore. Sorry if I'm being a pain in the arse. I'm just excited about it I guess.
I ended up doing a clipping mod to my valvy. I didn't really get any dramatic and noticeable tone changes with the input capacitors on the switch, so I decided to turn it into a clipping switch instead.
OA1160 Tungsram Germanium Diode pair is on one side of the switch, and 1s1588 Toshiba Silicon Diode pair is on the other. Middle position is no clipping. For anyone who wants their Valvecaster to be more of an overdrive or distortion, I highly recommend this mod. I'm really loving it. You will have to increase the volume when switching on the diodes but I think you guys probably already knew that. Anyway, just thought I'd share.
(http://s1292.photobucket.com/component/Download-File?file=%2Falbums%2Fb574%2Fbrendan_chaplin%2Fimage.jpg2_zps2kp62i3h.jpg)
Here's mine. (http://www.diystompboxes.com/smfforum/index.php?topic=64752.msg1031488#msg1031488)
Quote from: Papa_lazerous on December 12, 2007, 08:03:21 PM
Quote from: kurtlives on December 12, 2007, 05:56:33 PM
Could you post a vero layout?
Does the tube light up btw?
The tube will have to light up or it wouldn't conduct....
You could do as the picture above and put most components on the tube socket, or even a nice little tag board layout. Its really such a simple build it might be a good learning excersize to try and make your own layout and then post it here and ask someone to check it over. Should only take a short time ;)
Heya - I'm just gonna make one of these but cant see your pic. I'm into the idea of building it off the back of the tube holder. Any chance you could repost the pic? Thanks
Here is mine. I'm very interested about the diode clipping. Is there any way to increase the volume while switching the diode stage to prevent the volume waste?
(https://lh3.googleusercontent.com/lFZVdW008av4RSYEE7_3mjePefz5sVrV3233F06wQXQprOG8U2y7riuwkgsBuvh2YEdaCqVitXjs5GOXy9qeSOhb0eYEoSze8_l0XCBv4XgsZxd-5809lI_G6hG3g0gZ_dvyWQA4CUT4rtiav2iW0gYrOupiRH4hyfA8ZShm6q5evwfC_i9n2M3n88FWfobPhpzlenE73xoFEM16FxwbuuXLQS-9SyvjsSirYs8MSnhCN7V2u8TlcHQ6UbYhwxA4x18IGgl4oMkBcqRS8FFTaeJYDH-o4847lUpDc3jW-lCBUU5XZrTNYuVEvd9tYn_VwnkdaqIfO9RxKmuAUBAhcHyGJeJrA6ScXFH7bX4ynGts-jfCA5zwDx_ObshrA3rI7OyZnoI807z7egHzk7Yw4cEkg2222rJpbLkK07oMkM3RopNBLsljbOXL6ayEjpAu6oAMJThFhEB_6rgY_CpV0O1hY54jCmwcBP0tyCCqZ2OovQPt3Ipwc4Yf_LIMia4fHxEXivqbJ7GP-SeH3f4UH56Pnfv_MhO9F_aVXw=w1287-h965-no)
(https://lh3.googleusercontent.com/9hdnvYg5MMwROY3wRqhGkXFv_0kKv1Uw8y6wOVzdF4pKYv-px3vZK5zWv6kw9mXFwjIKNCGtpzRdlQxJbznnUfbXE3_JSyn2JWXMRcSQWNEaJaapcAgIsRy635D4Ohs9Cr-gDS7S56o7hPlz9a7u4evhD_pJU03lAvTYbyO7rrf6qqKiWVaCJl_veCBQk17-vn4wWk6_0RUo0AL5jJZNRY9a9xXSU1TvlMcIc8A1UiW7LXIjJZhgutkTXbA8SSYNraQk81QQcAaH2uwpXc7jHFrXG0nb9U_bcgQXwl6jhEnrj3ahwAy_uU7bbt1-_28obgbJ4RrBvwJRhdwsAfM2H3KoKsL49Xm5z_ra0BUtpIOExH0jIJjeCQIZgbS_PFZ6vMYelMzmrv-R_pyYRk7NHejHm9iUEJ8NvgGGQofCknOZRZKLz70YsFLFMasuyLx2kiqP6dUaLlWIQTsNQ3WS9IfjGC4ZANodTPTxL--GJ9o6kIbvWSxOvpTuAk_Pi6UJ0I9v9FJNtNLjkPNLX55mMQl6Gb4IbS65TGkReg=w1718-h965-no)
Yes, I used a SPDT switch with the diodes on one pole and a resistor on the other pole
(http://www.stallibrass.com/images/kas/diodeswitch.png)
Choose the resistor value to even out the volume. Easy to wire on the switch itself
Thank you very much!!!
So the left OUT goes to ground, IN comes from after C3 and the resistor goes to Vol pot.
Quote from: lluis3.0 on November 06, 2015, 04:16:39 AM
Here is mine. I'm very interested about the diode clipping. Is there any way to increase the volume while switching the diode stage to prevent the volume waste?
(https://lh3.googleusercontent.com/lFZVdW008av4RSYEE7_3mjePefz5sVrV3233F06wQXQprOG8U2y7riuwkgsBuvh2YEdaCqVitXjs5GOXy9qeSOhb0eYEoSze8_l0XCBv4XgsZxd-5809lI_G6hG3g0gZ_dvyWQA4CUT4rtiav2iW0gYrOupiRH4hyfA8ZShm6q5evwfC_i9n2M3n88FWfobPhpzlenE73xoFEM16FxwbuuXLQS-9SyvjsSirYs8MSnhCN7V2u8TlcHQ6UbYhwxA4x18IGgl4oMkBcqRS8FFTaeJYDH-o4847lUpDc3jW-lCBUU5XZrTNYuVEvd9tYn_VwnkdaqIfO9RxKmuAUBAhcHyGJeJrA6ScXFH7bX4ynGts-jfCA5zwDx_ObshrA3rI7OyZnoI807z7egHzk7Yw4cEkg2222rJpbLkK07oMkM3RopNBLsljbOXL6ayEjpAu6oAMJThFhEB_6rgY_CpV0O1hY54jCmwcBP0tyCCqZ2OovQPt3Ipwc4Yf_LIMia4fHxEXivqbJ7GP-SeH3f4UH56Pnfv_MhO9F_aVXw=w1287-h965-no)
(https://lh3.googleusercontent.com/9hdnvYg5MMwROY3wRqhGkXFv_0kKv1Uw8y6wOVzdF4pKYv-px3vZK5zWv6kw9mXFwjIKNCGtpzRdlQxJbznnUfbXE3_JSyn2JWXMRcSQWNEaJaapcAgIsRy635D4Ohs9Cr-gDS7S56o7hPlz9a7u4evhD_pJU03lAvTYbyO7rrf6qqKiWVaCJl_veCBQk17-vn4wWk6_0RUo0AL5jJZNRY9a9xXSU1TvlMcIc8A1UiW7LXIjJZhgutkTXbA8SSYNraQk81QQcAaH2uwpXc7jHFrXG0nb9U_bcgQXwl6jhEnrj3ahwAy_uU7bbt1-_28obgbJ4RrBvwJRhdwsAfM2H3KoKsL49Xm5z_ra0BUtpIOExH0jIJjeCQIZgbS_PFZ6vMYelMzmrv-R_pyYRk7NHejHm9iUEJ8NvgGGQofCknOZRZKLz70YsFLFMasuyLx2kiqP6dUaLlWIQTsNQ3WS9IfjGC4ZANodTPTxL--GJ9o6kIbvWSxOvpTuAk_Pi6UJ0I9v9FJNtNLjkPNLX55mMQl6Gb4IbS65TGkReg=w1718-h965-no)
I like the look of this build, but the tube seems huge in comparison to the box. Or is it just the angle that the picture was captured from?
I've just thrown a valvecaster on my breadboard and it sounds fantastic in "standard" trim using a 1958 Sylvania tube. Lots of crunchy overdrive. Will be boxing it soon.
It must be the angle, It's a 12AU7 in a 1590BB box.
Thank you
I think i got it
With a 2PDT on-on R5 should increase the volume in case you turn on the switch up or down. In down position the clipping area is off.
Please, can someone verify?????
(http://i1175.photobucket.com/albums/r628/vgtpedals/valvecaster%20with%20diode%20clipping_zpszmvcwohy.png)
Hi all. This has been such a good read and all these valve pedals look great.
I finished mine last week. I built the Twincaster- Dual Valve caster and i've spent a few days trying to get it going to no avail. I built it as per the schematic and layout by Renegadrian. The only real difference is i put a blue LED in both tube sockets.
My drama is that with power on with no tubes it's ok and the LED's come on when i hit the footswitch. I then put one tube in and all ok but then when i insert the second tube,all the power goes and dies. I pull either of the tubes out and reconnect power and it's ok until i insert the tube again..
I've wired up another socket with a tube and wires and while one tube is inserted and power on,i insert the wires of spare socket one by one and have found that the pins 4 and 5 (heaters) are the ones that are causing the power to go.
I'm out of ideas other than to pull it apart and start again but thought i'd ask if one of you could help.
Any help would be much appreciated.
Cheers
Reddog - welcome to the forum?
Please have a look at this and provide us with your info:
http://www.diystompboxes.com/wiki/index.php?title=Debugging (http://www.diystompboxes.com/wiki/index.php?title=Debugging)
also welcome, and what power supply are you using? please provide the nameplate ratings if it's a wart.
Quote from: peterg on November 15, 2015, 08:27:43 AM
Reddog - welcome to the forum?
Please have a look at this and provide us with your info:
http://www.diystompboxes.com/wiki/index.php?title=Debugging (http://www.diystompboxes.com/wiki/index.php?title=Debugging)
Cheers peterg and duck, heres some voltages
Tube A empty B inserted
1 10.6v 6.89
4 1.4mv 2.6mv
5 10.8 10.8
6 10.7 5.2
Tube A inserted B empty
1 7.7 10.2
4 3.1mv 1.6mv
5 10.8 10.39
6 5.31 10.28
No Tubes in
A B
1 11.9 11.9
4 0 0
5 12.1 12.1
6 12 12
I've had a read of the debugging pages and on other sites. Thought i'd see if i can get a hand before i pull it out and start again.
I'm using 12 volt power supply but had no luck with the 7812 regulator. Wired 2 up and didn't work.. But i built a single tube valvecaster on a breadboard with the power supply i have and it was hum free so i thought i wouldn't bother with the regulator on this one. If i need it i'll make a separate unit. My ww is 18v 1000mA and i use the 12v outlet on my board.
can you post the circuit you're building to, save me reading all those pages?
Sorry duck,i'm not good with computers,i don't know how to post the circuit.
I don't expect you or anyone to go through this whole post to find the circuit either mate. I just thought any of the people who have built it and are familiar may have a few ideas off the top of their head. Cheers
Just a thought. How many milliamps of current does the 12v on your board pump out? I use a 500ma 12v for my Valvecaster in the pic at the top of the page. Your Twincaster might need at least 800ma to 1 amp to power both valves.
Thanks Fuzz, I thought the 18v 1A power supply would be ample. No? Maybe not? I was thinking it seems the heaters are the culprits when both connected but using only pins 4 and 5 it uses 12.6v/150mA. So it needs 300mA,i should have plenty of juice left shouldn't i?
Quote from: reddog22 on November 15, 2015, 06:31:48 PM
Thanks Fuzz, I thought the 18v 1A power supply would be ample. No? Maybe not? I was thinking it seems the heaters are the culprits when both connected but using only pins 4 and 5 it uses 12.6v/150mA. So it needs 300mA,i should have plenty of juice left shouldn't i?
I don't really know. I'm pretty much a newb when it comes to all this. I just make comments hoping that I'm on the right track. And then if I'm wrong which is usually the case, I just rely upon someone more learned piping in and correcting me. I don't ever feel dumb being wrong. I would feel dumber if I didn't ask.
No worries,cheers Fuzz
how have you wired the heaters? there is a number of ways I can think of because of the centre-split.
are you working from a circuit in this thread, or did you draw-up your own?
Quote from: duck_arse on November 16, 2015, 09:02:59 AM
how have you wired the heaters? there is a number of ways I can think of because of the centre-split.
are you working from a circuit in this thread, or did you draw-up your own?
Cheers,in my original post i had i have built this to the schematic and layout by Renegadrian and have followed it to the tee(as far as i can tell anyway) Pin 4 grounded and 5 to 12v.
alrighty, what are your pin 9 connections, they should be empty. you need to disconnect power and probe for resistances. first measure across the valve itself, see what the heater resistance is/are.
from the 12V line to ground w/ no valves, you should have, well, I dunno, a high reading (relatively, it will get lower). measure from pin 5 of socket 1 to pin 5 of socket 2 should show 0R, or your meter's idea of. do that same measure for pin 4/1 and pin 4/2, and the answer should be the same.
now stick in a valve, and measure resistance across the other pin 4 and 5. what value? pull the valve, swap into the other socket, you can see where I'm going with this ..... what value? now stick in both valves and measure across either/both 4's - 5's. should now be around 1/2 the single valve reading.
if not, why not?
Cheers duck,i appreciate yr help. I'll go through all of that later today and get back to you. Thanks
Quote from: duck_arse on November 17, 2015, 08:45:26 AM
alrighty, what are your pin 9 connections, they should be empty. you need to disconnect power and probe for resistances. first measure across the valve itself, see what the heater resistance is/are.
from the 12V line to ground w/ no valves, you should have, well, I dunno, a high reading (relatively, it will get lower). measure from pin 5 of socket 1 to pin 5 of socket 2 should show 0R, or your meter's idea of. do that same measure for pin 4/1 and pin 4/2, and the answer should be the same.
now stick in a valve, and measure resistance across the other pin 4 and 5. what value? pull the valve, swap into the other socket, you can see where I'm going with this ..... what value? now stick in both valves and measure across either/both 4's - 5's. should now be around 1/2 the single valve reading.
if not, why not?
I've just gone and done all the measurements.
Tube 1 in Tube 2 out
4. 0.1 4. 0.1
5. 0.1 5. 0.1
T1 out T2 in
4. 0.1 4. 0.1
5. 0.1 5. 0.1
T1 in T2 in
4. 0.1 ohm 4. 0.1 ohm
5. 0.1 ohm 5. 0.1 ohm
12v+ to - 20M ohm
So 0.1 for all of the heater resisitances.
mmm. well. to me, 0.1 looks like a short somewhere across the heater lines. when I measured the 3x 12a*7's I have here, they showed 14R pin4 - 5.
it seems you may need to unwire your heaters, and do them again.
how are you on posting photos?
Sorry to stick my oar in but at there's a little voice in my ear asking if the valve base is wired from the top or bottom as it were. I appreciate that this was bread boarded first but still....
Quote from: duck_arse on November 18, 2015, 08:30:04 AM
mmm. well. to me, 0.1 looks like a short somewhere across the heater lines. when I measured the 3x 12a*7's I have here, they showed 14R pin4 - 5.
it seems you may need to unwire your heaters, and do them again.
how are you on posting photos?
Ah,i get you now Duck. :icon_redface: Measuring the resistence across pins 4 & 5 on the same tube is 17.8 ohm's for both tubes.
ahh, no, maybe you're still missing my gist (ohh-er!)
we really, really need a circuit diagram for what you have built to show about now, so we can see what to expect across the heater connections on the empty sockets. I'm thinking you'll have a rectifier/cap looking into the heater, so it will read *some number* of ohms. your sockets show 0.1R across the mt heaters, so that looks to me like a short.
with both valves fitted, the 2 heaters should (*) be in parallel, and we would ekspekt about 8 or so ohms. at least we know your heaters are not open/short.
and anyone else carrying an oar, please! dip it in! bring life jackets and circuit dias, too.
Duck is right. Without a circuit diagram, we're all running blind. There is a circuit for a twincaster on these pages but it would be wrong to presume that you've used it. Please let us know which one you are using. Also, can you take pictures, upload them and send us a link? If you can't, PM me and I'll try to do it for you.
Now, one final thing. You state that all appears to work until you insert the second tube. How do you know that the second tube itself is not faulty? Have you tried both tubes in position one with nothing in position 2?
Here is my 1u monstrosity:
(http://i.imgur.com/BfSPrpj.jpg).
(http://i.imgur.com/uQb2Yg2.jpg)
It has had many versions, changes, mods, tests and failures.
The 12AU7 tube in the window is a later version of the Valvecaster.
which feeds into the 12AT7 tube, a banana boost.
(I removed a tube stage)
The control layout is:
6 Input cap selector for the Valvecaster
Gain for the Valvecaster
banana boost volume (main output volume)
Diode Distortion level pot.
6 Diode selector.
Valvecaster volume.
0-32 voltage adjuster (10 turn pot)
It is switched in/out with a relay controlled by a Rockman MIDI Octopus.
There is bright white 3 LED strip (on the bank of caps) to light up the tube.
I dig the overall character.
I use it to put a small amount of spice on the Carvin V3M's clean channel.
It was fun tinkering with it....but, wow...I would hate to count the hours.
Thanks to all who contributed...I learned a LOT!
~D
Thanks duck_arse and stallik for helping me out here. I have no idea on uploading photos and links and am over this pedal atm... I'm gunna have a break from it for a while. I'll put up a new post and let ya's know how it goes. Thanks again.
So, I came across this: http://stompage.juansolo.co.uk/btbuild.html
It's essentially a valvecaster with a proper gain control instead of the bias control we use for gain in the original. I already built one and would like to implement this gain control, but I'm struggling to figure it out if you guys don't mind proof reading for me here.. I *think* I just need to add a 47n + gain pot combo between pins 1 and 7, in addition to the 47n that's already there. Am I missing anything? Just wondering if I need to change anything else to make this work right. Toying with the idea of just building the boobtube instead and continue running it at 12v.
Here's the one I built:
(https://damacleod.files.wordpress.com/2011/03/matsuminvalvecasterlayout.gif)
Mandatory tone sample:
Sounds good right?! He's probably running it at 40v though like the link suggests, where I am running 12v. But hey, gotta experiment.
Well, I got around to trying it out and sure enough it does sound better than the previous bias adjustment knob. I removed the bias pot all together and pin3 now connects straight to ground. It's still not perfect, though.
In the vid he's got the level and gain on the pedal cranked, and it seems to be goosing his amp a little where before I thought all this glorious gain was coming from the pedal. When I do that I get pretty close to the sound he's got, but I think it needs more tone shaping. He's got a 470k and 100pF paralleled between C1 and pin 2, and I am guessing that this is shaping the EQ a little. EDIT: after some research.. seems like this is a high pass filter.. EDIT2: Actually no, neither part is in series with the signal. What do these do?
I also noticed he's got a 150n and 1.5k in parallel off pins 3 and also 8, so I'm going to attempt that and see what it's about. I'm thinking it biases the stages better?
>:(! I'm getting an annoying hum in my Valvemaster! The signal is ok until the valve's first stage but it gets noisy afterwards.
Voltages look OK:
Cathode 1 (pin 8) = 0.018V
Grid 1 (pin 7) = -0.73V
Anode 1 (pin 6) = 7.35V
Heater 1 (pin 5) = 12V
Heater 2 (pin 4) = 0V (GND)
Cathode 2 (pin 3) = 0.017V
Grid 2 (pin 2) = -0.72V
Anode 2 (pin 1) = 7.35V
Checked for solder bridges, all wiring double checked... >:(
Quote from: JRM on February 05, 2016, 05:13:02 AM
>:(! I'm getting an annoying hum in my Valvemaster! The signal is ok until the valve's first stage but it gets noisy afterwards.
Voltages look OK:
Cathode 1 (pin 8) = 0.018V
Grid 1 (pin 7) = -0.73V
Anode 1 (pin 6) = 7.35V
Heater 1 (pin 5) = 12V
Heater 2 (pin 4) = 0V (GND)
Cathode 2 (pin 3) = 0.017V
Grid 2 (pin 2) = -0.72V
Anode 2 (pin 1) = 7.35V
Checked for solder bridges, all wiring double checked... >:(
Do you have it in a metal grounded enclosure? Mine had a hum too until I boxed it.
Yes, it has a metal enclosure. After several hours of troubleshooting and checking I've come to the conclusion that the hum is induced by the psu. I've swapped it with a 9V/375mA one and the hum has gone. That's very weird as the psu was custom designed with a 15V/3VA transformer, rectifier, large filtering caps and 7812 regulator. It should be ok. And the current should be enough also☹
I've used a probe and the hum starts at the exit of the first amp stage. Before that it's quiet.
Glad you got it worked out.
No I haven't. It is supposed to run on 12V and with that still hums
Ah. Yes, it does appear to be your 12V PS. Can you post a diagram of the PS with cap values?
There she is, my PSU:
(http://imagizer.imageshack.us/v2/150x100q90/924/eQCdis.jpg) (http://imageshack.com/f/poeQCdisj)
(http://imagizer.imageshack.us/v2/150x100q90/921/IrCigC.jpg) (http://imageshack.com/f/plIrCigCj)
Caps are 100uF and 470uF 25V The schem is dead simple: 15V@200mA Trafo to DB102 rectifying bridge, 100uF Cap in parallel, 7812 voltage regulator and 470uF Cap in parallel at exit. As I wanted to have 12,6V I've added a 4001 diode between the 7812 and the ground. Already tested without the diode and it's the same. What's driving me nuts it's that the 9V that doesn't hum is the one on the right, the parts and schem are the same except the trafo (12V@375mA) and the regulator (7809).
And my Valvemaster:
(http://imagizer.imageshack.us/v2/150x100q90/924/a8JmfP.jpg) (http://imageshack.com/f/poa8JmfPj)
The disconnected wire is the LED ground in a desperate test to discover what is causing hum. It's not the led...
Ground is not in a perfect star grounding but almost: a wire goes directly from the power jack to the valve socket (pin 5) and another to the input jack where the other ground connections needed go...
jrm - on your humming trafo/reg combo - can you put your audio probe to the DC into the reg, and then the DC out of the reg? does either point humm?
and what is the measured DC voltage into (and out of) regulator on the humming combo?
I agree with Duck's advice.
The Fairchild data sheet shows a o.33 uf cap on the input and a 0.1 uf on the output. I've seen examples where you have two or more caps on each end. There's a reason for this, but someone else smarter than I will have to explain it.
I would experiment with smaller caps in parallel with the other caps and see if that helps. See if you can temporarily hold the leads of the smaller caps against the leads of the caps on the board to see if that makes a difference. Be careful not to cause a short across the caps if you do this.
If this doesn't work, maybe breadboard or knock up a new circuit using smaller caps. Someone else should be able to chime in with more advice on the caps.
DC voltage before the regulator (no load/full power)= 33.8V/14.8V
DC voltage after the regulator (no load/full power)= 11.95V/11.8V
I think the problem is that the no load condition ruined my first filtering cap! It has a 25V rating and got a much higher voltage that ruined it. I've tried to put several caps in parallel with the out cap and no improvement achieved but a 220uF 50V cap reduced the hum and was just being hold in my hand, not soldered.
Quote from: MasaRGR on December 11, 2007, 11:37:09 PM
Quote from: dano12 on December 11, 2007, 07:51:24 PM
It appears Matsumin's site has gone 404'd on us, but here is my redrawn schematic with a few cap substitutions.
He moved his site recently to a new address http://www.matsumin.net/ (http://www.matsumin.net/)
Thanks for the schematic! Looks like fun :)
Hi, I need help, I can not find any schematics. I do not know where it is located.
Can someone send me a direct link to the schematic or just post a pdf of it?
Thank you.
it's only 181 pages to look thu, finom, don't you have any spare time?
here is "a" version of the circuit, modified from the beavis diagram. I take no responsibillity for its accuracy.
(http://i.imgur.com/G6xiWAv.gif)
Quote from: duck_arse on February 17, 2016, 08:36:28 AM
it's only 181 pages to look thu, finom, don't you have any spare time?
here is "a" version of the circuit, modified from the beavis diagram. I take no responsibillity for its accuracy.
(http://i.imgur.com/G6xiWAv.gif)
The diodes are the only thing added there, other than that it's the original schematic.
It's rockin'!!! I've replaced the 100uF/25V on the PSU for a 220uF/35V and the hum was gone. Now I can fine tune the beast. I might switch again that first cap to a bigger 1000uF (must buy it) as I saw on Tube Town's Banana Booster and/or the second cap to a 2200uF sitting at my parts drawer.
Regarding the pedal's sound I dig it! I'll add a resistance between the gain pot and ground as I don't like that the first half of the travelling adds so little boost/gain (it's a log pot but...). I'm thinking of adding a 50 to 75k resistance in order to set the minimum gain. Another twicking is the tone stack: never liked it much but don't know what fit's better in this circuit: either a Stupidly wonderful tone control (MH original or Jack Orman's variations), a Big Muff tone stack or something else. Another idea is to change the place of the tone control from the exit to before the gain pot as it might affect the tone more effectivly.
Time, I need time!!!
Or, better still, remove the tone control completely. On each of my builds it was superfluous and removing it gives you a little extra something
Glad you've got yours working
Hi everybody!
Before all I need to sorry, because my English is very bad :icon_biggrin: , but I think that everybody can understand me.
I build Valve caster on USSR 6n23p tube. But when I try to check and connect my phone to IN and press "play" I don't hear anything on out(connected 8ohm, 0.5 W speaker! Its only 0.26V on OUT. Please help me!! :icon_sad:
Quote from: gikai on March 22, 2016, 04:18:38 AM
Hi everybody!
Before all I need to sorry, because my English is very bad :icon_biggrin: , but I think that everybody can understand me.
I build Valve caster on USSR 6n23p tube. But when I try to check and connect my phone to IN and press "play" I don't hear anything on out(connected 8ohm, 0.5 W speaker! Its only 0.26V on OUT. Please help me!! :icon_sad:
Which layout did you use? Pics of your build? Are you running the valvecaster into an amplifier or just trying to run it straight into a speaker? If you're plugging your phone into it how do you have it hooked up?
Welcome to the forum by the way ;D
I think he meant phone jack which is an old name for the 1/4" guitar jacks we use. They were originally used for phone switch boards.
It sounds like he's running the output to a speaker.
Quote from: Jdansti on March 23, 2016, 09:07:15 AM
I think he meant phone jack which is an old name for the 1/4" guitar jacks we use.
But he said "connect my phone to IN and press play," which leads me to believe he's trying to use it as a stereo amplifier.
Clarification gikai? :)
I interpreted "press play" as pressing the stomp switch. I'll shut up now and let him speak for himself. :-X :)
I'm sorry, because I show myself like a stupid :)
I forget, that tubes have high output impedance. When I connect output to headphones I hear "Sweet victory" in my head! It works (my first working project :) ). I near time i will post 3D printed box for Valvevaster
I did not think that someone will respond at all to my cry for help , lol
There are no stupid questions here! Glad it works! Looking forward to seeing your enclosure.
Would it be possible to add a balanced line out to this circuit? That way I wouldn't have to use a di box.
Sent from my iPhone using Tapatalk
So I built this pedal last night. It sounds good but I have a few issues. The tone pot is backwards, can I just solder to the other pin? Also there is a grounding issue I think. As soon as I touch the box, it goes away. Here's a pic of the build too. (http://uploads.tapatalk-cdn.com/20160525/07b1bcfeb897bc9a4fe9a2d01038d46a.jpg)
Sent from my iPhone using Tapatalk
Regarding the tone pot, yes, move C3 to the other outer lug.
Regarding grounding, are you using plastic I/O jacks? If so, connect a ground wire directly to the enclosure.
One more issue. This thing has a nasty hum. As long as your playing its ok but stop and it's overwhelming. I've read some earlier posts about the same hum, but they are mentioning caps that my pedal doesn't have! I have built this exactly like the schematic that duck_arse posted earlier except for the diodes. Is this my problem? Is it maybe the wall wart that I'm using? Any help would be awesome!
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Disregard that last question. It is most definitely the wall wart. I hooked a battery to it and it was gone. I guess I need a better power supply.
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For these, it's best to order a special supply. I snagged one off amazon for $20 or so, a 12v filtered supply. Works great.
I'd suggest changing the gain knob for a real gain knob though.. where it controls the volume between the sides of the tube. Sounds much better than the bias knob it currently is.
So many question, so little time. Could I run this on 12v? How would I hook up that gain pot? I'm a total noob bro! Thanks
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crane - look very carefully at the nameplate on your buzy supply. give us the ratings, please, it may be you are overloading it some. or is it an AC output? nah, couldn't be, surely.
and if you are using 12A*7 valve/s, they are meant for 12V (or 6V) heater supply.
Yes I'm using a 12au7 valve. The power supply is just one I had laying around from something else. I don't even know what it was for! I powered another pedal with it and it hummed too.
(http://uploads.tapatalk-cdn.com/20160529/d8d64129cbd660e05c4751ebc3d73abc.jpg)
I ordered a filtered supply this morning.
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well, it says DC, so probably it just needs some extra filtering. but not for this valve project. if you have a 12V DC supply, also laying around, try that.
More voltage sounds more better for this... Definitely worth the hassle. Theres a vid on youtube somewhere where you can hear the difference.
About the gain pot, I posted it a few pages back. Sounds so much better.
If I run 12v, I can keep the same caps and resisters?
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Yep, you're good.
Rookie mistake. I found a 12v supply, plugged it in and Pop! Didn't check polarity. Dang. Did I just ruin this valve or just one of the caps?
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Quote from: cranedewd on May 29, 2016, 03:14:12 PM
Rookie mistake. I found a 12v supply, plugged it in and Pop! Didn't check polarity. Dang. Did I just ruin this valve or just one of the caps?
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Probably just a cap. Valves tend to be pretty resilient and forgiving of (most) mistakes.
You should add reverse polarity protection... Just in case.
Guys, I'm at a loss. I greatly appreciate all your help, but I just cannot figure this out. I bought these sockets for my power supply to the box.
(http://uploads.tapatalk-cdn.com/20160530/f85faa2c2112ad4071c91baf694ef1c5.jpg)
When I mount the socket to the box and plug in the power supply, nothing happens. If I remove the socket from the box and plug it back in, it works! I don't get it. Thanks for any suggestions.
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Quote from: cranedewd on May 30, 2016, 12:46:00 AM
Guys, I'm at a loss. I greatly appreciate all your help, but I just cannot figure this out. I bought these sockets for my power supply to the box.
(http://uploads.tapatalk-cdn.com/20160530/f85faa2c2112ad4071c91baf694ef1c5.jpg)
When I mount the socket to the box and plug in the power supply, nothing happens. If I remove the socket from the box and plug it back in, it works! I don't get it. Thanks for any suggestions.
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That will be your problem. Metal jacks mounted on a metal box is going to create problems. We use center negative sleeve positive on our power supplies for pedals, but by convention audio jacks are opposite. So you're connecting the ground to the metal box through the input/output jacks, then you're connecting 9V DC to the metal box through the power jack. This is a problem :)
...in other words, you're shorting out your power supply. You can try to insulate the jack, or else get a plastic one.
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What they said-like this.
http://www.taydaelectronics.com/dc-power-jack-2-1mm-enclosed-frame-with-switch.html
Quote from: cranedewd on May 29, 2016, 09:15:26 AM
So many question, so little time. Could I run this on 12v? How would I hook up that gain pot? I'm a total noob bro! Thanks
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The circuit will run without modification on a 12V supply. I run mine on an 18V supply, and the only mod for that is adding a resistor in the heating circuit. (You can run these valves with 18V through the heater, but their lifespan will stink.)
Actually, truth be told, if I were running the circuit on 9V, I'd modify it to run the heaters in parallel, and put a resistor in to drop the voltage to 6V.
Could I use a 12ax7 in this pedal? How would it sound?
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I think the general concensus is that 12ax7's don't work as well but my experience is that old ones do. Brimar, Mullard etc sound pretty good but newer valves really need higher voltages.
Quote from: stallik on May 31, 2016, 06:15:30 PM
I think the general concensus is that 12ax7's don't work as well but my experience is that old ones do. Brimar, Mullard etc sound pretty good but newer valves really need higher voltages.
Agreed. I've tried older Mullards that still sound good, but I've tried brand new Sovteks and JJ's that sound awful.
Quote from: vigilante397 on May 31, 2016, 06:45:18 PM
Quote from: stallik on May 31, 2016, 06:15:30 PM
I think the general concensus is that 12ax7's don't work as well but my experience is that old ones do. Brimar, Mullard etc sound pretty good but newer valves really need higher voltages.
Agreed. I've tried older Mullards that still sound good, but I've tried brand new Sovteks and JJ's that sound awful.
JJ does a terrible job of doing tube burn-ins. Their 12AX7's sound terrible in
everything until you've run them about 10 hours.
You guys have been really helpful and I appreciate it. Next question. If I have a 3pdt switch can I use it as a standby switch with the LED circuit? If so, where do I put the switch in the circuit? One more, is it necessary? Thanks in advance.
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You want an LED that lights up to tell you the unit has power, and another to tell you the drive circuit is engaged?
The LED is not really necessary. Could I just use that part of the switch as a standby switch. If I could keep the LED too that would be cool but not the biggest deal if not. I guess the thing I need to know is where would I put the standby in the circuit?
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Quote from: cranedewd on June 01, 2016, 10:21:28 AM
The LED is not really necessary. Could I just use that part of the switch as a standby switch. If I could keep the LED too that would be cool but not the biggest deal if not. I guess the thing I need to know is where would I put the standby in the circuit?
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By standby, do you mean bypass?
The way you wire these, the heater circuit on the tube is not switched. If the pedal is plugged in, the heater is on. You use the 3PDT switch to switch between effect and bypass, and between LED on and off (or if using 2-color LED's, which is not common, between color 1 and color 2.)
I meant standby. I know tube amps have standby switches, just wondered if this needs one too.
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I think, if you search PRR's posts for the last couple of months, or maybe in this thread even, he gives some of the reasons for 12AX7 being not best suited to this type low-volts circuit.
[edit :] here and here:
http://www.diystompboxes.com/smfforum/index.php?topic=103881.0
http://www.diystompboxes.com/smfforum/index.php?topic=112782.0
Quote from: cranedewd on June 01, 2016, 11:05:26 AM
I meant standby. I know tube amps have standby switches, just wondered if this needs one too.
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Oh, ok. No, they're not usually built with one.
The standby on an amp turns on the heater circuits of the tubes, while disengaging the audio circuit. This prevents wear-and-tear on the power section of the tubes.
In practice, the benefit is infinitessimal.
It's not necessary here, because the tube life of 12A_7 is very long, and the power you're supplying to the power section is not substantial. Typical service life is nominally in the ballpark of 9000 hours. Even with the suboptimal build, running the heater at 9V, you'll get more than half of that. You could play over an hour a day and only have to change tubes once every two years, at most.
Last night I took this pedal to band practice at church. I ran through a volume pedal to the valvecaster then to a direct box. I play bass so I am really just kinda looking to use this for a good tube sound. There wasn't nearly enough signal. We use in ear monitors and with the rest of the band playing I couldn't barely hear myself. Should I use a signal boost? I've seen a couple people that used 2-3 tubes in a valvecaster pedal. Is this what I should do? Thanks
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Quote from: cranedewd on June 02, 2016, 08:11:21 AM
Last night I took this pedal to band practice at church. I ran through a volume pedal to the valvecaster then to a direct box. I play bass so I am really just kinda looking to use this for a good tube sound. There wasn't nearly enough signal. We use in ear monitors and with the rest of the band playing I couldn't barely hear myself. Should I use a signal boost? I've seen a couple people that used 2-3 tubes in a valvecaster pedal. Is this what I should do? Thanks
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Ok--question 1--Are you getting a volume
drop, or just not much boost.
Question 2--Did you use the default capacitors?
I'm not sure about a volume drop. Yes I used all default caps.
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Well, the pedal is designed for guitar, so the caps are chosen for that frequency range. I'd have to math it out, but I suspect that your 47nF caps may all need to be larger. If I get a chance to do said math today, I will, but that could be problem #1.
Do you have a guitar you can try the pedal with? If so, let us know if works as desired.
Yes I've played a guitar through it and it seemed to have plenty of signal. The bass I'm playing is a 5 string Schecter with a preamp if that helps.
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I let a guitar player friend of mine borrow this pedal to get his opinion of it. He says that he wasn't getting good lows or mids. I built it exactly like the schematic said. What caps would I change and what would I change them too?
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anybody know how to make a 60 volt power supply with a voltage divider for 12 volts to power this?
It's mostly been done the other way 'round - 12 volt heater supply with a voltage multiplier or charge pump arrangement to boost voltage for the plates. Do a search for them...Renegadrian did a voltage multiplier or two, and I think Frequency Central posted a charge pump layout.
Quote from: PaulBass on October 16, 2016, 03:47:14 PM
anybody know how to make a 60 volt power supply with a voltage divider for 12 volts to power this?
how is the noise on those charge pumps? any hums or hissing?
found it much easier to tap into the secondary 52 & 12v power of the amplifier with 2 conductor shielded cable. problem solved :icon_smile:
Time to give this incredible thread a bump... and a little recognition. Many thanks to everyone that has contributed to this project. I mean.....like...... WOW!
I dont know how the valvecaster eluded me for so many years. I first "discovered" it only a few short weeks ago and I bet I hadnt even made it 10 pages deep into this thread before deciding I needed one and ironically, I completed the valvecaster AND this thread right about the same time. :icon_wink:
I definitely want to explore a few of the valvecaster variations ive read about here but decided to stick to the basics for this first build. I eliminated the tone control and added the treble bleed cap to the gain pot but everthing else was by the book. It was a fairly easy build and it fired up on the first try with an RCA 12au7 installed.
How does it sound?
I own two of the most infamous "clean" amps known to mankind... One is a 68 Bandmaster and the other is a 78 Twin. The VC matches up to them both very well. VERY well...
Then I tossed in my Aqua Puss clone and NPN boost....
Unreal.
(http://www.mylespaul.com/forums/picture.php?albumid=4869&pictureid=81526)
Quote from: PaulBass on October 16, 2016, 05:13:35 PM
Quote from: PaulBass on October 16, 2016, 03:47:14 PM
anybody know how to make a 60 volt power supply with a voltage divider for 12 volts to power this?
how is the noise on those charge pumps? any hums or hissing?
In the 40106 one, nothing bad to report - in the 555 smps, it depends on many factors, like type of inductor, type of 555 ic, etc. - I built a couple and one type of inductor (the green "resistor-like" type) just burned in a few moments - the black "electrolytic-like" type seems stronger. as you americans say, your mileage may vary.
Quote from: rutabaga bob on October 16, 2016, 04:14:46 PM
Renegadrian did a voltage multiplier or two.
I have to be honest on that, I just made some layouts I posted and shared here but the projects they come from are not mine. I always give credit on my images where needed.
Quote from: cranedewd on June 02, 2016, 08:34:35 AM
Yes I've played a guitar through it and it seemed to have plenty of signal. The bass I'm playing is a 5 string Schecter with a preamp if that helps.
I sometimes used a toneless valvy with my bass, got good results with it, I tell you I prefer to use it with bass than with guitar. It always gave me a good boost both in volume and in "air", fat sound garanteed. maybe it doesn't match well with the bass internal preamp!?
I will try to make this kind of power supply for my Valvecaster: I plan to use 9V supply, then to make 2x 6V for heater using two of 78L06 (very cheap and providing just enough power for one half of heater), and I will push 9V to 40V using MC34063A charge pump. Any thoughts about this idea?
:icon_mrgreen:
(http://i64.tinypic.com/sd07q1.jpg)
I've used all types of voltages but you really hear its full potential when you're at 36v and above. at 50v the sound is killer
"Full potential". I get it!!!
Quote from: PaulBass on February 12, 2017, 04:37:35 PM
I've used all types of voltages but you really hear its full potential when you're at 36v and above. at 50v the sound is killer
For bass or guitar use?
Quote from: PaulBass on February 12, 2017, 04:37:35 PM
I've used all types of voltages but you really hear its full potential when you're at 36v and above. at 50v the sound is killer
Keeping the heaters regulated much lower though, of course. 8) Running a higher plate voltage will always get your more of that typical valve sound, otherwise our amps would run off 9V supplies. The whole idea behind the creation of the pedal (in my humble opinion) was not to make the best sounding tube preamp in the world, but to make something that sounds pretty darn good with what is generally considered an absurdly low plate voltage.
Using a SMPS to boost the 9v is a good idea, with very nice results in mini amplifiers.
I used a 555 to boost the voltage to 250v in a preamp using the ef184 tube.
The thing with smps is that they're very sensible to layout and components. A cheap inductor will introduce some switching noise.
But there are a lot of different configurations. With the icl7660s you can build a charge pump that would easily deliver 50v without the inductor.
At lower voltages adding a transistor to the plates also works as an improved anode resistor.
I don't like 7660, it has very low working frequency. Inductors are not a big issue - they are small for currents needed for tubes. What do you think about using two 78L06 for powering heaters in parallel?
Quote from: rankot on February 14, 2017, 03:05:12 AM
I don't like 7660, it has very low working frequency.
Quote from: thomasha on February 13, 2017, 01:18:11 PM
With the icl7660s . . .
The 7660
S has the high-speed boost option.
Bump
Hi guys, im new here.
I am building a hybrid amp of which the preamp is based on the valvecaster, modded and upgraded to within an inch of its life. On certain guitars it kinda farts out a bit when the gain is up, i suspect its an overload of mids hitting the tubes. The bass cut pot prevents this (cuts everything below 750hz by -3db/octave), but it also cuts out the bottom end, which makes it sound thin. Now for my question, how can i reintroduce the bass in my signal??
Quote from: iainpunk on December 19, 2017, 10:47:01 AM
Bump
Hi guys, im new here.
I am building a hybrid amp of which the preamp is based on the valvecaster, modded and upgraded to within an inch of its life. On certain guitars it kinda farts out a bit when the gain is up, i suspect its an overload of mids hitting the tubes. The bass cut pot prevents this (cuts everything below 750hz by -3db/octave), but it also cuts out the bottom end, which makes it sound thin. Now for my question, how can i reintroduce the bass in my signal??
Welcome to the forum :)
Your question is a tricky one: "I'm taking all the bass out of my signal, how do I put it back?"
The Valvecaster is a pretty dark-voiced pedal, the fartiness you're hearing has nothing to do with what the tube is taking in, it's all going to be on the output. The 12AU7 has a pretty wide frequency response. I would recommend looking at a different tone stack for the Valvecaster stage and see if you can get the tone you're looking for. Good luck! ;D
Quote from: vigilante397 on December 19, 2017, 01:24:48 PM
Quote from: iainpunk on December 19, 2017, 10:47:01 AM
Bump
Hi guys, im new here.
I am building a hybrid amp of which the preamp is based on the valvecaster, modded and upgraded to within an inch of its life. On certain guitars it kinda farts out a bit when the gain is up, i suspect its an overload of mids hitting the tubes. The bass cut pot prevents this (cuts everything below 750hz by -3db/octave), but it also cuts out the bottom end, which makes it sound thin. Now for my question, how can i reintroduce the bass in my signal??
Welcome to the forum :)
Your question is a tricky one: "I'm taking all the bass out of my signal, how do I put it back?"
The Valvecaster is a pretty dark-voiced pedal, the fartiness you're hearing has nothing to do with what the tube is taking in, it's all going to be on the output. The 12AU7 has a pretty wide frequency response. I would recommend looking at a different tone stack for the Valvecaster stage and see if you can get the tone you're looking for. Good luck! ;D
Hey, i found the problems solution, the farting out was due to an abundance of low mids, so i changed the caps and resistors i had going on in between the stages, this cuts out the farty mids a lot. Still a mid-rich sound, but not so over done and farty like it was. (If you look at a fender or marshall preamp frequency response, they both cut out a lot of mids, mine does less so). At first i wanted to keep the elaborate tone circuit i had going on in between the stages, but after minimizing and redoing everything, it sounded great. Il post a schematic for the preamp when i find a way to make them on my phone. (Any suggestions?)
Iain
The schematic after some simpifying the tone stack (im to lazy and frustrated with the program to make a "before" schematic). There were no tube symbols, i hope these squares are sufficient.
(https://s13.postimg.org/7ch23hqsj/Screenshot_20171219-232754.png) (https://postimg.org/image/7ch23hqsj/)
I left out the heater, but its supply is the same 12v supply as the rest.
Iain
"Classic" guitar input uses 12AX7 at 300V. Will take over 0.5V peak from guitar without rude noises.
ValveCaster 12AU7 at 12V, input overload may be 0.15V even 0.1V. Will overload on signals that an old Fender will pass clean.
The today-answer is to turn-down the guitar, turn-up after the ValveCaster.
But that gets you closer to Universal Hiss.
Quote from: PRR on December 19, 2017, 07:39:32 PM
"Classic" guitar input uses 12AX7 at 300V. Will take over 0.5V peak from guitar without rude noises.
ValveCaster 12AU7 at 12V, input overload may be 0.15V even 0.1V. Will overload on signals that an old Fender will pass clean.
The today-answer is to turn-down the guitar, turn-up after the ValveCaster.
But that gets you closer to Universal Hiss.
Or, you lower the gain of the first stage and put a gain control (volume pot) in between stages (instead of the awful bias control) and make the second stage higher gain, so the gain control lets you turn it clean or dirty.
Adding to an old thread here...
6947 tube works in this circuit as well.
You can also use an LM2596 or other high frequency buck converter for the heaters *without noise* and without converting a lot of power into heat.
Hey people,
I have build a Valvecaster and it works great so far.
I have changed the Gain-Control to what @DryRoasted posted here https://www.diystompboxes.com/smfforum/index.php?topic=63479.msg518438#msg518438 (https://www.diystompboxes.com/smfforum/index.php?topic=63479.msg518438#msg518438)
R2 and R3 are both at 100k to decrease the gain. Input-Cap is at 47nF. I tried lower values, but this cuts the signal too much in my opinion. The VC runs at 12V.
When the gain-pot is turned down completely I still have some kind of overdrive in the lower frequencies especially when playing chords. It's not really noticeable when playing single-notes. Why is that?
When I use the original gain-pot-wiring (connected to pin3 instead of pin7) I don't have that behavior. It's clean. But on the other side I have a lot of noise / crackling when turning the gain-pot which is not the case with the wiring from DryRoasted :-D
Could I just ground both pins and add an amplifying stage in front? Does that give the same results?
Thanks,
Chris
Quote from: FantomXR on May 01, 2020, 09:01:09 AM
...When the gain-pot is turned down completely I still have some kind of overdrive in the lower frequencies especially when playing chords. It's not really noticeable when playing single-notes. Why is that?
Because this modification sounds less cleaner than original. Low frequency signals usually contain more energy, in another words, low string/fret is louder than high string/fret. So when the pickup outputs higher signals like lower string /fret or multiple strings, it saturate while single notes could stay clean.
Quote from: FantomXR on May 01, 2020, 09:01:09 AM
...When I use the original gain-pot-wiring (connected to pin3 instead of pin7) I don't have that behavior. It's clean.
First we have to make clear that gain is one thing, clipping voltage is another, together they create distortion. Only when they are independent to each other and the latter fixed, you can say distortion is related to gain. For instance : diode hard clipping circuits.
So in the Valvecaster design, turning down the gain is increasing the cathode resistance, by this way, we take away voltage from the tube, make it easier to saturate, or you can say lower the clipping voltage.
Noises when turning pot... I'm not sure what caused the difference,but if you have a good pot,it's likely going to be quiet anyway.
Quote from: FantomXR on May 01, 2020, 09:01:09 AM
Could I just ground both pins and add an amplifying stage in front? Does that give the same results?
Yep, you'll need to deal with a lot of low frequency though
wow, weird to read my own post from 4 years ago, fun fact, i just took the tube circuit off of the breadboard last December...
QuoteNoises when turning pot... I'm not sure what caused the difference,but if you have a good pot,it's likely going to be quiet anyway.
that's changing the bias, that always crackles, look at the ''crackle owkay'' knob in ZVex pedals, they change both gain and bias, so it crackles.
the overdrive in the low end when the gain is set low can be an effect of the altered bias, it gets biased lower (current, higher voltage) and closer to the rail voltage/cutoff point this makes hitting that threshold easier. if you change the plate resistor to accommodate for that, it might gate out when the gain/bias is set higher.
i generally don't like the gain/bias control on the original design, instead, i place an input attenuator in front of the first gain stage to set its gain, and just let the tubes do their thing without changing the bias at all.
another trick i like on low voltage tubes is adding a single transistor buffer after the gain stage to deal with the high output impedance:
(https://i.postimg.cc/MnhN7khX/valve-caster-lol.jpg) (https://postimg.cc/MnhN7khX)
this is what i build with a friend of mine,
the one on my breadboard had a big muff tonestack in the feedback loop of the first gain stage and some cross-over distortion diodes in-between the stages, for some subtle ''dirty gate'', to enhance grit and lower the hiss.
you can use a gain stage in front of the tube, as long as you want more gain that it already has, and turn it in to a fuzz!
cheers