I've been looking for another submini amp build, I've breadboarded a few of my own ideas, but nothing satisfied. Today I breadboarded a submini version of Doug H's Firefly using a 6112 and a 7327. I really like it. Very crunchy at maximum volume, and pretty clean with the volume rolled back. The 7327 tube I used is a rare beast indeed, it's a mil-spec replacement for 6111/6021 and capable of handling up to 300 volts on the plates. A 6021WA could be used as a suitable replacement, the WA suffix having higher volatge rating than the standard 6021. At a push I guess a standard 6111/6021 could be used in place of th 7327, though it would be operating outside of it's spec. The subminis are tough little @#$%ers though! If they can be shot out of missiles at 80,000 feet they can handle a few more volts!
I'm using the nixie SMPS to power the amp, which has been posted elsewhere a few times and is based on this design: http://www.ledsales.com.au/kits/nixie_supply.pdf I'm running it with a better inductor than the one listed in the diagram, kindly handmade for me by a friend. My B+ is currently 185 volts.
I'll be building this up into a tiny enclosure over the next week or two, at the moment it's nestling happily on my breadboard! Many, many thanks to Doug H for allowing me to re-draw and post his great design.
(http://i210.photobucket.com/albums/bb292/frequencycentral/Superfly.png)
(http://i210.photobucket.com/albums/bb292/frequencycentral/NixieSMPS.jpg)
Nice project to work on!
Why did you omited the cascode stage?
Any spundclips?
Nice work!
I'n my opinion the cascode is the magic of the firefly (V4).
With the cascode on there is a much better chime to the sound.
More gain for sure but you can turn the gain down and get a nice
slight overdrive that sounds great. For pedal use the non cascode is
better though...
John
Thanks, but I just re-drew Doug's design, so all props to him.
I missed out the cascode because a third tube would have put too much load on my SMPS, and also have added hugely to the current draw, what with the extra heater and all, probably I would have needed to use a wallwart with double the ma to implement it. I'm running it from a 12 volt 500ma regulated wallwart, but I believe the wallwart puts out more ma than it says on the box. Also, Doug stated in the recent thread re. cascode that he thought it's more trouble than its worth. So this little submini version is 'stripped down', if I need boost I have a few pedals available.
I'll do some soundclips when it's built, as it's on two breadboards (one for the SMPS, one for the amp) with the 125A loose, so not easy to move to where I'd need it to be to record it.
Totally awesome Rick! Looking fwd to the sound clips!! :D
Quote from: tranceracer on August 08, 2009, 01:04:16 PM
Totally awesome Rick! Looking fwd to the sound clips!! :D
That should read "Totally awesome
Doug!" All I did was to breadboard it with different tubes. :icon_redface:
Quote from: frequencycentral on August 08, 2009, 11:50:59 AM
I'll do some soundclips when it's built, as it's on two breadboards (one for the SMPS, one for the amp) with the 125A loose, so not easy to move to where I'd need it to be to record it.
Does the SMPS work fine on the breadboard? I dont remember what the switching freq was, but maybe the intercapacitance of the breadboard could bring some troubles
Can't wait to hear how this sounds :icon_biggrin:
I dont quite get the output section of this design. Is this class AB or A?
There is clearly no phase inverter or splitting of the signal prior to the output section. So how does signal get to both output tubes? The second triode's grid is grounded, hmm.
Ideas to increase out...thinking out loud here....
Use pentodes
Use pairs of pentodes, a quad.
Add a bypass cap for that 440R resistor.
selfinverting output: signal for lower tube comes in there through cathode and gets amplified non-inverted, while the upper tube inverts.
Yeah, self split is very neat and efficient isn't it? There's a lot more power here than if the second triode were a phase splitter. I think it would be interesting to try another self split section in parallel with the existing one. More power output at half the impedance? I'll try a bypass cap on that 440R and see what happens. You're right, it would be interesting to try self split with pentodes.
@ snap: you're very knowledgable - why don't we hear more from you? Your posts are always very succinct. :icon_biggrin:
Quote from: kurtlives on August 11, 2009, 11:04:21 PM
Add a bypass cap for that 440R resistor.
I tried a bypass cap, a 33uF was handy, so I tried that. Didn't discern any real difference. And at high volumes it made the whole thing hum - any idea why?
Quote from: frequencycentral on August 12, 2009, 04:38:33 PM
Quote from: kurtlives on August 11, 2009, 11:04:21 PM
Add a bypass cap for that 440R resistor.
I tried a bypass cap, a 33uF was handy, so I tried that. Didn't discern any real difference. And at high volumes it made the whole thing hum - any idea why?
That's weird. Did you notice a shift in frequency when you installed it?
You should have named it the uFly.
(micro-Fly)
Quote from: kurtlives on August 12, 2009, 07:13:08 PM
Quote from: frequencycentral on August 12, 2009, 04:38:33 PM
Quote from: kurtlives on August 11, 2009, 11:04:21 PM
Add a bypass cap for that 440R resistor.
I tried a bypass cap, a 33uF was handy, so I tried that. Didn't discern any real difference. And at high volumes it made the whole thing hum - any idea why?
That's weird. Did you notice a shift in frequency when you installed it?
if you bypass that resistor, you defeat the selfsplit. you might get more gain from the tube with the grid input, but the lower one, the one with the cathode input ( and grounded grid) is basicly silenced..
and besides, ..push/pull amps sound so much better than single ended amps to my ears...
j
Quote from: frequencycentral on August 08, 2009, 11:50:59 AMI missed out the cascode because a third tube would have put too much load on my SMPS, and also have added hugely to the current draw, what with the extra heater and all, probably I would have needed to use a wallwart with double the ma to implement it.
Use a transistor (like the CCS pentaboost, etc.).
Quote from: Johan on August 13, 2009, 01:55:25 PM
Quote from: kurtlives on August 12, 2009, 07:13:08 PM
Quote from: frequencycentral on August 12, 2009, 04:38:33 PM
Quote from: kurtlives on August 11, 2009, 11:04:21 PM
Add a bypass cap for that 440R resistor.
I tried a bypass cap, a 33uF was handy, so I tried that. Didn't discern any real difference. And at high volumes it made the whole thing hum - any idea why?
That's weird. Did you notice a shift in frequency when you installed it?
if you bypass that resistor, you defeat the selfsplit. you might get more gain from the tube with the grid input, but the lower one, the one with the cathode input ( and grounded grid) is basicly silenced...
j
+1!
BTW.: the "Laptube" (http://img.photobucket.com/albums/v437/latronax/2009_6/hac10-2144.jpg)-amp does the auto-phase-inverting with its 2 EL84s
while the 2 ECC83s do a crossover-duty of what the E-H "Hot Tubes" & "Tube Zipper" do elsewhere...
and: the power supply is 2 suited back-to-back 230V:12V transformers... :icon_wink:
the auto-thingy-trick results in a little less output-power...
I wonder if you will show us a schematic...
:icon_rolleyes:
Quote from: puretube on August 13, 2009, 05:19:11 PM
BTW.: the "Laptube" (http://img.photobucket.com/albums/v437/latronax/2009_6/hac10-2144.jpg)-amp does the auto-phase-inverting with its 2 EL84s
I read one of
DougH's posts over at AX84 yesterday, which i think refers to the same thing(y):
"Maybe there's a way to make self-split more efficient. Personally, I like the idea of screen self-split using pentodes."
From this thread: http://www.ax84.com/bbs/index.php?id=333694
A bit of googling turns up these:
http://ax84.com/media/ax84_m141.pdf
http://geckoamps.com/magnatone109/
......which I haven't got time to study right now, but I think demonstrate screen self-split using pentodes.
Quote from: kurtlives on August 13, 2009, 05:20:35 PM
I wonder if you will show us a schematic...
:icon_rolleyes:
Why? haven`t you caught it from this so-called gentleman`s site yet ?:
http://analogguru.an.ohost.de/temp/EH_Tubezipper_factory.pdf (http://analogguru.an.ohost.de/temp/EH_TubeEQ_factory.pdf)
Quote from: puretube on August 13, 2009, 05:59:34 PM
Quote from: kurtlives on August 13, 2009, 05:20:35 PM
I wonder if you will show us a schematic...
:icon_rolleyes:
Why? haven`t you caught it from this so-called gentleman`s site yet ?:
http://analogguru.an.ohost.de/temp/EH_Tubezipper_factory.pdf (http://analogguru.an.ohost.de/temp/EH_TubeEQ_factory.pdf)
Quote from: puretube on August 13, 2009, 05:59:34 PM
Quote from: kurtlives on August 13, 2009, 05:20:35 PM
I wonder if you will show us a schematic...
:icon_rolleyes:
Why? haven`t you caught it from this so-called gentleman`s site yet ?:
http://analogguru.an.ohost.de/temp/EH_Tubezipper_factory.pdf (http://analogguru.an.ohost.de/temp/EH_TubeEQ_factory.pdf)
Oooops.... an error occurred: above link isn`t the T-Z schemo, but
his offering of
his tube-E-Q drawing... (http://img.photobucket.com/albums/v437/latronax/2009_6/anal-tube-EQ-3.jpg)
Here's some soundclips featuring my now almost legendary lousy but highly sought after guitar style:
Signal path:
Squier Telecaster Custom (bridge humbucker) >>> Superfly >>> Shure SM58 >>> >>> Event Gina 24 Soundcard >>> Wavelab
Volume at 12 o'clock:
http://dl.getdropbox.com/u/967492/Superfly%20half%20volume.mp3
Volume at maximum:
http://dl.getdropbox.com/u/967492/Superfly%20full%20volume.mp3
Volume at maximum, with a Big Muff driving the amp (and some genuine submini low voltage feedback):
http://dl.getdropbox.com/u/967492/Superfly%20full%20volume%20plus%20Big%20Muff.mp3
Sounds great.
I'll be watching the pictures thread for your enclosure work of art for the Superfly.
i wont lie, but the sound clips quality are awful .
you must find an other way to record yourself, cause it should has a real good sound there.
I think he gets the point across well. I can still hear the amp's character. Sounding good, Rick. Now if I can just clear my current project list...
(http://i210.photobucket.com/albums/bb292/frequencycentral/100_0111.jpg)
(http://i210.photobucket.com/albums/bb292/frequencycentral/100_0112.jpg)
how much current can you squeeze out of nixie power supply?
cheers
Quote from: bancika on August 25, 2009, 02:16:11 PM
how much current can you squeeze out of nixie power supply?
cheers
I don't know Bane. Certainly enough for this application, but as for numbers I've never measured. I just got a new DMM which I think has a setting to measure it, so I'll look into it. Another SMPS that looks interesting is the one in the Blackstar HT Dual - over at the other forum.
thanks Rick!
Most of them I found are 10-20mA. Typical draw for 6021 triode at 100V is 6.5mA. 6112 draws 2mA per triode IIRC which takes us to 17mA. I hope that model you're using on the other side of the scale :)
Cheers
That may explain one think that was puzzling me. I can get 300 volts out of that SMPS with no load, but when connected to the amp anything over about 210 volts causes it to motorboat. So I'm guessing that as the voltage increases the tubes are asking for more current than the SMPS can supply. I don't know if a bigger value reservoir cap would help any. I settled on 185 volts as the amp sounds good - and loud enough - without having to use physically larger inductors and caps.
I think your work with the sub-minis is way cool.
I too look forward to this ones enclosure as they all have appealed to me so far.
PS I thought it sounded very good as well,you can tell the general tone to be had, probably sound even better with more power.
(http://i210.photobucket.com/albums/bb292/frequencycentral/Superfly001.jpg)
(http://i210.photobucket.com/albums/bb292/frequencycentral/Superfly002.jpg)
(http://i210.photobucket.com/albums/bb292/frequencycentral/Superfly005.jpg)
(http://i210.photobucket.com/albums/bb292/frequencycentral/Superfly006.jpg)
Rick, your work is almost disgusting, it's so beautiful. Meaning: it's so darned pretty that when I look at my own stuff, it makes me want to puke my guts out. It's a kind of art I guess.
Here's the perf layout:
(http://i210.photobucket.com/albums/bb292/frequencycentral/Superflyperf.gif)
(http://i210.photobucket.com/albums/bb292/frequencycentral/Superflyreveal.jpg)
WOW! Another great looking build, man! :icon_cool: I know this thing sounds as good as it looks! Keep 'em comming! ;D
Hey Rick what are you using to make these layouts?
And also your schematics I am tired of drawing mine by hand.
Maybe thats why no-one looks at em.
Quote from: Brymus on August 28, 2009, 10:07:14 AM
Hey Rick what are you using to make these layouts?
And also your schematics I am tired of drawing mine by hand.
Maybe thats why no-one looks at em.
Layouts - DIYLC: http://www.diystompboxes.com/smfforum/index.php?topic=44838.0
I do my schematics in MS Paint.
Hey Thanx Rick,
Using Paint did you just cut symbols from existing schematics or did you find a pack of electronics symbols?
BTW the new pics look sweet.
I was hoping for another light up enclosure this time.
Quote from: Brymus on August 28, 2009, 10:17:11 AM
Hey Thanx Rick,
Using Paint did you just cut symbols from existing schematics or did you find a pack of electronics symbols?
BTW the new pics look sweet.
I was hoping for another light up enclosure this time.
I made some of my own symbols, it's pretty easy, some I stole from data sheets and websites- you can steal mine if you wish!
The light up enclosure were cool but brushed aluminium looks nice - and at ~200 volts those little tubes get hot enough to burn fingers, so I'd be worried about a clear plastic enclosure melting around them. Though that would look good too I guess!
Cool thnx again.
Is the 47uf capacitor (after the B+ and 22k resistor) not needed anymore since you are using an smps? It's not placed anywhere on the perf layout.
Thanks.
-Bernard
Quote from: bbmonster on September 03, 2009, 08:43:29 PM
Is the 47uf capacitor (after the B+ and 22k resistor) not needed anymore since you are using an smps? It's not placed anywhere on the perf layout.
Thanks.
-Bernard
Well spotted! That cap is in the original Firefly schematic to minimise ripples in the B+2. However a 47uF 250v cap was far too huge for my enclosure of choice, so I left it out. Probably bad practice on my part, but I'm still sleeping nights. :icon_neutral:
Rick,
I'm convinced that you shouldn't be getting such a big drop on the B+ side and I still think this is down to the current rating of the 12v supply. The Nixie PSUs place a high instantaneous demand on the supply which is very much higher than the average current draw that you would expect from adding up the current demands of each tube and other associated losses.
Thanks Mick, I'll do some more experimenting. I'm also planning to change out that 2.2uF cap in the SMPS for a higher value. I have another issue which may be connected, if I have the amp at maximum volume (pretty loud!) and use it with a high gain pedal I get some whining, which goes away if I turn the volume down a touch. I haven't forgootten I owe you a couple of NE5532's - the ones I had were bad, so I've ordered some more.
Someone asked by PM for some idea of how big it is, so here's a photo for scale, together with some internationally recognised household items:
(http://i210.photobucket.com/albums/bb292/frequencycentral/000_0009-2.jpg)
Rick , that is one nice piece of kit.
Quote from: Ice-9 on September 06, 2009, 11:00:36 AM
Rick , that is one nice piece of kit.
Thanks Mick - I'm really proud of it too. Definately one of the coolest things I've ever built. With the volume set at 10 or 11 o'clock it's clean and easily loud enough for home use. Cranked it's bloody loud. Cranked with a high gain pedal driving it it's antisocial. Enough to get the steely stare from Mrs FC. :icon_eek:
I'm thinking about building one of these; it looks like it's a very cool little amp. I have a couple of questions that will reveal my noobishness with anything tube.
What power rating do the caps and resistors need to be? Can I just use the regular 1/4w Rs and 16v caps as in pedals?
Where does this fall on the danger continuum between stompboxes and standard tube amps? "The 200v enough to (sting/hurt/kill)" - please select one. After turning it off and unplugging it and leaving it for a few minutes, is it safe to poke around in there?
Any thoughts on using it for bass? I'm not looking to replace my 100w tube head, but I imagine the stock design might be a tad anemic in the low end since it's meant for guitar.
Quote from: Taylor on September 06, 2009, 04:17:22 PM
What power rating do the caps and resistors need to be? Can I just use the regular 1/4w Rs and 16v caps as in pedals?
All the resistors are 1/4 watt. The 2.2uf cap in the SMPS needs to be 400 volt rated. Other than that, no special requirements.
Quote from: Taylor on September 06, 2009, 04:17:22 PM
Where does this fall on the danger continuum between stompboxes and standard tube amps? "The 200v enough to (sting/hurt/kill)" - please select one. After turning it off and unplugging it and leaving it for a few minutes, is it safe to poke around in there?
(
sting/hurt/kill) - but you'll know about it. It's 200 volts DC though, so it tends to cause you to flinch away, as oppossed to AC which make you hold on. I've never received a shock when fiddling with it when it's turned off though.
Quote from: Taylor on September 06, 2009, 04:17:22 PM
Any thoughts on using it for bass? I'm not looking to replace my 100w tube head, but I imagine the stock design might be a tad anemic in the low end since it's meant for guitar.
I'll try it with bass tomorrow. My bass is active though, so it's output is hotter than average. My initial thoughts would be that crunch that is pleasing for guitar is not neccesarily desirable for bass - unless you wanna sound like Lemmy. Also, the OT, Hammond 125A is a little light at the low end compared to it's bigger brothers in the Hammond range.
Cool, thanks for that detailed reply. I use active basses as well, so that's no problem.
What OT would you recommend? Looking on ebay, it seems like they're all around the same price, so should I just go for the 125D?
Quote from: Taylor on September 06, 2009, 04:58:48 PM
What OT would you recommend? Looking on ebay, it seems like they're all around the same price, so should I just go for the 125D?
I don't know, I'm no expert, though my understanding is the bigger ones have a better bottom end as well as higher wattage rating. Bear in mind the 125D is physically a lot bigger too.
The little 3.5w output transformers sold by RS Components are very good, but perhaps a little too big for the size of enclosure used by Rick. They work exceptionally well in the original firefly and have a good range of impedance combinations. Trouble is with the exposed connections in an 'open' amp.
http://uk.rs-online.com/web/search/searchBrowseAction.html?method=searchProducts&searchTerm=3.5w+transformer&x=0&y=0 (http://uk.rs-online.com/web/search/searchBrowseAction.html?method=searchProducts&searchTerm=3.5w+transformer&x=0&y=0)
I asked OEP for a price to run off a quantity of these with flying leads exiting at the bottom, but they never responded, despite my interest in a production run. Guess they've got too much business to want any more.
Much of the bass also comes down to which speaker you use. For guitar work if you hook one of these up to a Celestion G12H in a semi-open back cabinet the bass and lower-mids are incredible.
Can't seem to find 6021wa or 7327 tubes anywhere. Anyone know a source? Or should I just go ahead with underrated tubes as mentioned in the first post?
Quote from: Taylor on September 08, 2009, 04:12:09 AM
Can't seem to find 6021wa or 7327 tubes anywhere. Anyone know a source? Or should I just go ahead with underrated tubes as mentioned in the first post?
In the UK, both these suppliers have 7327:
http://www.langrex.co.uk/
https://secure25.securewebsession.com/bel-tubes.co.uk/shop/index.php?osCsid=4347fe0759098c28188fd5ed43ba0219
Never used them myself, only came across them recently.
Personally I'd 'risk' underrated tubes - but that's just me.
I'm sorry...if I've missed I apologize. What is the volume pot value you're using here? I'm assembling my Mouser parts list. I've just got to build this thing.
Steph
Quote from: punkin on September 11, 2009, 09:37:31 PM
I'm sorry...if I've missed I apologize. What is the volume pot value you're using here? I'm assembling my Mouser parts list. I've just got to build this thing.
Steph
1M log, it's marked as 'Gain' in the schematic on page 1 for some bizzarre reason that I can't explain right now.
Don't forget a little heatsink for the IRF740, and some thermally conductive paste.
I had an interesting experience with the trimpot last weekend. I was adjusting it, my hand slipped and I somehow put too much pressure on it. The amp started to hum. Debugging showed that trimmer was no longer able to adjust the B+, which was at 270v. I changed out the BC547 for a new one and all was good again. Presumably the pressure I put on the trimpot somehow sent lots and lots of volts to the BC547 and it blew. So it's probably worth socketing the BC547. The BC547 acts as a regulator, momentarily shutting down the 555 when the voltage set by the trimmer is reached, so that a constant voltage is maintained.
Great tips! Thanks!
A guy on another forum did this PCB layout. I haven't gone over it with a fine tooth comb, but it looks to be heavily based on my perf layout. It would be worth checking over thouroughly before anyone builds it.
(http://i210.photobucket.com/albums/bb292/frequencycentral/render20superfly.gif)
^
^
^
Here's the PnP for that PCB layout:
(http://i210.photobucket.com/albums/bb292/frequencycentral/superflyPnP.gif)
What part is "L1"? I can't find anything that is measured in "H" if you know what I mean...
EDIT: Nevermind
Will this do? http://no.mouser.com/Search/ProductDetail.aspx?R=RLH0912-101KBRLvirtualkey65210000virtualkey652-RLH0912-101KBRL (http://no.mouser.com/Search/ProductDetail.aspx?R=RLH0912-101KBRLvirtualkey65210000virtualkey652-RLH0912-101KBRL)
I think that works, but it is surface mount. This is the one I was going to use:
http://no.mouser.com/Search/ProductDetail.aspx?R=RLB0712-101KLvirtualkey65210000virtualkey652-RLB0712-101KL
Looks pretty similar to the one I used, and the one in the photo on the PDF that I got the SMPS schematic from: http://www.ledsales.com.au/kits/nixie_supply.pdf
Got my tubes - Yowza. I didn't realize how truly tiny these guys are. I know they're "submini" but I was expecting something about as big as my pinky.
I ordered an OT15PP from here (http://www.musicalpowersupplies.com/3.html). It's bigger, for better bass response, and it comes with end bells so it's a little prettier than the Hammond 125 series. It's actually a little cheaper too. We'll see how it goes. I'm pretty excited about this project.
I'm planning to put a solid state clean boost with EQ in there, and possibly tack an L-Pad to the end so I can have separate control of preamp saturation, power saturation, and actual volume.
Rick, you mentioned adding another power section in parallel for more output. Have you tried that or do you have any further thoughts on it? I'm definitely interested in a little more clean volume than I think it will have stock. Would it be as simple as duplicating the power section, using the signal at pin 2 of the 7327? I still know next to nothing about tube circuits, so I don't know if buffering is necessary, or...?
I'm guessing the stock SMPS couldn't handle this, so maybe I'd have to wait until Cliff Schect's power supply mentioned in the Subzero thread is working.
Quote from: Taylor on October 05, 2009, 05:27:48 PM
Rick, you mentioned adding another power section in parallel for more output. Have you tried that or do you have any further thoughts on it? I'm definitely interested in a little more clean volume than I think it will have stock. Would it be as simple as duplicating the power section, using the signal at pin 2 of the 7327? I still know next to nothing about tube circuits, so I don't know if buffering is necessary, or...?
I'm guessing the stock SMPS couldn't handle this, so maybe I'd have to wait until Cliff Schect's power supply mentioned in the Subzero thread is working.
I've tried it with single ended designs and it does work, certainly increasing volume. But double the tubes doesn't seem to equate to double the volume. Haven't tried it with a self split design like this one though. I believe that parallel output sections also half the output impedance. Yes it should be as simple as just duplicating the power section and using teh signal at pin 2 of the 7327.
Yeah, it's questionable as to if the SMPS will actually power a third tube - not too sure. I suck at math, prefering to just try it and see if it works, so I don't tend to bother calculating current draw and such. :icon_redface:
BTW - you managed to track down some 7327? Where? How much?
Quote from: frequencycentral on October 05, 2009, 06:17:43 PM
BTW - you managed to track down some 7327? Where? How much?
Nope, I'm going to try 6111 instead, I was just saying 7327 for simplicity's sake, since it's what in the schematic.
I want to add a boost with EQ to this. I've got the circuit all figured out and made a layout, but I began to worry if I'm about to do something stupid...
Will it mess things up if I take the 9v from the power jack to power the opamp in my EQ? In other words, does the SMPS need to be power by its own isolated supply, or can I share 9v between the SMPS and booster?
Also, I'm a little unsure how to hook up my transformer. Anyone know of a calculator for figuring out which taps to use for various loads? This is my xfmr's schematic:
http://www.musicalpowersupplies.com/resources/_wsb_522x355_OT15PP_SELL_SPEC.gif
and I'm using an 8 ohm speaker.
Black to ground, yellow to 8 Ohm speaker "+" lead. Speaker "-" lead goes to ground.
Thanks Cliff! Should I use the blue or brown leads on the primary?
That depends, what does the actual design call for? A higher impedance (the 8k windings) will increase your gain slightly while reducing headroom. If you're going for a dirty sound, try the 8k (brown) leads first.
Ok, cool. It's not marked in the schem, but I'll just try both and see what I like.
Anyone have any thoughts about the power supply issue?
QuoteI want to add a boost with EQ to this. I've got the circuit all figured out and made a layout, but I began to worry if I'm about to do something stupid...
Will it mess things up if I take the 9v from the power jack to power the opamp in my EQ? In other words, does the SMPS need to be power by its own isolated supply, or can I share 9v between the SMPS and booster?
Quote from: Taylor on October 08, 2009, 01:11:35 PM
Anyone have any thoughts about the power supply issue?
QuoteI want to add a boost with EQ to this. I've got the circuit all figured out and made a layout, but I began to worry if I'm about to do something stupid...
Will it mess things up if I take the 9v from the power jack to power the opamp in my EQ? In other words, does the SMPS need to be power by its own isolated supply, or can I share 9v between the SMPS and booster?
I don't think that would be a problem. BTW, you mention 9 volts? Maybe it's not clear on the schematics (because the SMPS schematic says 9 volts), but I run mine from 12 volts. Appears to make little difference to the SMPS, but it does mean that the two tubes heaters in series work nicely. You also mentions using two 6111, you'll find that you don't get so much gain with a 6111 in the preamp position as you would with a 6112 (gain of 20 versus gain of 70), but a 6111 should work fine in the power section, albeit that it may be 'overvolted', as the 6111's stated max is 150 volts. But don't let that put you off, I have run them at 200 volts.
I'm just getting round to thinking of doing a version using full size tubes but staying with a SMPS, I have 12AU7 and 12AX7 on hand, but am quite tempted by ECC99. I just got the parts to experiment with some different SMPS designs. I think I'd go for the same size enclosure too!
I think there's some confusion because of all the tube numbers being bandies about (the PCB layout specifies different tubes from the ones either of us is using). I am using a 6112 in the preamp and 6111 in the power position, just as you suggest. These were the only usable subminis I could lay hands on that you mentioned would work.
I did notice that you power everything on 12v, but I had planned to use 9v because I happen to have lot of 9v supplies and no 12v. I didn't think this would be a problem since, as you mention, the Nixie supply schem says 9v in. Buuuut, I see your point with the heaters. I'll grab a 12v supply.
I'm pretty close to finished with my build, but I just realized that the IRF740 is backwards in the PCB layout. Rick has it right in his perf layout, of course. I realized this just as I was about to connect the power to my build. No fires yet.
I was going to fix it myself and upload the new file, but for some reason, my DIYLC won't open the file (maybe because I use the Mac version?) so I can't.
I'm getting lots of nasty digital noise, and intermittent signal. I'm sure the signal thing is some bad joint somewhere, but what about the switching noise?
I can hear it sometimes through the speaker and sometimes there's a buzzing coming out of the circuit itself. Also, my nominal 12v seems to fluctuate when I tweak the B+ trimmer. Any idea where I should be looking for the problem here?
If you hear buzzing from the circuit itself instead of out of your speaker, it might be the transformer you are hearing - this would suggest a bad connection from the transformer to the speaker.
Maarten
Hi Taylor - Just curious about your 12 volt supply. Is it regulated? Strange that the 12 volts should fluctuate as you adjust the B+ trimpot. Also, what amperage is it rated at? Mine is 750ma, though I'm thinking of getting a higher rated supply as I think it would give me a higher B+. I've found with that SMPS that it hums if you ask too much of it. With the supply I'm using 190 volts is fine, but any higher and I get hum. I really only get whine if I use a high gain pedal maxed out into the amp, and then only at close to the amp itself being maxed too.
Have you got a heatsink on the IRF740? As without adequate thermal dissipation the MOSFET will heat up and the point at which it introduces hum into the circuit will be lower - which will mean you'll need to lower the B+ with the trimmer. If it's not heatsinked, and with thermally conductive gel, it will evetually burn out I believe.
So, providing the MOSFET is well heatsinked, find a point at which it doesn't introduce hum, then tweak it back by a further 5 volts just to allow to the heat rise from prolonged use.
However, if you're getting switching noise even at low volume there something else wrong somewhere - is the 555's timing cap the correct value?
The intermittent signal would suggest a bad joint as you suggest. Bedtime now in the UK - so until tomorrow!
Anyone found a toroidal transformer for US power as in the YouTube demo? I've been doing some poking around but can't seem to find one. I really like the extra small compact layout.
I bought a new regulated 1amp supply. Finally got sound! Then I got smoke.
I haven't yet figured out what part smoked, but I now have a very smelly broken amplifier. I don't think it's the MOSFET, I did have it heatsinked. Could it be the tubes? You said originally that you thought it was ok to over-volt these 6111 tubes, but now I'm wondering if I've toasted the tube.
I found some 7327 in America, was just about to gripe about 12 dollars per, until I looked on your UK supplier's site, who sells them for 12 pounds apiece, which is like $19. I guess I'll bite the bullet. Hope I find some use for these 6111s down the road...
Probably the inductor, maybe the MOSFET, unlikely the tubes. The best way to set up the SMPS it to make sure it works with the trimpot anticlockwise at its lowest voltage and gradually step it up. Monitor the voltage at all times. Do you have another inductor? Maybe also consider a higher rated one.
I have more inductors, but they're the same. What rating should be upped on it? There's no mention of voltage rating on the datasheet at all. I appreciate your help; I feel bad that, since nobody else has built this, the support can't be spread over many people like with most projects here. I know you've got lots of forums to hit; I see your posts at tons of forums all over the web!
Inductors are usually rated for current as well as voltage. The current rating would appear to be pretty important with this type of circuit, though the inductor I used is a low curent type, and woks well. As you probably know, I'm not an EE, so most of my experience is practically based. I'm using a 700ma power pack with my amp, so I guess there is a set limit there to how much current can actually be drawn through the inductor, given that the tube heaters are drawing 300ma. It might be that my inductor would burn out if I used a higher curent power pack and I set the SMPS to deliver more volts. The way I understand the SMPS is that if you want more volts it wants more current, that's why mine starts to hum if I turn the volts up to 230v - the power pack can't provide the current. So what I'm saying is that maybe (just maybe) your higher rated power supply allows you to pull more current through the inductor than it can handle without burning out. Maybe.
I had the SMPS on breadboard for a good while before I built it into the amp - so I was sure that it's components would work well in the project at the voltage I selected. It may be worth your while doing the same - breadboarding the SMPS on it's own, making sure it all works, then applying the B+ to the amp part of the circuit.
If you look at gut shots of the Zvex Nano Head and the JJS Class A amplifier you'll see that the inductor used in those SMPS's is of a different type - more heavy duty looking, and able to handle more current. I just got hold of some of them for my further experiments with SMPS's to see if I can get more volts.
I'm pretty sure that the limiting factor in these SMPS's is the current capability of the inductor, that's why Im guessing that it's your inductor that smoked. I did manage to smoke an inductor on my breadboarded SMPS (found out it's limits there for sure!). I also managed to burn out a IRF740 by not heatsinking it properly. But the IRF740 just stopped working whereas teh inductor smoke and stank. But hey - this is proper electronics if you run the risk of mild electric shocks and smoke! What fun!
As for me helping out - there would be little point posting a project and then providing no support. So no problem. And your experience once you've got yours working will add to the collective knowledge.
BTW, if you get hold of some 7327's I'd be interested at some at that price. And I'll also take the 6111's off your hands if you end up with no use for them - though they do have some interesting uses if you choose to keep them.
Man, I am getting nowhere with this. It's frustrating, because I have built monstrously more complex things successfully, so I feel like I'm getting whipped by a fuzz box or something. I managed to kill several BC547s by letting my multimeter probe slip and connect the B+ to the base of the transistor.
I now have a working power supply, but no sound. I'm not sure how to debug, since I can't really use an audio probe connected to an amplifier as I do with recalcitrant effects. My scope can't do more than 50 volt signals. How do you debug something like this?
I remembered that I substituted a 470UF for the 330UF cap - C3. I figured this should be fine, am I wrong here? Is that value important?
Quote from: Taylor on October 16, 2009, 06:15:36 PM
I remembered that I substituted a 470UF for the 330UF cap - C3. I figured this should be fine, am I wrong here? Is that value important?
That value is fine - it's anti ripple stuff.
Talk us through it. You replaced the inductor and your SMPS is working and adjustable between about 100v and 200v? You have the full B+ hitting the output tube, and a much lower voltage hitting the preamp's plates? The tubes are glowing, and their heatered powered in series from 12v, with about 6v on the 'centre tap'? Transformer connected correctly?
Yep, I've got all that, and in fact I have sound now, but again the nasty digital noise.
I think I'll buy several different inductors and see if that's what's causing the problem.
What's supposed to happen by changing the B+ voltage? Higher voltage=louder, or...?
Yes, higher B+ equals higher volume. Can you describe the digital noise? Is it present even at lower volumes? The regulated 1 amp supply that you bought - is that a switching supply by any chance? If it is a switching supply it could be that you'd get stange ring mod type intermodulations between the HF oscillator in the power supply and the HF oscillator in the SMPS.
Aha! That's a very clever point I hadn't thought of. Although it doesn't say, and it's the size of a transformer-based supply rather than the "One-Spot-size" of most switching supplies I've seen, it is quite lightweight, too light to have a transformer inside. I think this must be the problem, because at 45khs I shouldn't be able to hear the SMPS of course, but if the 2 oscillators are heterodyning as you say, it would dip into the audible spectrum.
Quote from: Taylor on October 18, 2009, 03:35:44 PM
......but if the 2 oscillators are heterodyning as you say.......
I found this out when I had a 555 based SMPS and a MAX1044 based charge pump on the same breadboard. Sum and difference for sure. Some great swoopy synth noises there though.
Yeah, it actually reminded me of your tube synth you posted here awhile ago, "Crushed glass" I think it was called?
Now on power supply number 3, a robust 1.2A transformer-based thing, I managed to smoke an even larger inductor. It's a 100uh, 1amp rated inductor, looks just like the ones in the ZVex and JJS amps. I had the 1k trimmer somewhere near the middle, not at full voltage. I also bought some 3300uh .5A inductors, because that's what JJS spec'd. I can try those, but I just don't get what's going on here. Apparently the inductance doesn't matter too much here, so the 1 amp 100uh should be fine, right? I realize my supply is 1.2A, but it's not automatically putting out that much current, right?
Edit: tried the other inductor, also melted. ??? :'(
The inductance DOES matter here, although the actual value isn't critical. The inductor in a switching power supply "balances" the inductor by maintaining a specific amount of voltage across that inductor for a certain amount of time for a given peak inductor current. What this looks like formulaically (new word!) is L = (V*S)/I where L is your inductor, V is the output voltage, S is in seconds and I is the peak current seen by the inductor. What this tells you is that for a certain frequency, you have to maintain a certain voltage across the inductor for a certain amount of time for a given current. If you end up losing this balance, be it increasing the current output, changing the on-time or changing the input voltage, it's the controller IC's job to sense that an imbalance has occurred and either increase or decrease the on-time of the switch accordingly. When the switch controller cannot maintain this balance, the inductor saturates and draws too much current so that either the switch will blow or the inductor will burn out (if the IC doesn't blow first).
I think that in your case, you haven't calculated or measured the peak currents seen by the inductor. For the supply I've finally finished designing (I'll post on it soon after more testing), the peak inductor current is MUCH higher than the rated output current - we're talking 2.85A peak inductor current vs. a 50mA output current. The peak currents in your circuit could be much higher than this still! The peak current is dictated by the inductor size where a smaller inductor draws more current. You're going to either need a higher current inductor or a larger value, but remember that a larger value inductor will increase switch stress.
I'm not sure which schematics you're basing your design off of either, I'm just going off of general knowledge. I will say that my new HV supply design is superior to the other designs I've seen so far in that it has pulse-by-pulse monitoring of the output voltage and would shut off (hopefully) before anything blows up. I have no grudge against 555 timer based designs or anything, I just don't know who designed the things or how good of a job they've done on their supplies. I usually don't trust something that I found on the internet until I've done at least some preliminary calculations to ensure that the design is a good/safe one.
I'm hoping to have my supply posted by this weekend, so maybe you can play around with it and give me some feedback. I have a little 1W tube amp already planned out for this supply, so I'm really stoked to get the supply finished finally and tested out in a real application. I'm also going to do a layout for the supply with a huge focus on making everything as small as possible. I'm hoping to find a FET that doesn't need to be heatsinked which would save a LOT of room, or perhaps I can use a DPAK or D2Pak part and mount it directly to the board. Either way, look for my post coming up soon.
Cool, I will be watching for that.
The circuit I've got is just the amp and supply from the first post in this same thread:
http://www.diystompboxes.com/smfforum/index.php?topic=78302.msg644749#msg644749
Strange, I've built this type of SMPS twice now, and breadboarded it a couple of time too. I've only managed to burn out a low current inductor once. I'm feeling for you though - it's a bummer when things like this hold up a build. BTW, that JJS amp posted over at FSB last week also used this SMPS. Anyway, here's my latest version of the SMPS:
(http://i210.photobucket.com/albums/bb292/frequencycentral/000_0002-2.jpg)
I'm a bit weary of placing a standing inductor so close to the switch like that, especially when you're switching such high voltages. Stick an ungrounded scope probe near the inductor and switch to see what I mean - they both throw out a lot of hash. Probably not going to hurt you or anything, just something to be aware of.
Rick, Looks like you've got a 2.5A inductor there, I guess my next try should be something in that area.
Yeah but look at the inductor in my original Superfly build on page 2 - tiny and low current. I did manage to burn one of these out on the breadboard trying for vey high voltage, but that one in my build has been working well for months now.
You can estimate the max inductor current for a certain output voltage by using the formula I = (Vout*Ton)/L where I is the max current, Vout is the output voltage, Ton is the time that the switch stays on and L is the inductance. This is assuming that the inductor current falls to zero at one point (which it should for these Nixie tube 555 based supplies). The Ton parameter is just (1-D)*T where D is the max duty cycle and T is 1/Fs (switching frequency). Do some math gentlemen!
OK oldgravity, your build is bugging me. Please list the parts you used in the SMPS. What layout did you use? Got any photos? Lets get you running.
Hmm, don't know why everybody's calling me that today. Kind of bumming me out, because I don't want FSB guys digging up more of my posts to call me stupid for trying to learn something.
Anyway, don't worry about it. I just discovered that when buying a new roll of solder, I accidentally bought one with a water-soluble flux, and the flux is partially conductive. ::) Although it didn't show up when probing for continuity, I am thinking that the flux is acting like little capacitors connecting all my joints together. I'm going to start over with a new roll of solder. I appreciate you wanting to help me though.
Oh I just read Ton's post, it amused me - but no offence meant, I apologise. I knew you were oldgravity over there anyway. Conductive flux will FUBAR for sure. BTW, is your diode a UF4004 fast recovery type? Is your MOSFET an IRF740? And what layout are you using?
Well, it's no problem, I didn't choose a different name there because I was trying to pretend I wasn't me, I just happened to be feeling that my real first name was kind of dumb the day I signed up for FSB. Since I (like you) have made duplicate posts here and there, the connection's obvious. The problem only arises when some guy wants to make me feel bad, so he digs up my old posts to make it clear how much more he knows about electronics than I. I have much older, much stupider posts here... :icon_wink: I also realized that I had used the name oldgravity for things involving my personal life, which I'd prefer to keep separate from here.
Anyway, yes I'm using a UF4004 and an IRF740, and the layout from page 3 of this thread:
http://www.diystompboxes.com/smfforum/index.php?topic=78302.msg651912#msg651912
Yeah, that place can be a sharkpit. I try to steer clear of the controversy and just use the information (and sell a few amps!). I post stuff to put stuff back in.
I've done a quick check of the PCB vs my perf, they seem identical except the pinout of the IRF740 that you identified. Would be worth your while checking the PCB against the schematic though. This is frustrating isn't it? Have you tried running it at say 100 - 150 volts? The more voltage from the SMPS the lower the current, therefore hum or whine is more likely at very high voltage.
Quote from: frequencycentral on November 06, 2009, 08:42:18 PM
Yeah, that place can be a sharkpit. I try to steer clear of the controversy and just use the information (and sell a few amps!). I post stuff to put stuff back in.
I've done a quick check of the PCB vs my perf, they seem identical except the pinout of the IRF740 that you identified. Would be worth your while checking the PCB against the schematic though. This is frustrating isn't it? Have you tried running it at say 100 - 150 volts? The more voltage from the SMPS the lower the current, therefore hum or whine is more likely at very high voltage.
Man no joke about these supplies being frustrating.. Both of the SMPS's I'm working work great until I start trying to draw about 80% or more of that max power, then the output voltages droop significantly. I can tell on the boost supply (175V one) that the inductors are saturating, they're the only part getting hot, but on the flyback supply I'm working on everything stays just warm to the touch at full-rated power (diodes get some heat but they're fine) even though the output voltage is sagging. I'm really thinking that adding 10-20% to the max power handling of these supplies will fix my problems. Still, what a frustrating couple of designs!
Not to derail but in my quest to gather parts for this project I found a couple nifty looking tube sockets for sub-mini tubes.
http://pacifictv.ca/socket.htm#submin
This one looks particularly interesting for a horizontal mount. http://members.shaw.ca/Ceceg/b8dierc1.jpg
I'm looking for this SMPS for almost a year, I plant to build Headphone Amp using tubes that draw 10mA each.
How much Load (mA) this SMPS can handle ? 100mA ? sure ?
I know anyone have not tried to use as Headphone amp PSU before, how can I "Filter" this SMPS ?
I know you have no problem with Guitar Amp but this Headphone amp is more sensitive ... right ?
which Schematic I should try ? I gotta try.
Cal
Two questions on this:
-Has the PCB layout been verified?
-Where do you get those "U" shaped bars for the top of your enclosures?
I sold my Superfly prototype - I was made an offer I couldn't refuse, (I just started building another) and never used it with headphones, but I'd guess it could run them ok without any modification. A guy over at AX84 made a purpose built submini stereo amp: http://www.ax84.com/bbs/index.php?id=405677
Not sure of the maximum capabilities of the SMPS, I'd guess 50ma but have never tested for that. The max load is also linked to the type of inductor you use and the voltage you run it at.
The PCB layout (not my layout) is closely based my perf layout (which is verified), although the IRF740 on the PCB may be incorrectly oriented - worth checking. I don't know if Taylor ever debugged his build? I'm not aware of any other builds, my prototype may be the only one, until my new one is finished.
The handles are from a DIY home store in the UK called B&Q.
Im in plannig phase for this great amp, I have the tubes, and gethering other parts also for MO amp, also plan to use PCB since its easyer to do, im checking the "99%" correct PCB posted on forum.
Maybe I should wait till another superfly is born :)
Are any changes planned for second one?
Did you concidered to offer PCB's for your amps or maybee a kit. I think most of the people here enoy DIY stuff, becouse its more fun than buy finished product, at least for me :icon_biggrin:
Quote from: frequencycentral on February 10, 2010, 01:09:51 PMI don't know if Taylor ever debugged his build?
Never did, I think it's botched because of this weird solder I used. I set this aside for a while, but was thinking of trying it again. I think the PCB layout is fine, but just double check the pinout on the IRF740 against the schematic.
I hope Rick wount mind posting this, I redraw the superfly schematic without the SMPS, I used IC sockets for tube mounting, that way tubes are not soldered to the board, and could be changed realy easy.
I plan to use already available SMPS supply from here http://www.desmith.net/NMdS/Electronics/NixiePSU.html, since eagle files are already available and just attach it to the amp board, and it should be able to handle more than 100mA current.
Since I'm not really an expert in eagle I'm still struggling with the routing of the amp board.
If someone is willing to help please let me know, I can share the files no problem, I also plan to make a small batch of PCB for out of this (10 boards), this is the smallest batch that PCB makers are willing to do here, so if someone is willing to join with the desing please let me know.
It's cool of you to do boards for people that want them, but if you just want a single board fabbed as cheaply as possible, check out BatchPCB. You can get one board this size for around $30.
true, but the problem is since SMPS is so small and have SMD components on it, I cant make double sided board at home. And the price is the same for 1 PCB or 10 since the PCB shop charges the whole pannel and i can put arround 10 PCB's per pannel, I dont want to sell them to people, it would be "gift" for those who help to make it happen.
Quote from: max30 on March 09, 2010, 05:17:35 PM
I hope Rick wount mind posting this..................
Feel free, it's not really mine to give anyway, as
Doug H already gave
Firefly to the world.
I just made it smaller.Here's my second one:
(http://i210.photobucket.com/albums/bb292/frequencycentral/Oooh.jpg)
(http://i210.photobucket.com/albums/bb292/frequencycentral/Aaah.jpg)
(http://i210.photobucket.com/albums/bb292/frequencycentral/000_0005-12.jpg)
(http://i210.photobucket.com/albums/bb292/frequencycentral/upside.jpg)
(http://i210.photobucket.com/albums/bb292/frequencycentral/downside.jpg)
Quote from: max30 on March 09, 2010, 05:37:03 PM
true, but the problem is since SMPS is so small and have SMD components on it, I cant make double sided board at home. And the price is the same for 1 PCB or 10 since the PCB shop charges the whole pannel and i can put arround 10 PCB's per pannel, I dont want to sell them to people, it would be "gift" for those who help to make it happen.
What I was saying about BatchPCB is they will take Gerber files and produce a pro, double-sided, silkscreened, soldermasked board with through plating for $30. It's the best deal I've found for this. If your 10 boards are cheaper than $30, I'd love to know where you get them. :)
But I applaud you wanting to give the boards away, very kind of you.
Here is the redrawn schematic of the amp section. If someone is good at Eagle routing please give it a go :)
I had no luck with with it yet.
I uploaded the Eagle file here, I hope it works.
//http://www.2shared.com/file/12022710/c6522fed/Superfly-EAGLE.html
I was getting some squealing with my second Superfly at high volumes. The cure was to remove that 470pF cap. Squeals went away totally.
Hi freq, There's something strange I cannot understand in the schematic in the first page..
The OT impedance on the schematic is 22500:8ohm referred to the pins 2 and 5 (as I see from the pics of your build too)
But my 125a connection chart uses the pins 2 and 4 to obtain 22500:8.
the pins 2-5 are for 8200:8ohm in the chart of the transformer label.
So.. Am I right? ???
I noticed that too, but as this is virtually a straight copy of Doug H's Firefly I stuck to the Firefly schematic (http://i238.photobucket.com/albums/ff243/Casey4s/FireFly/FireflySchematic.jpg). I *suspect* the ohmage figure on the Firefly schematic refers to the maximum available from that transformer as opposed to the taps used. Maybe Doug could shed some light on it? The plate resistance of a 12AU7 is 6500 - 7700 ohms, so 8200 is pretty close. The plate resistance of a 6111WA is 4000 - 5000 ohm. So maybe there's a slighly better combination available. I did try different combinations including 2 and 4, with little difference THB. I'm currently building a Superfly with the addition of a tonestack and a master volume. :icon_biggrin:
I ordered a raytheon 6112 for the pre, and a general electric 6021 for the power section from Audiograde,
because I want to try this nice build. I've already soldered all the components in the night.
I used an unlabeled induttance that I grabbed from other stuff. For the truth I have a 100h induttance too, but is a toroidal one and it's a little bigger, and it's a bit difficult to fit in the box.
Yes, I think that I'll mod it with a 1M volume pot too..
I've the 6021 and the 6112 in my hands.. so i can finish my amp now...
Hello... So I'm debugging the superfly ;)
As it was not working at all... I triple checked the layout and the schematic. :(
The voltage remains the same of the input transformer... just a bit higher (about 20v) The trimmer doesn't affect the voltage in any position.
But, I found something strange at irf740.. :icon_redface:
I take a look at the datasheet, and it seems that the irf740 in the perfboard is wrong oriented.
The nixie ps too shows the pins assignment and in that layout too, the irf740 is oriented backward respect your layout..
could you confirm the mistake in your layout? ???
ops.. I'm taking a look at the pics of your superfly and yes, I can see the irf740 turned on the other side... respect the perfboard. so, tomorrow i'm going to turn it..
It's late now.. tomorrow hope to give you some good news.. ;)
The pinout is marked correctly on my perf layout. Not sure if the symbol is the right way round though, that's why I included the pinout - I'm always a little confused as to how to depict tabbed transistors - did I get it wrong? I guess so.......sorry about that....... :icon_redface:
BTW, the pinout on the PCB layout (it's not my PCB layout) is numbered backwards.
In my last Superfly (the red one) I used an IRF840 instead of an IRF740.
Good luck with your debug!
Thanks friend.. yes.. ;) the pinout number are right, but the symbol is backawrds in the perfboard...
No problem, I'm going to rotate the irf740, so I really hope to give you some good news soon.. After a P1ex and a dr504 builds I'm still excited to build something so "miniature" :)
The first mod will be the volume pot and the switch to use ot as preamp (I guess I've to use an 8ohm dummy load)..
but let's go by steps... ;)
good news at half.. ;D
I turned the irf740 180°.. and the power supply circuit is good now..
ok.. The mini amp sounds, but not as expected. the volume is very low, and when i increase the volume the sound begins "farting".. but I think something due to the supply because the sound became unstable, something like a "tremolo" "ta ta ta ta ta ta ta"
When I insert the tubes in the sockets the voltage drops a lot... I tried different adapters.
with a regulated 9v 300mA adapter, and without tubes, I can set the trimmer to be 180/190v, but with tubes I can't reach more than 110/120v at output tube plates..
The pre tube voltage is lower too... about 50v.
I tried also a 13v dc 150mA adapter non regulated, but it happens the same.. and less voltage too.. sound worse..
With a 17v 1A p.supply, I can turn the trimmer up to max 140v at the plates of the output tube...
But here too, when I try to increase the voltage, it become instable..
And of course 17v at heaters is too much... it should be about 6v...
did you have any similar issue before?
ops.. I think i've found the exact word to define better the problem... ;D I didnt' know before.. :icon_redface:
"Motorboat" ;)
I read again the whole thread because i remembered something about the voltage issues somewhere inthere.
Finally, I think I should try another inductor. the actual one is a toroidal of about 100uH 1A..
The other one was a smaller one, I don't know the value, but it has tight lead (about 1mm).
I tought to try the irf840 too, but i guess that the real difference is only the max voltage driven.
And I guess I've to find a 12v regulated power supply to keep the heaters safe...
I've had no issues with either of my builds, with both I was able to dial in over 200v with the tubes in the circuit. I settled on 185v as being optimal as the smps causes a small hum after some time of running at 195v, this disappears at 185v.
With my second Superfly I tried some different inductor values, 68uH and 150uH, as well as a large 100uH 2.5 watt. , there were issues with all of these, but it seems to like these little 100uH a lot: https://www.rapidonline.com/productinfo.aspx?&tier1=Electronic+Components&tier2=Inductors+And+Chokes&tier3=Leaded+Inductors&tier4=Low+current+radial+lead+inductors&moduleno=64730&catref=88-1630
I'm not sure if your IRF would have been damaged when it was the wong way round?
Something else to watch - my second Superfly I didn't connect the speaker sockets ground to the circuit, just assumed that the chassis would ground it. I had some issues which were solved by groundng the input socket to teh output socket.
Not sure what else to suggest, both my builds have worked without issue. I can only suggest that the circuit may be picky about the exact inductor, and of course a good well regulated 12v power supply, mine is only rated 500ma but is rock solid at 12v.
I should have Superfly #3 build next week, now that the planes are flying again and my Banzai order gets though - they turned down my motorcycle courier suggestion.
Quote from: frequencycentral on April 23, 2010, 03:10:09 PM
I should have Superfly #3 build next week, now that the planes are flying again and my Banzai order gets though - they turned down my motorcycle courier suggestion.
I thought all deliveries in the UK were by umbrella?
(http://wearegroup3.files.wordpress.com/2009/02/mary-poppins-mv03.jpg)
Surely this mode of transport is exempt from volcano grounding?
ok, I tried a similar inductor, so the situation is better than before..
The volume increased a bit, but the motorboating is still there.. and I cannot reach more than 130v..
I tried a 7812 (to220) to try a regulated supply from the 15v adapter.
(without load the voltage is 10,5... i tried different is's too.. maybe I need a cap as stabilizer)
so, after a minute of use, i fried the 7812.... ??? what happened? it seems the amp ask more than 1A current?
But there's a thing I can't understand...
The 12v should be good for the heaters right?
ok, i was expecting that the voltage was a bit balanced between them, I found instead that the first tube has 7,5v at pin3, and about 3,5v at pin3 of the output tube... (i cannot measure the other pins theyre behind some other wires)...
What' happening??? ???
Here's my #3, Superfly Special, with the addition of tone and master volume controls, just finished it. With the tubes in their sockets I can dial in between 125v and 310v.
(http://i210.photobucket.com/albums/bb292/frequencycentral/000_0003-2.jpg)
(http://i210.photobucket.com/albums/bb292/frequencycentral/000_0004-9.jpg)
(http://i210.photobucket.com/albums/bb292/frequencycentral/000_0002-17.jpg)
Here's the schematic of the Special. All I did was remove the grid stopper between the two 6112 stages and replace it with a tonestack, and replaced the 330K grid leak resistor between the preamp and the power amp with a 470k Log pot. The combination of the gain and volume controls is really useful and flexible. The tonestack makes this Superfly not quite as loud as my last two, but a useful addition I guess.
(http://i210.photobucket.com/albums/bb292/frequencycentral/SuperflySpecial.png)
Another engineering masterpiece Rick! :icon_mrgreen:
Now I'd love to see you make one with DM160s. They're so small they make those subminis look like lumbering giants!
Quote from: merlinb on April 24, 2010, 04:29:56 PM
Another engineering masterpiece Rick! :icon_mrgreen:
Now I'd love to see you make one with DM160s. They're so small they make those subminis look like lumbering giants!
Do people use them for audio? It says here it's a voltage indicator:
http://www.r-type.org/exhib/aai0056.htm
Sounds interesting if so, I'm always intrigued by misuse of electronics.
Quote from: Taylor on April 24, 2010, 04:38:41 PM
Do people use them for audio? It says here it's a voltage indicator:
Sounds interesting if so, I'm always intrigued by misuse of electronics.
Yes they became popular in car radios. Plus they light up blue in sympathy with the music, and nothing is cooler than that!
Oh thanks Merlin, I thought I had enough obsessions, and now you find me something else to be obsessed about. :icon_rolleyes: So tell us more about the DM160, are you suggesting using it as a visual thing (very cool - how would one incorporate it?) or do you mean that they could be used as an amp? Their max voltage is 100v, and they're directly heated, so if you did mean an amp it would have to be SE as you couldn't use one for a PI, or self split. I notice there are also Russian equivalents.
:icon_wink:
Nice work Rick... I'm a bit jelous.. I've still troubles with mine..
Maybe i'll do the voume mod when my amp will be fixed.. I want to try another inductor and new ic's before turn on again the beast..
I've seen that the voltage drops a lot after few seconds.. i guessit's because the dissipation is not enough..
wow dm160... :icon_mrgreen: I was trying to stop build fx but... I think we've to inform better about them... I'd like to build something smaller too.... :icon_mrgreen:
but i've to finish the G2 from FSB first.. :P then I think i've to really stop with pedals building.. I'm not playing guitar anymore because i'm spending all my time with fx buildings.. ;D I've built tons of fx but it's time to hear them
Quote from: frequencycentral on April 25, 2010, 07:04:33 AM
So tell us more about the DM160, are you suggesting using it as a visual thing (very cool - how would one incorporate it?) or do you mean that they could be used as an amp?
Well I was suggesting a Superfly variant using the DM160. The fact that they also glow is just a bonus!
They are directly heated, but that shouldn't make things very difficult. PP should be possible with a little lateral thinking. A paraphase arrangement would be possible, if nothing else. i.e., Hang a cap+potential divider off the anode of the output valve that is driven, and use the resulting signal to drive the second valve's grid.
Here's a very crude video of a DM160 frequency indicator I built last week for a forthcoming competition
http://s81.photobucket.com/albums/j207/merlinblencowe/?action=view¤t=CIMG4628.flv&newest=1
After this I will probably dismantle it and try something Superfly-esque with the tubes.
Whoa.
Quote from: merlinb on April 25, 2010, 12:09:10 PM
PP should be possible with a little lateral thinking. A paraphase arrangement would be possible, if nothing else. i.e., Hang a cap+potential divider off the anode of the output valve that is driven, and use the resulting signal to drive the second valve's grid.........after this I will probably dismantle it and try something Superfly-esque with the tubes.
I wanna build one too! I'm ordering a bunch of DM160 right now. Will you share your schematic? :icon_razz:
wow.. it's a cheap tube too.. i can find 4 for 15€ shipping included on ebay ;) ...
the spectrum analyzer is very cool too.. :icon_mrgreen:
Quote from: merlinb on April 25, 2010, 12:09:10 PM
Quote from: frequencycentral on April 25, 2010, 07:04:33 AM
So tell us more about the DM160, are you suggesting using it as a visual thing (very cool - how would one incorporate it?) or do you mean that they could be used as an amp?
Well I was suggesting a Superfly variant using the DM160. The fact that they also glow is just a bonus!
They are directly heated, but that shouldn't make things very difficult. PP should be possible with a little lateral thinking. A paraphase arrangement would be possible, if nothing else. i.e., Hang a cap+potential divider off the anode of the output valve that is driven, and use the resulting signal to drive the second valve's grid.
Here's a very crude video of a DM160 frequency indicator I built last week for a forthcoming competition
http://s81.photobucket.com/albums/j207/merlinblencowe/?action=view¤t=CIMG4628.flv&newest=1
After this I will probably dismantle it and try something Superfly-esque with the tubes.
OMG that is so freakin cool !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
I want an EQ made with those...uhm RICK ?
Quote from: frequencycentral on April 25, 2010, 03:44:34 PM
I wanna build one too! I'm ordering a bunch of DM160 right now. Will you share your schematic? :icon_razz:
Yeah, I'll work something up and post it here. Might give you some ideas regarding biasing the little directly-heated buggers too.!
Ok, here's the gist of my frequency indicator. I'm not saying an audio amp should necessarily use the same approach, but it could work.
I ended up using only 4 inverter stages for the PSU, which gave me about 50V from 12V input, but for audio I guess all six would be preferable (it's a hex inverter chip) especially if its to run off 9V, or use Rick's SMPS of course. This circuit runs at about 300kHz, so I guess it won't cause audible problems. ???
(http://i81.photobucket.com/albums/j207/merlinblencowe/DM160/MiniInverter.jpg?t=1272299302)
This shows how all the tubes are biased to about -2V. For audio, to prevent feedback between stages via the heaters, I think you would want to split each grid leak into 2 parts and decouple the junction of the two resistors.
(http://i81.photobucket.com/albums/j207/merlinblencowe/DM160/DM160.jpg?t=1272299175)
In the frequency indicator I just had an opamp input stage which feeds eight low Q bandpass filters http://sound.westhost.com/project63.htm (http://sound.westhost.com/project63.htm) each tuned to frequencies from 50Hz to 10kHz. Each filter then drives a tube.
And here's a doodle of what I was thinking a DM160 Superfly might look like. I've added variable bias for prototyping- I wouldnt expect to use it in the final version.
(http://i81.photobucket.com/albums/j207/merlinblencowe/DM160/DM160Audio1.jpg?t=1272300600)
The DM160 datasheet (http://www.r-type.org/pdfs/dm160.pdf) says each heater requires 1v / 30ma, so if you ran them parallel that'd be 1v / 120ma. I'm calculating a 91 ohm / 1.32 watt resistor (doesn't exist) would drop 12v to 1v. Therefore an 82 ohm 2 watt resistor in series with two 1n4001 (each drops 0.6v) should get very close.
Quote from: frequencycentral on April 26, 2010, 01:25:16 PM
says each heater requires 1v / 30ma, so if you ran them parallel that'd be 1v / 120ma.
120mA, you're crazy man! All that wasted power!
I'm gonna figure out a way to keep the current low, so a 9V battery could be used (and last more than 5 minutes). The output tubes can at least be in series if self-split is used.
Quote from: merlinb on April 26, 2010, 01:29:18 PM
Quote from: frequencycentral on April 26, 2010, 01:25:16 PM
says each heater requires 1v / 30ma, so if you ran them parallel that'd be 1v / 120ma.
120mA, you're crazy man! All that wasted power!
I'm gonna figure out a way to keep the current low, so a 9V battery could be used (and last more than 5 minutes). The output tubes can at least be in series if self-split is used.
Hahaha! 120ma is 30 less than a single 12AU7 @ 12v. :icon_biggrin:
Quote from: frequencycentral on April 26, 2010, 01:36:22 PM
Hahaha! 120ma is 30 less than a single 12AU7 @ 12v. :icon_biggrin:
Pah, we're working on the nano scale now- can't afford that kind of frivolity! Anyway, how much cooler would it be to be battery operated?!
Ok, it can be done with two 1000uF caps. The smallest I've found on Rapid are 12 x 10mm, which I think is actually pretty good.
http://www.rapidonline.com/Electronic-Components/Capacitors/Radial-Electrolytic/85-deg-C-Radial-electrolytic-capacitors/62556
OK, I'm seduced by battery powered pico tube amp. Am I right re the maximum voltage is 100v? If so a SMPS would be overkill as they require a fair amount of milliampres themselves, and would need taming to get down to 100v. So a charge pump would be a better option. I wonder what consumes less milliampres (and takes up the least space), your 40106 pump, a MAX pump (http://www.diystompboxes.com/smfforum/index.php?topic=73222.msg671717#msg671717) or a 555 pump (http://www.diystompboxes.com/smfforum/index.php?topic=80007.msg672937#msg672937) ?
Quote from: frequencycentral on April 26, 2010, 02:07:32 PM
So a charge pump would be a better option. I wonder what consumes less milliampres (and takes up the least space),
Good question. I know mine is at least 70% efficient. It needs fewer diodes and caps, but the chip is bigger, so I don't know which is smaller.
Although, even operating every valve at 100V 400uA is only 160mW. Even with 50% efficiency that's only 36mA from the battery!
At 50V 200uA for every valve the battery current is less than 10mA worst case.
(Plus filament current of course)
I think we're looking at about 1mW audio output power- enough to hear by, and more than enough to drive headphones. How much power do you get from a superfly?
I might try a hybrid at some point and scrap the output transformer.
Well I just ordered some DM160, so I'm ready to go soon. I've got a couple of amps to build first, I just got a commission for a Superfly with master volume, Vox tonestack and a tremolo section. And then my Obsession, when the tube cages (http://cgi.ebay.co.uk/2-Piece-Rhodium-Plated-Tube-Protector-for-12AX7-ECC83_W0QQitemZ300419642779QQcategoryZ39997QQcmdZViewItemQQ_trksidZp4340.m263QQ_trkparmsZalgo%3DDLSL%252BSIC%26its%3DI%26itu%3DUCI%252BIA%252BUA%252BIEW%252BFICS%252BUFI%26otn%3D10%26po%3D%26ps%3D63%26clkid%3D8955198897229021151) finally arrive from HK.
I'm amused that the battery to run the pico amp will be the single biggest component. That and the OT. I'd imagine it's going to end up being the same size as a Superfly, just less room inside. And with the cool blue glow. :o
That 40106 charge pump looks really interesting, never seen one like that before. Might have to give it a try :)
Quote from: frequencycentral on April 26, 2010, 03:19:02 PM
I'm amused that the battery to run the pico amp will be the single biggest component. That and the OT. I'd imagine it's going to end up being the same size as a Superfly, just less room inside. And with the cool blue glow. :o
Yes, in fact the battery is so big I'm wondering if it won't need to go in a bigger enclosure than the Superfly?
Maybe we can find a smaller OT, like a PCB audio matching transformer, and bend it to our needs.
I'm convinced it will fit in the same size enclosure. Take a look at the Superfly gutshots. Have everything in the same place, with the four DM160 in a row sticking out of holes in the top of the box, the battery would be where the knobs are. The (9mm) volume knob on the top of the enclosure at the opposite end to the OT. I'd still use a 125A, as the tubes really need to poke their little heads out to get the best visual effect, so I'm thinking the same roll bars too. It just needs a very compact board layout, my speciality....
Hmm, maybe your enclosures are deeper than mine (25mm). I can't get a PP3 to go in unless it's lying down on its back, rather than on its side, so it takes up a lot of room. Ill be impressed if you manage it!
EDIT: I'm an idiot- batteries do fit edgeways into my enclosures. What a dingbat.
If you kind of squint at this one you'll get the idea: http://i210.photobucket.com/albums/bb292/frequencycentral/000_0009-13.jpg The enclosures I use are Eddystone 111 X 60 X 27mm, batteries do fit in them as shown. Anyway, if you put in the legwork on the circuit design I'll do the layout and drill you an enclosure. ;)
Quote from: frequencycentral on April 26, 2010, 04:31:34 PM
If you kind of squint at this one you'll get the idea: http://i210.photobucket.com/albums/bb292/frequencycentral/000_0009-13.jpg The enclosures I use are Eddystone 111 X 60 X 27mm, batteries do fit in them as shown. Anyway, if you put in the legwork on the circuit design I'll do the layout and drill you an enclosure. ;)
You'll have to wait for any serious stuff on my part, cause the electronics competition is 3 weeks from now. After than I will dismantle it and do some experiments. The only difficulty I see is in making the self split work well. May have to rig up a gyrator in the filament chain to get enough AC impedance.
You gonna include a tone control?
Good luck with the competition. The timing suits me, got oter stuff to build first.
Quote from: merlinb on April 26, 2010, 05:19:33 PM
You gonna include a tone control?
No, too much loss through a tone control if we're talking 100v or less.
I suppose, although the power valves will be just as sensitive, rather than the lower-mu ones you use in the Superfly.
Merlin, can you explain the heater circuit in your schematic on the previous page please, the two npn transistors. Also, do you think we should start a new thread for the 9v DM160 uFly?
These DM160 are seriously small. Left to right, 12AU7, 6111 submini, DM160, LM324 quad opamp:
(http://i210.photobucket.com/albums/bb292/frequencycentral/SMALL.jpg)
standing ovation... :o :o :o :o :o
Quote from: frequencycentral on April 28, 2010, 04:31:59 PM
Merlin, can you explain the heater circuit in your schematic on the previous page please, the two npn transistors. Also, do you think we should start a new thread for the 9v DM160 uFly?
The two transistors are simply a current-limiter, which in this instance will basically act like a constant-current source. The current is 0.6V / R, where R is the base-emitter resistor. So for 30mA:
R = 0.6 / 0.03 = 20 ohms. As for a new thread that's up to you. Probably worth starting one when you actually start fleshing out s proper circuit. Getting the self-split to work would be the first step, IMO.
ok... I'm still trying to fix the amp..
Now I can't get 180v anymore.. maybe the irf is damaged in someway..
Afterwork, I'm going to take another ic, maybe a irf840 (you told me it's ok..)
and some other inductance.. I think I'll solder another breadboard too, to be sure... or maybe I can etch a board from the layout posted in the thread.
I really hope to play with my new amp...
Hi Rick,
I was taking a look at the amp, and I remembered that I used a 1n4007 instead of the ultrafast...
I really wonder if this could be the matter...
Quote from: prnet on May 04, 2010, 11:17:43 AM
Hi Rick,
I was taking a look at the amp, and I remembered that I used a 1n4007 instead of the ultrafast...
I really wonder if this could be the matter...
Oops! A 1n4007 just isnt going to work. It has to be an ultra fast recovery diode, I use UF4004. Also, another guy who built one ended up simplifying the ground connection by adding a jumper from f8 to n8 instead of having the ground go all the way around the board. On my last two I removed C8, which cut out some whine at high volume, and also allows a direct ground trace from f8 to n8.
yes.. I've noted some differences between your bottom amp photo and the layout.. then I've already seen thatif you remove the pf cap you can place a trace direct to ground..
hi again.. just to update my experience.. still the same situation..
I tried yesterday an irf840 and another diode BY..(something.. don't remember)
It seemed it worked better, with more volume, but still far from the result..
I think I'll try now to separate the power section and build the smps. uhm...
the inductor is still getting warm too, while the mosfet seems to be more colder respect to 740?!? :o
it's very difficult to find inductors here, but I don't want to buy one from internet and pay 3€ of shipment for a 1€ component.. damn... :-\
ok, keep the calm... how McGyver would find the solution? (he's got only a knife, a stick, a chewingum, and distilled water) :icon_mrgreen:
Here's one made by
Tilly Dog, posted over at AX84:
QuoteWell, here's more evidence :)
(http://i255.photobucket.com/albums/hh143/werdnayarg/superfly/IMG_0340.jpg)
(http://i255.photobucket.com/albums/hh143/werdnayarg/superfly/IMG_0328.jpg)
I gave up on the tone stack - I could get a weak treble cut/boost with the moonlight stack, but the tone pot on the guitar has much more range. I tried a master volume, and found it *much* more useful. I was only ever going to put two knobs on the box, so went for the gain control and a master volume.
The switch changes the cathode resistor in the 2nd stage from 820R ("Ash") to ~4.7K ("Smoke") - the larger value gives the amp *some* clean headroom and a bit mellower tone, at the expense of some volume. (Centre position of this switch is off).
I had the case a lovely sooth satin black, but the clear-coat I put over the front panel reacted with the paint and crackled it :-(.
Even at 160V B+ this is too loud as a 'bedroom amp' without the MV.
There is still a certain amount of HF noise visible on the scope which is being picked up somewhere in the first stage. I played around with different grounding, etc. but other than moving the input ground as I mentioned before, nothing made much difference - even breaking the ground path to the switching circuit and running a separate ground for it. Nothing is audible, so I decided to leave it alone for now. (I didn't pull the 470p cap).
The guts aren't as neat as Rick's, but then you wouldn't expect that! :P
(http://i255.photobucket.com/albums/hh143/werdnayarg/superfly/IMG_0342.jpg)
It's gone to my 'Official Tone Consultant' (proper guitar player) for a couple of days so I'll let you know what his verdict is when I get it back.
What a fun project, though !
Thanks :)
Andy
Do you know what the amplification factor of the 7327 is? I've been looking at datasheets but they all seem to be strangely missing that information.
The datasheet says 'a direct replacement for types 6111 and 6021', the 6111 has a gain of 20, the 6021 has a gain of 35, that's all I know. :icon_biggrin:
today, while i was rebuilding my P1extreme 19w in a new painted case, I etched the pcb for my superfly. :icon_mrgreen:
So, I can do another try.. hope this miniamp filnally will work.... tomorrow the response... :o
Anyway, the pieces are all new.. so if it won't work, maybe i'll start suspect about the tubes... :-\
maybe i could try with a 12ax7 and a 12au7.... :o
I can always recycle the submini tubes to build a booster, if I'll lost my patience.. ;D But never happened that an fx or an amp has win against me...
with a little of debug everything always worked to me... ;)
New layout. What's changed:
- 470pF cap removed
- Ground trace simplified
- MOSFET orientation corrected
- Decoupling cap added for preamp supply
- Provision for Tilly Dog's bias mod
- Provision for master volume
- 1n4007 polarity protection added
- Fatter traces for fatter tone!
(http://i210.photobucket.com/albums/bb292/frequencycentral/NewSuperflyPCB.gif)
(http://i210.photobucket.com/albums/bb292/frequencycentral/NewSuperflyPnP.gif)
Here my little DiamondG 1W...
http://www.thepiper.eu/?page_id=129
Finally...
still some little problem to solve but it's ooooook! (//)
Hi again, I'm again a bit confused..
I need to jump back of some posts...
I was still unsure about the transformer pinout..
I found today some files about the original firefly schematic and building guide.
(I uploaded the file at http://www.thepiper.eu/files/firefly.pdf )
the schematic and the build guide uses pins 4-2 that means 22500:8 ???
I referenced this schematic: http://www.ax84.com/media/ax84_m276.gif which states 2 and 5 transformer pinouts.The Firefly is a 'classic AX84 project'.
Just looked at the chart on a 125A box,
- 2-4 @ 8R = 22500
- 2-5 @ 8R = 8200
Quote from: frequencycentral on April 13, 2010, 07:22:39 PM
The plate resistance of a 12AU7 is 6500 - 7700 ohms, so 8200 is pretty close. The plate resistance of a 6111WA is 4000 - 5000 ohm. So maybe there's a slighly better combination available. I did try different combinations including 2 and 4, with little difference THB.
Just looking at the chart on a 125A box again, 1-5 = 5600 and 2-6 = 4200. Maybe one of those would suit the 6111WA better.
I suspect the answer can be found one one of the many AX84 Firefly threads.
Quote from: frequencycentral on April 13, 2010, 07:22:39 PM
Maybe Doug could shed some light on it?
I was wondering if the transformer that Doug Hoffman sells would work for this type build. It powers two 12AX7's at 240v from a wall wart.
http://www.hoffmanamps.com/MyStore/catalog/images/IMG_2431.jpg (http://www.hoffmanamps.com/MyStore/catalog/images/IMG_2431.jpg)
http://www.hoffmanamps.com/MyStore/perlshop.cgi?ACTION=enter&template&thispage=Transformers&ORDER_ID=!ORDERID! (http://www.hoffmanamps.com/MyStore/perlshop.cgi?ACTION=enter&template&thispage=Transformers&ORDER_ID=!ORDERID!)
http://www.el34world.com/projects/images/TubePedalSchematic.gif (http://www.el34world.com/projects/images/TubePedalSchematic.gif)
Hey Frequency Central! Congrats on the good build, also congratulations to Doug for the great design.
One question, Have you tried 2 similar circuits with both nixie powersupply, and your voltage multipliers (the ones with diodes, caps and a max1044)?
I wanna check hoe the different voltages affect really the sound...
Thanks!
If I wanted to... could I build the Superfly Special using normal tubes (The 12AX7 & 12AU7) and use the new MAX1771 charge pump to give it a bit more voltage? Anything need changing or can I just sorta... put them in.
(Tube Newb :icon_mrgreen: )
Well... I went over the datasheets of the AX7 & AU7 and other than the pin outs, I see no difference between the schematics apart from dropping the Extra tube and a few minor ammendments... I did draw a schematic but don't really see the point in posting it as i've just changed the pin numbering for the tubes and added the MAX1771 schematic on the same sheet and added a Baxandall Tone Stack rather than big muff... plus it's not really my work.
So unless anyone has any comments on wether it'll work or not and me not wanting to derail this thread from its sub-mini routes, the only question I really have is where can I get a 0R050 1 Watt Resistor? And as the MAX1771 can deliver higher voltages than the 555 is there any harm in upping it to 250V? I see the tubes are rather to 300V on the Plates but only 180V on the Cathodes....
I would think it would be a perfect marriage of the two. You shouldn't have top change anything, just a case of getting the SMPS running right. In fact I'm planning to build a Suprfly using the MAX1771 at some point myself. You can get 0R100 1 watt resistors from Banzai, you could use two in parallel for 0R050, or try 0R100 as the Rsense resistor, I've had good results with that. http://www.banzaimusic.com/Royal-Ohm-0-1-ohm-1W.html
Quote from: zencafe on June 15, 2010, 09:00:07 PM
One question, Have you tried 2 similar circuits with both nixie powersupply, and your voltage multipliers (the ones with diodes, caps and a max1044)?
I wanna check hoe the different voltages affect really the sound...
With the nixie supply you can dial the voltage right down to around 100v if you want to check how a reduced volateg affects the sound.
Quote from: frequencycentral on June 21, 2010, 01:48:54 PM
I would think it would be a perfect marriage of the two. You shouldn't have top change anything, just a case of getting the SMPS running right. In fact I'm planning to build a Suprfly using the MAX1771 at some point myself. You can get 0R100 1 watt resistors from Banzai, you could use two in parallel for 0R050, or try 0R100 as the Rsense resistor, I've had good results with that. http://www.banzaimusic.com/Royal-Ohm-0-1-ohm-1W.html
Aha, Perfect! Cheers Rick!
Hello. The Hammond 125a, is it the 125a or 125ase I need.
Thanks.
I also have several spare 6111wa tubes for UK delivery for £9.00
What spec 12v power supply do I need?
Doh, output is from transformer. :icon_redface:
Quote from: makaze808 on June 30, 2010, 05:10:21 AM
Hello. The Hammond 125a, is it the 125a or 125ase I need.
The OT is a 125A push/push, not the 125ASE which is single ended.
Quote from: makaze808 on June 30, 2010, 05:10:21 AM
I also have several spare 6111wa tubes for UK delivery for £9.00
Tempting. How many?
Quote from: makaze808 on June 30, 2010, 06:49:49 AM
What spec 12v power supply do I need?
I use this one: http://www.maplin.co.uk/Module.aspx?ModuleNo=32746
Hello.
Well I'm towards the end of my build and I'm hoping it sound as good as it looks.
Couple of issues as I work toward switch on.
Does the inductor have polarity?
Regarding the output connections from the tranny is one + going to + on the speaker and the other - going to speaker negative. If so which are which.
The output socket on the box , should this only have the two connections from the output tranny on it or do I link the grounds.
Can I use a resistor across the output socket terminals to lessen the risk of tranny damage should it fire up without a speaker attached, if so what ohm and wattage.
Thanks for help here, I'm hoping to fire it up tomorrow.
Quote from: makaze808 on July 04, 2010, 04:28:06 PM
Does the inductor have polarity?
I don't think inductors are polarised, if in doubt copy my build(s).
Quote from: makaze808 on July 04, 2010, 04:28:06 PM
Regarding the output connections from the tranny is one + going to + on the speaker and the other - going to speaker negative. If so which are which.
Yes. And either. I make 2 +ve and 5 ground on my builds.
Quote from: makaze808 on July 04, 2010, 04:28:06 PM
The output socket on the box , should this only have the two connections from the output tranny on it or do I link the grounds.
I ground the input socket to the output socket, and to the circuit board.
Quote from: makaze808 on July 04, 2010, 04:28:06 PM
Can I use a resistor across the output socket terminals to lessen the risk of tranny damage should it fire up without a speaker attached, if so what ohm and wattage.
A resistor will affect the ratios if hardwired. You should use a switched socket if you want to do this, that way the resistor is only there if no jack is in the socket. I'd go for say 10 ohm 3 watt or 5 watt. There is probably a scientific way to work it out exactly, but that's not my job...... ;)
Quote from: prnet on May 16, 2010, 05:56:17 PM
Here my little DiamondG 1W...
http://www.thepiper.eu/?page_id=129
Finally...
still some little problem to solve but it's ooooook! (//)
Complimenti!!!
Thanks for the Help FC much appreciated. Just waiting on the power supply to arrive and a little bit of wiring in the mean time.
Help for debug needed >:(
I have no sound at all.
Center tap has 185v
Q1 c 1.2v
b 0.5v
e 0.0v
Q2 1 = 1.3v
2 = 12v
3 = 0v
Ypurs sincerely,
totally gutted.
Quote from: totally gutted on July 05, 2010, 10:15:02 AM
Help for debug needed >:(
I have no sound at all.
Center tap has 185v
Ok, the good news is that your SMPS is working, therefore the issue must be somewhere in the audio part of the circuit. And as the SMPS is working, no need to look at the voltages for Q1 and Q2. So, which layout are you using? One knob or two knob? Bias switch? All jumpers in place? Tubes the right way around (the gap between pins 1 and 8 should face the 555)? Tubes glowing? Rechecked your offboard wiring? Can you post voltages for the tubes?
I have a question.
I'm not really god at the tecnical stuff, but i wonder how much current is running through the trimpot? I have a mini Piher pot that is rated for 100V. Will that do?
:icon_lol: thanks for the sign posts, got it working, it was the tubes. maybe I missed info on socketing them but i struggled to get them all in tight, I'll prollly soldeer the next. I sort of trusted by build as I checked it more than ever while building it, so tubes became the prime suspect (after clearing all the waffle out of my head). Nice to actually find it first time.
I was blown away with it to be honest, really enjoyed playing it and far more effective as a house amp than 5 watters, which is what i've been using. TOmorrow I'll get chance to whack some effects at it. I took it to a bass players for a few hours and it was really really good, he couldn't stop playing it.
Thanks for bringing this nugget to the diy world.
So glad you got it going! Yeah, I'm still blown away every time I use mine (which is often). I added an on/off/on toggle (to my red one) for the bias mod and really enjoy the clean setting a lot.
Now can we see some photos please!
BTW makaze808, will you be at Wulfrun Hall on December 8th? ;)
I can't stop playing the thing.........great through my Marshall 4*12 LOL. I've just bought an 8inch speaker to hear what it's like through that, thinking of a combo build for my son.
I'll have to try the bias mod, cleaner is prolly good for me as I like to push with pedals. The Harmonic Perculator is having a great time.
Rick I'm finding the amp too bassy, my very bright rear pickup is kicking butt, but the neck is too woolly.
Do you think I might of used a wrong value somewhere which is producing the bass? Would an input or output cap help here?
Re Hawkwind
I'm in Manchester Rick so I'll be doing the Manchester Academy and Liverpool too. I'm a bit miffed with the current line up, last few times I have seen them it's been a bit false. I miss Davey a lot. Still toying with getting to the isle of white..........
Rick do you like the Levitation album, I think Huw is awsome on it and Ginger Bakers drums are so cool.
It's worth experimenting with the resistor value for the bias mod, I used 2.2k which is really good, but I might try 4.7k next.
If you went by the layout, your C2 and C7 will be 0.1uF. The stock Firefly uses 0.022uF, so maybe try those values to roll off some bass. I like bassy myself.
I just got a Marshall 1936 2x12 for mine. ;D
Yeah I adore Levitation, saw them 4 times on that tour. My favourite album is Quark, and the whole Calvert period. Calvert had an awesome stage presence on the Hawklords tour.
(http://www.punk77.co.uk/graphics/hawkwindcalvert.jpg)
Quote from: Beros on July 05, 2010, 07:55:40 PM
I have a question.
I'm not really god at the tecnical stuff, but i wonder how much current is running through the trimpot? I have a mini Piher pot that is rated for 100V. Will that do?
Anyone?
Quote from: Beros on July 09, 2010, 09:23:32 AM
Quote from: Beros on July 05, 2010, 07:55:40 PM
I have a question.
I'm not really god at the tecnical stuff, but i wonder how much current is running through the trimpot? I have a mini Piher pot that is rated for 100V. Will that do?
Anyone?
Oh Gawd, another forum to watch....
The 1K trimpot is in series with a 220k resistor (and a 470R resistor) from a nominally 200V supply, so the current (I = V/R) is roughly 200 /221,000 i.e. <1 ma.
Most of the 200V will be dropped by the 220k fixed resistor, so your 100V pot will be fine :icon_wink:
Someone above asked about output impedances... for the original circuit ~25k is reckoned to be optimal (by DougH, the designer), but the schematic was drawn when he was using a lower impedance, hence the confusion over the connection numbering. For the sub-mini version, it's anybody's guess. Particularly as the information on the 7327 is scant.
Incidentally, if you're in the UK, then the RS components 3.5W output transformer works well (better than the 125A IMHO) and is <£10. You need a slightly larger box to fit it on, though.
It's a cute project :)
(That's my hand in reply#168)
Use the 6111wa output tube and use 4-5k primary impedence when working out the tranny connections as stated earlier, it works a treat..
Highly recommended project. :icon_mrgreen:
This output transformer is mentioned several times
http://uk.rs-online.com/web/search/searchBrowseAction.html?method=retrieveTfg&binCount=1&Ne=4294957561&Ntt=oiutput+transformer&Ntk=I18NAll&Nr=AND(avl:uk,searchDiscon_uk:N)&Ntx=mode%2Bmatchallpartial&N=4294955308&Nty=1
Can this be dropped into the superfly replacing the 125a wihtout any mods to the circuit?
Quote from: makaze808 on July 12, 2010, 05:41:00 AM
This output transformer is mentioned several times
http://uk.rs-online.com/web/search/searchBrowseAction.html?method=retrieveTfg&binCount=1&Ne=4294957561&Ntt=oiutput+transformer&Ntk=I18NAll&Nr=AND(avl:uk,searchDiscon_uk:N)&Ntx=mode%2Bmatchallpartial&N=4294955308&Nty=1
Can this be dropped into the superfly replacing the 125a wihtout any mods to the circuit?
I would say yes. I used one for my original Firefly and for testing my sub-mini version, but reverted to the 125A for cosmetic reasons. In fact, IMHO it's a better sounding transformer than the 125A (YMMV!), but is physically a bit bigger. I've got one in my current 4-4-0 build, and it sounds grand.
You will need to choose the correct taps for the output impedance you want.
For info, I measured the turns ratios of the RS transformer as follows:
Primary connections 1 and 4 (2 is the centre tap)
Secondary
D-C 67.2:1
C-A 57.6:1
D-B 44.8:1
D-A 31.0:1
Primary connections 2 and 4 (3 is the centre tap)
Secondary
D-A 15.6:1
Primary tap 2 forms a centre tap between 1 and 4, and tap 3 forms a centre tap between 2 and 4. the 1-3 primary tap is no use for the firefly, because there is no corresponding centre tap, but the ratios are :
Primary connection 1 and 3 (N.B. No centre tap)
Secondary
D-C 50.0:1
D-B 33.3:1
D-A 23.1:1
To calculate the output impedance (in case you don't know) multiply your speaker impedance by (turns ratio) squared.
For example taps 1 & 4 on the primary with C & A on the secondary gives a turns ratio of 57.6:1 , so an output impedance for an 8 ohm speaker of:
8 x 57.6 x 57.6 = 26,542 ~ 26.5 k ohm
With this transformer in the original Firefly I used primary taps 1, 2 and 4, with D-C, C-A and D-B for 4, 8 and 16 ohm outputs respectively.
Going for lower impedances made it louder but harsher (again, YMMV!)
To clarify: You would connect B+ to terminal 2, and the anodes of the "power" valves to terminals 1 and 4 respectively, then choose the secondary terminals depending on your speaker impedance. You won't break anything by going for ~20 - 25k output impedance to start with (i.e 8 ohm speaker to terminals C and A).
Andy
Thanks for that reply, very help full.
Hi guys, do you think this amp will work fine with two 6021 submini tubes? :icon_wink:
Quote from: frankm on July 15, 2010, 12:23:31 PM
Hi guys, do you think this amp will work fine with two 6021 submini tubes? :icon_wink:
You should be able to do this. Just a couple of things to bear in mind regarding the preamp tube. 6112 has a gain of 70, 6021 has a gain of 30 (or 35, I forget), so you won't be pushing as much. This may be desirable and may actually make for a slightly cleaner, slighly quieter amp. You may want to change the two anode resistors (R12 and R13) to correctly bias for 6021, maybe socket them and experiment with 47k or 68k instead of 100k. May also be worth socketting the preamp 6021 so you can replace it with a 6112 at some point if you wish. I use SIL strips to sockets these subminis.
Just built one. Could really need some help.
Insead of it working, it makeas a beeping sound that changes when i turn the pot. Seems to be comming from the circuit itself or maybe the power supply...
Both tubes are glowing. Heat sink does get hot..
And, oh yeah, i put an 430 R resistor as R1, but that should'nt matter, should it?
I think i just fried something. I was measuring the voltage on the transformer center tap, and may have shorted something. Saw a spark and now the voltage reads 57 volts. Is it the IRF740 thats toasted?
With the ones I've built I can dial in higher voltages than 185v, so I'd be concerned about the voltage multiplier section. But you're getting HV so it's not all bad. The key part here would be the inductor, I've tried other inductors than the I usually use without any luck. Also, what's the spec of the 12v adapter you're using? Is the unit passing any sound? Got any photos of both sides of the board? Tubes in the right way round?
BTW, I *think* that 430R shouldn't matter - but it's not a 430k is it?
Quote from: frequencycentral on July 29, 2010, 05:56:49 PM
With the ones I've built I can dial in higher voltages than 185v, so I'd be concerned about the voltage multiplier section. But you're getting HV so it's not all bad. The key part here would be the inductor, I've tried other inductors than the I usually use without any luck. Also, what's the spec of the 12v adapter you're using? Is the unit passing any sound? Got any photos of both sides of the board? Tubes in the right way round?
BTW, I *think* that 430R shouldn't matter - but it's not a 430k is it?
No it's not a 430k.
No sound at all. It makes weird beeping noises comming from the circuit itself, not the speaker. Sounds different when i turn the pot or play a note. Still no sound from the speaker.
Uhm, i think i just fried or shorted something with my multimeter.. Now the center tap just rads about 50v...
The inductor is a 100uH radial one, similar looking to the one you use. Got it cheap from ebay.
The weird beebing noise when i turn the volume pot bothers me.. Thats not normal, is it?
Tubes are the right way around. Photos:
(http://i172.photobucket.com/albums/w28/pocksedd/krets1.jpg)
(http://i172.photobucket.com/albums/w28/pocksedd/krets2.jpg)
That PCB look different to my layout, particularly around the trimmer? If you shorted something it may blow the MOSFET or the inductor. Some of your caps are HUGE!
Quote from: frequencycentral on July 29, 2010, 06:38:18 PM
That PCB look different to my layout, particularly around the trimmer? If you shorted something it may blow the MOSFET or the inductor. Some of your caps are HUGE!
Yeah, I modified your layout since i got a smaller sized trim pot.
Had some orange drops laying around.
Changed inductor and the UF4004 (that's where the spark came from). Still 50-someting voltage on the transformer center tap.
Tomorrow I'll change the mosfet.
I've been going through the pcb over and over, and it's driving me nuts. Can't find whats wrong.
The power supply is 12V 500mA.
Beros that soldering don't look to good to be honest... :icon_cry:
Quote from: makaze808 on July 30, 2010, 01:08:39 PM
Beros that soldering don't look to good to be honest... :icon_cry:
I'm a guitar player. It's ok.
Quote from: Beros on July 30, 2010, 03:30:27 PM
Quote from: makaze808 on July 30, 2010, 01:08:39 PM
Beros that soldering don't look to good to be honest... :icon_cry:
I'm a guitar player. It's ok.
I think your soldering is fine. Sure it's not the neatest out there, but as long as there's no solder bridges or cold solder joints you should be fine. I would drag a pick through the negative spaces to clear out some of the flux and be sure there's no hard to see solder bridges. Also, look for any dull solder joints, as this can be a sign of cold joint that may need reflowed. The more you solder, the cleaner things will get. Good luck!
Sadly, even guitar players are not free of the bonds of physics. Even Jimi could not coax a tone out of an amp with solder bridges.
There were no solder bridges..
I just forgot to connect the transformer to ground. ;D
Well, I have sound. But I'm not free from trouble yet...
It's choppy and sounds weird.. Like a bad tremolo.
Transformer measures 70 volt.. Hmm...
Quote from: Beros on July 30, 2010, 05:19:57 PM
There were no solder bridges..
I just forgot to connect the transformer to ground. ;D
Well, I have sound. But I'm not free from trouble yet...
It's choppy and sounds weird.. Like a bad tremolo.
Transformer measures 70 volt.. Hmm...
Never mind... I think a new mosfet will do the trick.
Quote from: Beros on July 30, 2010, 09:01:02 PM
Quote from: Beros on July 30, 2010, 05:19:57 PM
There were no solder bridges..
I just forgot to connect the transformer to ground. ;D
Well, I have sound. But I'm not free from trouble yet...
It's choppy and sounds weird.. Like a bad tremolo.
Transformer measures 70 volt.. Hmm...
Never mind... I think a new mosfet will do the trick.
The mosfet must be doing something if you're getting 70V ???
I would suggest trying a different power adaptor before doing anything else - preferably a 1 amp *transformer* based one (i.e. the heavy type). Some switch mode power adaptors (i.e. the light type) don't react well to supplying the switching converter in this circuit. It will draw >600ma steady, but with much bigger spikes, and this sometimes seems to 'fight' with the regulation in the power adaptor.
HTH
Hey guys. I'm fairly new to the form and effect/amp building in general. Anyway I decided to be ambitious/stupid and attempt to build this sub-mini amp sometime in the near future and therefore I have been sourcing parts for this build. It seems that one of the hardest item for people to find is the 7327 tubes and I appear to have found someone who has a stash of them. I was surfing ebay and was that member chillo0 was selling some tubes he bought at a government auction, but in a lot with some 67 tubes total. I emailed him asking if he had some 7327s he could sell me to which he replied he had "lots." Long story short he sold me 3 tubes for $21 shipped, which seemed quite reasonable to me. When I got them they were well packaged and in good condition, new in the box. So if anyone out there needs a 7327 tube you could try looking him up.
Here's a link to the origional auction I found:
http://cgi.ebay.com/6T8A-6K6GT-CRC-5693-67-tubes-total-all-new-/5870527185?pt=Vintage_Electronics_R2&hash=item15de922d1
Another on the way:
(http://dl.dropbox.com/u/967492/Pete%27s%20Superfly.jpg)
Inspired by another thread I've collected some of the information in this thread on my wiki page about the Superfly (http://rumbust.net/tiki-index.php?page=Superfly) (feel free to add to the information there).
I'll post the lists I made of pre and power tubes here as I believe it to be useful (at least as reference for those browsing ebay and other sites).
Pre-amp tubes
In order of preference
6112 (gain about 70)
6021 (gain about 35)
6111 (gain about 20)
Power-amp tubes
In order of preference
7327 (unknown gain)
6021WA (gain about 35)
6021 (gain about 35)
6111 (gain about 20)
Hope this helps someone.
Hey guys, i'm getting my stuff together for this build... Having trouble finding a 7327 in the US... Was wondering if I could do two 6112's instead of a 6112 preamp and 6111w power amp... Whats a good place to get the output xfmr? A google search didn't turn up much in the way of Hammond 125a... :-\ I'm going to add a three band EQ to it, based on the P1 at ax84.com... Should make it a bit quieter but... If I use a 6112 (gain of 70) vs. a 6111 (gain of 20) in the power section, shouldn't it be louder?
6111 can be found on ebay.
trafos here should be good:
http://www.tubesandmore.com/scripts/foxweb.dll/catalog@d:/dfs/elevclients/cemirror/ELEVATOR.FXP
7327 are indeed hard to find, but it's not the end of the world. I've had a standard 6111 (ie not the W or WA derivative) running in a Superfly for about a year now, although the data sheet specifies a 150v maximum it's coping with 185v just fine. It is socketted (using SIL strip) just in case.
6112's spec makes it not really suitable for the self spilt output stage. Just as the Firefly uses a high mu 12AX7 for the preamp and a low mu 12AU7 for the output stage, so the Superfly does the same. But you could try it with a 6112 (socket it maybe), I haven't myself, it might work/sound fine for all I know.
Hammond 125A should be really easy to source in the US. I'm in the UK and always use Bluebell (http://www.bluebellaudio.com/)
Any chance I could get one of you guys to try a 6112 in the power section before I buy tubes... ?
hey rick,
Great work on the superfly:) love the look of your amps!
Im based in the UK and was wondering exactly what you use for the nixie supply.
I want to get 310v to power a preamp pedal and was wondering exactly what parts from where you used to get the 310v?
cheers
c
Quote from: MetalUpYerEye on February 13, 2011, 07:26:20 PM
Any chance I could get one of you guys to try a 6112 in the power section before I buy tubes... ?
As I'm not recommending it I'm not trying it. ;)
Quote from: craigmillard on February 14, 2011, 04:58:26 AM
hey rick,
Great work on the superfly:) love the look of your amps!
Im based in the UK and was wondering exactly what you use for the nixie supply.
I want to get 310v to power a preamp pedal and was wondering exactly what parts from where you used to get the 310v?
cheers
c
The SMPS I use is in the first post. The critical parts would appear to be:
- the inductor, Rapid part # 88 1630 MIN RADIAL INDUCTOR 100UH RC, but I'm sure others will work.
- the ultrafast diode UF4004, just don't even bother trying non ultrafast type diodes
- MOSFET - I've used both IRF740 and IRF840.
- The voltage rating of C4 in the SPMS schematic 350v or 500v or whatever. It's value is less important, the higher the better really. Now I'm using 4.7uF / 350v, It's a trade-off between spec and physical size.
You can also screw around with the ratios of R4 and R5, which dictate at what voltage the BC547 switches off the NE555. That's your govnor right there and really dictates the maximum voltage. Just be careful - it's possible to put out enough voltage to melt/combust the MOSFET and reservoir cap!
thanks rick that is a great help!!
Im about to put a big order in at farnell and dont want to have to pay the extra at rapid just to ship some inductors, do you think these will work?
They look similar spec to the ones you use?
I take it in an inductor we are looking for low dc resistance and high current, what about the Resonant Frequency?
http://uk.farnell.com/panasonic/elc10d101e/choke-100uh-0-110ohm-1-7a/dp/1308459
http://uk.farnell.com/panasonic/elc16b101l/choke-100uh-2-6a-0r072/dp/1749179
Cheers
C ;D
I've been sourcing parts for this and dreaming about building it, while doing so I reworked the PCB to my own style :) It's Ricks layout (http://www.diystompboxes.com/smfforum/index.php?topic=78302.msg704930#msg704930) but with two jumpers removed (and Q2 flipped to do so). It's also one row and one column smaller :)
Refer to Ricks layout for connections and mods.
N.B: As of this writing this is unverified.
(http://i832.photobucket.com/albums/zz249/Perrow_MLP/Stomp/Superfly_pcb_and_component_layout.png)
So I'm stocking up parts to build me one of these and as I'm on a tight budget I'm hoping to use (for a start at least) this salvaged output transformer. The problem is that I'm not really sure what I've got, so please help me, can this be used? I know there's ideally impedance matching to be considered, but at least the secondary side should be safe considering it's attached to the speaker ;D
I know there should be three wires going from the output tube to the transformer and that there are four here, I just don't know enough about this subject to know if it's at all possible to use this or if I'll have to fork out for a 125A.
(http://i832.photobucket.com/albums/zz249/Perrow_MLP/Tube%20radio/DSCN0679.jpg)
More images here (http://s832.photobucket.com/albums/zz249/Perrow_MLP/Tube%20radio/)
Grateful for any light you can shed on this.
Quote from: Perrow on February 23, 2011, 06:15:07 PM
So I'm stocking up parts to build me one of these and as I'm on a tight budget I'm hoping to use (for a start at least) this salvaged output transformer. The problem is that I'm not really sure what I've got, so please help me, can this be used? I know there's ideally impedance matching to be considered, but at least the secondary side should be safe considering it's attached to the speaker ;D
I know there should be three wires going from the output tube to the transformer and that there are four here, I just don't know enough about this subject to know if it's at all possible to use this or if I'll have to fork out for a 125A.
(http://i832.photobucket.com/albums/zz249/Perrow_MLP/Tube%20radio/DSCN0679.jpg)
More images here (http://s832.photobucket.com/albums/zz249/Perrow_MLP/Tube%20radio/)
Grateful for any light you can shed on this.
that could be one of those ancient speakers that used the filtering choke from the powersupply as an electromagnet in the speaker, instead of alnico or cheramic...I say could be, since I dont know. .it might not be an output transformer, so dont just assume it to be...I guess someone like PRR would know thou..
Inductor question:
They were cheap - so if one is wrong - I'm not out much.....
I got these two inductors:
(http://pws.cablespeed.com/danielzink/musical/chokes.jpg)
One is labeled as a 100uH RF Inductor the other as an RF Choke Power inductor.
Are they functionally the same re: this circuit ?
Thanks !
Dan
Did anyone ever make this in eagle? I've got this penned for a summer project, I liked the look of the vox lil' night train but this is just amazing!
If not, I might eagle it myself sometime. It's an extremely elegant design, what are people's solutions to the standoffs?
@ Dan: Well they look right physically, but the ones I use are labelled '104'. I think inductor labelling is the same as cap labelling, so (to me at least, I'm happy to be corrected), the '101' markings don't look right.
@ Hides: I'm using 15mm nylon standoffs from Banzai.
(http://dl.dropbox.com/u/967492/Superfly%204/SF41.jpg)
(http://dl.dropbox.com/u/967492/Superfly%204/SF42.jpg)
(http://dl.dropbox.com/u/967492/Superfly%204/Sf43.jpg)
(http://dl.dropbox.com/u/967492/Superfly%204/SF44.jpg)
(http://dl.dropbox.com/u/967492/Superfly%204/SF45.jpg)
Nice as allways.
I'd love to see a component side shot of your board.
Is there anything like to large for the high voltage electrolytes? I found two 400V 22uF while looking at the switching PS in an "old" network switch recently, that aren't that big so they might actually fit (a bit high maybe, but that's all). I think you said earlier that "the bigger the better" and I know that that's mostly the case when it comes to electrolytes.
Still hoping someone would have an educated guess about the OT I posted above.
hi all, this is my last submini amp version.
here is the BumbleBee:
-One triode preamp
-cathode follower
-complete tone stack
-One triode in class A mode
and sound amazing, and more powerfull than the jj´s submini, that is based in.
(http://i783.photobucket.com/albums/yy114/DrMalignoTech/Submini-Amplification/100_1946.jpg)
(http://i783.photobucket.com/albums/yy114/DrMalignoTech/Submini-Amplification/100_1945.jpg)
(http://i783.photobucket.com/albums/yy114/DrMalignoTech/Submini-Amplification/100_1939.jpg)
thanks rick for inspire all to do little thinks
Could someone please point me in the right direction regarding the transformer.
Which one of these is the correct one to use.
http://www.x-on.com.au/results-deep-new.asp?sq=125A+transformer&tp=
And where is the cheapest source for this.
Is there a cheaper option?
Thanks in advance.
Quote from: Poste on March 07, 2011, 08:20:59 PM
Which one of these is the correct one to use.
http://www.x-on.com.au/results-deep-new.asp?sq=125A+transformer&tp=
None of the above.
You're looking for a Hammond 125A (not anything else, even 125ASE) - e.g.
http://gb.mouser.com/ProductDetail/Hammond-Manufacturing/125A/?qs=sGAEpiMZZMv0IfuNuy2LUXxqWx0SplZ5kwH0lm%252bN3RM%3d
if you're in the UK:
Bluebell Audio (http://www.bluebellaudio.com/) or Das Musikding (http://www.musikding.de/product_info.php/info/p809_Hammond-125A-output-transformer.html) - if you can cope with a physically larger transformer, this one (http://uk.rs-online.com/web/2106475.html) is better (IMHO) and cheaper.
If you're in the US, I'll leave someone else to advise you. (But I've heard they grow on trees there ;) )
Andy
I would like to hook this up to a cab with a switch to choose between a tiny giant and the superfly, can I run 15V through this circuit instead of 12V.
And is the tone stack a good feature to include?
Thanks in advance
The tubes' heater will burn out at 15 volts. But you could use a 7812 to feed the circuit from a 15 volt supply. Tonestack? Personal preference, you lose some volume.....
Ok so it sounds like it is possible then, I actually stuffed up the power supply I have is 16V.
Now here are a few more questions
1) How could I use the 7812 to feed the curcuit?
2) Should I switch the power in between circuits, my thoughts are that the tubes "wear" out with power going through them so switching power would prolong the life of the tubes to the time when they will be in use instead of being in standby. But tubes like to be in standby, or need to be heated up correct? What would be the best approach here?
3) If I have the 16V power supply feeding both curcuits will there be enough power without overloading the supply?
Sorry if these sound like silly questions, I only have a basic knowledge of things electric.
Quote from: Poste on March 11, 2011, 09:31:58 PM
Ok so it sounds like it is possible then, I actually stuffed up the power supply I have is 16V.
Now here are a few more questions
1) How could I use the 7812 to feed the curcuit?
2) Should I switch the power in between circuits, my thoughts are that the tubes "wear" out with power going through them so switching power would prolong the life of the tubes to the time when they will be in use instead of being in standby. But tubes like to be in standby, or need to be heated up correct? What would be the best approach here?
3) If I have the 16V power supply feeding both curcuits will there be enough power without overloading the supply?
Sorry if these sound like silly questions, I only have a basic knowledge of things electric.
1) you need to research the 7812 and see how it is utilized in a circuit to see how you could best implement it.
2) can you maintain power to both circuits ? you need to sort that out as well...
3) 16v is 16v...... question is.....do you have the amperage ? you haven't actually said yet - exactly what kind of power supply you'd like to power both of these circuits with...and how will you "split" the power ? You can supply 12 volts to two car engines....but will you have the amps to start either one of them ?
Quote from: Poste on March 11, 2011, 09:31:58 PM
Sorry if these sound like silly questions, I only have a basic knowledge of things electric.
In light of this last statement...
Let me give you some advice that
Rick himself gave
me recently........
Quote from: frequencycentral on February 28, 2011, 04:37:14 PM
Superfly: SMPS power supply, 180 + volts, difficult to get exactly right, the right inductor matters. Trimmer needs adjusting just right. Be careful....the power supply can give you a real jolt. Just be warned - the Superfly SMPS is not for beginners. With the Superfly you gotta know what you're doing and take care of yourself while you do it.
Don't get me wrong - I am
not trying to talk you out of this build - I just think you need to figure out
every aspect of it before you go charging in....this is an
amplifier...not a 9V tubescreamer...
I did 2 months worth of research before I ever put an iron to a board on my Firefly build..
nobody wants you to smoke your power supply...or yourself...
Dan
I also think that, since the Tiny Giant's power demands are special too, you're pairing up 2 projects with special power needs and trying to run them off the same supply. I think it could be a recipe for one or many disasters.
I would build them separately.
Since you say you only started building electronics a couple of months ago, don't try to push yourself too quickly. Both of these projects require some serious thought and attention by themselves, and you can potentially hurt yourself and/or smoke/melt parts if something goes wrong. Attempting to do some special trickery with already tricky projects when still relatively new to the craft is probably not a good idea.
Would using an IRF840 & UF4007 in this be possible or is it just asking for trouble to mess around with the delicate nature of the charge pump?
The IRF840 has specs of 500V Vdss, 0.85 Rds & 8A Id... Fairly close to the 740 and I think the UF4007 just has a higher voltage rating than the 4004.
Edit:Bugger, just noticed the answer to the IRF840 question on the page before... and a Semi-Answer to the UF4007 question... i'll probably just risk that.
Close enough for jazz I should say. ;)
BTW, the next one I build will have a panel mount pot in place of the trimmer to act as a kinda poor man's variac. I just need to calculate the voltage divider ratios so the 'brake' pot can only be at 185v at it's maximum.
So... I took a stab at this making a PCB layout to fit a 1590BB with Onboard Pots & Tube Sockets using the MAX1771 Charge Pump & Standard Sized Tubes with an Added Big Muff Tone Stack (With Shelve Filter) and this is where my first attempt got me...
(http://i898.photobucket.com/albums/ac182/Scruffie_Crow/MiniFireFly-1.gif?t=1301387467)
(96.52mm x 71.12mm)
I'm not overly happy with how it's come out so I wondered if you had any tips for how you go about laying them out Rick? I keep trying to lay it out like a Stompbox which just doesn't work and leads me into corners...
Any suggestions would be appreciated.
Quote from: Scruffie on March 29, 2011, 04:39:23 AM
(http://i898.photobucket.com/albums/ac182/Scruffie_Crow/1590BBSuperflyPCB.gif?t=1301387424)
Any suggestions would be appreciated.
There's an area just south west of the AU tube that makes five lines take a detour.
There's a (ground) line just north west of those lines that takes a voluntary detour, looks odd.
The 12V+ line could go from the MAX1077 pin 2 direct to a point just above C8 instead of running all the way down to C10.
You could possibly move the FET to the side and nail it to the enclosure.
Not the most solid comments, but my 2c anyway :)
Quote from: Perrow on March 29, 2011, 07:06:02 AM
There's an area just south west of the AU tube that makes five lines take a detour.
There's a (ground) line just north west of those lines that takes a voluntary detour, looks odd.
The 12V+ line could go from the MAX1077 pin 2 direct to a point just above C8 instead of running all the way down to C10.
You could possibly move the FET to the side and nail it to the enclosure.
Not the most solid comments, but my 2c anyway :)
I've been going over it all morning and I can't beleive I didn't notice those Detours were unneccesary :icon_mrgreen:
Looks much better now, i've also adjusted the FET to be in line with the PCB design advice given in the original Nixie Document and noticed that this version doesn't need a Heat Sink so I could move it much closer and have shorter traces.
Version 2:
(http://i898.photobucket.com/albums/ac182/Scruffie_Crow/1590BBSuperflyPCB-3.gif?t=1301406444)
(http://i898.photobucket.com/albums/ac182/Scruffie_Crow/1590BBSuperflySS-2.gif?t=1301406442)
There are two R12s to Parallel them due to the obscure value of 0R050 (0R1 is a little more common) and two pads to the side of the inductor to accept other sizes.
Pete, I find that type of layout really hard to visualise compared to DIYLC, but I think it's really neat how you've got everything onboard. The whole concept is very attractive to me actually, I'll have to build one! BTW, I've used a single 0R1 resistor in MAX1771 based builds with success. I also altered the trimmer and associate voltage divider values slightly.
This does look great. I've been wanting to try one of these amps again, now that the wound of my previous attempt is healed and forgotten. Would this 12ax7 version use the same or similar transformer?
Quote from: Taylor on March 29, 2011, 03:47:48 PM
This does look great. I've been wanting to try one of these amps again, now that the wound of my previous attempt is healed and forgotten. Would this 12ax7 version use the same or similar transformer?
The only difference here would be the Tubes are Full Sized & The Nixie Supply is different, the rest is the same and the 125A Would still be the Tranformer to use, it's kinda the best of both worlds in my book (Except for the slightly larger enclosure).
I did consider making a version with the original 555 Nixie aswell, but I think the MAX1771 is more efficient so will work better with Full Tubes if I understand it correctly... which I don't.
Quote from: frequencycentral on March 29, 2011, 03:41:03 PM
Pete, I find that type of layout really hard to visualise compared to DIYLC, but I think it's really neat how you've got everything onboard. The whole concept is very attractive to me actually, I'll have to build one! BTW, I've used a single 0R1 resistor in MAX1771 based builds with success. I also altered the trimmer and associate voltage divider values slightly.
Ahh, I did wonder about visibility, if you try and print the image of the layout the same as DIYLC though it all comes out in all black and looks even more confusing... or in colour in XML documents but I have sod all clue what an XML document is or how to use it.
It does connect up properly though, i'll tweak it and check it some more and add a final version up tommorow, i'm certainly going to build one up in the future once i've got hold of a PCB and Transformer, let me know if you beat me to it though! Be great to verify this one.
Cause I think we can all agree... wiring Pots by hand is a right pain in the Arse.
I'll leave the extra pads for the parallel resistor... just incase someone can only find a 0R2, doesn't really make a whole lot of difference to the layout.
Here we go, altered it now, this should be the Final Version, Checked it over and it all looks good.
(http://i898.photobucket.com/albums/ac182/Scruffie_Crow/1590BBSuperflyPCB.gif?t=1301443121)
(http://i898.photobucket.com/albums/ac182/Scruffie_Crow/1590BBSuperflySS.gif?t=1301443268)
Well I thought it looked good but I realise i've made what can only be described as a Monumental %^&* up... I neglected to notice that on the 12AX7 Datasheet the Diagram Said... 'Bottom View... so they are in fact... backwards :icon_redface:
What's the view on mounting them on the back of the board? Would there be enough depth in a 1590BB to get away with it with the Board Mounted pots?
While we're here anyway as I did catch one more mistake on that past layout (The Heaters don't go back to ground) I am right in saying that Pin 9 shouldn't be in use here right?
I'll keep trying to do a layout with the Tubes orientated correctly but it's not quite as easy to get away without Jumpers...
While you're at it, the tubes are mounted quite close to each other, are they wider than the sockets? I haven't had first hand experience with 12A_7 tubes so I don't really know, so if you've taken that into consideration don't bother about this comment, just thought they looked rather close to each other.
And you might think about trimming your pcb image next time. A little too much white space in the ones you've posted here ;)
Quote from: Perrow on March 30, 2011, 08:20:40 AM
While you're at it, the tubes are mounted quite close to each other, are they wider than the sockets? I haven't had first hand experience with 12A_7 tubes so I don't really know, so if you've taken that into consideration don't bother about this comment, just thought they looked rather close to each other.
Yeah the new one will have them spaced a bit farther apart, I haven't got any Tubes, Sockets or Enclosures to hand so it's all a bit of a judgement call as to what constitutes too close... they'd fit but I don't know how tightly.
Quote from: Perrow on March 30, 2011, 08:21:54 AM
And you might think about trimming your pcb image next time. A little too much white space in the ones you've posted here ;)
Haha, yeah I will do, I don't like to mess about with the images for PCBs when they come out of Express PCB so I just stick them up as is, point taken though ;)
I'm a little confused about the revision history here, but assuming I'm ok with mounting the tubes on the back of the board, is that last layout good to go Scruffie? I'd love to build one of these up.
Quote from: Taylor on March 31, 2011, 12:41:19 AM
I'm a little confused about the revision history here, but assuming I'm ok with mounting the tubes on the back of the board, is that last layout good to go Scruffie? I'd love to build one of these up.
Not quite, I misunderstood how to wire the heaters on that, i'll try and get both updated versions on here today.
Hey Scruffie, may we have the Expressfile? I want to have the lines thicker...
Thanks for the pcb
Quote from: Maik on March 31, 2011, 02:55:51 AM
Hey Scruffie, may we have the Expressfile? I want to have the lines thicker...
Thanks for the pcb
If you PM me your e-mail address yeah.
Quote from: Taylor on March 31, 2011, 12:41:19 AM
I'm a little confused about the revision history here, but assuming I'm ok with mounting the tubes on the back of the board, is that last layout good to go Scruffie? I'd love to build one of these up.
Here ya go Taylor, this'd be the one to etch now, Fixed the Tube Heaters (As far as my knowledge goes) corrected two missing parts, spaced the Tubes further apart and shrunk the board a tiny amount... this should, fingers crossed, all be good now.
If you're etching one for yourself do you think I could buy one off you?
And I don't think I will be doing a PCB with the tubes corrected, it just doesn't come out as nicely without starting everything again and i'm pretty happy with this layout... plus I prefer the circuit to face me when I open an enclosure anyway. If it struggles to fit nicely in a 1590BB, the Smallbear 125BB would probably be perfect.
(http://i898.photobucket.com/albums/ac182/Scruffie_Crow/SuperflyPCB.gif?t=1301569599)
(http://i898.photobucket.com/albums/ac182/Scruffie_Crow/SuperflySS.gif?t=1301569601)
96.52 x 69.85mm
For @#$%s Sake, The Heaters are Still wrong aren't they, can someone explain how I wire them?
Am I right In saying 12V runs Directly into Pin 4 on Both Tubes and Both Pin 5s go to ground? Do the Pin 5s have to connect or just go straight to ground? Do I connect Pin 4 & 5 Together?
Pin 4 of both tubes to ground. Pin 5 of both tubes to +12v. Pin 9 no connection. I *think* you can also do it the opposite way, ie pin(s) 4 to +12v, pin(s) 5 to ground. You definately do not connect pins 4 and 5 together. You may be getting confused due to the way the submini heaters in Superfly are wired in series (because they are 6.3v heaters), but this is not necessary with the 12##7 version. Would be worth you checking out DougH's original Firefly schematic.
Quote from: frequencycentral on March 31, 2011, 01:43:16 PM
Pin 4 of both tubes to ground. Pin 5 of both tubes to +12v. Pin 9 no connection. I *think* you can also do it the opposite way, ie pin(s) 4 to +12v, pin(s) 5 to ground. You definately do not connect pins 4 and 5 together. You may be getting confused due to the way the submini heaters in Superfly are wired in series (because they are 6.3v heaters), but this is not necessary with the 12##7 version. Would be worth you checking out DougH's original Firefly schematic.
Yeah I wired them like the Superfly reading that the heaters needed 6.3V thinking that seemed right as it was half of 12.6V, then looked at the 12AX7 again to see it said 12.6V and... well you get the idea.
I thought Pin 4 to +12V was the norm... All the information I keep finding starts off being for series and then the topic ends up being for parallel... i'll have to keep checking, having voltage to Pin 4 would be nice layout wise.
I did check Dougs original schematic and it has the Heaters wired in Parallel which wouldn't work here.
Edit: Question answered http://www.diystompboxes.com/smfforum/index.php?topic=86051.0 Both the same :)
^^^
Yeah, makes sense, as some amps use AC for the heaters. They like it both ways.
EDIT: There may be a benefit to using the 12##7 heaters at 6.3v in series, the total ma consumption would half in comparison with series. Both tubes combined would only draw 150ma in series versus 300ma in parallel. Might be worthwhile considering the ma hungry nature of SMPS's.
Quote from: frequencycentral on March 31, 2011, 02:49:51 PM
^^^
Yeah, makes sense, as some amps use AC for the heaters. They like it both ways.
EDIT: There may be a benefit to using the 12##7 heaters at 6.3v in series, the total ma consumption would half in comparison with series. Both tubes combined would only draw 150ma in series versus 300ma in parallel. Might be worthwhile considering the ma hungry nature of SMPS's.
Huh... I thought this was series wiring... I thought I put 12.6V into Pin 4 of Both Tubes and Pin 5 to Ground on Both Tubes and that was Series and parallel was when Pin 9 Got involved, i'm so very, very confused :icon_cry: :icon_lol: Will that not be 150ma Then?
If not... what could I do... fitting a Regulator on at this stage would be a right bitch, fitting anything on at this stage would be really... a 6.2V Zener?
Is there any places suggested for learning this better, I keep searching but nothing really explains it to me in simple terms.
Here's two very slightly different PCB Versions to choose between though with it wired in series or parallel or whatever this is... One has 12V going to Pin 5 of Both Tubes which means that the Pin 4 ground is running between 12V & The Input Trace but it's a bit tight or there's one with Pin 4 Getting 12V on both Tubes and Pin 5 off to Seperate Grounds.
(http://i898.photobucket.com/albums/ac182/Scruffie_Crow/SuperflyPCB-2.gif?t=1301600020)
(http://i898.photobucket.com/albums/ac182/Scruffie_Crow/SuperflyPCB2.gif?t=1301600024)
Quote from: Scruffie on March 31, 2011, 07:11:42 AM
If you're etching one for yourself do you think I could buy one off you?
Once the layout's all sorted, if I'm making any PCBs I would be happy to send you one gratis. :) Thanks for putting that together (and thanks of course to Doug and Rick for the cool circuits).
QuoteHuh... I thought this was series wiring... I thought I put 12.6V into Pin 4 of Both Tubes and Pin 5 to Ground on Both Tubes and that was Series and parallel was when Pin 9 Got involved, i'm so very, very confused icon_cry icon_lol Will that not be 150ma Then?
You are correct. Pin 4 and 5 are the ends of the heaters, pin 9 is the center tap. So, with pins 4 and 5 connected to either end of the heater supply, it's 12.6v, 150ma (series heaters) - heaters are basically resistors, so there is no polarity. With pins 4 and 5 tied together and connected to one end of the heater, and pin 9 connected to the other end of the heater supply, it's 6.3v 300ma (parallel).
If the heater circuit is grounded properly, and the layout is good (*), there is no reason to rectify the heater supply for DC. There are many ways of dealing with ground referencing AC heaters. Usually either the center tap of the heater winding is grounded, or two 100r resistors are used to create and artificial center tap, or a pot is used instead of the 100R resistors with the wiper grounded so one can adjust for minimum hum. All of these schemes balance the positive and negative sides of the AC power for the heaters more or less equally with respect to ground. Unlike typical stomp box "grounds", this ground connection does not carry current, it simply provides a voltage reference for the AC heater supply. I would not recommend grounding one side of the heater supply, primary because if the "real" amps don't do it often/ever, then there's probably a reason why.
For the sake of heater induced hum, I have read there is some benefit of using 12.6v and 150ma because the lower current emits a lower electromagnetic field and is less likely to couple to the cathode of the tube (the more current in a conductor, the more EMF it emits). I have never bothered to verify this, I'm lazy and elevate my heater supply by about 45v DC to reduce coupling and lower the cathode to heater voltage in cathode follower circuits which is often near or over max spec with many circuits.
Since you are designing a circuit board, I'd advise prototyping it to make sure you don't have strange coupling going on between the different parts of the circuits. Usually DC heaters are used because they don't couple very well to other parts of the circuit on a PC board, it has little to do with the heaters themselves and more to do with the board layout. This may or may not be a problem for you; you'll have to test it to find out.
Quote from: defaced on March 31, 2011, 08:28:42 PM
QuoteHuh... I thought this was series wiring... I thought I put 12.6V into Pin 4 of Both Tubes and Pin 5 to Ground on Both Tubes and that was Series and parallel was when Pin 9 Got involved, i'm so very, very confused icon_cry icon_lol Will that not be 150ma Then?
You are correct. Pin 4 and 5 are the ends of the heaters, pin 9 is the center tap. So, with pins 4 and 5 connected to either end of the heater supply, it's 12.6v, 150ma (series heaters) - heaters are basically resistors, so there is no polarity. With pins 4 and 5 tied together and connected to one end of the heater, and pin 9 connected to the other end of the heater supply, it's 6.3v 300ma (parallel).
If the heater circuit is grounded properly, and the layout is good (*), there is no reason to rectify the heater supply for DC. There are many ways of dealing with ground referencing AC heaters. Usually either the center tap of the heater winding is grounded, or two 100r resistors are used to create and artificial center tap, or a pot is used instead of the 100R resistors with the wiper grounded so one can adjust for minimum hum. All of these schemes balance the positive and negative sides of the AC power for the heaters more or less equally with respect to ground. Unlike typical stomp box "grounds", this ground connection does not carry current, it simply provides a voltage reference for the AC heater supply. I would not recommend grounding one side of the heater supply, primary because if the "real" amps don't do it often/ever, then there's probably a reason why.
For the sake of heater induced hum, I have read there is some benefit of using 12.6v and 150ma because the lower current emits a lower electromagnetic field and is less likely to couple to the cathode of the tube (the more current in a conductor, the more EMF it emits). I have never bothered to verify this, I'm lazy and elevate my heater supply by about 45v DC to reduce coupling and lower the cathode to heater voltage, which is often near or over max spec with many circuits.
Since you are designing a circuit board, I'd advise prototyping it to make sure you don't have strange coupling going on between the different parts of the circuits. Usually DC heaters are used because they don't couple very well to other parts of the circuit on a PC board, it has little to do with the heaters themselves and more to do with the board layout. This may or may not be a problem for you; you'll have to test it to find out.
I lost track after You are Correct... Thanks for taking the time for the thorough explanation though, hopefully during the course of this build i'll begin to understand tubes a little better, it's entirely new territory to me.
But, from my reading and from that, either one of the above two PCBs should now work, atleast in theory... any problems that come of the layout we'll have to find out with prototyping as you say.
I think... from what I gather having the heater wires run parallel is a good thing (I don't know why but it seemed to be what everyone was doing on there builds on the AX84 forum) so the 1st PCB of the Two should be best with the Tight Tracks (I'll remove the others now so there's no confusion anyway).
Quote from: Taylor on March 31, 2011, 07:49:17 PM
Quote from: Scruffie on March 31, 2011, 07:11:42 AM
If you're etching one for yourself do you think I could buy one off you?
Once the layout's all sorted, if I'm making any PCBs I would be happy to send you one gratis. :) Thanks for putting that together (and thanks of course to Doug and Rick for the cool circuits).
Seems to me to be sorted, well as far as we can tell untill we actually build it! So that'd be greatly appreciated :)
And yeah thanks Doug and Rick... I may not understand these glass things but I know they sound good :icon_mrgreen:
QuoteI lost track after You are Correct... Thanks for taking the time for the thorough explanation though, hopefully during the course of this build I'll begin to understand tubes a little better, it's entirely new territory to me.
No problem, you guys with your little chips and 9v batteries are new territory to me.
Some suggestions for more knowledge that's easy to attain/understand:
- Wander over the the Music Electronics Forum and start reading. That's where I learned most of my tube knowledge over the past several years. Some of the guys are old and grumpy, but they know their stuff. They grew up with it.
- Look at the datasheets of the tubes you're using and try to understand them, at least the pinout and what each piece of the tube does. The heater circuit, if you just think about it as two resistors, makes more sense once you see how the heaters are wired inside of the tube.
- Schematics of old/popular amps to "see" what's doing on in the heater circuits of these amps.
- Valve Wizard and Aiken Amps are also two other very good tube resources.
- And last but not least, there's a tech help page here at DIYSB (on the main page) that covers tube anatomy and what each component does. It was a HUGE help when I didn't know what a "plate resistor" was.
Having heaters run parallel is actually a not the way you're supposed to do it, but it often doesn't matter. Twisted pairs of wire are the "proper" way to do heaters because a twister pair shields really well. Without knowing it, you're in lead dress land. http://www.geofex.com/article_folders/lead_dress/lead_dress_in_tube_amps.htm (http://www.geofex.com/article_folders/lead_dress/lead_dress_in_tube_amps.htm)
This is twisted pair wired heaters (not my work, but a great example):
(http://i52.photobucket.com/albums/g39/joeyvoltage/DSC07630.jpg)
Hey Taylor, do you make some more?
I like your pcb´s and want to order one or two... ;D
Hi Maik,
I had no plans to sell these boards - I was just going to make one for myself, maybe make one for my father, and one for Scruffie as thanks for doing the layout and adapting it to full-size tubes. I'm not set up to do lots of etched boards, and before I could think of doing a fabricated one, I'd have to run it by everybody involved in the project first. I'm not even sure they'd all be ok with it, and my personal ethics or whatever precludes me from going forward in that case.
So, for the time being I can't, I'm afraid, but down the road, who knows?
Quote from: Scruffie on March 29, 2011, 04:39:23 AM
So... I took a stab at this making a PCB layout to fit a 1590BB with Onboard Pots & Tube Sockets using the MAX1771 Charge Pump & Standard Sized Tubes with an Added Big Muff Tone Stack (With Shelve Filter) and this is where my first attempt got me...
(http://i898.photobucket.com/albums/ac182/Scruffie_Crow/MiniFireFly-1.gif?t=1301387467)
(96.52mm x 71.12mm)
I'm not overly happy with how it's come out so I wondered if you had any tips for how you go about laying them out Rick? I keep trying to lay it out like a Stompbox which just doesn't work and leads me into corners...
Any suggestions would be appreciated.
Hi Scruffie and thanks for posting the "big valve" version on Rick's (Doug H) super cool amp.
I just happen to have one EL90 pentode that I like to tri to use as power stage. So I'm in the process of making a layout for this purpose. Some questions though.
- Have you tried the tone stack, it does not appear to be a Big muff clone to me. The ones I have seen has no 4n7 and 3,9 nF and 39K in sted of 47K, is it??
- On the original from rick there is a 47 uF Cap from pin 1 to GND on the 12ax7 why did is it why did you omit that one?
The EL90 has only a 6,3V heater so I have to chip in a LM317 to regulate the voltage.
Thanks
Quote from: solderman on April 03, 2011, 03:13:49 PM
Hi Scruffie and thanks for posting the "big valve" version on Rick's (Doug H) super cool amp.
I just happen to have one EL90 pentode that I like to tri to use as power stage. So I'm in the process of making a layout for this purpose. Some questions though.
- Have you tried the tone stack, it does not appear to be a Big muff clone to me. The ones I have seen has no 4n7 and 3,9 nF and 39K in sted of 47K, is it??
- On the original from rick there is a 47 uF Cap from pin 1 to GND on the 12ax7 why did is it why did you omit that one?
The EL90 has only a 6,3V heater so I have to chip in a LM317 to regulate the voltage.
Thanks
I have not tried any of this at all, The Tone stack has the values of the first schematic for the Big Muff Tone Stack Google Came up with, personally i'll be using 2 x 47k & 2 x 10n.
The 4n7 is there to act as a Shelving Filter type of set up so when you roll the tone stack back to the bass side, you don't loose all the highs, you don't have to have it but I prefer it that way.
The Schematic I worked from was Ricks 'Superfly Special' which is a couple of pages back and that did not include the 47uF Cap... You'll have to ask Rick that one, it's just for the Reference Voltage though.
Tube Heating isn't my strong point as we've found during these last few pages :D but a LM317 sounds reasonable.
Good Luck with your Build!
OK thanks
I'll try this and send in an update as soon as I'm done
I'm going to start getting my stuff together for this build now that i've done a bit of reading on it...
I was wondering if this output xfmr will work... Or do I have to shell out $30+ for a Hammond 125a?
http://www.tubesandmore.com/scripts/foxweb.dll/moreinfo@d:/dfs/elevclients/cemirror/ELEVATOR.FXP?item=P-T125A
Also 1/4 watt resistors are fine right? Are there any higher voltage electrolytic caps that i'll need for the power supply?
bump. Just trying to get a bit of info so I can build this baby... ;)
That transformer is fine.
All resistors are 1/4 watt.
The only high voltage electro you need is the reservoir cap(s) for the SMPS. I've used 2.2uF/450v as well as 4.7uF/350v. Any bigger value and you're looking at a physically big cap which may preclude a 'submini' build. I prefer 4.7uF/350v - just make sure you don't pop the cap by letting the SMPS voltage over run.
I'll have to see what my local parts place has for 350v/450v caps... I might just go 450v since i'll probably build this into an 8" combo so there should be plenty of space... I'm also going to add a three-band EQ section based off the P1 from AX84.com so that should be pretty nice... It'll be in place of the 'tone' control in the 'Superfly Special' schematic.
You have been tuning your trim pot to feed the 6111WA with 185 volts right?
Sorry I just realized... The xfmr that that link takes you to is a Hammond 125a... I was looking at the Fender P-T1750a at www.tubesandmore.com... It wont let me link to it though... It just keeps taking me to the Hammond 125a page when I link to the Fender one...
Should work though... Primary impedance is 22,800 ohms, secondary is 8 ohms and 3.5w audio output. Pretty close to the Hammond 125a... Whatcha think?
I hate to keep bumping this... Should I start my own thread on my build?
Quote from: MetalUpYerEye on April 13, 2011, 11:31:13 PM
You have been tuning your trim pot to feed the 6111WA with 185 volts right?
Yeah, I've found that the SMPS likes to work best at 185v. I've tuned a few up to work at higher voltage, but always end up tweaking back down to 185v.
Quote from: MetalUpYerEye on April 14, 2011, 12:05:36 AM
Sorry I just realized... The xfmr that that link takes you to is a Hammond 125a... I was looking at the Fender P-T1750a at www.tubesandmore.com... It wont let me link to it though... It just keeps taking me to the Hammond 125a page when I link to the Fender one...
Should work though... Primary impedance is 22,800 ohms, secondary is 8 ohms and 3.5w audio output. Pretty close to the Hammond 125a... Whatcha think?
Yeah sounds good.
Quote from: MetalUpYerEye on April 14, 2011, 11:20:41 PM
I hate to keep bumping this... Should I start my own thread on my build?
Up to you, the benefit of keeping it all in one thread is the reference it builds up for future builders.
I'll stick with this thread for my questions. I'm also going to keep records of the parts list, etc. that I use so we can put them on the wiki. Any special source for 6112 and 6111wa tubes in the US? Is there a big difference between 6111 and 6111wa tubes?
6111 are rated at 150v, 6111WA are rated at 300v. In practice, 6111 will work just fine - tougher than buffalo hide. I'm in the UK, but buy my tubes from US ebay sellers.
Another Superfly. This one's got a 'Brake' pot instead of a master volume. I replaced R8 (470R) with a 500R linear panel mounted pot. The internal trimmer is still there - used to set the maximum voltage. The 'Brake' pot then varies the B+ between 110v and 190v.
(http://dl.dropbox.com/u/967492/SF5/SF0501.jpg)
(http://dl.dropbox.com/u/967492/SF5/SF0502.jpg)
(http://dl.dropbox.com/u/967492/SF5/SF0503.jpg)
Where do you get those protection "bars" from?
They look like cabinet handles that you might find at Home Depot, Lowe's or Ikea...
FC, where you do buy your sub mini tubes from? I've been searching ebay a bit and they seem a bit pricey ($12-15 each)... I'm also interested in your Pentaboost project and read that those tubes are supposedly cheap in cost as well but I can't find them for less than $15 each... :(
Ebay for tubes. Just keep looking for bargains, they do come up from time to time - but I'll probably outbid you. ;D I've built up quite a stockpile buying bargains.
Quote from: frequencycentral on April 25, 2011, 07:49:50 PM
Ebay for tubes. Just keep looking for bargains, they do come up from time to time - but I'll probably outbid you. ;D I've built up quite a stockpile buying bargains.
Not every time :-) I've got ten 6112 coming my way. I think I got them for about 34 dollars and 10 dollars in shipping.
Edit: damn you auto correct.
Quote from: Perrow on April 26, 2011, 07:48:23 AM
Not every time :-) I've got ten 6112 coming my way. I think I got them for about 34 dollars and 10 dollars in shipping.
Speak of the devil, mailman just handed me the box :-)
Quote from: Perrow on April 26, 2011, 08:06:35 AM
Quote from: Perrow on April 26, 2011, 07:48:23 AM
Not every time :-) I've got ten 6112 coming my way. I think I got them for about 34 dollars and 10 dollars in shipping.
Speak of the devil, mailman just handed me the box :-)
Damn your mailman, my auto re-direct must not be working.
Quote from: frequencycentral on April 26, 2011, 08:08:53 AM
Damn your mailman, my auto re-direct must not be working.
You'll damn him ever more when I've now opened the box, rechecked my confirmation mail and now sit here with not ten but twenty 6112 tubes bought for $29 and $14 in shipping (so $43 total). My memory is clouded by my current bronchitis (and a "slightly" bored four year old son, also with bronchitis).
They're a mix of full leads and trimmed (probably pulls) but I'm sure most of them will prove to work. Now if I could only find the time to actually finish this amp (hoping my Chinese 6111 substitutes will a) work and b) be good enough to make some nice sounds).
Quote from: Perrow on April 26, 2011, 08:26:28 AM
Quote from: frequencycentral on April 26, 2011, 08:08:53 AM
Damn your mailman, my auto re-direct must not be working.
You'll damn him ever more when I've now opened the box, rechecked my confirmation mail and now sit here with not ten but twenty 6112 tubes bought for $29 and $14 in shipping
Thats the thing... I don't need 20 of the darn things.. I'd be happy with two but have really been looking for 4 or 5 of them for like $15-20... Seems all I can find is one tube for $12 shipped or two for $15. Beyond that it goes to 10's, 20's, 100's... >:(
I guess i'll keep an eye out... What about the tube you used for your Pentaboost?
Hey wait! Perrow has more than he needs, MetalUpYerEye doesn't have any...........you guys should trade! Any spares I'll take if the price is right.
5672 from Ebay too, I bought a bulk amount years ago, I don't wanna sell any but I'll trade for 6111/6112.
I might wait to trade any of these and buy up on some 6111's and sell packages for this amp :-)
If you could make a 6111 and 6112 pack available i'd be in. But you'd need to sell the ones with full pins or test the ones without...
Even if you sold them for $12 a pair shipped you could still make your money back before you've sold half of them. That is, if you can get 20 or so 6111's for ~$45.
I'd be interested in a deal with the IRF740, BC547C and the two diodes as well... I rarely build and I don't have a stocked bench so finding one-off parts can be a pain in the ass for me... Basically the only stuff I have 'stocked' are resistors, some caps and 2n3904, 2n5088, j201's... As well as some jacks, pots, switches, etc. randomness.. :-X
Quote from: MetalUpYerEye on April 28, 2011, 07:06:29 PM
Even if you sold them for $12 a pair shipped you could still make your money back before you've sold half of them.
A statement that shows you haven't shipped anything out of (or even inside) Sweden :(
But it might hold at $14 or $15 (said without checking actual shipping costs but postage in Sweden is expensive, and out of Sweden even more so).
I'll see what I can do for buying 6111s or even 6021s, only found them quite a bit more expensive.
True, I have never shipped to or from Sweden...
I often forget that many of the people on this board are from other countries... Back to ebay to hunt for tubes I guess... If you guys will let me win an auction... ::)
FC - Sorry to be a bother... Looking at tubes on ebay I noticed that you originally said that a 6111 or 6021 could be used in place of the 7327... 6021 seems to be a bit cheaper... Any particular reason you've chosen to use 6111's in your builds over 6021?
Also... I just placed an order with Small Bear for some other stuff... But couldn't find any of the IRF740, uf4004 or the inductor available... I think I searched Tayda and they didn't have them either...
Quote from: MetalUpYerEye on May 04, 2011, 10:33:45 PM
Also... I just placed an order with Small Bear for some other stuff... But couldn't find any of the IRF740, uf4004 or the inductor available... I think I searched Tayda and they didn't have them either...
Tayda stocks the IRF740, but not the UF4004 yet (I've emailed them and they say they'll have them ASAP). Until then Futurlec is your friend.
Sweet! Futurlec has everything i'll need and I already have the caps for this... I just won 2 ebay auctions as well... One for a NOS 6112 and the other for a NOS 6021... :D Both are RCA and even come with the original boxes... :o And for only $2.50 each with $6.50 shipping... ::) They're the same seller so i'm gonna see if he'll combine shipping and save me a couple more bucks... Not much but would still be nice...
It makes me sick to think that i've paid $11 for 2 tubes when I could have bought a lot of 10 tubes for $25... I just don't need 10 of each of these... If my build works out I might do 2 more (one for my Brother, one for my Dad...) Time permitting of course...
I'm still planning on building the Pentaboost as well... Maybe as a permanent front end boost in my Superfly... We'll have to see. I was really planning on building the Pentaboost first so get my feet wet in submini's but the 6112 and 6021 auctions kind of jumped up on me...
I asked before but didn't get a response... Maybe its somewhere in this thread... How come you chose to use 6111wa instead of 6021 on most of your builds, FC?
Best source for NOS Tubes in the US is Vacuum Tubes, Inc. in Orlando, FL. Jim knows his tubes, has a huge inventory and is very reasonably priced. I have been buying from him for about 6 years, now. Tell him Steve from VintageToneUSA, in Orlando sent you. http://www.vacuumtubesinc.com/Products/VacuumTubes/NewTubes1603to8950.aspx (http://www.vacuumtubesinc.com/Products/VacuumTubes/NewTubes1603to8950.aspx)
Those tubes seem a bit overpriced... $10 for a 6111 and $22 for a 6112... $8 for a 6021 but they have the fabled 7327 for $10 each!
I just got an email from the ebay seller I won my auctions at. He's combined my shipping so $2.50 per tube plus $3.50 shipping = $8.50 for both tubes. ;D Not bad for buying single units I guess.
Quote from: MetalUpYerEye on May 07, 2011, 03:22:05 PM
Those tubes seem a bit overpriced... $10 for a 6111 and $22 for a 6112... $8 for a 6021 but they have the fabled 7327 for $10 each!
I just got an email from the ebay seller I won my auctions at. He's combined my shipping so $2.50 per tube plus $3.50 shipping = $8.50 for both tubes. ;D Not bad for buying single units I guess.
Depends what you're buying/your requirements are. I build for myself and for sale. I need reliability and a supplier who stands behind his/her product. If it's strictly a hobby, that may not be so important. Yes, that is good pricing and many good deal are out there. Bottom line is, Jim keeps his inventory current and absolutely stands behind his products. The fact the he's 20 mins. from my door is nice, too!
I noticed this in a video I saw earlier... A nixie style power supply module, fully built, 1.2-18v input with a 150-200v adjustable output... For $13 shipped. I might just do one of these instead of building the Nixie, although i'm setting myself up for problems by not following the layout... Is anyone making PCB's for the Superfly?
http://www.tayloredge.com/storefront/SmartNixie/PSU/index.html
the nixie on this thread is better and puts out more ma and voltage i belive. You may want to stick with it. My 2 cents.
Quote from: MetalUpYerEye on May 07, 2011, 11:42:05 AM
How come you chose to use 6111wa instead of 6021 on most of your builds, FC?
Easier to find, and cheaper. ;)
Quote from: frequencycentral on May 08, 2011, 07:48:41 PM
Quote from: MetalUpYerEye on May 07, 2011, 11:42:05 AM
How come you chose to use 6111wa instead of 6021 on most of your builds, FC?
Easier to find, and cheaper. ;)
Ahh ok. :D I was able to find both but since you're probably looking for large quantities of them 6111 is probably easier to find...
Quote from: zambo on May 08, 2011, 07:32:12 PM
the nixie on this thread is better and puts out more ma and voltage i belive. You may want to stick with it. My 2 cents.
They have a link to a nixie kit comparison chart on that website... It has the nixie used in this build on there and says that its has Iout Max of 10mA and Pout Watts are 1.8w. The smaller module has an Iout of 68mA and Pout of 11.5w...
I want to explore adding a second power tube to this thing once its built... How much current are these circuits drawing as is?
I'm soldering this one up right now (well not right NOW, I'm at work) on perfboard, but while here at work I looked up something on the schematic and suddenly realised I had the tubes mixed up :icon_evil:
So there'll be some desoldering and resoldering tonight ::)
BTW: Didn't use the IRF740 but rather an 18N50, the on resistance is 0.22R (18N50) instead of 0.48R (IRF740), meaning lots less heat :)
Also, got a lesson in temperature coefficients. Measured the tube heaters with my Ohm-meter and got about 6R and thought "f**k, that's 2A, that can't be right". But then when I connected my variable power supply and slowly turned up the amp regulator they, of course, heated up and the current stopped around 0.3A.
Quote from: Perrow on May 25, 2011, 04:20:03 AM
I'm soldering this one up right now (well not right NOW, I'm at work) on perfboard, but while here at work I looked up something on the schematic and suddenly realised I had the tubes mixed up :icon_evil:
So there'll be some desoldering and resoldering tonight ::)
BTW: Didn't use the IRF740 but rather an 18N50, the on resistance is 0.22R (18N50) instead of 0.48R (IRF740), meaning lots less heat :)
Also, got a lesson in temperature coefficients. Measured the tube heaters with my Ohm-meter and got about 6R and thought "f**k, that's 2A, that can't be right". But then when I connected my variable power supply and slowly turned up the amp regulator they, of course, heated up and the current stopped around 0.3A.
you can calculate the heater resistance from the data sheet. For example the 6111 says .3 do 6.3/.3 = 21ohms or 1.89 watts if you need to add a resistor for the heaters for any reason, like to use a 12v heater supply.
Quote from: Perrow on May 25, 2011, 04:20:03 AM
BTW: Didn't use the IRF740 but rather an 18N50, the on resistance is 0.22R (18N50) instead of 0.48R (IRF740), meaning lots less heat :)
Interesting! I await your results with anticipation!
I have parts on the way for this build as well. I'm going to pre-make a passive Baxandall and FMV tone stack to switch between the two and see what I like better.
I ordered all the same part numbers as the schematic though... I ordered everything from Futurlec, who have everything in stock that this project needs, minus the tubes and xfmr.
Come to think of it... I ordered the 100uh inductor from Futurlec too, but it looks much different from the one you've shown in pictures FC... Anyone tried it with that inductor?
I had no idea, but among the 21 tubes I recieved when I bought "20 pieces of 6112 tubes" from ebay where one (1) 6021 tube! ???
And with an amazing stroke of luck my fingers selected that one when I opened the drawer and picked what I thought were a 6112, so it turns out I can test my amp without resoldering :icon_mrgreen:
Quote from: frequencycentral on May 25, 2011, 07:31:51 PM
Quote from: Perrow on May 25, 2011, 04:20:03 AM
BTW: Didn't use the IRF740 but rather an 18N50, the on resistance is 0.22R (18N50) instead of 0.48R (IRF740), meaning lots less heat :)
Interesting! I await your results with anticipation!
Well, I have tested just the SMPS part without heatsink and after 10-20 seconds the 18N50 is barely warm to the touch ;D
Hey FC, am I correct thinking every resistor is 1/4 watt? Seems to my eyes (and when it comes to tubes they're not that good) that R1 (440 ohm) is taking a lot of beating for a 1/4 watt resistor.
Umm noob question. How do u get 185 volts out of a 9v battery? ???
Quote from: user on May 26, 2011, 01:19:09 PM
Umm noob question. How do u get 185 volts out of a 9v battery? ???
http://www.diystompboxes.com/smfforum/index.php?topic=74088.msg613311#msg613311
Quote from: Perrow on May 26, 2011, 10:52:52 AM
Hey FC, am I correct thinking every resistor is 1/4 watt? Seems to my eyes (and when it comes to tubes they're not that good) that R1 (440 ohm) is taking a lot of beating for a 1/4 watt resistor.
Never mind, made a model in LTSpice and got the answer :icon_cool:
Dissipation: 27.0901 mW
The answer is therefore that 1/4 watt resistor for R1 works great, and anybody wondering why should really investigate/study voltage dividers :)
Quote from: frequencycentral on May 25, 2011, 07:31:51 PM
Quote from: Perrow on May 25, 2011, 04:20:03 AM
BTW: Didn't use the IRF740 but rather an 18N50, the on resistance is 0.22R (18N50) instead of 0.48R (IRF740), meaning lots less heat :)
Interesting! I await your results with anticipation!
It does produce very little heat, but I bought my inductor from Futurlec (their power inductor) and can't get the HV over 100V (with tubes, without I've had no problem dialing in up to 200V), so I'm going to order some inductors from Mouser (as well as some IRF740, just to be sure).
If someone has Mouser part numbers for known working inductors I'd be grateful.
If anyone else had problems getting the voltage up (with load) and solved the problem I'd like to hear how.
As for how little heat the 18N50 produce, I've had the amp working for about five minutes and it was just warm to the touch (no heatsink).
You can get higher voltage out of the SMPS by reducing the value of R8 (470R on my layout) or increasing the value of R10 (220k on my layout). But be VERY CAREFUL, it's possible to get insanely high voltages that will look great on your DMM for a few minutes/seconds until the whole thing melts....... :icon_mrgreen: I'd recommend making only very small changes, see what happens, then make another very small change until you get what you want.
Quote from: frequencycentral on June 13, 2011, 02:59:33 PM
You can get higher voltage out of the SMPS by reducing the value of R8 (470R on my layout) or increasing the value of R10 (220k on my layout). But be VERY CAREFUL, it's possible to get insanely high voltages that will look great on your DMM for a few minutes/seconds until the whole thing melts....... :icon_mrgreen: I'd recommend making only very small changes, see what happens, then make another very small change until you get what you want.
I thought about that approach, maybe "inject" another trimmer to test, but I've also tried with a CMOS55 that doesn't look like it bothers about the "adjustable part" and only got about 150V. I'll give it a shot but I'll likely try new inductors as well (and double, or is that quadruple, check that I've got the UF4004 where it's supposed to be).
I've tried inductors pulled from computer power supplies but haven't really gotten any better results with them (unmarked so anyones guess what values they are), had to go by ear as to how much voltage I got as the DMM was all over the place with most of those inductors. Just thought today, while out walking, to test with my analog meter, perhaps it's not as easily confused.
I do have a standby switch mod. Short the connection between the collector and emitter of the transistor, the 555 stops, and you get a B+ of 12V. Let the tubes heat up, break the connection and the 555 starts and you'll get your regular B+.
Quote from: Perrow on June 13, 2011, 04:40:32 PM
I do have a standby switch mod. Short the connection between the collector and emitter of the transistor, the 555 stops, and you get a B+ of 12V. Let the tubes heat up, break the connection and the 555 starts and you'll get your regular B+.
Neat! I like it a lot!
Quote from: iccaros on June 14, 2011, 03:22:28 PM
Quote from: Perrow on June 14, 2011, 02:02:20 AM
Quote from: frequencycentral on June 13, 2011, 04:50:36 PM
Neat! I like it a lot!
Yeah, it's quite simple :)
Perrow, sound samples?
I've no speaker to speak of (pun intended), currently using a salvaged 2", maybe 3", speaker from a radio without any enclosure ::)
But there are sound samples on the first page IIRC. Also, as I've yet to "find" the voltage mine's not that loud.
Hi! I've got lot of epoxi dipped picking coils inductors :icon_eek: ???, I'll post photos tomorrow, I've never seen something like this before today...
just wondering if anyone has tried the Russian version of subminies, the 6N17B-V has a MU of 88 for example. The pin out is different
One more question about the transformer,
First in this low wattage situation, I do not believe that it matters, I do not think the tube will over dissipate, but curiosity is getting to me..
but according to the US NAVY NEET'S training and I believe Merlin's stuff, and giving this is class A I believe, I could be wrong.
190V^2/1.1watts = 32818 ohms per 1/2 of the transformer..
so I am curious, since I have not built one of these yet, If we place a 1ohm resistor on the cathode of the output tubes, we could read voltage across which would give us a 1 for 1 relationship to the current being drawn. or can someone measure the voltage off the cathode resistor (the 440 ohm) and it should be voltage/resistance = current.
Current at the cathode is composed of both screen and plate current. Some reading in the data sheets or assumptions can be made to estimate the screen current. But yes, measuring the voltage drop across a cathode resistor is a way to calculate cathode current. This is standard practice in biasing tubes.
Quote from: defaced on July 07, 2011, 12:33:23 PM
Current at the cathode is composed of both screen and plate current. Some reading in the data sheets or assumptions can be made to estimate the screen current. But yes, measuring the voltage drop across a cathode resistor is a way to calculate cathode current. This is standard practice in biasing tubes.
sorry for the misunderstanding, I am asking if someone who built this would measure this for me so I would have a better Ideal on how this is reacting to the 125A (2 & 5)8k load @ 8ohms, or did I miss something changing the pin out to the 22K taps in a post?
the optimum for the tubes would be 33K or am I wrong on that?
I am in the middle of sourcing parts for this, so this is all in the name of research.
bump
Quote from: frequencycentral on April 13, 2010, 07:22:39 PM
I noticed that too, but as this is virtually a straight copy of Doug H's Firefly I stuck to the Firefly schematic (http://i238.photobucket.com/albums/ff243/Casey4s/FireFly/FireflySchematic.jpg). I *suspect* the ohmage figure on the Firefly schematic refers to the maximum available from that transformer as opposed to the taps used. Maybe Doug could shed some light on it? The plate resistance of a 12AU7 is 6500 - 7700 ohms, so 8200 is pretty close. The plate resistance of a 6111WA is 4000 - 5000 ohm. So maybe there's a slighly better combination available. I did try different combinations including 2 and 4, with little difference THB. I'm currently building a Superfly with the addition of a tonestack and a master volume. :icon_biggrin:
Sorry to boost this
but new question along with my old.. :)
for the inducter does this look good?
http://www.mouser.com/ProductDetail/API-Delevan/DC780-104K/?qs=sGAEpiMZZMsg%252by3WlYCkU45muCuneYXkPP0ToNV1U6o%3d (http://www.mouser.com/ProductDetail/API-Delevan/DC780-104K/?qs=sGAEpiMZZMsg%252by3WlYCkU45muCuneYXkPP0ToNV1U6o%3d)
I was hoping that Dough or RG, PRR, Merlin would have an answer, the Firefly is using the 22K taps, This limits the current draw to 10% under the rated max for the 12au7, or at least close enough. I have always been told that output Independence should be about 10X your plate resistance, or somewhere in there. In this case it may not matter, as the SMPS may limit enough, or the tubes can handle more current than rated. Rick has had success so I know it works this way.
6111 ratings withe a 190v SMPS
190V^2/1.1watts = 32818 ohms
Firefly (12au7) with 265 B+
265^2 / 2.2 watts = 25536
Quote from: frequencycentral on February 27, 2011, 07:24:18 AM
@ Dan: Well they look right physically, but the ones I use are labelled '104'. I think inductor labelling is the same as cap labelling, so (to me at least, I'm happy to be corrected), the '101' markings don't look right.
@ Hides: I'm using 15mm nylon standoffs from Banzai.
in this case 101 = 100uh and 104 = 100000 uh, the first two numbers like capacitors, the last number is how many zeros to add. Unlike capacitors we do not move the decimal over 5 spaces.
http://how-to.wikia.com/wiki/How_to_identify_inductor_markings
Quote from: iccaros on July 07, 2011, 01:10:52 PM
Quote from: defaced on July 07, 2011, 12:33:23 PM
Current at the cathode is composed of both screen and plate current. Some reading in the data sheets or assumptions can be made to estimate the screen current. But yes, measuring the voltage drop across a cathode resistor is a way to calculate cathode current. This is standard practice in biasing tubes.
sorry for the misunderstanding, I am asking if someone who built this would measure this for me so I would have a better Ideal on how this is reacting to the 125A (2 & 5)8k load @ 8ohms, or did I miss something changing the pin out to the 22K taps in a post?
the optimum for the tubes would be 33K or am I wrong on that?
I am in the middle of sourcing parts for this, so this is all in the name of research.
See reply #199 (mine) - somewhere around page 10.
Use 20k + for this circuit.
Andy
Thanks, so did you use the 15K from the transformer you posted? I am in the states, so I could not find it here, but @ 9 pounds that is what $24 plush shipping and the hammond is only $34 here
Not to derail this thread/line of conversation but has anyone taken a stab at my full sized tube layout yet?
Only i'm a Transformer, PCB, Inductor, MOSFET & High Wattage Resistor away from being able to finish it...
Taylor?
Haven't had time I'm afraid. I ended up grabbing a Valve Jr. I am very curious about how it turns out though. Sorry! :icon_redface:
Quote from: Scruffie on July 13, 2011, 08:57:52 PM
Not to derail this thread/line of conversation but has anyone taken a stab at my full sized tube layout yet?
Only i'm a Transformer, PCB, Inductor, MOSFET & High Wattage Resistor away from being able to finish it...
Taylor?
you mean running off of SMTP or just using standard tubes, as the values are a basic firefly, its the supply and the subminis that make this interesting.
Once I have the power supply working I may do a test, I am also building a High Octane with sub mini tubes so I want to test that also..
Quote from: Taylor on July 13, 2011, 09:00:36 PM
Haven't had time I'm afraid. I ended up grabbing a Valve Jr. I am very curious about how it turns out though. Sorry! :icon_redface:
Wait... you purchased an amp over DIY?
(http://www.smh.com.au/ffximage/2008/02/06/body_snatchers_080128110655013_wideweb__300x210.jpg)
:icon_lol: No Worries.
Quote from: iccaros on July 14, 2011, 12:51:36 AM
Quote from: Scruffie on July 13, 2011, 08:57:52 PM
Not to derail this thread/line of conversation but has anyone taken a stab at my full sized tube layout yet?
Only i'm a Transformer, PCB, Inductor, MOSFET & High Wattage Resistor away from being able to finish it...
Taylor?
you mean running off of SMTP or just using standard tubes, as the values are a basic firefly, its the supply and the subminis that make this interesting.
Once I have the power supply working I may do a test, I am also building a High Octane with sub mini tubes so I want to test that also..
I mean the PCB layout I made several pages back, using an MAX1771 Charge Pump with Onboard Pots & a 12AU7 & AX7 to fit a 1590BB.
I bought a Max 1771 just to test that build, waiting for it to come in, I have lots of 555, from a EE project going back 10 - 15 years.. but wanted to test the different power setups, once I get it up and running I'll give a report
as for fitting in the little box... well that is too be seen, It may go into my Snoopy lunch box I just mounted a 2" 3watt speaker into..
Quote from: iccaros on July 14, 2011, 08:48:20 AM
I bought a Max 1771 just to test that build, waiting for it to come in, I have lots of 555, from a EE project going back 10 - 15 years.. but wanted to test the different power setups, once I get it up and running I'll give a report
as for fitting in the little box... well that is too be seen, It may go into my Snoopy lunch box I just mounted a 2" 3watt speaker into..
I beleive I sold you that MAX1771 :icon_mrgreen: I sent it last... Thursday? Wednesday Maybe? So it should arrive by tommorow i'd have thought.
I'm not actually putting mine in a 1590BB but that PCB should fit one, i've got a sheet metal case i've had lying around that should be just perfect.
Does anyone have a place to get a transformer suitable for this in the U.K. that isn't bluebell audio? They don't take paypal and have no ordering cart which is just a pain for me.
Quote from: Scruffie on July 14, 2011, 09:03:55 AM
I beleive I sold you that MAX1771 :icon_mrgreen: I sent it last... Thursday? Wednesday Maybe? So it should arrive by tommorow i'd have thought.
Na, customs is stupid in the states, my last package sat in NY for two weeks before being sent out to me.
I had forgotten who I bought that from.... been so long :icon_mrgreen:
I am getting ready in the next week to order two of OTPP5 from http://www.musicalpowersupplies.com/6.html (http://www.musicalpowersupplies.com/6.html) but that does not help you, I can see what they cost to actually ship if you need one though...
http://uk.rs-online.com/web/p/audio-transformer/2106475/ (http://uk.rs-online.com/web/p/audio-transformer/2106475/)*not sure if they take pay pal
Quote from: iccaros on July 14, 2011, 10:19:51 AM
Quote from: Scruffie on July 14, 2011, 09:03:55 AM
I beleive I sold you that MAX1771 :icon_mrgreen: I sent it last... Thursday? Wednesday Maybe? So it should arrive by tommorow i'd have thought.
Na, customs is stupid in the states, my last package sat in NY for two weeks before being sent out to me.
I had forgotten who I bought that from.... been so long :icon_mrgreen:
I am getting ready in the next week to order two of OTPP5 from http://www.musicalpowersupplies.com/6.html (http://www.musicalpowersupplies.com/6.html) but that does not help you, I can see what they cost to actually ship if you need one though...
http://uk.rs-online.com/web/p/audio-transformer/2106475/ (http://uk.rs-online.com/web/p/audio-transformer/2106475/)*not sure if they take pay pal
Ahh damn, well hopefully they get to you soon!
Haha, I can't even remember when it was, got the proof of postage knocking about somewhere in the pile though.
Yeah I just checked that link... $14 shipping, kindaaa pricey.
I'll have to register to RS later to see what shipping and pricing options they do, cheers for the link.
Quote from: iccaros on July 13, 2011, 06:57:35 PM
Thanks, so did you use the 15K from the transformer you posted? I am in the states, so I could not find it here, but @ 9 pounds that is what $24 plush shipping and the hammond is only $34 here
I used 22K on the 125A & 26.5 k on the RS transformer. (See reply 202 (http://www.diystompboxes.com/smfforum/index.php?topic=78302.msg716783#msg716783) ;) )
The RS transformer was < 1/2 the price of the Hammond 125A here (UK). It's gone up nearly 50% since I bought mine.
Andy
in the US, musical power supplies has a 22K 5 watt PP made just for the Firefly for $24, he charges strait shipping so I think it was $8 which is what USPS charged me to ship one to my brother.
new question, what is the rating for the inductor, I have a Radio shack 2 amp and a 1.5 amp from mouser, the 1.5 fit on the PCB layout, the 2A does not..
or do I need to order another one
I got mine working with the 2A inductor from RS (that was the only one they had in stock), but I had to move the inductor, mosfet/heatsink and 330uf cap because they wouldn't fit the layout.
so is that a no on the 1.5 amp?
I've only used the 2A radio shack inductor (nominally 100uH, my meter told me it was around 80uH), so I can't tell you anything about the 1.5A one. If you've got both I'd try both of them and see which works better.
Quote from: jaapie on July 17, 2011, 09:27:47 PM
I've only used the 2A radio shack inductor (nominally 100uH, my meter told me it was around 80uH), so I can't tell you anything about the 1.5A one. If you've got both I'd try both of them and see which works better.
Thanks
This is the RS one (http://rsk.imageg.net/graphics/product_images/pRS1C-2266705w345.jpg) but red.. not that it matters.. I got it to fit on the board, had Govmnt_Lacky etch me two, did a awesome job.
I will try the 1.5a on bread bard, in case it does a painful death..
Quote from: iccaros on July 17, 2011, 09:44:34 PM
Quote from: jaapie on July 17, 2011, 09:27:47 PM
I've only used the 2A radio shack inductor (nominally 100uH, my meter told me it was around 80uH), so I can't tell you anything about the 1.5A one. If you've got both I'd try both of them and see which works better.
Thanks
This is the RS one (http://rsk.imageg.net/graphics/product_images/pRS1C-2266705w345.jpg) but red.. not that it matters.. I got it to fit on the board, had Govmnt_Lacky etch me two, did a awesome job.
I will try the 1.5a on bread bard, in case it does a painful death..
Well I guess if your power supply you use is less than 1.5A... then it should be fine.
Silly but important question. ::)
Can someone provide a manufacturer or a link to the 1K trimmer that is used for Rick's board? I cannot find one that fits the footprint (larger than your standard Bourns 3386-series)
Thanks from noob-ville :P
@Greg, I used a Radio shack one, I had to straiten out the one leg to fit, but it was not so bad that it was in danger.
http://www.radioshack.com/product/index.jsp?productId=2062300 (http://www.radioshack.com/product/index.jsp?productId=2062300)
(http://rsk.imageg.net/graphics/product_images/pRS1C-2160209w345.jpg)
I am awaiting a transformer that does 22K to finish, so I will let you know any issues. but others that have completed this can weigh in..
First test of my SuperFly
(http://dl.dropbox.com/u/14312589/SuperFly1.jpg)
This is running thought a 70v line transformer (10watt) using the .65watt , 2.5 watt and common tap with 2.5 being center using a 8ohm on the 4ohm tap to give me about 16000 ohm CT.
It fats out, but that may be the transformer, Its only until I receive my transformers.
Just wondering does this get clean at all? I did use the bias adjust switch mod, but my switch could not take the iron and the 4.7K tap does not work, so I will fix that before I put it in a case.
I want to add a tone control, so That may be on the second build or a quick mod of this one
Thanks to Govmnt_Lacky, he etched me some boards.. Good work
Test video to review how it sounds and to ask if those tubes are suppose to shine this bright?
Thanks
Lessons learned building this amp
#1
Always connect the transformer to the right connections, on accident I connected to the 2.5 watt connection on the 20v side not the 70v of my line transformer.. Well let say It lets the smoke out
#2
create sokets for the tubes using this type of 8pin dip --> (http://dl.dropbox.com/u/14312589/6112%20Socket.png) as the tubes make better connection than with the spring type
I used the spring type for connecting to the board as you can see from a picture earlier in the thread. I would get lots of oscillation until I double socket-ed them, I am sure if you used non sprint types in the beginning you would have the better results..
#3
This amp is louder than you think, I need to do some measurements, but I am sure its close to 1.5 watts, maybe 2...
#4
try different tubes, the 6111 in the power position stays cleaner but the mode for bias control between 820R and 4.7K does not do much
6021 well they add overdrive of their own, and sound good, but so far they really go into oscillation, but that may be the batch I got.
6112 is a good preamp, but gives horrible output in comparison to the others. Its quieter than the 6111, I think that is due to current sourcing..
I believe my IRF740 was damaged when I hooked up the transformer wrong, it was the only time this thing get hot for me.. It smoked a little before I hit the power switch, but it works at 165v 6111 and 170v with the 6021 in the power amp section, but any higher and it starts to tremlo.. so I should replace that and test again.
I get lots of ground noise, buzzing and such, with the 6112, 6111 combo its not bad and is not as noticeable. I know I am getting oscillation but I need to connect the scope, may be after vacation when I box this up.
one for the tube glow..
(http://dl.dropbox.com/u/14312589/firefly%20side.jpg)
My tame shred master Rich Russell did me some soundclips: http://dl.dropbox.com/u/967492/Superfly%20Montage.mp3
(http://dl.dropbox.com/u/967492/SU%20%2B%20Pair/SU1.jpg)
Got mine working this morning! I'd finally soldered everything up yesterday, but i was getting some intense, gnarly motorboating and oscillations so i got discouraged and went to bed...turns out i hadn't grounded the OT shield or secondary. I fixed that, shortened and shielded a couple leads, and it works like a charm now! I need to do a few modifications (it's a bit muffled sounding at the moment and the distortion is kind of cruddy-- i think i need to filter out some bass in the beginning) but it sounds pretty great already. I ended up wiring the amp section point to point on terminal strips screwed into a block of wood-- now I've gotta figure out how to fit it into something.
My phone battery is dead now, but I'll try and take a couple pictures a bit later.
I changed out the coupling caps with the prescribed 0.022s (i had been using 0.047) and it sounds much, much better--the distortion isn't nearly as 'grainy' or muffled. I have a few questions regarding some refinements I'd like to make:
First of all, the most annoying problem has to do with what happens when i roll down my guitar's volume control. When the pot is between about 90% and 30%, a very loud and annoying hum dominates the signal. It isn't present when the guitar volume knob is all the way up, but as soon as i roll it down just a hair (where tend to keep it) the terrible hum joins the party. As I roll the knob down from there, the hum lessens with the signal to a certain point where the hum isn't too bad-- but the guitar is too low to really hear, either. I don't think it's an issue with the guitar wiring since it doesn't happen with any of my other amps, but it's odd that it only happens when the knob is rolled off slightly. For what it's worth, the 'chassis' is still a block of wood, although the input lead is shielded.
Secondly, the distortion is still kind of harsh sounding-- it sounds to me like a little LP filtering in the preamp might clear it up a little. Any suggestions on where to start trying (small) alterations? I'd prefer to stay away from adding a tone control at this point
Here're a couple of pictures:
http://a7.sphotos.ak.fbcdn.net/hphotos-ak-snc6/254785_10100171549934573_22201673_46643081_2026845_n.jpg (http://a7.sphotos.ak.fbcdn.net/hphotos-ak-snc6/254785_10100171549934573_22201673_46643081_2026845_n.jpg)
http://a6.sphotos.ak.fbcdn.net/hphotos-ak-ash4/224462_10100171549764913_22201673_46643078_193336_n.jpg (http://a6.sphotos.ak.fbcdn.net/hphotos-ak-ash4/224462_10100171549764913_22201673_46643078_193336_n.jpg)
Quote from: jaapie on July 31, 2011, 02:29:38 PM
Here're a couple of pictures:
(http://a7.sphotos.ak.fbcdn.net/hphotos-ak-snc6/254785_10100171549934573_22201673_46643081_2026845_n.jpg)
(http://a6.sphotos.ak.fbcdn.net/hphotos-ak-ash4/224462_10100171549764913_22201673_46643078_193336_n.jpg)
"The Log (http://en.wikipedia.org/wiki/Les_Paul#Early_career)"?
another update-
I think the volume control thing is just a quirk of the guitar wiring that i haven't noticed before. I don't usually play with as much gain as I'm able to with this amp, so i think the hum is just more apparent now.
I also added a cobbled-together one-knob BF tonestack to give it more of a midscoop. There's a good bit less gain than there was before, but the tone is spot-on and there's still a good bit of bite, especially on chords. Maybe I should check out adding an opamp recovery stage before the volume control to give it a little more dirt?
I always remove the 470k grid stopper when I add a tonestack. Get you a bit of gain back.
I pulled the grid stopper out, but it actually sounded cleaner so I put it back in! The more I play around with it, the more I like it even with less gain. I may see about adding a cathode bypass cap to the second gain stage, but it works great just as is! Thanks for a fun, great sounding little circuit dude!
eh, I just looked at the "Superfly Special" schematic with the tone control, and I see maybe you meant the resistor and capacitor... maybe I'm a bit too literal! I'll try it tomorrow taking both of them out and see what happens.
Good work Jappie, I found that I like the dual 6011 tubes if I am adding pedals, but the 6112 and 6021 If I am going to use it on its own..
PS I like your bread board..
Help, I am getting a stutter,
My first try to fix it was to pull and move wiring, but no good, then I soldered the tubes to the board... Nope (it is louder .. now)
So before I look at the IFR 740, which is what I think it is,
can having the output transformer inside this lunch box (metal) this way cause this problem?
(http://dl.dropbox.com/u/14312589/IMG_0254.jpg)
here is a video of the meter, you can not hear the stutter (don't know why?), but you can see it on the meter. This is reading DC voltage for the B+ off the output transformer
http://dl.dropbox.com/u/14312589/MVI_0256.AVI (http://dl.dropbox.com/u/14312589/MVI_0256.AVI)
If I have my guitar at full volume or no volume its not as noticeable, but when I turn down the guitar it starts to stutter. I would agree that it is oscillation, and I have changed out tubes and lowered voltage.. No joy. I may try a 1 meg across the input jack.
Any and all suggestions are appreciated, thanks
All right, I finally finished building everything into the radio chassis last night and got it up and running. I still need to give it a couple tweaks (wired up the tone pots backwards, which is interesting!) but it seems to be working well, with one caveat: The heaters won't heat unless the amp is put into standby before the HV is turned on (I know that this is good practice anyway, but I didn't have this issue on the breadboard. Here's a breakdown of what happens:
When the amp is powered on without being put in standby first, the 12v node of the power supply as well as any node in the circuit that is supposed to be at 12v (i.e. heaters, Nixie supply, even the power switch) drops to 0v. Strangely, however, the HV taps are all about right. This is obviously really screwy and I'm pretty sure it's against the law to make energy from nothing. Anyway, I don't think tubes like that high voltage when they're cold.
If I put the amp in standby as per the mod mentioned a while back in this thread (shorting the emitter and collector of the BJT), the 12v doesn't drop to 0 and the tubes heat up properly. When standby is switched off, the HV comes on as it should and everything works properly.
I'm excited that it works, but I'm curious as to what could be causing this to happen. Does anyone have any ideas?
I think the SMPS draws more current when it starts up than when it's running. So when you turn it on the SMPS is fighting the heaters for ma - and winning, as the heaters heat up relatively slowly. I've never had this issue. What's the ma rating of your PS?
That's what i thought was happening too, but it's strange that it didn't happen before. The wallwart I'm using is rated 1A, so i should have plenty of current, right?
Glad to see that someone has use of my stand-by mod :-)
Here's some more pictures:
http://a4.sphotos.ak.fbcdn.net/hphotos-ak-snc6/223701_10100177480834003_22201673_46747679_3889267_n.jpg (http://a4.sphotos.ak.fbcdn.net/hphotos-ak-snc6/223701_10100177480834003_22201673_46747679_3889267_n.jpg)
http://a2.sphotos.ak.fbcdn.net/hphotos-ak-snc6/263378_10100177481003663_22201673_46747684_1740590_n.jpg (http://a2.sphotos.ak.fbcdn.net/hphotos-ak-snc6/263378_10100177481003663_22201673_46747684_1740590_n.jpg)
http://a2.sphotos.ak.fbcdn.net/hphotos-ak-ash4/281656_10100177481233203_22201673_46747690_5512925_n.jpg (http://a2.sphotos.ak.fbcdn.net/hphotos-ak-ash4/281656_10100177481233203_22201673_46747690_5512925_n.jpg)
Quote from: jaapie on August 09, 2011, 02:39:47 PM
Here's some more pictures:
http://a4.sphotos.ak.fbcdn.net/hphotos-ak-snc6/223701_10100177480834003_22201673_46747679_3889267_n.jpg (http://a4.sphotos.ak.fbcdn.net/hphotos-ak-snc6/223701_10100177480834003_22201673_46747679_3889267_n.jpg)
http://a2.sphotos.ak.fbcdn.net/hphotos-ak-snc6/263378_10100177481003663_22201673_46747684_1740590_n.jpg (http://a2.sphotos.ak.fbcdn.net/hphotos-ak-snc6/263378_10100177481003663_22201673_46747684_1740590_n.jpg)
http://a2.sphotos.ak.fbcdn.net/hphotos-ak-ash4/281656_10100177481233203_22201673_46747690_5512925_n.jpg (http://a2.sphotos.ak.fbcdn.net/hphotos-ak-ash4/281656_10100177481233203_22201673_46747690_5512925_n.jpg)
Nice, I like the reuse of radio. ;D
Quote from: frequencycentral on May 25, 2011, 07:31:51 PM
Quote from: Perrow on May 25, 2011, 04:20:03 AM
BTW: Didn't use the IRF740 but rather an 18N50, the on resistance is 0.22R (18N50) instead of 0.48R (IRF740), meaning lots less heat :)
Interesting! I await your results with anticipation!
Got mine working at 165V with the 18N50 and Futurlecs 100uH power inductor, on for at least five minutes without heatsink on the 18N50 and it's just warm to the touch ;D
Quote from: Perrow on May 25, 2011, 04:20:03 AM
Got mine working at 165V with the 18N50 and Futurlecs 100uH power inductor, on for at least five minutes without heatsink on the 18N50 and it's just warm to the touch ;D
@Perrow
so you used this one ? http://www.futurlec.com/Components_Others/IND100.shtml
Thanks for the updates.. :)
I think he meant this one
http://www.futurlec.com/Components_Others/PIND100.shtml (http://www.futurlec.com/Components_Others/PIND100.shtml)
i ordered a few of the ones you posted, and they're about the size of a 1/4w resistor-- i seriously doubt that they could withstand the high voltage (I think someone else a few pages back was having problems using that inductor).
On the other hand, I used the smaller inductors as a filter so i could use a 3.5in full-range speaker with my superfly (to filter out freqencies abouve ~5k and very roughly emulate the rolloff of a guitar speaker).
cool, Making an order, I plan on making a few of these as Christmas Gifts this year.. I did see the post earlier, but I thought maybe with the MOSFET change it made it work..
Not to sound stupid, I am.. But trying not to be.. :)
I bough a few of those 3 watt 3 something inch full range speakers, Which I am making some small Cabinets for,which size inductor did you use?
Thanks
Quote from: jaapie on August 22, 2011, 10:41:17 AM
I think he meant this one
http://www.futurlec.com/Components_Others/PIND100.shtml (http://www.futurlec.com/Components_Others/PIND100.shtml)
That's the one.
I wound up using a 190µH because i broke the other ones I had (a couple 100µH and a 120µH) trying to fit them inside the speaker cable plug. I was shooting for 220-250µH to roll off above ~5-6kHz...the 190µH rolls off above 7kHz, which is a little too bright for my taste (especially with the tiny, bassless speaker). As it is it still sounds a lot better than my little Marshall MS-2 with the same sized speaker, but it really sounds great through a full-sized guitar cab. I've been playing it through an ancient 15" Vox closed-back bass cab and I love it...although there is some charm to the rattiness of the tiny speaker.
Here's the calculator i used to figure out what value of inductor to use:
http://www.the12volt.com/caraudio/crosscalc.asp (http://www.the12volt.com/caraudio/crosscalc.asp)
The inductor goes in series with the speaker. I didn't have space for an extra speaker jack, so I soldered the inductor inside a 1/4" plug and then soldered about 6" of speaker cable to the plug and the terminals of the little speaker. That way I don't have to worry about switching the filter in and out, I leave the little speaker plugged in anytime I'm not using a bigger cab (the main reason I put the speaker in it was to decrease the chances of turning it on without a load...the speaker jack is right next to the power switch).
thanks,
I have three speakers I tested this with, a 12" Celeston Vintage 30, a Red Coat Wizard 12" and my Marshall 4x12... nice...
Quick question... how come you're using taps 2 & 5 on the output transformer but the Firefly build guide uses 2 & 4... i'm connecting this to an 8ohm speaker to test it.
On to that PCB layout I did... got a board kindly donated by Markeebee today (Thanks Mark!) and i'm gunna say not to build it, unless you don't mind offboard wiring. I'm gunna use and verify it (or not as the case may be) but mounting on the back of the PCB just takes up too much depth in an standard enclosure so i'll redesign it with the tubes the right way round this time and pots on the same side.
Thankfullly my enclosure is deeper than most so I can get away with it, but it's an odd enclosure.
Hopefully all being well, i'll have an (out the box at least) 12AX7 & U7 firefly verified by tommorow night!
Quote from: Scruffie on September 03, 2011, 02:25:32 PM
Quick question... how come you're using taps 2 & 5 on the output transformer but the Firefly build guide uses 2 & 4... i'm connecting this to an 8ohm speaker to test it.
On to that PCB layout I did... got a board kindly donated by Markeebee today (Thanks Mark!) and i'm gunna say not to build it, unless you don't mind offboard wiring. I'm gunna use and verify it (or not as the case may be) but mounting on the back of the PCB just takes up too much depth in an standard enclosure so i'll redesign it with the tubes the right way round this time and pots on the same side.
Thankfullly my enclosure is deeper than most so I can get away with it, but it's an odd enclosure.
Hopefully all being well, i'll have an (out the box at least) 12AX7 & U7 firefly verified by tommorow night!
I'll wait, as I just was ready to etch your board this weekend, as I have three days off.
I was wondering if you would mind, I got some 6N2P-EV, which are close to a 12ax7 but require 6.3 voltes between the 4 and 5 pin instead of 12. I think in yours you put 4 and 5 together and 9 to ground, but if you could make 4 to a jummper, I could try it with these tubes
Thanks
Also use the ratio that gives 22K. I have used it @ 10K, but 22K @ that voltage is what the math shows..
I use http://www.musicalpowersupplies.com/ OT5PP, I buy them in lots of 2 for $51 shipped.
Not sure I follow you... I don't mind doing it but if you read the thread, I had enough trouble with heater wiring already so you might need to make it a little clearer for me :icon_mrgreen:
Yes i'd wait, even if you do build this version it'd be best I verified it before you wasted your time.
What you could do is wire the pots on the component side of the board, but just stick the middle leg in and flip the outside lugs with wires to the alternate hole so sorta semi-board mounted The tube socket should be okay on the back depth wise, if you can solder it in that way. This may be an idea if you want to build this soon as i'm not sure when i'll have time to do the new layout, could be tommorow, could be 3 months.
I saw your heater issues
there are two ways to wire two tubes for 12volts one is in series of each other using the parallel wiring in the tube (the top half of the drawing)
The other being in parallel using the tubes series internal wiring, the second half of the drawing.
(http://dl.dropbox.com/u/14312589/12V%20heaters%20.jpg)
But looking at these if you did the second half then modifing like this
(http://dl.dropbox.com/u/14312589/russian%2012v%20heaters.jpg)
would allow me to jumper between ping 5 of tube one and pin 4 of the next.
This would allow the use of more tubes types.
Tell you what i'll do... i'll add 4 pads on the tracks between the tubes so you can cut them and jumper how you like. That way anyone building with standard tubes doesn't have to add jumpers but it's still simple for people that want to use other tubes.
cool, thanks
No worries :)
Now does anyone have an answer to my transformer taps question?
use the 22K:8 ohm ratio..
I modified my answer above, but you might have missed it.
Think of the transformer as a plate resister, which helps control how much current can pass, at 22K you keep current with in 80% of max dissipation
Ahhh I did miss that yeah, 2 & 4 it is then!
One other thing... I only have a 10k Trimmer, what values should I change the resistors in the voltage divider to?
Right... well i'm glad I tested it without the tubes and transformer.
So first off I was just getting 12V, couldn't work out why... and I still don't know, came back to the computer to check i'd got everything right and I had...
Plugged it back in and the voltage was fluctuating around so I stuck my meter on to the High voltage setting... and it settled around 500V, pretty sure I heard a hissing sound.
So... now i've put the trim back the other way, the voltage is fluctuating around 100-200V Have I just killed my high voltage caps, they look okay, it all looks fine, could it be a low battery in the meter causing weird readings? Or do I need to replace all the Charge Pump components.
Edit: It seems to charge up and shoot up to around 250V then drop back down again in incriments over a few seconds to 100Vish and repeat this pattern, tried it with a second multimeter and it was much the same.
Is this poor layout (may well be, I did try and keep to the MAX1771 article reccomendations) burnt out parts, or is it one of the few value subs I made - 47uF instead of 100uF Cap off the 12V, assumed this was just filtering and a 10k Trim instead of 5k... I also used one of the smaller inductors due to the bigger one not fitting the layout properly... also the 1M5 resistor is just a regular carbon film resistor, shouldn't it be high voltage? Wasn't noted so on Ricks schematic.
Oh and for anyone that builds one of these... don't have a few drinks get curious as to what that voltage feels like :icon_mrgreen: it feels Exactly how you think it'll feel.
my superfly does the same thing once I get over 120 volts, my RMS meter shows one voltage but it has a meter under the numbers that keep jumping.
I think I have a bad part, maybe a cap somewhere, but have not found it yet.
Quote from: iccaros on September 04, 2011, 12:58:11 AM
my superfly does the same thing once I get over 120 volts, my RMS meter shows one voltage but it has a meter under the numbers that keep jumping.
I think I have a bad part, maybe a cap somewhere, but have not found it yet.
This wont settle on any voltage.
I did realise that i'd left the rest of the circuit hooked up though with no tubes or transformer, hopefully after I lift the resistor joining it, things will settle down... or not as the case may be.
If not I assume bad layout or buggered caps... I get a steady 12V up untill the diode, after the diode, the voltage is all over the place.
My dmm won't measure the smps correctly, I think the high frequency messes it up. My analog meter does the trick. Old tech not so easily fooled by a measly 555 ;D
Quote from: Perrow on September 04, 2011, 04:11:52 AM
My dmm won't measure the smps correctly, I think the high frequency messes it up. My analog meter does the trick. Old tech not so easily fooled by a measly 555 ;D
Oh really? This may well be the issue!
Well of course i'm using a MAX1771 here but my DMM is a cheapie one (thing doesn't even have the right impeadance to measure V.Refs with out weird readings alot of the time).
I don't have anything else to test it with though... and I can't just guess what voltage i'm giving the tubes really... dilemma.
Success bad output cap on the power supply.. no more oscillation, will put pics and sound tomorrow.. :icon_mrgreen:
Quote from: Perrow on September 04, 2011, 04:11:52 AM
My dmm won't measure the smps correctly, I think the high frequency messes it up. My analog meter does the trick. Old tech not so easily fooled by a measly 555 ;D
I have a Fluke that has no issues, but it is True RMS..
My Radio Shack has no real issues, floats 1 and 10's volts but the hundreds are stable, so I can see that I am between 170 and 180v
my $1.98 Harbor Freight just looks at me.. :)
hey,
I am lying with a broken leg, planning to try this build, going through the schems and parts.
Do you think it is a good idea to build this on vero? I don't etch and am too impatient for perf, so I am doing most of my builds on vero. I am thinking of two separate boards: one 555 power and one amp section.
I am not really concerned to make it small (my first layout sketches go about 9x20 each board and I am OK with the size) but I've seen here mentioned that the circuit could be sensitive to parts a trace placing. So I am not sure if the long and wide strips of the vero wouldn't cause any problems. What do you think?
Quote from: lopsided on September 05, 2011, 05:23:41 PM
hey,
I am lying with a broken leg, planning to try this build, going through the schems and parts.
Do you think it is a good idea to build this on vero? I don't etch and am too impatient for perf, so I am doing most of my builds on vero. I am thinking of two separate boards: one 555 power and one amp section.
I am not really concerned to make it small (my first layout sketches go about 9x20 each board and I am OK with the size) but I've seen here mentioned that the circuit could be sensitive to parts a trace placing. So I am not sure if the long and wide strips of the vero wouldn't cause any problems. What do you think?
Rick did an outstanding job with vero, look through the tread and all of Ricks threads, as he does an outstanding job of documenting his build
Quote from: iccaros on September 05, 2011, 06:50:03 PM
Quote from: lopsided on September 05, 2011, 05:23:41 PM
hey,
I am lying with a broken leg, planning to try this build, going through the schems and parts.
Do you think it is a good idea to build this on vero? I don't etch and am too impatient for perf, so I am doing most of my builds on vero. I am thinking of two separate boards: one 555 power and one amp section.
I am not really concerned to make it small (my first layout sketches go about 9x20 each board and I am OK with the size) but I've seen here mentioned that the circuit could be sensitive to parts a trace placing. So I am not sure if the long and wide strips of the vero wouldn't cause any problems. What do you think?
Rick did an outstanding job with vero, look through the tread and all of Ricks threads, as he does an outstanding job of documenting his build
Rick made Perf layouts, not Vero.
Sorry to hear the leg's busted! Urmm... I dunno, depends on your layout skills as to building it on vero, no reason it shouldn't work though.
Quote from: lopsided on September 05, 2011, 05:23:41 PM
hey,
I am lying with a broken leg, planning to try this build, going through the schems and parts.
Do you think it is a good idea to build this on vero? I don't etch and am too impatient for perf, so I am doing most of my builds on vero. I am thinking of two separate boards: one 555 power and one amp section.
I am not really concerned to make it small (my first layout sketches go about 9x20 each board and I am OK with the size) but I've seen here mentioned that the circuit could be sensitive to parts a trace placing. So I am not sure if the long and wide strips of the vero wouldn't cause any problems. What do you think?
Start here: Nixie SMPS Vero (http://www.aronnelson.com/gallery/main.php?g2_view=keyalbum.KeywordAlbum&g2_keyword=Rick+frequencycentral+555+SPMS+layout+nixie+tube+power+supply&g2_itemId=42214)
Then do a design for the "missing" parts.
Edit: Break a leg, no wait, you already did that ;D
Quote from: Perrow on September 06, 2011, 02:13:07 AM
Start here: Nixie SMPS Vero (http://www.aronnelson.com/gallery/main.php?g2_view=keyalbum.KeywordAlbum&g2_keyword=Rick+frequencycentral+555+SPMS+layout+nixie+tube+power+supply&g2_itemId=42214)
Then do a design for the "missing" parts.
Edit: Break a leg, no wait, you already did that ;D
thanks guys and thanks for the link. I often forget about our galleries here.
I guess I'll start with the SMPS and see if I can make it work. And then continue with the amp.
The leg is killing me. It doesn't hurt much but I have to stay at my parents' (I live on fourth floor with no elevator) until they allow me to step on the leg. I basically just took my guitar and notebook but left the amp and DIY stuff at my place. So it's all planing future builds for me now.
Quote from: lopsided on September 06, 2011, 04:40:40 PM
thanks guys and thanks for the link. I often forget about our galleries here.
I guess I'll start with the SMPS and see if I can make it work. And then continue with the amp.
The leg is killing me. It doesn't hurt much but I have to stay at my parents' (I live on fourth floor with no elevator) until they allow me to step on the leg. I basically just took my guitar and notebook but left the amp and DIY stuff at my place. So it's all planing future builds for me now.
I actually googled something like "nixie smps vero" and that was the first or so result.
I can think of many worse fates than spending a week or two with a guitar and DIYLC ;D
I'm currently verifying my new layout for this project, got the smps working today and fixed at least three problems around the tubes. The smps was probably working already, but one of the OTs connections had a solder bridge to ground that I found and fixed.
While going over the board with a magnifying glass I then spotted two component legs that were not soldered in :icon_eek:
I still got no sound and only after leaving "the shed" realized I have the gain and volume pots connected incorrectly, so hoping that is the last error (yeah right) I might have it rocking tomorrow.
Finally, a debugging tip; to verify that the 555 is ticking along as it should (at least verify to some degree), add a 10uF or 22uF cap in parallel with C4 and solder in a led in series with a resistor between leg 3, of the 555, and ground (pin 1) and remove the MOSFET (IRF740). You should be able to see the led blinking. If C4 isn't broken the 555 should now be verified.
Why do you guys insist on building these in such large enclosures? ;)
(http://i832.photobucket.com/albums/zz249/Perrow_MLP/Builds/House%20fly/Gloryshot.jpg)
I'll include a gutshot in this thread.
(http://i832.photobucket.com/albums/zz249/Perrow_MLP/Builds/House%20fly/Gutshot.jpg)
More info coming, just got to present it in a way that'll make sense to someone else than me :)
Hey, I had a sweet 60 year old radio lying around dying for a new life. Plus, now I've got room for a little speaker and a 12v battery :)
@Perrow,
I think that is a pretty sweet build. Being able to squeeze that into a 1590A is phenomenal work!! :o
Perhaps you can help me understand what is the need for such "compactness" of the amp ???
Do you plan on using it strictly as some form of headphone amplifier? A tiny cabinet to drive?
Was it merely a challenge that needed conquering? I can't wrap my head around the need for such smallness... please enlighten me ;)
Quote from: Govmnt_Lacky on September 15, 2011, 11:12:30 AM
@Perrow,
...
I can't wrap my head around the need for such smallness... please enlighten me ;)
The short answer is: The devil told me to :icon_twisted:
The slightly longer answer is that I thought about building this and was looking at Ricks layout and thought; "I think I'll draw a schematic for just the SMPS, maybe I'll learn something, and maybe it'll be nice to have separate if and when I decide to build this".
Said and done I did a layout for just the SMPS and, hey, this could be quite compact. Redid the layout a couple of times and suddenly thought, I wonder if I could stack two boards and make this fit into a 1590A (was looking at the 1590A thread ever so often and admiring their work).
Fast forward some six or seven months and I don't know how many hours of redrawing this baby in DIYLC, learning how to etch sourcing parts and I can finally post my own 1590A build ;D
Its nice but I think I would like mine in a altoids can. The small one :icon_wink: Man thats some sweet work on that. Truly awe inspiring!
Right... well, my layout works to a point I know that much now.
I wont call it quite verified, I get guitar through but oscillation builds up as the tubes warm up however i'm hoping this is just due to my supply being only rated for 300mA (I did find a 500mA supply but it's Centre Positive... and put out 13.5V instead of the 12.6V it said :( ) rather than a layout issue, that and it's just a big mess of wires at the moment.
Anyway, now I know I can get it to work, i'll start on a new layout with the tubes and pots mounted the right way this time and space some things a bit better.
Quote from: Perrow on September 15, 2011, 10:26:17 AM
Why do you guys insist on building these in such large enclosures? ;)
I like my large enclosure.. I am putting a 3" speaker in mine :)
(http://dl.dropbox.com/u/14312589/LunchBox%20SuperFly.jpg)
the lunch box is sweet!
Quote from: Scruffie on September 21, 2011, 08:51:32 PM
Right... well, my layout works to a point I know that much now.
I wont call it quite verified, I get guitar through but oscillation builds up as the tubes warm up however i'm hoping this is just due to my supply being only rated for 300mA (I did find a 500mA supply but it's Centre Positive... and put out 13.5V instead of the 12.6V it said :( ) rather than a layout issue, that and it's just a big mess of wires at the moment.
Anyway, now I know I can get it to work, i'll start on a new layout with the tubes and pots mounted the right way this time and space some things a bit better.
Okay... now i'm getting somewhere!
Once I turned the voltage up past 200V the Oscillation stopped and I now have a working full tube Superfly! (well apart from the odd backwards pot but... ah well)
Now... some things i've noticed that I wanna check on, my 12AU7 is noticeably hotter to the touch than the AX7, is that normal? It's not burning my fingers but I can feel a difference in heat.
The IRF840 in the SMPS is getting a bit hot to the touch too after a few minutes of playing, is this down to my weak mA supply or something I should be concerned about... I recall Rick said his MAX1771 ran pretty cool. Admittedly my Voltage does seem to fluctuate a little bit but it doesn't seem to have done any harm so far.
I'm gunna make the new layout for a switchable Baxandall Tone Control I think if I can & add a Standby Switch, i've already shrunk down the Charge Pump considerably while allowing more space for the components that need it and cut the board space to make it easier to fit a 1590BB. I may also make it so the tube heaters are wired seperatley (like on the actual Firefly) to save room and for a hopefully a tidy build with less chance of issue.
Quote from: Scruffie on September 22, 2011, 05:16:12 AM
Quote from: Scruffie on September 21, 2011, 08:51:32 PM
Right... well, my layout works to a point I know that much now.
I wont call it quite verified, I get guitar through but oscillation builds up as the tubes warm up however i'm hoping this is just due to my supply being only rated for 300mA (I did find a 500mA supply but it's Centre Positive... and put out 13.5V instead of the 12.6V it said :( ) rather than a layout issue, that and it's just a big mess of wires at the moment.
Anyway, now I know I can get it to work, i'll start on a new layout with the tubes and pots mounted the right way this time and space some things a bit better.
Okay... now i'm getting somewhere!
Once I turned the voltage up past 200V the Oscillation stopped and I now have a working full tube Superfly! (well apart from the odd backwards pot but... ah well)
Now... some things i've noticed that I wanna check on, my 12AU7 is noticeably hotter to the touch than the AX7, is that normal? It's not burning my fingers but I can feel a difference in heat.
The IRF840 in the SMPS is getting a bit hot to the touch too after a few minutes of playing, is this down to my weak mA supply or something I should be concerned about... I recall Rick said his MAX1771 ran pretty cool. Admittedly my Voltage does seem to fluctuate a little bit but it doesn't seem to have done any harm so far.
I'm gunna make the new layout for a switchable Baxandall Tone Control I think if I can & add a Standby Switch, i've already shrunk down the Charge Pump considerably while allowing more space for the components that need it and cut the board space to make it easier to fit a 1590BB. I may also make it so the tube heaters are wired seperatley (like on the actual Firefly) to save room and for a hopefully a tidy build with less chance of issue.
Some Thoughts to what your are seeing...
From reading, This is how I understand it and could be wrong..
the inductor will ramp up to its max current in a given time frame, which based off the turn on resistance of the IFR840 is very low, which makes it fast, compared to the 740. you set voltage by adjusting the duty cycle of the PWM you are getting from the oscillator. If the duty cycle is longer than it takes to max the inductor the IFR is stuck with the extra current, which becomes heat.
In the original SuperFly this was handled with a heat-sink. Others have noted that raising the value of the inductor can help with this, say a 200mH or so, extending the time before the inductor pushes back.
As for Oscillation, I would look at the cap values, as they will smooth out the ripple based on the duty cycle of the IFR, and
As for one tube getting hotter than the other, I have an IR thermometer I use to monitor them, I find that one tube is always hotter than the others, but as long as they do not go near bulb max as listed in the datasheet I do not worry.
All of the reading I have done, also point out that you may want a 1A Power supply, but if its working and the supply is not getting hot, then don't worry. :)
But using the IRF840 and a larger inductor (amprage along with ratings) should get more current through to the tubes..
Quote from: iccaros on September 22, 2011, 06:30:33 AM
Quote from: Scruffie on September 22, 2011, 05:16:12 AM
Quote from: Scruffie on September 21, 2011, 08:51:32 PM
Right... well, my layout works to a point I know that much now.
I wont call it quite verified, I get guitar through but oscillation builds up as the tubes warm up however i'm hoping this is just due to my supply being only rated for 300mA (I did find a 500mA supply but it's Centre Positive... and put out 13.5V instead of the 12.6V it said :( ) rather than a layout issue, that and it's just a big mess of wires at the moment.
Anyway, now I know I can get it to work, i'll start on a new layout with the tubes and pots mounted the right way this time and space some things a bit better.
Okay... now i'm getting somewhere!
Once I turned the voltage up past 200V the Oscillation stopped and I now have a working full tube Superfly! (well apart from the odd backwards pot but... ah well)
Now... some things i've noticed that I wanna check on, my 12AU7 is noticeably hotter to the touch than the AX7, is that normal? It's not burning my fingers but I can feel a difference in heat.
The IRF840 in the SMPS is getting a bit hot to the touch too after a few minutes of playing, is this down to my weak mA supply or something I should be concerned about... I recall Rick said his MAX1771 ran pretty cool. Admittedly my Voltage does seem to fluctuate a little bit but it doesn't seem to have done any harm so far.
I'm gunna make the new layout for a switchable Baxandall Tone Control I think if I can & add a Standby Switch, i've already shrunk down the Charge Pump considerably while allowing more space for the components that need it and cut the board space to make it easier to fit a 1590BB. I may also make it so the tube heaters are wired seperatley (like on the actual Firefly) to save room and for a hopefully a tidy build with less chance of issue.
Some Thoughts to what your are seeing...
From reading, This is how I understand it and could be wrong..
the inductor will ramp up to its max current in a given time frame, which based off the turn on resistance of the IFR840 is very low, which makes it fast, compared to the 740. you set voltage by adjusting the duty cycle of the PWM you are getting from the oscillator. If the duty cycle is longer than it takes to max the inductor the IFR is stuck with the extra current, which becomes heat.
In the original SuperFly this was handled with a heat-sink. Others have noted that raising the value of the inductor can help with this, say a 200mH or so, extending the time before the inductor pushes back.
As for Oscillation, I would look at the cap values, as they will smooth out the ripple based on the duty cycle of the IFR, and
As for one tube getting hotter than the other, I have an IR thermometer I use to monitor them, I find that one tube is always hotter than the others, but as long as they do not go near bulb max as listed in the datasheet I do not worry.
All of the reading I have done, also point out that you may want a 1A Power supply, but if its working and the supply is not getting hot, then don't worry. :)
But using the IRF840 and a larger inductor (amprage along with ratings) should get more current through to the tubes..
Okay then, i'll stick in a larger inductor, i'm using a small one as it fit the layout better but this thing is such a mess now anyway, who cares, i'll add a heat sync at some point anyway to the IRF, can't hurt.
Yeah the 12AU7 is hot like I can feel the heat coming off it but it's not getting burning hot, just wanted to max sure one tube wasn't over working or under working or something.
My Supply is lacking i'll admit, but it does seem to function okay for the moment at least, i'll upgrade it when I get something boxed up.
The oscillation is no longer an issue, it just didn't like the lower voltages, perfectly clean now.
I think it's time to move on to the next layout evolution of this one now! Seems to work well enough.
Ok, quick question.
I haven't built one yet, though I have a PCB layout for the Firefly i've not got all the parts.
Using a 12au7 as a PP power amp, how close does it sound to a pair of EL34's?
I know there are many variables involved, but it's something i'm interested in for my mini Plexi.
Quote from: Jaicen_solo on September 22, 2011, 08:50:12 AM
Using a 12au7 as a PP power amp, how close does it sound to a pair of EL34's?
nothing at all, but the same, the 12au7 will overdrive quicker but 99% of the people in the world will not know the diffrence
Errmm, ok. So the same, but not? ???
i dont think they sound very similar. Listen to some firefly clips and you will hear them. lil night train does to I think.
Quote from: Jaicen_solo on September 23, 2011, 02:56:55 AM
Errmm, ok. So the same, but not? ???
Since sound is perceived by the person hearing, people who know what a standard EL34 power-amp sounds like, will not ever think a 12au7 sounds the same.. But 99% of the people in the world do not care, it either sounds good or bad. Now I made the point of saying standard, because the sound is as much based on the design as it is the tube type. you can put an EL34 in triode mode and it will sound more like a 12au7.. It is claimed that the 12au7 sounds more like a power tube, but what does that mean? what is the bases for measuring that, except with our ear, where if someone said, this sound like that.. most people may agree, with out even knowing what X sounds like, or even side to side as they are expecting it.
Zambo has some examples, but I could not tell you by ear what tube he is using..
Hmm, I guess i'm looking for the general character and response, rather than a particular sound.
I'm currently running a SE EL84 amp, which has a great tone and response but it doesn't have that sound you get when you dig into something like a JTM45.
The PP thing i'm looking for is that 'chunk' sound when you dig in or palm mute. A SE seems a bit sweet, I just can't seem to get it to do that particular sound.
My leg still in plaster, but already able to walk somehow, so I moved home.
And couple of minutes ago I had 260V on my breadboard. Impressive. Just for a second - I didn't want to push it, but it seems that I am ready for putting the SMPS on vero.
Had a little stupid accident mistaking the big 330uF cap for the big 2,2uF/450v cap. Wondered why it didn't work, but found out the mistake before anything bad could happen.
Can't wait to try the amp then.
l_s
Quote from: lopsided on September 23, 2011, 12:53:03 PM
My leg still in plaster, but already able to walk somehow, so I moved home.
And couple of minutes ago I had 260V on my breadboard. Impressive. Just for a second - I didn't want to push it, but it seems that I am ready for putting the SMPS on vero.
Had a little stupid accident mistaking the big 330uF cap for the big 2,2uF/450v cap. Wondered why it didn't work, but found out the mistake before anything bad could happen.
Can't wait to try the amp then.
l_s
I found I got oscillation at low volumes with the 2.2uf and none with a 4.7uf
(http://dl.dropbox.com/u/14312589/IMG_20111009_121851.jpg)
My next Superfly.. Building for a Kid who plays.. These make great gifts..
I have an issue, I can not figure out. This is a single volume version, I have used this PCB in my other ones, so I know its good layout. I have replaced everything in the Power Supply but the Inductor and the 4.7 350V capacitor.
Symptoms..
If I run this at 120 volts all is good, just quite..
Runs at above 120V (I like the head room and volume of 180 volts) I get oscillation if I turn the volume up more than 1/4. I have tried putting a 500K resistor in series with the volume pot, but does not make a difference.
the only change is one the 6112 second stage where I used a 87K plate.
I am wondering if that plate resistor could be the problem.. or could it be the volume pot wiring?
I used my phone, I start @120v and then move up, I turn down the volume until there is no oscillation.
I am using the 3" speaker.. as my son moves the camera the sound changes.. that is not the issue :)
I've worked my way through this entire thread, noted all the changes to the original circuit and now I'm ready to start building. Just received my order of 7327 and 5840 tubes and parts for the nixie power supply. I'm not sure if I'm going to build this exact pedal but something along the booster/overdrive/preamp lines.
After checking several power supply circuits I'm still a little confused about what supply voltage is required. Most circuits say 9-12V but some I've seen go as low as 5V. I'd like to be able to use 6V so that it can power the filament of a single tube. Will that still work? Using 9 or12V and resistors to lower the filament supply voltage seems a bit of a waste.
I've found 6 and12VDC, 1A supplies readily available at Thrift stores for less than $5 each.
Now, just gotta make sure I keep the magic smoke in...
12V, you run the filaments in series.. so the 12v divides mostly evenly over each tube to 6 volts
the 5840 is not used in this design.. Two of 7327's would be used.
the SMPS is designed with 12v 1A in mind. Well not sure 1amp, but its what I figured is min.. :icon_mrgreen:
Plus this is a AMP not a Pedal, while it is possible to turn into a pedal, its not its design.
Finally came back to this project. The original schematic seems to be gone, can only find the version with the tone control. I want to make the tone control switchable. Can anyone confirm there is a 470K with 470p in parallel in place of the tone control - just like in the Firefly - in the original version?
Quote from: lopsided on February 16, 2012, 01:27:13 PM
Finally came back to this project. The original schematic seems to be gone, can only find the version with the tone control. I want to make the tone control switchable. Can anyone confirm there is a 470K with 470p in parallel in place of the tone control - just like in the Firefly - in the original version?
I still see it in the opening post.
Yes you are correct, however I removed the 470p on every 'non-tonestack' Fly I made, was getting some squeal and the removal solved it.
Quote from: frequencycentral on February 16, 2012, 01:50:01 PM
I still see it in the opening post.
And now I do to... Swear it did not load for me before...
Thanks for the quick answer, finally have all parts home, so I will give it a try.
One more quick question, if you don't mind:
Going through my stuff, I found that I screwed up a little and got myself a 125A20B reverb transformer instead of the 125A - problem is there is no center lug at the primary wiring.
I did a quick search and found out that some small amplifiers use this as OT and wire the output triodes in parallel: http://www.prowessamplifiers.com/schematics/misc/ThunderTweak_HeavyWatter-Thunder_Tweak_Heavy_Watter.html
Do you think is it worth giving a try to use the output section of this amp in the Superfly? Or is it a no-go for some reasons.
It is my first work with transformer, and as they are on the more expensive side I don't want to just hook them up and see smoke. So I rather ask...
I'm sure that's work out fine - good luck!
yep, I will give it a try.
found a good explanation of output stages topologies here:http://www.aikenamps.com/SingleEnded.htm
Excited to report I have just build my first (semi) functional tube amplifier.
It's actually a mixture of Rick's Superfly - uses the Superfly Special schematic with the accompanying nixie supply, Doug H.'s firefly - uses 12ax7 tubes, and the Thunder Tweak Heavy Watter - uses single ended output stage, because I have messed my order of the output transformer.
Why "semi" functional? I get pretty nice sound with maxed gain and mid volume, but when I lower the gain or rise volume I get some annoying whine, probably from the nixie, and sometimes unpleasant distortion kicks in. But in the working setting it sounds pretty good.
I have spent the whole afternoon building it, so I need a little break now, but will be back with a fuller report and possibly questions, if I will not be able to figure it by myself.
ok, so there is just one little question I would appreciate if Rick or somebody else could answer me:
Do you ground enclosures in the amp builds?
I think I remember reading somewhere that it should not be done, is it true and does it apply to these small projects too?
I originally did not ground it but then by experimentation found out, that if I do, most of my noise problems go away and the amp sounds good on most of the both pots rotation.
So, to ground or not to ground?
Ground.
Well I've been planing on making a superfly , for my first sub mini amp project. gonna make a standard one first from the superfly special layout(thanks Rick!). Now that the turkey day contest is over I can start working on this.
Early in the turkey day contest I seen some one making a pcb by hand drawing the traces and I thought I'd like to give it a try. I had some black pcb material on hand and a pcb marker so last night I gave it a shot.
Start process
(http://i1053.photobucket.com/albums/s479/MCMustachio/IMAG0234.jpg)
After etched and tinned
(http://i1053.photobucket.com/albums/s479/MCMustachio/IMAG0250.jpg)
Its not perfect but I'm happy with it I think it should work just fine :) I usually use the positive photo method to make boards but this was a lot of fun !
I think I have all the parts on hand now So gonna start building it this week!
Quote from: Mustachio on December 03, 2012, 08:00:32 PM
Well I've been planing on making a superfly , for my first sub mini amp project. gonna make a standard one first from the superfly special layout(thanks Rick!). Now that the turkey day contest is over I can start working on this.
Early in the turkey day contest I seen some one making a pcb by hand drawing the traces and I thought I'd like to give it a try. I had some black pcb material on hand and a pcb marker so last night I gave it a shot.
You do know there's a 1590A layout (http://rumbust.net/Superfly+in+a+1590A) for this one ;)
Hah yeah I seen your tinny 1590a build of this! Its pretty awesome! And I have a 1590a sitting here I haven't used. But I was planing on an orange squeezer for it as my first 1590a build. Doing a superfly in a 1590a for my first tinny box seems daunting but maybe in the future I have enough tubes to make 10 of these!
Been using your wiki for reference to this its great thanks for that!
Always nice to hear that someone uses it :)
Good luck and keep your fingers clear of the high voltage, it stings, trust me, I know.
I've had a lot to do lately and have had the board all soldered up. I realized it was flipped the wrong way when putting in components but I didnt think Id have problems untill I went to pop the ne555 into the socket haha all the pins would be wrong.
No biggie I figure I'll mount the IC and the tube sockets on the backside of the pcb and foam insulate the board so it doesn't touch the top of the box. gonna give it a try later tonight maybe if I have time. The other thing was the transistor couldnt be bent the right way since it was flipped but I just grabed a smaller heatsink off my valve caster and it fits fine now.
The only thing I have to look into is the wiring of the output of the transformer. I noticed everyone is using the center lugs top and bottom. I just gotta see how they connect to the output jack.
Either wire from the OT to either of the connections on the out jack. As it is a transformer they're isolated :)
For the 555 I believe you could have bent the pins "up" and flipped it on it's back and the pins would have been "correct", I sort of remember reading about others that done so on mirrored layouts. Haven't had to use that trick myself (yet) but it's a neat trick.
Edit: Stupid person using mobile app.
Nice Perrow! I didn't even think about bending the pins upwards on the IC I think ill do that. but the tubes will have to be mounted on the back which isnt a biggie I can do it. It might work out well for the way the board is mounted. Ill put foam on the bottom of the pcb and mount it to the inside top of the box and maybe it will help dampen vibration.
And for the OT's output , Thats what I was thinking but I haven't read much about the OT yet. So either of the 2 middle lugs to either of the tip/ring .
Thanks!
Yeah, tubes on the other side is a nice idea for this circuit. I've thought about building me another one and I might do just that. Though I think I'll draw a layout specially for that :)
I wired this up a few days ago and it worked right from the start! Was really happy to have it working. I need to widen a hole or 2 on my box to make things fit a lil better. I think I'm off about 1mm on my output jack and everything will fit perfect. So at the moment I have the board sitting outside the box. And its quiet no hum or noise from the power. I had it running at 185v no problem and took it up to 220v and still no problem just a little more volume and head room. I used a 7327 and a 6111WA .
It was a little dark/muddy with the 0.1 uf at C2 and C7 . So I took them out and put in sockets so I could test different values. When I did that something went wrong and I wasn't sure what. It stopped having any output but still good voltage to the plates so I knew power was fine but the audio path was bad. Double checked all my soldering and It was fine. Figured I would change tubes since I had 10 more on hand and bam instant working again! This time I used a 6112 in the pre. Sounded great with 0.022 uf at C2 and C7! Brought out all the articulation of my playing , The pickups in my main guitar are not very high output or tone so this value worked great for me. If anyone had a brighter sounding guitar I'd suggest the 0.033 uf in those spots.
One other thing I realized last night I used a 100K lin pot for gain instead of the 1m log. Gonna change that out maybe tonight or soon. I'm guessing this will give me more gain/output , It was just a mistake I grabbed the wrong pot. My only worry is that with the change I might end up hearing some noise at higher levels. Only one way to find out ;)
So far its a really cool sounding amp. I went with no tone stack because I usually find simple is best, and I figured Id just change the caps to fit my needs. I had a few 2x12 amps on the side that had the speakers wired so I tested it with them. With a fuzzface or tube screamer It really pushes it , can get some nice feedback. Even without the pedals it can feedback a little and even rattle a few hanging light fixtures haha!
Once I get it all fit in the box better and change the pot ill try to make a little demo video of it.
Ok so I got it going pretty good and I'm pretty much happy with it but ..... It is really missing the high end.
I have socketed C2 and C7. Originally .022uf in the firefly, I believe changed to 0.1uf in Ricks layout. I tried tons of caps - 0.1, 0.022, 0.0022 , 0.001
So yeah I went down to 1,000 pf and really not much of a difference at all ??? It did make it just a hair brighter.... I think.... But not anywhere near bright enough. I'm not expecting vox like high end shimmers but this just isn't cutting through for me. It sounds good on the bridge pickup But way to muddy in the neck or middle. I would prefer the tone I get from the bridge when I'm in the neck position and so forth down the line.
Any tips on brightening this up, Its really close just no cigar yet. Ill post a video of it soon.
Hi has the schematic gone AWOL or should I go to spec savers :icon_redface:
Please put me out of my misery and link me to the schematic, thanks.
Pelle has all the info put in one place here.
http://rumbust.net/Superfly
The first page has the original schem and page 7 has a schem with a tone stack
And page 9 has a pcb layout with changes
I found some info about cap selection switches for the firefly and noticed it all looks like what zvex does as well.
C2 and C7 are the ones to change in this layout
I believe at the moment I have 330pf in C7
And
0.022uf in C2
I have em socketed , but you could easily put them on a switch and alternate between 330pf and 220pf for C7
and 0.1uf and 0.022uf in C2.
And that seems like what the zvex has set up for its switches.
But the 330pf and 0.022uf work out best for me. It's not overly bassy any more has more high end bite and when you clean it up it makes things sound more clear.
I have mine running at 231v at the moment with these cap set ups and it will go from pretty clean to pure blues tube drive maxed out.
Dremeled out the top to give the tubes more room and make the mounting work better. Gotta file down a few spots, add the led, sand it and paint it next!
(http://i1053.photobucket.com/albums/s479/MCMustachio/IMAG0384_zps634329f4.jpg)
Can someone help me with a question about the wall wart.
I fried the inductor on my first try of this amp, I was using a 12v 1amp PSU and accidentally had the trim pot so it was trying to push max volts (and a tone pot wiring issue too).
Anyway, fixed the broken bits, sorted out the the trim pot and the tone control and fired it up again this morning with a 12v 400ma PSU and it works like a charm except for the issues of not having enough current.
Is there any reason I *cannot* use the 12v 1A PSU on this?
It's too much of a pain to pull apart if I fry any parts and it's the only other psu I have on hand.
Thanks in advance!
Koko
PS> at 160v and poor current it sounded very cool through a Vintage 12 and a C de-tuned guitar... ;D!
Hmm that's strange.
I'm using a 12v 1amp switching wall wart (PSU) and it works just fine. I've also taken it all the way to the top of the trim with no problems. Here's the model I'm using
http://www.digikey.com/product-detail/en/WSU120-1000-R/237-1456-ND/3094982
It's a switching PSU so there is a chance of heterodyne but I haven't had an issues.
I'm wondering if its your inductor's rating. Maybe post up some info on the power supply your using and the inductor so we can take a look at the data sheets.
I think each tube is going to want around 300ma
I know a few people had issues with popping inductors I'll take a look later for the inductor I used.
Thanks!
It very well could have been my bonehead wiring of the tone pot that caused the issue the first time.. just being gun shy 2nd time around since I remember the recommended PSU being 500ma somewhere in this thread.
The inductor is the same one that FrequencyCentral used, it's rated for 670ma
http://www.mouser.com/Search/ProductDetail.aspx?R=22R104Cvirtualkey58010000virtualkey580-22R104C
I'm also using FrequencyCentrals layout with an etched board.
The 1A psu is from a yamaha keyboard we have around the house.
Thanks again.
Is the yamaha keyboard psu your using out putting AC or DC ? center negative ?
The inductor should be ok ... maybe ... I think it depends on how much current the circuit will pull. And how much will be getting pulled through that inductor.
Now I'm not totally sure but I think just because the psu is rated at 1amp it will only feed the circuit what its trying to draw, up to 1amp and not just constantly push 1amp into the circuit.
I think the inductor I used was good up to 1.5 or 2amps.
DC, Center positive (but my hookup wiring takes that into account and the dc jack is the plastic type we normally use for pedals )
QuoteNow I'm not totally sure but I think just because the psu is rated at 1amp it will only feed the circuit what its trying to draw, up to 1amp and not just constantly push 1amp into the circuit.
This what I always thought too, didn't know if there was something special with this nixie circuit thought, sounds like not.
Ok, I'm feeling better that this may be ok since your using a 1a psu. I'll give it a try when I get home and report back with either a big smile or very sad face :)
It LIVES!!!
Thanks Mustachio!
(https://lh4.googleusercontent.com/-qcIrxB6QUDg/Uxe8iDmesbI/AAAAAAAAA2E/Gq7gdbVgx7o/w951-h536-no/2014-03-05)
Woot! Looks great! Congrats!
Another thing to keep in mind is , don't power it up without a speaker plugged in. Without load it can mess up the transformer. One trick is to use like a 2watt 8 ohm resistor with a stereo switched jack so when the cable is unplugged it has 8ohm resistance. I haven't done this myself yet but its a good idea just in case.
Nice Build! soundclips?
Has anybody tried a different approach for the output stage?
I saw this at http://www.dmitrynizh.com/submini-vibro-reverb.htm (http://www.dmitrynizh.com/submini-vibro-reverb.htm):
(http://www.dmitrynizh.com/6021-vibro-reverb-simple.gif)
Instead of grounding the second triode's grid, the grid is connected through a voltage divider to the first triode's plate.
I made a quick simulation using LTSpice and the result was an increase in volume.
With the extra resistors would it be possible to obtain more gain or headroom?
Thomas
QuoteAnother thing to keep in mind is , don't power it up without a speaker plugged in. Without load it can mess up the transformer. One trick is to use like a 2watt 8 ohm resistor with a stereo switched jack so when the cable is unplugged it has 8ohm resistance. I haven't done this myself yet but its a good idea just in case.
Yeah, I'll get that resistor on there when I add the LED.
What about a bypass switch? I added a pad to do but didnt hook it up but, I never see them on these sub-mini's (not even Zvex's looks like it has it). These little tubes are tough eh?
The max output is about the same or just slightly more as what I remember the ROG Ruby being, is that about right?
Hey Thomasha, back in oct of '12 Rick gave me that link and I read over it a bunch But never got around to trying it out.
http://www.diystompboxes.com/smfforum/index.php?topic=99454.0
Really good looking build and info there , It's still on my todo list.
I did record some sound clips of the superfly last year but never uploaded them. Maybe ill try to do a proper sound demo soon.
I'd love to see/hear some one do a submini amp with reverb and trem/vibe would be the bee'z knee'z .
Mustachio,
I built a Jcm inspired amp using the russian subminis and the Long-Tailed Pair phase inverter in the third schematic.
Unfortunately there is only simulation data available, would be interesting to see some build reports or something.
I tried Rick's Vibratone, but the murder one output stage was not enough for me, and the tremolo was not what I expected.
This superfly will be my next build, but I'm thinking of using the Max1771 SMPS since I already build 3 of them.
Is the 555 SMPS quiet? Or is there some switching noise at max. gain? And what about the brightness of the amp?
My murder one had a flabby bass, and only after reducing the first coupling capacitor to 2.2nF it was a little better.
Thomas
Its been awhile since i've posted here... I had previously built the full layout posted earlier in this site without success and having the Nixie PS and tube circuits on the same board proved to be too confusing for me to handle so I decided to try building the power supply by itself and then if that worked, continue to the tube stuff. After getting the power supply working I sort of lost interest.
I found my Superfly stuff in the garage last weekend and decided to give it another go. This time with better results. The power supply gives me between 100 and 190 volts DC. The amp plays and sounds good but oscillates badly if I turn up gain and volume past 3/10 or so.. I've tried searching this thread (and the Murder One) thread for posts concerning oscillation but have had limited results. Any ideas what might be making a circuit like this oscillate so badly?
A little bit of info.. My tubes are a 6112 and a 6021. I've build the Nixie and tube sections on separate boards. I've tried running it at everywhere between 100 and 190 volts with no change to the oscillation problem, just less headroom and volume. My AC adapter is a 12v regulated, 3A since thats all I had laying around. It gives me a solid 12.6v. I've tried swapping out the 555 ic and bc547 with no changes. I noticed that I accidently put the bc547 in backwards and there was no change either..
Any help would be awesome. Thanks in advance ;)
Sometimes when amps are not in sheilded boxes they can oscillate pretty bad. If you can find a way to sheild your amp circuit that may help ( i.e. puit it in a metal box ) it gets worse as the gain goes up.
I had some oscillation problem with the max1771,
the shielded box helped a lot, shielded wire too, but the supply layout is also very important.
Try using a small capacitor between feedback and ground, and between HV and ground, something like 100~200pF, that should remove the high frequency oscillation.
Before the amp B+ add a low value resistor in series and another capacitor, that will form a low pass filter.
Look at the layout, the signal should be far from the inductor, and if possible use a ground plane under the inductor. Depending on the type of inductor you will have more noise (radial) or more voltage drop and heat (toroidal), I don't know if my inductors are the bad type or what, but I experienced this issues.
(http://i210.photobucket.com/albums/bb292/frequencycentral/NixieSMPS.jpg)
can one of you blokes or blokettes using the circuit above tell me what frequency it runs at? is it high enough that you should be using a low ESR for the filter cap? and are you using a low esr? has anyone (yet) tried the circuit with both types, compared the results?
I used the layout on this site for the power supply. The title says 555 SMPS Layout by frequencycentral. It should be fine... I admit that the whole thing is sitting on my workbench with wires going everywhere but I can't imagine this is a normal level of oscillation. I can turn the volume to max but then the gain only gets to 2 or 3 out of 10 before it starts to oscillate badly. Same thing the other way around, if I max the gain I can only get the volume to 2 or 3 without problems.
I noticed that some of the cap values are different between the 555 SMPS layout i'm using, the Superfly layout and the actual Nixie schematic. It seems like theres a 330uf cap in the Nixie and Superfly layouts but that same cap in the 555 SMPS layout is a 100uf. It appears to be power supply filtering...? ??? I'll try changing that up to a 330 and hopefully it will help.
Hi Duck_arse, mine clocks at 48kHz approx. Actual frequency will depend on tolerance of the timer components.
Also frequency will change a little depending also on the voltage selected.
Tony
Hey Duck I checked my 4.7uf 350v cap I used on my superfly and it was a general purpose, Not a low ESR.
thanks, tony and mus. I don't know from, but in the app notes for the old 34063, which runs at similar speeds, they recommend low ESR caps. they show how the ESR affect the output ripple, and I quote from a worked example;
Quote
A 27 μF tantalum capacitor with an ESR of 0.10 Ω was again chosen. The ripple voltage due to the capacitance value is 28.7 mV and 44.2 mV due to
ESR. This yields a total ripple voltage of:
Eripple(p−p) = (Vout/Vref) 1.5 x 10−3 + (Iout/Co)ton + Ipk ESR
= 33.6 mV + 28.7 mV + 44.2 mV
= 107 mV
I say quote, I should say paraphrase.
Okay so I have the motor boat problem under control.. I ended up using another inductor which helped as well as a regulated power supply.
Now I have other issues.
I built a baxandall eq into it, between the gain control and the second triode. Its not working as it should. I used a push/pull pot for a tonestack bypass switch, wired as you would wire a dpdt switch to bypass an effects pedal. The input and output go to the middle lugs of the switch, one side is jumpered straight across (for bypass) and the other goes to the input and output of the tonestack. When I have the switch in tonestack mode the treble control works but the bass control works more like a reverse volume control. With it at 1 it gives me full signal and at 10 there is no volume at all. The volume and gain on the amp are what I would expect from a 1/2 watt amp when the bass is at 1. When I bypass the tonestack however the volume and gain drop dramatically. In bypass mode none of the tonestack controls work (as expected) but then the gain knob cuts out the signal after you turn it past 8 or so.
I have double checked layouts, solder points, etc. on the tonestack, preamp/power amp boards many times over and can't figure it out... I am getting 185vdc off the power supply..
Any ideas..?
could you draw a schematic of how you have it wired? sometimes its easier to see that way.
Okay. Got that sorted out. I found an incredibly small (still don't know how I saw it!) solder bridge between pin 1 of the 6112 and lug 3 of the gain pot. Now everything seems to be working fine. It has a fuzzier sound than i'm used to out of tubes but maybe thats got something to do with the pickups in my guitar as they're pretty high output (15-16k ohms) and this circuit seems like its probably suited for something lower output.
The baxandall is interesting.. You really have to pay attention to the sound rather than where the knobs are.
Apologize for the double post, though its probably not a big deal in a pseudo-dead thread anyway..
My superfly has been working for awhile now but was still giving me trouble with the fuzz/fart sound I mentioned in my last post. I swapped out the .02 coupling caps in the preamp section for some .01 and that seems to have fixed it. Now i'm getting a much more modern sound out of the amp and the fuzz is hardly there except at full gain with humbuckers. The overdrive sounds much more refined this way as well.
I noticed there was a bias mod for the second preamp triode.. I think i'll try that next..
on small amps I will use .0022uf and .022uf respectivley. somtimes taming the bass of the first section and letting it bloom on the second one work good. fwiw. Glad its working better :icon_smile:
So you're saying a .0022 on the first stage of the preamp and a .022 on the second?
Originally I had tried something like that, swapping the second stage cap for a .047 so I had .02 and .047 but this seemed to make the flabby farty bass sounds even worse so I started working back in the other direction. I tried reading around on how changing the values of these caps would work towards changing the sound but couldn't find a definitive answer like "change the values up for more bass, down for less"-type of thing. In the end I had to just go for it and start swapping out values. I tried a few combos.. .02/.047, .02/.027, .02/.02, but finally ended up with two .01uf.
I'd like to try some different values for cathode resistors as well. According to the book i've been reading this can have a dramatic effect on the sound. Unfortunately this was built on perf which isn't my cup of tea when it comes to trying out different values/tweaking. Maybe i'll solder a 5k pot in for each of the cathode resistors and see if theres a sweeter spot for each (to my ears anyhow!) and then just measure the pots and install fixed resistors that match.
hi,
i always use 0.0047uf as the first coupling capacitor and 820 ohms 0.680uf at first cathode.
A bigger cathode bypass cap makes the bass to mushy.
Another thing, after playing for 1 hour the sound changed a lot, and after some measurements I observed a voltage drop at the SMPS. Any ideia which component would be responsible for the SMPS efficiency loss after some heating? It's a 50 V voltage drop, and changes the volume and tone.
Quote from: MetalUpYerEye on March 30, 2014, 02:51:53 PM
So you're saying a .0022 on the first stage of the preamp and a .022 on the second?
Originally I had tried something like that, swapping the second stage cap for a .047 so I had .02 and .047 but this seemed to make the flabby farty bass sounds even worse so I started working back in the other direction. I tried reading around on how changing the values of these caps would work towards changing the sound but couldn't find a definitive answer like "change the values up for more bass, down for less"-type of thing. In the end I had to just go for it and start swapping out values. I tried a few combos.. .02/.047, .02/.027, .02/.02, but finally ended up with two .01uf.
I'd like to try some different values for cathode resistors as well. According to the book i've been reading this can have a dramatic effect on the sound. Unfortunately this was built on perf which isn't my cup of tea when it comes to trying out different values/tweaking. Maybe i'll solder a 5k pot in for each of the cathode resistors and see if theres a sweeter spot for each (to my ears anyhow!) and then just measure the pots and install fixed resistors that match.
Thats what i am saying . Bigger caps = more bass. Where you place the caps being most important. Amplify to much bass to soon you get farts. To much treble and you get ice pick to ears. we hear most sound in the mids so everyone scoops those. Balance seems tro be that your highs being more distorted ( not amplified ) and your lows being less distorted makes a more palatable tone to most people. So a small cap after first gain stage gets those highs on the way to clipping right away but leaves the bass out. the bigger cap after the second stage lets the bass through but its one gainstage behind the highs and less likley to clip as much in the power section in this scenario.
As far as bias goes, hot bias is ok but can lead to farty boomy bass as well. Judging by your name ( metal) you would probably like cold biasing more. makes more second harmonics pronounced in the sound. Thiink soldano , trainwreck Suhr etc. stages usualy go medium bias ( 1k5 ish ) or cooler biased ( 2k7 ish ) then cold biased ( 10k ish on up to 39k ) and are alternated to maintain balance. This has been my understanding of it anyway and ive read a bunch and built a fair amount. Merlin has a lot of cool stuff on his free web about it. I read there a lot. Its all personal taste and experimentation anyway but thought i would share for what its worth.
Awesome zambo!
I was wondering about the bias resistors and i've read some of Merlins book. A quick google search didn't seem to turn up any definitive answer (more resistance = colder bias, less resistance, hotter bias) like what you're saying.
I own a Blackstar HT5. Great little amp. I'd really like to get my Superfly somewhere close to that sound. Of course it wont have as much gain without the cascade stuff the HT5 has.
You're right about my name so i'll have to try cold biasing the tubes in my Superfly. Do you think a 25k pot is too much for testing?
no 25 or even 50 k as long as your testing. Probably should calc the voltage drop / ohms law thing and make sure your pot can handle the wattage. since you have to disconnect stuff i would just try a few resistors. try the knowns first and see what happens. 39k etc.. also hit the front of your amp with a clean boost and see what happens. usualy gets them screaming pretty good. beat that first gainstage with a boost and then limit the gain in the amp via the gain knob and magic stuff can happen.
Cool i'll have to give that a try!
I was wondering.. If I were to swap out my 6112 preamp tube for another 6021 could I rehash it to be single ended and use the first triode of the power tube as a preamp section for more gain? I got the idea looking at this schematic...
(http://www.jjs.at/electronic/class_a_subminiature_schematic_amp.gif)
If so, it seems like I would need a different output xfmr. Or could I use the 125a I have and omit the B+ tap?
Quote from: thomasha on March 30, 2014, 09:02:14 PM
Another thing, after playing for 1 hour the sound changed a lot, and after some measurements I observed a voltage drop at the SMPS. Any ideia which component would be responsible for the SMPS efficiency loss after some heating? It's a 50 V voltage drop, and changes the volume and tone.
50V is too much. you'll need to test for temperature, carefully. if your fingerprints stick to any parts, they are too hot. check your IC, inductor and mosfet, which you have, of course, on a generous heatsink. if something is getting hot, it might be affecting componets around it. maybe you got a bad regulator transistor. can we see pics of your board?
Quote from: MetalUpYerEye on April 01, 2014, 08:59:19 AM
Cool i'll have to give that a try!
I was wondering.. If I were to swap out my 6112 preamp tube for another 6021 could I rehash it to be single ended and use the first triode of the power tube as a preamp section for more gain? I got the idea looking at this schematic...
(http://www.jjs.at/electronic/class_a_subminiature_schematic_amp.gif)
If so, it seems like I would need a different output xfmr. Or could I use the 125a I have and omit the B+ tap?
There is a difference between se and pp transformers and i dont know if it would be fatal to the ot .Air gap and standing dc are terms i see a lot but dont understand so i wont pretend to. However.... if you went se and did the proposed plan you would get about half the volume your getting now as you will be missing half a tube. I would just put a boost in front because they are cheap and fun to build lol. A tube boost is even more fun. just pay attention to cap sizes and low pass/ high pass filters etc. Let your conscience be your guide. if your power supply is heating up and dropping volts i would hesitate to load it up any further.
zambo I haven't had any trouble with my power supply yet.. I remember reading somewhere in this thread that people were having problems with the irf740 heating up and heatsinking it and etc... I have run the crap out of mine and it doesn't even get warm to the touch. ;D
I'm really jonesing to meddle with the bias a bit but I took the amp over to my pops on poker night last weekend and it hasn't made it back.. Must sound ok huh! :D
I think my next project might be a full sized Firefly though i'm excited to try something with more volume. 5 watts seems to be about the standard for a first build tube amp with a power transformer, etc. so i'll probably go that route.
ax84 has some great 5 watts on the forum. lots of different ones. Its a great place to start. Firefly is good to , but you already have a low watt amp so yeah.. 5 is great. I have done plenty of gigs with a 5 watt se amp ! as long as your dealing with the voltage issues of a first build though, may as well spend a few extra bucks and build a single ended 10 watt with a6l6/ el34 . same build but louder. it keeps up with heavier drummers etc. worth a look anyway.
zambo i'm a CA state licensed electrician specializing in residential solar power. So I deal with split phase 240 volt AC (125-225 amp) and 350-550 volt DC (6-50+ amp) electrical systems every day. Highly trained in the art of safety, so thats slightly less of a problem for me than cost and volume requirement!
Still, it would be nice to have something louder than my HT5 to jam with friends, etc. Even cranked the HT5 is saying "cmon dude, we could use a little more!"
I'm just really taken with the Blackstar sound. If I can get somewhere near that with more volume (10-15 watts) without murdering my wallet then i'll be all set! :)
Ahh welll voltage is not an issue for you! I was ( and am ) slightly scared of it . much respect for the lightning juice! A single ended 6l6 is a loud beast. If its just about money and tone a push pull 6v6 amp is a beautiful thing. About 20 watts of lovin right there. the iron for that is cheaper too depending how you go. I use blues jr replacement iron and its cheap and effective. ends up around 18 watts and i am never too quiet. I dare say the se 6l6 is as loud somehow. they are just more in your face but not as "metal" sounding. anyway, good luck!
The HT5 does sound nice but it is mostly a solid state amp with some tubes in it,just listened and then looked at the schematic.Lots of non tube sound shaping going on in it,but it does have a nice Metal sound.The ISF is just a fancy sweep control using a dual ganged pot still kinda of cool and neat approach to an old idea.
If you are good with building pedals you could build the HT5 not sure how cost effective it would be once its boxed up though.
Probably cheaper to buy a used one and tweak it.
The HT5 is a great mix of tube and solid technologies. I'd never considered an HT5 pedal but that would really be pretty cool. The HT5 preamp is pretty extensive for a pedal though.. And I already have an HT5.. :-\
Would be great to get up to 15 or 18 watts with the HT5 preamp.. Guess I could build a preamp based off the HT5 and hack on a bigger power amp. ::)
or run the ht5 preamp out into a 20 watt tube power amp. It does have a preamp out right?
Oh yeah btw we totally hijacked this thread..
Hello!
Firstly thanks to Rick for this awesome project! I finally managed to finish this project(with 6021 + 6112 tubes). I made second one using russian variants of these tubes (according to seller's description), 6N16B-V + 6N17B-V, with respecting different pinout of these tubes.
Amp works, but it is ultra clean, no distortion even if Volume pot is at max(or both Volume and Master Volume pots). Rest of parts I used are same as shown on Rick's layout at page 9. Made it with Master Volume and Bias mod, no Tone Stack. Can anybody help me which parts to replace to get that nice crunch distortion as on samples? Thank you in advance!
Links to datasheet of both russian tubes:
1) 6N16B-V
http://www.goldenmiddle.com/files/6N16B.pdf (http://www.goldenmiddle.com/files/6N16B.pdf)
2) 6N17B-V
http://pdf.datasheetarchive.com/indexerfiles/Scans-026/ScansUX8555.pdf (http://pdf.datasheetarchive.com/indexerfiles/Scans-026/ScansUX8555.pdf)
Quote from: mrsmash23 on April 19, 2014, 11:12:38 AM
Hello!
Firstly thanks to Rick for this awesome project! I finally managed to finish this project(with 6021 + 6112 tubes). I made second one using russian variants of these tubes (according to seller's description), 6N16B-V + 6N17B-V, with respecting different pinout of these tubes.
Amp works, but it is ultra clean, no distortion even if Volume pot is at max(or both Volume and Master Volume pots). Rest of parts I used are same as shown on Rick's layout at page 9. Made it with Master Volume and Bias mod, no Tone Stack. Can anybody help me which parts to replace to get that nice crunch distortion as on samples? Thank you in advance!
Links to datasheet of both russian tubes:
1) 6N16B-V
http://www.goldenmiddle.com/files/6N16B.pdf (http://www.goldenmiddle.com/files/6N16B.pdf)
2) 6N17B-V
http://pdf.datasheetarchive.com/indexerfiles/Scans-026/ScansUX8555.pdf (http://pdf.datasheetarchive.com/indexerfiles/Scans-026/ScansUX8555.pdf)
That sounds really interesting! I stopped building Superfly to sell largely because sourcing significant batches of the tubes at a decent price is a hassle. Recently I've been thinking about doing exactly what you've done, as Russian tube seem more plentiful, and cheap too! I've been thinking of having some fabbed PCBs made up with on board pots to speed up the build time. Interesting that the Russian tubes are a cleaner sound...is it as loud as your 6021/6112 version?
Hello!
Subjectively they both sounds equally loud, but russian one without the crunch. First I made russian one with 2x 6N16B-V, than 6N16B-V + 6N17B-V and 2x6N17B-V. All combination and no crunch :-) Last combo felt louder, but sorry I have no numbers to back it up :)
I tried Mustachio's (Thanks M. for help you provided me!) suggestion about swapping some caps for different tone, but it has no effect on missing distortion. I guess it would take changing some resistors... Any advice from tube experienced folk would be appreciated! :)
Recently I made PCB sharing (99%)same layout with traces changed according to different pinout of russian tubes. I can send it to you in PM after I can safely confirm it is working.
Quote from: mrsmash23 on April 19, 2014, 01:08:39 PM
Recently I made PCB sharing (99%)same layout with traces changed according to different pinout of russian tubes. I can send it to you in PM after I can safely confirm it is working.
I'd love it please. Actually you should post it here for others to try too.
Quote from: frequencycentral on April 19, 2014, 01:14:04 PM
Quote from: mrsmash23 on April 19, 2014, 01:08:39 PM
Recently I made PCB sharing (99%)same layout with traces changed according to different pinout of russian tubes. I can send it to you in PM after I can safely confirm it is working.
I'd love it please. Actually you should post it here for others to try too.
+1
I have about 2 dozen russian sub mini tubes.I bought them cheap about 5 years ago to build some of Rick's stuff but never got around to it.
And have since forget what the pins are/lost the hand written english pin outs ,and I can't read the data sheet that was sent with them.
I would love to hear some sound clips of your Russian sub mini amp.
The Russian tubes I used had only two legs different from 6111/6112/6021, and they were next to each other so I just twisted those legs (insulated one of them) and used the standard layout.
BRYMUS:
can't A/B them simultaneously, got only 1 transformer at the moment I guess they're both similar only the missing distortion with russian tubes :(
I made "quick comparison guide" between western and eastern tubes and draw modified pcb, but not tested it at the moment. Please check it for errors by yourself before making it.
img5.rajce.idnes.cz/d0508/5/5681/5681993_a5168db5901a45267b327b0141ad31a4/images/SuperflyRU_guide.jpg (http://img5.rajce.idnes.cz/d0508/5/5681/5681993_a5168db5901a45267b327b0141ad31a4/images/SuperflyRU_guide.jpg)
PCB in PDF file:
http://www.sendspace.com/file/adie02 (http://www.sendspace.com/file/adie02)
Quote from: mrsmash23 on April 21, 2014, 06:04:58 PM
BRYMUS:
can't A/B them simultaneously, got only 1 transformer at the moment I guess they're both similar only the missing distortion with russian tubes :(
I made "quick comparison guide" between western and eastern tubes and draw modified pcb, but not tested it at the moment. Please check it for errors by yourself before making it.
img5.rajce.idnes.cz/d0508/5/5681/5681993_a5168db5901a45267b327b0141ad31a4/images/SuperflyRU_guide.jpg (http://img5.rajce.idnes.cz/d0508/5/5681/5681993_a5168db5901a45267b327b0141ad31a4/images/SuperflyRU_guide.jpg)
PCB in PDF file:
http://www.sendspace.com/file/adie02 (http://www.sendspace.com/file/adie02)
Wow !! Thank You 8)
That is a really awesome chart you made.IMHO it deserves it's own thread.
As far as getting more "crunch" from your Russian tubes Have you tried decreasing the plate resistors and increasing the cathode resistors.
Looking at a version of the "Superfly" w/o the cascode input,I would say raise the first cathode's R to something around 2K7 or higher,and lower the next stage's cathode R to 680R or 470R.While lowering both plate resistors to 47K.That should give it some nice crunch if those tubes behave anything like 12ax7 triodes.Which is what it looks like they are modeled after in the schematic.
(It's been a few years since I reviewed the sub mini stuff)
The russian version of SuperFly could become the BASS GUITAR outdoor jam tube amp!!!! Can anyone try it with bass? I was just looking for something cheap, tubey and CLEAN to use with my acoustic irish folk band, this could be my holy grail!
Hello guys!
I dismantled original superfly to get transformer, but now I can confirm that the modified PCB for russian tubes is working. Using sockets for tubes is amazing time saver!
BRYMUS: Thank you for your input! I tried to follow your advices of changing resistor, but not sure if I identified the resistors correctly:
"raise the first cathode's R to something around 2K7 or higher" -> R2 = 2,7k (from 1,8k)
"lower the next stage's cathode R to 680R or 470R" -> R3= 560R (from 820R)
"While lowering both plate resistors to 47K" -> R12, R13 = 50k (from 100k)
I did those changes, but still the amp got not crunch. I try higher value for R2 and lower one for R3 later...(in case I got confirmation I swapped right resistors :) )
(http://img5.rajce.idnes.cz/d0508/5/5681/5681993_a5168db5901a45267b327b0141ad31a4/images/SuperflyRU2.jpg)
GiulioGratz: I think you can give it a try. With russian tubes it is not expensive ( it works fine with 2x 6N16B-V ). As I mentioned with original parts your sound will be very clean even at high settings... Maybe also skip the BIAS mode, but use R17 value instead of R3 to be sure its "cleaner sounding than already clean" :)
Another thing I noticed, happens with both versions of amp, the voltage is slowly dropping after 10 mins of running by 8-10V (from 183V). Then it settles (jumping +/- 0.1V). If I turn it off for and on again (after a few seconds), voltage drop is still there. If I wait few minutes, the voltage is at original setting, 183V, and it is slowly dropping again...
I'm no tube expert... but all those mods sounds like they'd do the opposite of what you want and make it cleaner.
Edit: looking at the datasheet, it seems it has much lower gain than the 6112 too, 25 vs 70, you want the 6N17 in the preamp... or i'm just wrong :D
Quote from: Scruffie on April 22, 2014, 02:20:40 PM
I'm no tube expert... but all those mods sounds like they'd do the opposite of what you want and make it cleaner.
:icon_redface:
Yeah the Plate resistors need to be higher, I am very sorry I was very tired.
The plate resistors should be
INCREASED to something like 120-180K,as high as 220K,the higher the value the more gain the stage should have.
The lower cathode resistor biases the stage warmer,the higher cathode biases the stage colder.By biasing the stage out of its center area you get clipping much easier,especially when the gain is increased.(raising the plate R's)
By biasing the stages cold then hot a clean booster at the input can really make it sing.
One thing I read today to keep in mind, is to make sure you don't exceed the tubes dissipation.
The voltage drop may be from lowering the second stages cathode R as that value lowers you dissipate more.
Again I am sorry about the mis information on the plate resistors.
I would start by raising the input stages plate resistor to 180-220K ,with the original 1k8 cathode resistor set on a 10KL pot (so you can find your sweet spot) bypassed by a .68 - 1 uf cap.
The goal at the input is to get as much gain as possible to overdrive the second stage.
Then you can raise the second stage's plate R to get more gain too,but bias it hotter by lowering the cathode R (a 2-5KL pot should suffice to find best value)bypass the second stage cathode with around a 10uf cap.
Two stages are hard to get more than mild OD with, most 2 stage amps rely on the power stage for saturated distortion.
If you could add a cathode follower at the end of the pre amp feeding a tonestack/or not that would add some compression of the signal.
Not more gain but you would squash the signal/sine so as to cause distortion at the top and bottom of the voltage swing.
I should have asked what type of distortion you were after, :icon_redface:
Before giving my input and drafted a rough schematic to check my suggestion(lesson learned)
I will draw up what I am describing and post it so it is clear.
I think the second point I made is the most important, the preamp tube is more like an AU7 than AX7, if you can get the 6N17 there, that should get it back to sounding how it should with the standard values.
Lowering the plate resistors will also have increases current draw and perhaps the SMPS isn't liking that regards the voltage drop.
Thank you for helping me! I will try to adjust values of mentioned parts and hopefully find the sweet spot :)
Level of distortion -> I was going for similar (maybe a little bit higher) level as with 6112 + 6021 combo. First I used 2x lower gain 6N16B-V. Then I realized I need higher gain tube in preamp, but even with 6N17B-V in preamp section, amp is clean sounding with original parts. So to achieve similar level of cruch, I will need to experiment, I'll let you know!
Hello! I tried few combinations of resistor/caps as adviced. Finally, the crunch is here and feels similar to the one with 6112+6021 and original parts.
Parts I have changed with russian tubes:
------
R2: 1,5k
R3: 470r
R12: 220k
R13: 120k
C1: 1uF electrolytic
---
Although it is not the only possible combination. Crunch is present with R2=1,8k (but under 1,5k amp started to squeel), R3=560r, R12=180k and R13=100k. I tried these values as 2nd try, for the 3rd try I tried to go higher(/lower) with values to see if the crunch gets any higher, but I guess the sound didn't get dirtier...
BRYMUS: "If you could add a cathode follower at the end of the pre amp feeding a tonestack/or not that would add some compression of the signal." If you have time and mood to draw your suggestion, I'd like to try it! (You can find schematics with tone stack on page 7).
OT: Sorry, can't see EDIT button...
I am glad that worked for you! :)
Did you use pots on the cathodes to find the best values or did you swap resistors?
(the idea for using pots comes from Merlin's book on building valve pre amps)
http://www.valvewizard.co.uk/ (http://www.valvewizard.co.uk/)
Here is some very good info about the type of CF I am talking about.
http://www.valvewizard.co.uk/dccf.html (http://www.valvewizard.co.uk/dccf.html)
Yes I will draw a schematic - it will have to be hand drawn though,not as pretty as the chart you made. :icon_redface:
I will also post the data sheet of the Russian tubes I have,maybe you can help me decide what they best cross reference to?
(I believe they are sub mini pentodes,IDK it's been awhile since I even looked at them)
Here is what I am talking about,since you need another double triode you might as well use the other half and parallel the input stage for less noise and more dynamics.
I love the sound of a two parallel triodes with separate cathode resistors.
IDK if the tonestack will sound the same,I usually use a TMB tonestack,you would still get compression from the CF even if it just fed the output stage.
Or with an extra double triode you could have an extra gain stage too,a lot of possibilities. A bit more work and more current draw,more chance of added noise,ect.
Since getting Merlin's book I am going to mod the stuffing out of my last build which was a Marshall Plexi Super Lead.
Anyway:
http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=50866&g2_serialNumber=1 (http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=50866&g2_serialNumber=1)
Here is the data sheet from the sub mini tubes I bought a few years back,I can't even remember what they were called :icon_rolleyes:
There must of been a reason I bought them though,I know for a sub mini tube amp,but thats it.
I do recall they were from MIG fighter plane controls thats it.
If anyone can translate these I would be very happy!!!
(http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=50869&g2_serialNumber=2)
(http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=50873&g2_serialNumber=2)
I remember someone else used them to make a fuzz circuit for his hammond organ,so they should be usable...
Quote from: Brymus on April 24, 2014, 09:11:54 PM
If anyone can translate these I would be very happy!!!
(http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=50869&g2_serialNumber=2)
(http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=50873&g2_serialNumber=2)
I remember someone else used them to make a fuzz circuit for his hammond organ,so they should be usable...
It's easy - 1ZH29B-V, high frequency pentode, second picture is datasheet, first line is heater voltage when cathodes are in series and in parallel - 2.4 and 1.2 V, then comes heater current - 56-68 mA if cathodes are in parallel, then plate voltage - 60V, plate current 3.6-7 mA, first grid voltage - need a bigger picture, first greed back (or how it is in English?) current- 0.3 mA, second grid voltage - 45 V, second grid current - not exceed 0,5 mA. These are normal exploitation conditions, below there are list of parameters for extreme functioning mode.
Thank You here are links to the full size images:
http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=50871&g2_serialNumber=1 (http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=50871&g2_serialNumber=1)
and
http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=50867&g2_serialNumber=1 (http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=50867&g2_serialNumber=1)
I would really like to know as much about them as possible.
Thank You,
Bryan
Quote from: Brymus on April 25, 2014, 03:43:17 AM
Thank You here are links to the full size images:
http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=50871&g2_serialNumber=1 (http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=50871&g2_serialNumber=1)
and
http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=50867&g2_serialNumber=1 (http://www.aronnelson.com/gallery/main.php?g2_view=core.DownloadItem&g2_itemId=50867&g2_serialNumber=1)
I would really like to know as much about them as possible.
Thank You,
Bryan
Ok, I see. So let's continue! Second grid voltage is 0 V. Line "Крутизна характеристики" is S, for 1zh29b it is equal to 1.7-3.3, durability is 5000 hours minimum, 90% exhaust - not less than 7500 hours, closer to exhaust S decreases.
So called 'extreme' parameters are:
1. Uplate 150 V max
2. Ug2 120 Vmax
3. Icathode 8 mA max
4. P diss pl 1.2 W max
5. P diss g2 0.35 W max
6. R g1 1Mohm max
The tube is so called 'nuvistor' and designed to be implemented in space rockets, satellites etc.
P.S.: There are also 'true' submini tubes, they are close analogues to full-size tubes, contrary to nuvistors, which are designed to work with lower voltages etc. True subminies are marked as 6xxNNБ, where 6 is heater voltage, letters after it is a tube type (N or Н in Russian is for twin triode, С is for single triode, P or П is for power pentode, ZH or Ж is for high ferquency pentode etc), then comes modification number, and finally a letter which points at a tube form-factor (in case of subminies the letter is Б or B in English - submini)
AWESOME!!
Thank You ZAP that really helps,as does your info on how to decipher the tube designators.
I want to try the 6N17B-V that MR Mash used a few posts back,
I believe I bought these to use as a Push Pull output stage for a sub mini amp,(since they are pentodes)
Not sure I want to push them at "extreme" tolerances though.
Even 150 plate voltage is low,so maybe somewhere between the recomended 60V and the extreme of 150V.
Really! thank you for taking the time to translate that for me,I very much appreciate your help! :)
Enjoy, my friend, I am glad to help.
Actually, if you are intended to build submini version of a big amp the best choice for that is 6n17b as it can easily replace 12ax7 and 6p30b which is a some kind of hybrid between EL84 and 6V6, closer to 6V6 maybe. Nuvistors are not the best choice in my opinion. Some guys here, in Russia, where I am from, tried to build nuvistor amp, but were not completely satisfied with a result. There are some contras they say, such as final sound which differs from traditional tube sound. Anyway, if you are intersted in nuvistor based stuff, you can visit this thread of our local forum: http://forum.gtlab.net/cgi-bin/yabb2/YaBB.pl?num=1249507367
I know the thread concerns nuvistor based stompboxes, not amps, but the information is interesting. Some guys know English a bit, they can explain something if there will be questions. Or punch me, I'll try to help.
a slight diersion .....
Quote from: Brymus on April 24, 2014, 09:11:54 PM
I do recall they were from MIG fighter plane controls thats it.
before the age of the mojo wires (so it MUST be true), I heard tell, I don't know where, that when the "west" got their hands on a late model russian front-line fighter, they were astonished to find it full of valves. turns out they are radiation harder (more harden?) than semicondutors in the event of an EMP.
carry on.
Quote from: duck_arse on April 25, 2014, 10:48:09 AM
a slight diersion .....
Quote from: Brymus on April 24, 2014, 09:11:54 PM
I do recall they were from MIG fighter plane controls thats it.
before the age of the mojo wires (so it MUST be true), I heard tell, I don't know where, that when the "west" got their hands on a late model russian front-line fighter, they were astonished to find it full of valves. turns out they are radiation harder (more harden?) than semicondutors in the event of an EMP.
carry on.
That is almost correct, it was 1976 when our fighter-pilot highjacked MiG-25, the newest soviet fighter jet of that time. I am not shure about astinishment of 'west' specialists when they saw tubes inside that plane, but the truth is that most important electronic parts of plane, including radar, were tube based. I think it was a measure of need, because of lack of good semiconductors. The tubes, like Brymus has (I mean 1zh29b), were designed to fill this lack (Am I saying right? Not shure it is grammatically correct). And it is also true that tubes are more durable under EMP.
the saying is fine, the spelling a little wonky, nothing we can't manage.
I've since been thinking about my source of this story, it was a fellow I knew when 18-ish. he told me a lot of stuff; 75% was his imagination and the other 40% was just wrong. it's affected my thinking ever since.
Well, your fellow wasn't mistaking much, the story is at least 90% reliable, except 'astonisment' I think. MiG-25 was a perfect machine, a true masterpiece of that time, I don't wonder if it impressed western military experts with its technical solutions and stuff.
Hello @all,
I am going to order my parts but I have two questions:
IRF740 - there are some differrent types of the IRF740 available, for what specs should I look after?
Can the 18N50-Mosfet be used (less heat should be very interesting ;) ) - again, what specs?
Would be nice to know a bit about them before odering something worse ;)
Greetings from Germany
Magnus
Hello Magnus,
IRF740 - I ordered those from 2 sources, both work fine, Im posting links to their datasheets in case you use different store (hope those links aren't considered as banned advertising):
http://www.taydaelectronics.com/datasheets/A-086.pdf (http://www.taydaelectronics.com/datasheets/A-086.pdf)
http://www.futurlec.com/Transistors/IRF740.shtml (http://www.futurlec.com/Transistors/IRF740.shtml)
Hello,
thank you - thats usefull :)
Greetings
Magnus
Hi Magnus
I think the 18N50 was the one I used and it worked perfectly, lot less heat. Watch out for the pinout, I think it's different. There are other versions of IRF mosfets that have better specs (lower rds on). I think the 740 was selected just because it was cheaper than other models.
Good luck building this.
Thank you, Perrow :)
I will buy both, the IRF740 and the 18N50 and make a test because I am curious ;)
Greetings
Magnus
Hello,
while I'm waiting for the SMPS IC for my firefly build I would like to show some pictures of the building process, hope you like it!
the circuit is the firefly with tone and master volume using russian submini tubes and the max1771 smps. Inspired by Perrow I tried a 1590a build. I'm still in the testing stage, until now everything fits in the box. I'm going to put a 2mm plastic sheet between the the enclosure and the copper layer to avoid accidents.
(http://i1303.photobucket.com/albums/ag159/Thomas_Eduardt_Hafemann/IMG_20140425_205112_zps51aeb776.jpg)
(http://i1303.photobucket.com/albums/ag159/Thomas_Eduardt_Hafemann/IMG_20140506_204354_zps9e8d68cc.jpg)
(http://i1303.photobucket.com/albums/ag159/Thomas_Eduardt_Hafemann/IMG_20140506_2044461_zps2c19cfd6.jpg)
(http://i1303.photobucket.com/albums/ag159/Thomas_Eduardt_Hafemann/IMG_20140506_204126_zpsce5ffc51.jpg)
(http://i1303.photobucket.com/albums/ag159/Thomas_Eduardt_Hafemann/IMG_20140506_203809_zpse6504f1a.jpg)
Cheers
Thomas
Looking real nice there, see you even went for the same labeling solution :icon_mrgreen:
How hot will that mosfet get?
Are you willing to show your layout?
Hi Perrow,
your build was really awesome, and I looked for similar solutions, as you can see :icon_biggrin:
When the build is finished and I'm sure everything is working I will post the schematic and layout, but I'm still waiting for some components.
I hope the mosfet will stay cool. As I'm using the max1771, instead of the 555, the mosfet is already way cooler.
I'm testing which would be the best option between irf840, irf740 and irf644. The irf644 is only for 250V, but it has a resistance of 0R28, and is way more cooler than the others, and was the first mosfet used by Nick de Smith.
Thomas
Hello,
what about the 440 Ohm-resistor, seems that this value doesn't exist :-\
Will 470 Ohms be ok for the circuit?
Greetings
Magnus
Quote from: Magnus on May 10, 2014, 02:05:04 PM
what about the 440 Ohm-resistor, seems that this value doesn't exist :-\
Will 470 Ohms be ok for the circuit?
440R does exist. Or you can fudge the value with resistors in series or parallel. Or just use 470R, it'll be fine.
Hey Magnus,
I used a 1k2 with the 6N16B russian submini.
Finished my amp today, take a look! I used Max1771 SMPS instead of the 555, and the IRF644 fet. The low ESR capacitor REALLY makes the difference with this SMPS, I tried a normal 10uF and had a lot of strange noises. After the changing it for a 4.7uF low ESR for pc power supply it was way better.
(http://i1303.photobucket.com/albums/ag159/Thomas_Eduardt_Hafemann/IMG_20140510_171916_zps7eedb3e3.jpg)
(http://i1303.photobucket.com/albums/ag159/Thomas_Eduardt_Hafemann/IMG_20140510_182647_zpsb41f93e7.jpg)
I still want to add a perforated metal sheet protection, like the lil night train (that's why the color). I used same knobs as Perrow's, they really fit nice in such a small build.
Now his amp has a dark side brother :icon_lol:
After I finish the schematic with the last changes I will upload the layout, if anyone is interested! And a sample, as I always ask for sound samples ...
Thank you Frequency Central for such a nice amp, and Perrow for the awesome idea and tutorial!
Cheers
Thomas
Congratulations on a really nice build, looks like there's more room to move around in yours than in mine :icon_mrgreen:
Next step will be to move the transformer and tubes inside the enclosure :icon_eek:
Spectacular build! Mind sharing more about it, layout, schematic?
Thank you guys! I'm really happy with the sound of this amp!
I made a PDF file with layout, and schematic, the link is:
https://dl.dropboxusercontent.com/u/10420127/Superfly%20Project.pdf (https://dl.dropboxusercontent.com/u/10420127/Superfly%20Project.pdf)
The PCB board is already scaled (that's why it's a pdf file...)
Tomorrow I will make a sound sample, if possible.
Greetings,
Thomas
Hello,
@Rick:
Thank you ;)
The wallwart is the same as for the Murder One?
@Thomasha:
Wow, this is really awesome - great work 8)
Greetings
Magnus
THOMASA:
Amazing work! I was thinking about using the max1771 circuit for Superfly too, you were faster :)
Can I ask you:
- Which brand and series of low ESR caps did you use? Not sure what ESR value is enough for this application.
- R17: 0.1 Ohm / 2W -> Is 2W resistor necessary (I have some 1W of same value)?
- Do you think that transformer you used, Schatz TS 3.60.A, is better match for russian tubes than hammond 125A?
If you think it would be better -> Is there any european dealer for those? Except for their official brazilian web I can't find any additional info.
Hi mrsmash23,
I would suggest that for the SMPS you take a look at this:
desmith.net/NMdS/Electronics/NixiePSU.html (http://desmith.net/NMdS/Electronics/NixiePSU.html)
I used the capacitor that was available, it's for PC power supply, it's a Rubycon, I guess if you can buy from Mouser or digikey, there will be something hundred times better for the same price, like the PANASONIC-ECG.
For the resistor 1W will be fine, I only find the 2W here.
For the transformer, I couldn't find the 125A, and this one I bought is a little bigger (5 mm in every direction), that's why one of the screws is at the left side of the box.
Stay with the 125A or equivalent with 22.5k PP. I know there is the OT5PP and Ampmaker also has one 4W for the 12au7 and ECC99.
And now, the sound sample! Sorry for my bad playing skills...
Cheers, Thomas
Hi everybody!
My submini-mania strikes again. Do you think it would be easy to convert circuit to russian subminis?
Mini Amp 2.0 by FcKw inspired by Trainwreck / Vox Night Train.
Preamp with 3 gain stages + phase inverter = 2x ECC83 -> 2x 6n17b-v
Power amp ECC99 with gain of 22 -> 6n16b-v (gain 25-30) or 6n18b-v (gain 18-28) with Hammond 125A as OT
As high voltage power supply: FC's max1771 circuit which should have enough current to run it.
Do you think this conversion as mentioned would be possible without any significant changes?
Bonus question: Do you think I will still have enough current to add magic eye, EM80? Using regulated 12V@2A supply which should be enough.
Schematics:
http://diyguitarfreak.files.wordpress.com/2010/09/miniamp2-schematic1.jpg (http://diyguitarfreak.files.wordpress.com/2010/09/miniamp2-schematic1.jpg)
Tubes overview:
http://i.imgur.com/OfLQO1j.jpg (http://i.imgur.com/OfLQO1j.jpg)
Hi!
nice to see that this thread is still not dead!
Let's see,
my suggestion is: build the amp using the mini amp values and tweak them to sound as you like, I did that with my submini JCM.
To avoid problems with the output stage use the superfly's cathode resistor value, or 1.2k as used by
http://www.dmitrynizh.com/submini-vibro-reverb.htm (http://www.dmitrynizh.com/submini-vibro-reverb.htm)
The available current with the max1771 is enough, maybe you only need to change the resistor and inductor. My experience says, use 0.05R for more than 25mA and 0.1R for less than that. A bigger inductor will allow more current, a 2A or 3A will be fine, http://www.desmith.net/NMdS/Electronics/NixiePSU.html (http://www.desmith.net/NMdS/Electronics/NixiePSU.html) explains it all. The IRF644 is better than the IRF840, because it has less internal resistance. Don't forget to put a heat sink on it, it get's a little hot when running 4 tubes.
I see you want to run only 3 tubes, but to use 12V with the heaters you will need 4 tubes, or 3 tubes and a resistor: 400+-40 mA 6V will require at least a 3W resistor with 13.6R, 14R is the nearest value I could find, it will dissipate 2.57 W, so a 3W should be Ok. I had done it with my Russian Murder one, but using the regular 18 ohms 2W resistor and a higher value resistor in parallel, but I only had a low wattage one, so the first time it went to hot and almost unsoldered itself.
Assuming that the magic eye consumes 300mA you can use a lower wattage resistor in parallel to dissipate 60 to 140mA. Considering the highest current the resistor would dissipate: P=VI=6*0.14=0.88W and would have a resistance of: R=V/I=6/0.14=42.85R. So, instead of using the bigger wattage resistor alone you could use your magic eye and a smaller resistor to dissipate the same current as one 6N16B or 6N17B for example.
The heater's max. current is: 2x440mA =880mA (2 tubes in series in parallel with the remaining tube, magic eye and resistor). I also use a 12v 2A supply with 4 submini and 1 SMPS and it works.
Another approach would be use the magic eye alone with a resistor, and the bigger wattage resistor in series with the signal tube, but it would require an extra 300mA current.
Now the heater's current would be 880+300=1180mA. Don't forget that you also need current for the SMPS, in this configuration ideally you still have aprox. 9.8VA available. Considering the max1771 efficiency it's enough to obtain the 235V you need with a decent current.
If you need, I can help you, just ask if you have any question. take a look at my Amp here:
http://www.diystompboxes.com/smfforum/index.php?topic=79544.msg942552#msg942552 (http://www.diystompboxes.com/smfforum/index.php?topic=79544.msg942552#msg942552)
Cheers
Thomas
Finally got the materials to build this! (:
Couple of questions came up. How hot are the 6111WA tube supposed to get. Mine seem to get pretty hot. They are hot enough to touch but can't keep my finger on the tubes for more than 4-5 seconds.
The other question I have is the pre-amp section is working because I can connect it up direct to my amp and get sound but the power amp section gets nothing.
I'm thinking it may be the transformer but I'm using this one:
https://www.tubesandmore.com/products/P-TF22921
I've wired up the power amp section two ways, using the Sub Zero which uses the 6111 tubes and the Firefly which uses the 6111WA.
Any assistance will be greatly appreciated.
-Byron
That transformer is single ended. It won't work with the Superfly's self split push/pull arrangement as there is no centre tap. You could modify the output section to work, but best get a Hammond 125a. Just building a Superfly myself today.
Thx FC for the response and assistance!
Yes, I suspected that the xformer may be the problem. BTW, Is it normal for the tube to get pretty hot?
Just the preamp section sounds pretty nice straight into a solid state amp. (;
-Byron
Yes they should be almost too hot to touch. :-)
Good luck with your build.
Quote from: frequencycentral on December 01, 2014, 05:36:12 PM
Yes they should be almost too hot to touch. :-)
Good luck with your build.
Hey Thx FC!
Where are you ordering the transformers from? I just ordered one from Mouser w/ shipping cost me around $40 bucks.
UK: http://www.bluebellaudio.com/
EU: http://www.musikding.de/navi.php?suchausdruck=hammond+125a&JTLSHOP=7ab467bfc69c4cf0a850f1aba0e3f97c
If needs be, I'm happy to answer questions about the MAX1771 design - I'm the author of the one referenced in this thread - many 100s have now been built, lots for audio use...
The Hammond 125A xformer came in! Wired it up w/ the center tap to B+ and it works.. awesome BUT the tube glows on pin 1 kind of bright.
The glowing goes down when I have the gain turned all the way up and I'm playing thru it. When I stop playing the glowing comes back.
Is this normal?
(http://i648.photobucket.com/albums/uu208/bk-vegas/M1400023_zps4a7273b2.jpg)
Thanks!
Byron
Check your wiring and tube pinouts. Tubes should glow steadily.
Thanks FC!
I couldn't get the tube to glow right w/ the Sub Zero power amp wiring so used Doug Hammond's Fire Fly power amp w/ your Sub Zero preamp section and was able to get relatively loud output w/ normal glowing tubes. So I have a hybrid of both amp designs using only 6111WA tubes. It sounds really good w/ and w/out Tube Screamer in front of it! I'll share the schematic as soon as I'm done doing some tweaks to the circuit. If anyone is interested, let me know and I can post some sound clips.
Again Thanks FC!
Hi,
I was looking for some SMPS ideas using the MAX1771 and found this:
http://lucythesoloist.blog33.fc2.com/blog-category-64.html (http://lucythesoloist.blog33.fc2.com/blog-category-64.html)
instead of using a 4.7uF electrolytic capacitor, they use two 2.2uF film capacitors... and it has two output power stages running in SE...
As I'm out of low ESR high voltage electrolytic capacitors, is there a problem using 400V film capacitors instead?
Nick, have you tried using high voltage film capacitors? Are they an improvement over regular electrolytic capacitors?
Thomas
Hello,
I am working on my Superfly and I have two questions:
1) The tube-pinout is as shown on my grafic right?
(http://abload.de/img/tube-pinoutxfoeg.jpg)
2) The voltage - do I have to adjust it with or without tubes installed?
Greetings from Germany
Magnus
Hi Magnus,
1) Tube pinout is OK
2) With tubes installed, with load the voltage will decrease. The best setting is the lowest noise setting.
How are your submini projetcs?
Cheers,
Thomas
Hello,
thank you, Thomas :)
I have to finish the layout for the submini-jcm, but first I will build the Superfly ;)
Greetings
Magnus
Hello,
I have two last questions:
My inductor (Murata) has two different long legs - does it have a polarity? (I don't think so)
Where do I have to measure the voltage at using the trimpot?
Greetings
Magnus
Hi Magnus,
I don't think the inductor has a polarity, I never considered it in my builds.
The voltage you measure between ground and high voltage, in orange on the layout.
The trimpot works as a feedback resistor reducing the output voltage.
Thomas
No polarity on the inductor.
And keep your fingers away when measuring the voltage, or whenever your board is powered for that sake. I soldered an extra wire from the high voltage so I could crocodile clip the DMM to it. That way I didn't need to handle the board when powered, plus I got visual confirmation that the voltage went down after powering down and before handling it.
Thank you, thomasha and Perrow 8)
Greetings
Magnus
Hi guys.
I've been reading the 1st 5 pages of this thread and have decided I want to make the Superfly. I'm a newbie but have successfully built 5 fx pedals including Bajamans tube distortion pedal before but still have plenty to learn. I am not very good at reading schematics at this stage but, I CAN work it out if I can see the pcb and work backwards. (but there's so much I don't know)
However, I think this is the perfect next project for me
I have a few questions. Is the pcb layout on the 1st few pages the layout I should use or has there been an update I don't know about??
When buying the Nixie power supply kit which one should I buy as there are different kits for different applications. Valve Radio, Valve clocks etc??
As I understand it, the pcb that's shown on Page 2 of this thread shows the power supply on the board right? Then there is discussion about how it shouldn't be on the same board because of noise or hum. What is the thinking on this now?? Should I go ahead as it is on page 2 or ??
I'm sure there will be more questions but just those two for now thanks!
ps I'm a much better muso than I am an electronics builder, repairer, guy thingy
I'd read the whole thread before you order parts... There's at least three schematics available! It depends on what tubes you can find and what size enclosure you're going to stuff it into. There's a Russian tube version, the original version that uses a handmade SMPS, and a version that uses a MAX chip for a simpler SMPS. I was actually thinking of buying a prebuilt SMT Nixie power tube supply off ebay (Something like this: http://www.ebay.com/itm/171374739771) to simplify the build.
On a side note, thanks to everyone "I'm going down the rabbit hole" - Liam (on building tube stuff).
Quote from: frequencycentral on December 01, 2014, 04:14:39 AM
That transformer is single ended. It won't work with the Superfly's self split push/pull arrangement as there is no centre tap. You could modify the output section to work, but best get a Hammond 125a. Just building a Superfly myself today.
How would I go about modifying the output section to make this work with with a single ended transformer? I only have a hammond 1750a. I just wired 1 & 8 together on tube 6111 for now. I got sound but not loud. Thanks.
Hello,
just two questions about the output-transformer-connection:
Hammond 125A:
Pin 5 to output-jack-ground (is it grounded with the input-jack- and circuit-ground too?)
Pin 2 to output-jack-tip
Greetings
Magnus
Is there a kind soul out there who could share with me how to tie the gain and tone controls from the Superfly Special schematic into either the above pcb layout or the perf layout?
I have tried working it out for myself but i keep ending up thinking that some of the connections to the tubes differ between the layouts and the schematics. I am not good at circuit design but i follow instructions well :)
any assistance would be greatly appreciated
Gary
Hi, guys, I need some help debugging my build. Spent a lot of time on this thread, read all of the little hints and suggestions but still don't have a working amp. I'm using the PCB layout, with added Tone, Bias, and MV controls.
When I plugged in my power supply (center positive but I wired appropriately) and flipped the power switch, my LED lit up, and I immediately got 12V at the center tap. The tubes' heaters began to glow, and I figured in a couple of seconds I'd see the voltage start to climb. Then, nothing. LED goes off, voltage drops. No smoke, crackles, sizzles, pops.
I went over everything I could think of, including checking the tracing for solder bridges or other shorts in the wiring. I think the tube polarity is correct (gap towards the NE555, right?). The VR was a little bent after getting it to fit, so I replaced that: no change. I also swapped out the BC547 transistor (I had socketed per FC's suggestion) as well as the NE555 without any change. When adding the tonestack, I omitted both R16 and C8. I didn't bridge the gap left by the absence of C8 (reading the updated schematic, none of the remaining connections went to ground), I figured trying that without a filter cap would only potentially fry more components.
What would be the other potential culprit components to check? I've built a few pedals and tube amplifiers so this isn't completely new to me, however problem solving beyond the simple stuff is over my head.
Thanks for any ideas!
https://dl.dropboxusercontent.com/u/23281298/IMG_3827.jpg (https://dl.dropboxusercontent.com/u/23281298/IMG_3827.jpg)
https://dl.dropboxusercontent.com/u/23281298/IMG_3830.jpg (https://dl.dropboxusercontent.com/u/23281298/IMG_3830.jpg)
https://dl.dropboxusercontent.com/u/23281298/IMG_3828.jpg (https://dl.dropboxusercontent.com/u/23281298/IMG_3828.jpg)
(Sorry, I had originally included the pics in my post, but they were massive and I wasn't sure how to resize them in dropbox...)
Hey guys. I'm in the process of ordering parts to build the Superfly and I just had a small question: What are those sockets the tubes go into called? The ones normally used for 8-pin ICs.
Thanks in advance!
This should be the upper limit on pricing:
http://dhost.info/mhdtlab/socket.htm
eBay also lists 8-pin submin sockets. They are used in the Eico HFT-90 FM tuner and HFT-92 AM/FM tuners to hold the 1M3 tuning eye tube and in a number of European radios for similar tubes. On rare occasions you may find them in surplus stores.
...or $0.12...
http://www.taydaelectronics.com/8-pin-dip-ic-socket-machine-tooled.html
...or make your own, expensive at $0.39...
http://www.taydaelectronics.com/30-pin-dip-sip-ic-sockets-adaptor-solder-type.html
Hey I was just wondering where the input jack and output jacks grounds go in the circuit. I have some experience with electronics but not much.
Thanks!
Hi all. What kind of power supply should I get for this project? I know it has to be 12 volts, but how many amps?
All the ground points in the circuit connect together, along with the ground lugs on the input and output jacks. Rick says on page 1 that he was using a 500mA power supply (but a few pages on he's using 750mA).
Thanks for the help!
All image links are now dead, I would appreciate if someone can post original schematic again, and even better schematic for amp with glowing tubes. :(
(https://i.imgur.com/VfPnHdI.png)
(https://i.imgur.com/il5Th1f.jpg)
Nice, thanks!
Added the Nixie power supply for you too. (Hope Rick doesn't mind me re-posting this stuff.)
I had that supply, but thanks anyway! What is B+ voltage for this little amp?
Rick doesn't mind at all, and is hoping to get the time to host some of his Photobucket/Dropbox lost content on his website someday soon. He's even working on a new phaser PCB for you.
Sorry to bump an old question, but looking to finally get this little amp working (having another kid definitely put a big freeze on my trouble shooting!).
Any suggestions are welcome. I'm to the point where I may just pull everything salvageable and try to build it on project board rather than trying to etch another ghetto home-brew PCB.
Cheers.Quote from: Scheissami on February 16, 2017, 04:48:15 PM
Hi, guys, I need some help debugging my build. Spent a lot of time on this thread, read all of the little hints and suggestions but still don't have a working amp. I'm using the PCB layout, with added Tone, Bias, and MV controls.
When I plugged in my power supply (center positive but I wired appropriately) and flipped the power switch, my LED lit up, and I immediately got 12V at the center tap. The tubes' heaters began to glow, and I figured in a couple of seconds I'd see the voltage start to climb. Then, nothing. LED goes off, voltage drops. No smoke, crackles, sizzles, pops.
I went over everything I could think of, including checking the tracing for solder bridges or other shorts in the wiring. I think the tube polarity is correct (gap towards the NE555, right?). The VR was a little bent after getting it to fit, so I replaced that: no change. I also swapped out the BC547 transistor (I had socketed per FC's suggestion) as well as the NE555 without any change. When adding the tonestack, I omitted both R16 and C8. I didn't bridge the gap left by the absence of C8 (reading the updated schematic, none of the remaining connections went to ground), I figured trying that without a filter cap would only potentially fry more components.
What would be the other potential culprit components to check? I've built a few pedals and tube amplifiers so this isn't completely new to me, however problem solving beyond the simple stuff is over my head.
Thanks for any ideas!
https://www.dropbox.com/s/9iv6es4ydmxf5v0/IMG_3827.jpg?dl=0 (https://www.dropbox.com/s/9iv6es4ydmxf5v0/IMG_3827.jpg?dl=0)
https://www.dropbox.com/s/bivgp8l4l7ups1w/IMG_3830.jpg?dl=0 (https://www.dropbox.com/s/bivgp8l4l7ups1w/IMG_3830.jpg?dl=0)
https://www.dropbox.com/s/r2vjbmdru9a0k6l/IMG_3828.jpg?dl=0 (https://www.dropbox.com/s/r2vjbmdru9a0k6l/IMG_3828.jpg?dl=0)
(Sorry, I had originally included the pics in my post, but they were massive and I wasn't sure how to resize them in dropbox...)
Quote from: frequencycentral on November 14, 2017, 07:19:20 PM
Rick doesn't mind at all, and is hoping to get the time to host some of his Photobucket/Dropbox lost content on his website someday soon. He's even working on a new phaser PCB for you.
That would be very cool, Rick. Like a fridge with shades on. :icon_cool:
Quote from: Scheissami on November 15, 2017, 02:34:30 AM
Sorry to bump an old question, but looking to finally get this little amp working (having another kid definitely put a big freeze on my trouble shooting!).
Any suggestions are welcome. I'm to the point where I may just pull everything salvageable and try to build it on project board rather than trying to etch another ghetto home-brew PCB.
Cheers.
Quote from: Scheissami on February 16, 2017, 04:48:15 PM
Hi, guys, I need some help debugging my build. Spent a lot of time on this thread, read all of the little hints and suggestions but still don't have a working amp. I'm using the PCB layout, with added Tone, Bias, and MV controls.
When I plugged in my power supply (center positive but I wired appropriately) and flipped the power switch, my LED lit up, and I immediately got 12V at the center tap. The tubes' heaters began to glow, and I figured in a couple of seconds I'd see the voltage start to climb. Then, nothing. LED goes off, voltage drops. No smoke, crackles, sizzles, pops.
I went over everything I could think of, including checking the tracing for solder bridges or other shorts in the wiring. I think the tube polarity is correct (gap towards the NE555, right?). The VR was a little bent after getting it to fit, so I replaced that: no change. I also swapped out the BC547 transistor (I had socketed per FC's suggestion) as well as the NE555 without any change. When adding the tonestack, I omitted both R16 and C8. I didn't bridge the gap left by the absence of C8 (reading the updated schematic, none of the remaining connections went to ground), I figured trying that without a filter cap would only potentially fry more components.
What would be the other potential culprit components to check? I've built a few pedals and tube amplifiers so this isn't completely new to me, however problem solving beyond the simple stuff is over my head.
Thanks for any ideas!
https://www.dropbox.com/s/9iv6es4ydmxf5v0/IMG_3827.jpg?dl=0 (https://www.dropbox.com/s/9iv6es4ydmxf5v0/IMG_3827.jpg?dl=0)
https://www.dropbox.com/s/bivgp8l4l7ups1w/IMG_3830.jpg?dl=0 (https://www.dropbox.com/s/bivgp8l4l7ups1w/IMG_3830.jpg?dl=0)
https://www.dropbox.com/s/r2vjbmdru9a0k6l/IMG_3828.jpg?dl=0 (https://www.dropbox.com/s/r2vjbmdru9a0k6l/IMG_3828.jpg?dl=0)
(Sorry, I had originally included the pics in my post, but they were massive and I wasn't sure how to resize them in dropbox...)
You must find out where is the first point without power. So, power this up, take DMM and measure voltage from DC plug to NE555 and forward.
Okay, so based on the description the problem is most likely to be a problem with the power supply so focus my problem solving on the SMPS system, yes? This is my first time building this particular circuit so not sure what the most likely culprit components are, but I suspect I'm looking for a complete inability to pass voltage forward? Not sure if I understand enough about the circuit to know which parts of the circuit will be carrying what voltage.
It'll probably be a few days before I'll have a chance to sit down and test the circuit, I'll respond with my findings.
Thanks for your input!
You may try to disconnect tubes and see is there any power in the circuit or not.
Does anybody have these images? Photobucket fix isn't working here.
https://www.diystompboxes.com/smfforum/index.php?topic=78302.msg704930#msg704930
That's the one I have:
(https://s26.postimg.cc/idtkhyw89/Superfly.png)
I have that one too. The one I'm looking for is the one with tone, master volume and bias mods.
I have this one>
(https://s31.postimg.cc/er0m7mrk7/Superfly_Specialapril10.png) (https://postimg.cc/image/er0m7mrk7/)
The bias mode is here>
(https://s31.postimg.cc/r5ne83o93/New_Superfly_PCB.gif) (https://postimg.cc/image/r5ne83o93/)
That's exactly what I was looking for! Thanks, Thomas.
Question on that 440r cathode resistor. How important is to use this value? I mean, what's the difference if I use a 390r or 470r instead?
Perhaps not too important, but you can use two 220R in series. ;)
Ok, so I'm almost ready to test my Superfly. Just need to solder the pots. I just have two more questions (that may be answered in this topic, but I'm still didn't finished to read all the posts):
1- What's the output power of the Superfly? The version without a tone pot.
2- I'll use the enclosure as the heatsink for the IRF740. Do I need to isolate the IRF metal tab from the enclosure?
Quote from: Marcos - Munky on June 22, 2018, 11:20:53 PM
1- What's the output power of the Superfly? The version without a tone pot.
2- I'll use the enclosure as the heatsink for the IRF740. Do I need to isolate the IRF metal tab from the enclosure?
I don't recall any power output being mentioned, other than it being "wife-worryingly loud". :icon_wink:
My datasheet doesn't show how the tab is connected, but it would be easy enough to find out with a DMM. If it's the source, then I guess it would be fine (the schematic shows it's connected to ground). I'd be inclined just to insulate the tab regardless.
The datasheet I used doesn'tshow the tab connection too, I just checked and it's connected to the drain. So, it needs to be insulated. Bad news, since the next store that sells electronic stuff is about 25km away from home, but I should be near the store this week.
As for the power, it's really not mentioned and I didn't found this info on google. I asked because the original Firefly transformer is a 3.5W one (oversized). To keed the size down, I ordered a 1W transformer. Since the max plate dissipation is 1W, the output should be lower than 1W.
Quote from: thomasha on May 10, 2014, 09:04:54 PM
Thank you guys! I'm really happy with the sound of this amp!
I made a PDF file with layout, and schematic, the link is:
https://dl.dropboxusercontent.com/u/10420127/Superfly%20Project.pdf (https://dl.dropboxusercontent.com/u/10420127/Superfly%20Project.pdf)
The PCB board is already scaled (that's why it's a pdf file...)
Tomorrow I will make a sound sample, if possible.
Greetings,
Thomas
Thank you guys for sharing all these beautiful mini amps, I would like to have a look at the pdf file but the link is broken, could someone please post it again or send to by pm. I would appreciate it. Thanks
I've built the original Superfly, everything looks good and all connections are properly soldered but for some reason when I turn on the power the tubes won't even light up. Has anyone else had this issue?
Are your tubes known to be good? Do you have 6V across each heater? (Pins 3-6.)
The tubes are good, I even swapped them out for extras I got(just in case) I also used my multimeter to see if the power is actually getting to the amp and nothing.
Quote from: jma38 on April 02, 2022, 01:35:12 PM
...everything looks good and all connections are properly soldered...
Clearly not!
You need to trace where your 12V enters your board and find out where it stops. Can you post photos? More eyes might help.
Quote from: frequencycentral on April 03, 2022, 04:06:44 AM
Quote from: jma38 on April 02, 2022, 01:35:12 PM
...everything looks good and all connections are properly soldered...
Clearly not!
True now that you mention it
Quote from: bluebunny on April 03, 2022, 05:42:55 AM
You need to trace where your 12V enters your board and find out where it stops. Can you post photos? More eyes might help.
(https://i.postimg.cc/LqnxGJNy/superfly-back.jpg) (https://postimg.cc/LqnxGJNy)
Here's a picture of the soldered board. I'm realizing I'm definitely not as adept at soldering as Rick(the soldering on the back of those first Superfly prototypes was downright beautiful).
Quote from: jma38 on April 03, 2022, 11:37:59 AM
Quote from: frequencycentral on April 03, 2022, 04:06:44 AM
Quote from: jma38 on April 02, 2022, 01:35:12 PM
...everything looks good and all connections are properly soldered...
Clearly not!
True now that you mention it
Sorry if that seemed harsh! I spend a lot of time helping people debug. The absolute worst starting position is "I've done everything right and it doesn't work". First step of debugging is to own not having done everything right. Second step is to find out what dumb thing you did. 😀
Quote from: frequencycentral on April 03, 2022, 05:30:01 PM
Quote from: jma38 on April 03, 2022, 11:37:59 AM
Quote from: frequencycentral on April 03, 2022, 04:06:44 AM
Quote from: jma38 on April 02, 2022, 01:35:12 PM
...everything looks good and all connections are properly soldered...
Clearly not!
True now that you mention it
Sorry if that seemed harsh! I spend a lot of time helping people debug. The absolute worst starting position is "I've done everything right and it doesn't work". First step of debugging is to own not having done everything right. Second step is to find out what dumb thing you did. 😀
Oh no problem, I didn't interpret that as harsh :) and yes it's true, the first step to finding the problem is admitting that something wasn't done properly. I enjoy this DIY stuff so much I'm not even frustrated going in to debugging the board.
Just to eliminate a possible power supply issue I've ordered a new 12v 500ma power supply. It should be here in about a week.
Have you measured the power supply as requested earlier?
Quote from: bluebunny on April 04, 2022, 04:42:38 PM
Have you measured the power supply as requested earlier?
Yes, my meter was reading absolutely nothing.
Quote from: jma38 on April 04, 2022, 05:19:44 PM
Yes, my meter was reading absolutely nothing.
Your meter might need power supply, also.. :icon_wink:
More seriously, what do you mean with "nothing"..??
Quote from: antonis on April 04, 2022, 05:31:32 PM
Quote from: jma38 on April 04, 2022, 05:19:44 PM
Yes, my meter was reading absolutely nothing.
Your meter might need power supply, also.. :icon_wink:
More seriously, what do you mean with "nothing"..??
:icon_lol: It isn't reading a voltage at the power input of the amp. Nowhere on any other part of the circuit either.
Quote from: jma38 on April 04, 2022, 06:06:05 PM
Quote from: antonis on April 04, 2022, 05:31:32 PM
Quote from: jma38 on April 04, 2022, 05:19:44 PM
Yes, my meter was reading absolutely nothing.
Your meter might need power supply, also.. :icon_wink:
More seriously, what do you mean with "nothing"..??
:icon_lol: It isn't reading a voltage at the power input of the amp. Nowhere on any other part of the circuit either.
'Nothing' is a metaphysical term, as this is science that we're doing, we're dealing in scientific terms. ie what is the voltage? 0V?
0 volts
Did you take PS measurement out of circuit or connected to it..??
First - have you tested your power supply like this ? :
(http://www.ladyada.net/images/metertutorial/maswart.jpg)
Second - what sort of power jack are you using ?
Is it a plastic center negative standard power jack like this ? :
(https://www.pcboard.ca/image/cache/catalog/products/components/2mmx5mm_dc_power_jack_plastic-800x800.jpg)
And if so....have you tested it with no wires attached to it like this ? :
(https://www.diyaudiocircuits.com/wp-content/uploads/2013/03/dc-jack-test-connect-terminals-open-circuits.jpg)
If yes - to all of these - are you sure you have the proper positive/negative connections to the board configured correctly ?
Dan
My easiest troubleshoot ever--and biggest 'Doh!' moment, was when my dead new pedal turned out to have the polarity protection diode in backwards. No juice, no sound! Easy to spot: if there's 9v north of the diode, but not in the circuit past that point... Luckily I hadn't plugged the wrong power supply into it, or I would have had to fix a lot more than just flipping around a 1N5817.
Quote from: antonis on April 06, 2022, 06:58:58 AM
Did you take PS measurement out of circuit or connected to it..??
So it turns out the power supply I was using is dead and is just heating up when it's plugged in. I'm waiting on the new one I ordered and I'll give an update after I test with the new one.
New 12 volt, 500 ma power supply came yesterday. I tested it with my meter and it definitely has an output of 12 volts as advertised. I've been using my multimeter to look at voltages on the board and I'm still getting 0 volts when I test the voltage input of the amp. Could this be a sign that somewhere on the board there's a connection that hasn't been made?
Quote from: Ben N on April 07, 2022, 04:05:16 PM
My easiest troubleshoot ever--and biggest 'Doh!' moment, was when my dead new pedal turned out to have the polarity protection diode in backwards. No juice, no sound! Easy to spot: if there's 9v north of the diode, but not in the circuit past that point... Luckily I hadn't plugged the wrong power supply into it, or I would have had to fix a lot more than just flipping around a 1N5817.
I tested that area but still reading 0v. Thanks for the suggestion though.
Quote from: antonis on April 06, 2022, 06:58:58 AM
Did you take PS measurement out of circuit or connected to it..??
With the circuit connected to the power supply.
Quote from: danielzink on April 07, 2022, 01:57:39 PM
First - have you tested your power supply like this ? :
(http://www.ladyada.net/images/metertutorial/maswart.jpg)
Second - what sort of power jack are you using ?
Is it a plastic center negative standard power jack like this ? :
(https://www.pcboard.ca/image/cache/catalog/products/components/2mmx5mm_dc_power_jack_plastic-800x800.jpg)
I'm using this one: https://www.taydaelectronics.com/dc-power-jack-2-1mm-x-5-5-mm-round-type-panel-mount-dc-099.html
And if so....have you tested it with no wires attached to it like this ? :
(https://www.diyaudiocircuits.com/wp-content/uploads/2013/03/dc-jack-test-connect-terminals-open-circuits.jpg)
I've tested that and I'm getting 0v coming from the female DC connector. Looks like that has something to do with it. I'm not sure what that problem is though.
If yes - to all of these - are you sure you have the proper positive/negative connections to the board configured correctly ?
Dan
I'm getting a reading of 12v when testing the female DC connector connected to power and nothing else but when I test it connected to the amps power input wires I get 0v.
Quote from: Ben N on April 07, 2022, 04:05:16 PM
My easiest troubleshoot ever--and biggest 'Doh!' moment, was when my dead new pedal turned out to have the polarity protection diode in backwards. No juice, no sound! Easy to spot: if there's 9v north of the diode, but not in the circuit past that point... Luckily I hadn't plugged the wrong power supply into it, or I would have had to fix a lot more than just flipping around a 1N5817.
I thought this was the right way around to put the rectifier, did I get it backwards?
(https://i.postimg.cc/Sj5QGD7v/superflyrecifier.jpg) (https://postimg.cc/Sj5QGD7v)
What part of the circuit is that? From time to time it's good to repost whatever schematic you're working from if you can. Just saying cuz I dropped in and am not sure where you're at based on the page 1 info...
Quote from: jma38 on April 28, 2022, 03:21:22 PM
Quote from: Ben N on April 07, 2022, 04:05:16 PM
My easiest troubleshoot ever--and biggest 'Doh!' moment, was when my dead new pedal turned out to have the polarity protection diode in backwards. No juice, no sound! Easy to spot: if there's 9v north of the diode, but not in the circuit past that point... Luckily I hadn't plugged the wrong power supply into it, or I would have had to fix a lot more than just flipping around a 1N5817.
I thought this was the right way around to put the rectifier, did I get it backwards?
(https://i.postimg.cc/Sj5QGD7v/superflyrecifier.jpg) (https://postimg.cc/Sj5QGD7v)
I can't look at the schematic right now, and I can't really tell from the pic, but it depends if you have the protection diode wired in series with the circuit or across the power supply. The banded end is the cathode = (-). If it's in series, you want the diode to conduct when you feed it +V, so the unbanded side goes towards the +9v supply. If it's wired between +9v and ground, then normally you don't want it to conduct--you only want it to conduct if the polarity of the power supply is reversed--so the banded side goes to +9v and the unbanded side goes to ground.
I'd remove it til I got the thing working, personally...I put that in just about last in builds. If it's got semiconductors, I put them in after verifying correct polarity, before applying power to them...
If the right side of the diode is connected to "+" and the banded side (cathode) to ground, then it's in wrong in terms of protection diode.
As I see the picture, diode faces to electro cap negative leg..
(an almost short..)
That kind of diode is rated at 1A continous current so a 500mA PS can do no harm to it..
(of course, its output voltage goes deeply down..)
Just lift one diode leg (whichever you like) and repeat measurement.. :icon_wink:
Quote from: GibsonGM on April 28, 2022, 05:17:35 PM
I'd remove it til I got the thing working, personally...I put that in just about last in builds. If it's got semiconductors, I put them in after verifying correct polarity, before applying power to them...
If the right side of the diode is connected to "+" and the banded side (cathode) to ground, then it's in wrong in terms of protection diode.
It looks that way judging by the pictures of the original build Rick did: (http://i210.photobucket.com/albums/bb292/frequencycentral/100_0111.jpg)
The schematic is on page one of this thread, the layout is on page 2. Here's the layout: (http://i210.photobucket.com/albums/bb292/frequencycentral/Superflyperf.gif)
The diode pictured is (well, should be) a UF4004, and is part of the SMPS which generates the HV. Looks to be the right way around.
^^ Yep, that diagram nailed it - it's the PS, not a protection diode. Also, that diode NEEDS to be a UF4004 or similar 'fast' diode in order to work. Sorry if you have already covered this ground...I don't believe a typical Si rectifier diode will do the job. It's easiest to make this kind of circuit by building the power supply and testing it, then assembling the valve stuff, just my opinion.
Be aware that is the high voltage switch supply, which can put out 'potentially lethal voltage' within the circuit and at its output... :icon_eek: No fingers in there, buddy.
Quote from: jma38 on April 28, 2022, 01:27:22 PM
Quote from: danielzink on April 07, 2022, 01:57:39 PM
Second - what sort of power jack are you using ?
Is it a plastic center negative standard power jack like this ? :
(https://www.pcboard.ca/image/cache/catalog/products/components/2mmx5mm_dc_power_jack_plastic-800x800.jpg)
I'm using this one: https://www.taydaelectronics.com/dc-power-jack-2-1mm-x-5-5-mm-round-type-panel-mount-dc-099.html
interested parties that noticed that comment and link would find this at the other end ....
(https://www.taydaelectronics.com/media/catalog/product/cache/3727e7324aff0beca75a17e6d9fba59e/A/-/A-5245-2.JPG)
which, as we all know, is a metal DC jack. metal DC jacks short to the case, which will usually short your power supply, if fitted to a metal box. is your jack fitted to a metal box, along with the in/out jacks? if so, you need to isolate the body of the DC jack from the metalwork, or get a plastic jack.
Is it possible to use some kind of PT for output? For example, 220V / 6V ct? Or it needs CT on primary side of PT?
Quote from: duck_arse on April 29, 2022, 10:20:08 AM
Quote from: jma38 on April 28, 2022, 01:27:22 PM
Quote from: danielzink on April 07, 2022, 01:57:39 PM
Second - what sort of power jack are you using ?
Is it a plastic center negative standard power jack like this ? :
(https://www.pcboard.ca/image/cache/catalog/products/components/2mmx5mm_dc_power_jack_plastic-800x800.jpg)
I'm using this one: https://www.taydaelectronics.com/dc-power-jack-2-1mm-x-5-5-mm-round-type-panel-mount-dc-099.html
interested parties that noticed that comment and link would find this at the other end ....
(https://www.taydaelectronics.com/media/catalog/product/cache/3727e7324aff0beca75a17e6d9fba59e/A/-/A-5245-2.JPG)
which, as we all know, is a metal DC jack. metal DC jacks short to the case, which will usually short your power supply, if fitted to a metal box. is your jack fitted to a metal box, along with the in/out jacks? if so, you need to isolate the body of the DC jack from the metalwork, or get a plastic jack.
Can I ask where you got the plastic jacks in those pictures on your last post?
Quote from: GibsonGM on April 29, 2022, 07:27:57 AM
^^ Yep, that diagram nailed it - it's the PS, not a protection diode. Also, that diode NEEDS to be a UF4004 or similar 'fast' diode in order to work. Sorry if you have already covered this ground...I don't believe a typical Si rectifier diode will do the job. It's easiest to make this kind of circuit by building the power supply and testing it, then assembling the valve stuff, just my opinion.
Be aware that is the high voltage switch supply, which can put out 'potentially lethal voltage' within the circuit and at its output... :icon_eek: No fingers in there, buddy.
I can confirm the diode is a UF4004. and thanks for the warning, I definitely don't want to be shocked by something that high voltage.
Quote from: jma38 on April 28, 2022, 07:05:45 PM
The schematic is on page one of this thread, the layout is on page 2. Here's the layout: (http://i210.photobucket.com/albums/bb292/frequencycentral/Superflyperf.gif)
Ok, so...the diode seems ok. Where you want to use your meter to look for DC volts is at the bottom of C3..and pin 4 of the 555 timer chip (IC1). Let's determine if you have power there. That blue line at the bottom is your 'power rail' for 12V, and ground is the next rail above it.
Quote from: GibsonGM on April 29, 2022, 12:39:26 PM
Quote from: jma38 on April 28, 2022, 07:05:45 PM
The schematic is on page one of this thread, the layout is on page 2. Here's the layout:
Ok, so...the diode seems ok. Where you want to use your meter to look for DC volts is at the bottom of C3..and pin 4 of the 555 timer chip (IC1). Let's determine if you have power there. That blue line at the bottom is your 'power rail' for 12V, and ground is the next rail above it.
Just tested, at first I get 0v but then I get an intermittent reading of 0.1v, like every few seconds that's the reading I get.
Have you tried checking if there is a short between 12V and ground, without the supply?
And check if you have continuity between jack and board. Just to check that the wires are correctly soldered. Happens with everybody.
If that does not work, it is time to check the circuit by areas. You can unsolder the trace that goes to the 555, to cut the 12V connection and check the if you have 12V at the tubes. For this test, you can even measure it with the tubes disconnected. We just want to know if there is a problem with the tubes or with the 555. If the first section of the tubes is OK, you can add the tubes and see if they light up. If it still works, the problem is with the SMPS. If not, you have bad tubes.
To check the tubes, measure the resistance of the heaters. It should be very low, but higher than 1 to 4R. If you have a low resistance at the filaments, the tube is shorted and you will have to fin another one. Normally they do not fail that way, but who knows.
Which kind of supply are you using? Does it have any kind of protection? I had some good supplies which would shut off when shorted. In some cases the heaters of the tubes look like a short. In your case, I think it will be OK because they are in series.
If it works with the tubes, but not with the SMPS, try disconnecting stuff from the 555, if it's possible. Ideally you would test if the 555 is working, without the mosfet and diode. Just to see if there is something wrong with this part of the circuit. If the 555 is socketed, you can remove it and measure if you get 12V without it (bad 555) or if it is still at 0V.
You can check if the Mosfet (IRF740) is good by measuring the resistance between pins. It should be around 740R, if I am not mistaken. A shorted mosfet is the most common problem with the SMPS I build, you just need to short the HV line and gnd and it kills the mosfet and the 555.
Good luck! This is a really nice amplifier.
PS.: I checked your board, and there are some suspicious points...the schematic was mirrored to be easier to compare. Check at the points with red circles, if there is a short between traces.
I would suggest that you use less solder, or if you can, remove some of it. The large blobs do not help, most of the time, when it looks like a nice sphere, you have actually a bad joint.
(https://i.postimg.cc/tscdMPBC/Untitled.png) (https://postimg.cc/tscdMPBC)
Quote from: jma38 on April 29, 2022, 01:02:47 PM
Just tested, at first I get 0v but then I get an intermittent reading of 0.1v, like every few seconds that's the reading I get.
That periodic reading sounds like a power supply trying to protect itself (for example, against a short), and repeatedly checking if the fault has gone away.
No continuity between jack and connection to the board. I'll be touching up the connection with solder after I'm done work. It might not be the only problem with my build but this seems to be the main problem. Thanks for the suggestions, I'll be doing the other tests after work.
Quote from: thomasha on April 29, 2022, 02:10:08 PM
Have you tried checking if there is a short between 12V and ground, without the supply?
And check if you have continuity between jack and board. Just to check that the wires are correctly soldered. Happens with everybody.
If that does not work, it is time to check the circuit by areas. You can unsolder the trace that goes to the 555, to cut the 12V connection and check the if you have 12V at the tubes. For this test, you can even measure it with the tubes disconnected. We just want to know if there is a problem with the tubes or with the 555. If the first section of the tubes is OK, you can add the tubes and see if they light up. If it still works, the problem is with the SMPS. If not, you have bad tubes.
To check the tubes, measure the resistance of the heaters. It should be very low, but higher than 1 to 4R. If you have a low resistance at the filaments, the tube is shorted and you will have to fin another one. Normally they do not fail that way, but who knows.
Which kind of supply are you using? Does it have any kind of protection? I had some good supplies which would shut off when shorted. In some cases the heaters of the tubes look like a short. In your case, I think it will be OK because they are in series.
If it works with the tubes, but not with the SMPS, try disconnecting stuff from the 555, if it's possible. Ideally you would test if the 555 is working, without the mosfet and diode. Just to see if there is something wrong with this part of the circuit. If the 555 is socketed, you can remove it and measure if you get 12V without it (bad 555) or if it is still at 0V.
You can check if the Mosfet (IRF740) is good by measuring the resistance between pins. It should be around 740R, if I am not mistaken. A shorted mosfet is the most common problem with the SMPS I build, you just need to short the HV line and gnd and it kills the mosfet and the 555.
Good luck! This is a really nice amplifier.
PS.: I checked your board, and there are some suspicious points...the schematic was mirrored to be easier to compare. Check at the points with red circles, if there is a short between traces.
I would suggest that you use less solder, or if you can, remove some of it. The large blobs do not help, most of the time, when it looks like a nice sphere, you have actually a bad joint.
(https://i.postimg.cc/tscdMPBC/Untitled.png) (https://postimg.cc/tscdMPBC)
Thanks a lot for taking the time to mark those soldering points. I'll fix those soon.
Quote from: thomasha on April 29, 2022, 02:10:08 PM
Have you tried checking if there is a short between 12V and ground, without the supply?
And check if you have continuity between jack and board. Just to check that the wires are correctly soldered. Happens with everybody.
If that does not work, it is time to check the circuit by areas. You can unsolder the trace that goes to the 555, to cut the 12V connection and check the if you have 12V at the tubes. For this test, you can even measure it with the tubes disconnected. We just want to know if there is a problem with the tubes or with the 555. If the first section of the tubes is OK, you can add the tubes and see if they light up. If it still works, the problem is with the SMPS. If not, you have bad tubes.
To check the tubes, measure the resistance of the heaters. It should be very low, but higher than 1 to 4R. If you have a low resistance at the filaments, the tube is shorted and you will have to fin another one. Normally they do not fail that way, but who knows.
Which kind of supply are you using? Does it have any kind of protection? I had some good supplies which would shut off when shorted. In some cases the heaters of the tubes look like a short. In your case, I think it will be OK because they are in series.
If it works with the tubes, but not with the SMPS, try disconnecting stuff from the 555, if it's possible. Ideally you would test if the 555 is working, without the mosfet and diode. Just to see if there is something wrong with this part of the circuit. If the 555 is socketed, you can remove it and measure if you get 12V without it (bad 555) or if it is still at 0V.
You can check if the Mosfet (IRF740) is good by measuring the resistance between pins. It should be around 740R, if I am not mistaken. A shorted mosfet is the most common problem with the SMPS I build, you just need to short the HV line and gnd and it kills the mosfet and the 555.
Good luck! This is a really nice amplifier.
PS.: I checked your board, and there are some suspicious points...the schematic was mirrored to be easier to compare. Check at the points with red circles, if there is a short between traces.
I would suggest that you use less solder, or if you can, remove some of it. The large blobs do not help, most of the time, when it looks like a nice sphere, you have actually a bad joint.
(https://i.postimg.cc/tscdMPBC/Untitled.png) (https://postimg.cc/tscdMPBC)
Looks like there's a short between 12v and ground, I'll be fixing that soldering and the soldering of the other problem spots you pointed out tomorrow morning. Looks like we're getting to the bottom of this thing.
here, see, many options for DC sockets, some metal [avoid those], some plastic body.
https://www.taydaelectronics.com/hardware/dc-power.html
please, please, PLEASE ..... take a photo/s of the thing you have built as you now have it, so that we can see the lay of the land, an overview. jacks, pots, wires, all that stuff. there is no point messing aboot w/ the high volts circuit if you are shorting your power supply at the first .. erm .. hurdle.
Quote from: duck_arse on April 30, 2022, 10:53:49 AM
here, see, many options for DC sockets, some metal [avoid those], some plastic body.
https://www.taydaelectronics.com/hardware/dc-power.html
please, please, PLEASE ..... take a photo/s of the thing you have built as you now have it, so that we can see the lay of the land, an overview. jacks, pots, wires, all that stuff. there is no point messing aboot w/ the high volts circuit if you are shorting your power supply at the first .. erm .. hurdle.
Here are some pictures:
(https://i.postimg.cc/RWZH7Fpc/Superfly-top-view1.png) (https://postimg.cc/RWZH7Fpc)
(https://i.postimg.cc/hJJQYYBv/Superflybottom.jpg) (https://postimg.cc/hJJQYYBv)
(https://i.postimg.cc/4Y2hBgjj/Superflyfrontview.jpg) (https://postimg.cc/4Y2hBgjj)
After doing some soldering to disconnect the short between 12v and ground my multimeter is still showing that the two are connected at that point. I've closely inspected the area where the rogue connection that I cleared was and it isn't connected there anymore.
How much resistance is it reading?
Remember that tube filaments have very low resistance and would show as a short if measured. If you check the resistance in ohms it will be as low as 8 to 20 ohms.
Thanks for the new pictures.
Because of the shape of the solder it is hard to tell from the picture if they are indeed touching, but I would check every solder point where there is a solder ball. If you have an utility knife you can try passing it between the traces so that it scrapes off any small contact points. I do this sometimes too, when the traces are too close together. It also will show you where the solder is connected, since you will not be able to go forward.
Quote from: thomasha on April 30, 2022, 02:32:36 PM
How much resistance is it reading?
Remember that tube filaments have very low resistance and would show as a short if measured. If you check the resistance in ohms it will be as low as 8 to 20 ohms.
Thanks for the new pictures.
Because of the shape of the solder it is hard to tell from the picture if they are indeed touching, but I would check every solder point where there is a solder ball. If you have an utility knife you can try passing it between the traces so that it scrapes off any small contact points. I do this sometimes too, when the traces are too close together. It also will show you where the solder is connected, since you will not be able to go forward.
Resistance is reading 6.7 ohms. Thanks I'll do a bit of a scrape with my utility knife and see if that does anything.
Yes, and test it without the tubes, just to be sure that you are not reading the tubes resistance
Quote from: thomasha on April 30, 2022, 02:49:23 PM
Yes, and test it without the tubes, just to be sure that you are not reading the tubes resistance
Tested without tubes. Reading between 6 and 8.2 ohms
The scraping is clearly doing something because when I test for continuity there's no beep for a couple of seconds and then eventually it's a constant tone on my multimeter. This might take a while.
This particular problem point has been scraped as you can see but the multimeter is still showing continuity. Could there be something I'm missing?
(https://i.postimg.cc/9Rd6cwgv/superflyproblempoint.jpg) (https://postimg.cc/9Rd6cwgv)
Unfortunately the short could be elsewhere, since the 12v and gnd lines are very long.
Have you tested desoldering the mosfet?
If it fails and shorts it would connect 12v directly to ground.The 6 ohms you are seeing could be a result of the resistance of the inductor+mosfet.
Quote from: thomasha on April 30, 2022, 05:59:17 PM
Unfortunately the short could be elsewhere, since the 12v and gnd lines are very long.
Have you tested desoldering the mosfet?
If it fails and shorts it would connect 12v directly to ground.The 6 ohms you are seeing could be a result of the resistance of the inductor+mosfet.
I'll try that. Unfortunately it looks like I shouldn't have bought my wire from Amazon, the wire connected to the ground lug on the 1M pot just broke off when I was repositioning the amp and a little while later the signal input wire also came apart. Live and learn I guess(I'm still having a ton of fun doing this though :))
I tested the amp and got sound! For about 5 seconds then it went silent. Still I'm like a NASA control room technician when there's a successful launch. What a rush!
So since I've been testing my Superfly build with a real guitar cabinet(Egnater 1x12) instead of a cheap test speaker, the amp works pretty damn well(loud too!). There are a few things I'll still have to debug like the random lowering in volume and the occasional what I can only describe as a "wump" sound. That being said I'd like to thank everyone here who gave advice and helped debug this build!
Video of the test(sorry in advance for my unpracticed guitar playing, I'm excited so my hands were shaking): https://www.youtube.com/watch?v=jSNoMhYVotQ&ab_channel=JonathanSilasBull
Nice! Congrats!
The "wump" could be an intermittent connection or just a bad part somewhere.
If you want to check the circuit closely, you can use an audio probe and follow the signal path. Just be careful, to not connect it to the tubes plates (unless you coupling capacitor is rated over 300v). This also helps to understand where the sound goes, where there is something weird going one and how the stages change the tone.
I would also check the voltage after the diode with a multimeter to see how high it is (200v?) or if there is some problem there. I guess it will read OK, since you have a loud output after all.
My suggestion for next builds is: use as little solder as possible! Touch trace and component with the soldering iron and touch the trace with the solder. At some point it will melt and form a thin film. That is enough. The large drops have a different wettability (the angle between the sphere and the surface), so that the drop might only be attached to the component, but not to the trace, and you will not notice it.
If you don't have much experience with high voltage circuits PLEASE be very cautious in audio probing an amp...the filter caps and many other places are exposed, potentially fatal points you can touch. In the power supply, you're looking at over 400V. What are your meter leads rated for? That PCB is a little difficult to probe, as well - it's not clear where the signal path is, as may be the case in a point to point model. Just sayin'...
Intermittent volume changes...possibly a bad drive or master pot (or dirty)...does the pilot light go up and down in brightness when the volume changes?
Quote from: GibsonGM on May 01, 2022, 07:55:45 AM
If you don't have much experience with high voltage circuits PLEASE be very cautious in audio probing an amp...the filter caps and many other places are exposed, potentially fatal points you can touch. In the power supply, you're looking at over 400V. What are your meter leads rated for? That PCB is a little difficult to probe, as well - it's not clear where the signal path is, as may be the case in a point to point model. Just sayin'...
Intermittent volume changes...possibly a bad drive or master pot (or dirty)...does the pilot light go up and down in brightness when the volume changes?
I'll let you know as soon as I add the pilot light to the build.
Quote from: thomasha on May 01, 2022, 04:21:15 AM
Nice! Congrats!
The "wump" could be an intermittent connection or just a bad part somewhere.
If you want to check the circuit closely, you can use an audio probe and follow the signal path. Just be careful, to not connect it to the tubes plates (unless you coupling capacitor is rated over 300v). This also helps to understand where the sound goes, where there is something weird going one and how the stages change the tone.
I would also check the voltage after the diode with a multimeter to see how high it is (200v?) or if there is some problem there. I guess it will read OK, since you have a loud output after all.
My suggestion for next builds is: use as little solder as possible! Touch trace and component with the soldering iron and touch the trace with the solder. At some point it will melt and form a thin film. That is enough. The large drops have a different wettability (the angle between the sphere and the surface), so that the drop might only be attached to the component, but not to the trace, and you will not notice it.
I'll see about getting(or building) and audio probe.
Quote from: GibsonGM on May 01, 2022, 07:55:45 AM
If you don't have much experience with high voltage circuits PLEASE be very cautious in audio probing an amp...the filter caps and many other places are exposed, potentially fatal points you can touch. In the power supply, you're looking at over 400V. What are your meter leads rated for? That PCB is a little difficult to probe, as well - it's not clear where the signal path is, as may be the case in a point to point model. Just sayin'...
One hand in your pocket whenever you are poking around a HV circuit, and rubber souled shoes, so there is no possible path for HV through your body.
All this excitemakes me wanna build a Superfly!
Quote from: Ben N on May 01, 2022, 11:01:51 AM
Quote from: GibsonGM on May 01, 2022, 07:55:45 AM
If you don't have much experience with high voltage circuits PLEASE be very cautious in audio probing an amp...the filter caps and many other places are exposed, potentially fatal points you can touch. In the power supply, you're looking at over 400V. What are your meter leads rated for? That PCB is a little difficult to probe, as well - it's not clear where the signal path is, as may be the case in a point to point model. Just sayin'...
One hand in your pocket whenever you are poking around a HV circuit, and rubber souled shoes, so there is no possible path for HV through your body.
Certainly good advice...avoiding a path thru your chest (and heart). It would be beyond the ability of most people to prevent a shock entirely in the 'home lab', though. ;) Even with rubber shoes. Sh*t happens - ask me how I know...
Sorry guys, I conflated replying here to the Hot Rod Deluxe post!! Different thread entirely, guess I didn't have enough coffee. It's not 400v, god no, lol. And the switching supply does offer some current limiting, tho you do need to be careful and respect the high voltage. Yes, be sure the audio probe coupling cap can handle the switch supply's B+...and yes, THIS one is probably a good build to 'listen in' and check out the audio path, being small and easy to manage.
Biggest offense I make on things like this is to have it floating loose on the desk, and trying to probe around, moving it all over...so maybe some kind of hold-down would be a good idea :)
I want to make one too, now, ha ha
Question for those who've already built and enclosed their Superfly: What size of enclosure did you end up using for yours? I have a metal enclosure I can start drilling but due to the much larger capacitor near the 12v input I won;t have as much height room for it with the enclosure I have.
Quote from: GibsonGM on May 01, 2022, 05:42:18 PM
I want to make one too, now, ha ha
Me too! Today, I received some subminis bought on ebay :)
QuoteQuestion for those who've already built and enclosed their Superfly: What size of enclosure did you end up using for yours? I have a metal enclosure I can start drilling but due to the much larger capacitor near the 12v input I won;t have as much height room for it with the enclosure I have.
It should fit in a 1590b, as used for pedals. There is plenty of room for the capacitor.
Quote from: thomasha on May 03, 2022, 05:16:27 PM
QuoteQuestion for those who've already built and enclosed their Superfly: What size of enclosure did you end up using for yours? I have a metal enclosure I can start drilling but due to the much larger capacitor near the 12v input I won;t have as much height room for it with the enclosure I have.
It should fit in a 1590b, as used for pedals. There is plenty of room for the capacitor.
Thanks! Off to Tayda I go...
Does anyone know what intermittent lowering in volume of the Superfly could be? I was testing it with a Tube Screamer today and the signal occasionally lowered in volume considerably for a few seconds and then came back to normal volume consistently while it was on. Turning the amp off and on again led to a consistent volume for a few minutes and then the lowering in volume came back. I have the transistor of the circuit in a socket I made and it feels a little bit loose, could this be part of the problem?
Anything loose could be part of it, yes, if good contact is coming and going. Even a bad cable can cause that (tip, move them around, make sure that's not it. Use 1 guitar cord direct to the firefly, make the signal chain simple). You can use the eraser end of a pencil to 'move wires and things' around to see if something is loose.
Does it do it both with the tube screamer in the signal chain, and also with it not there (completely removed)?
Any way you can make a recording/video of the issue in action?
It is probably caused by an intermittent connection.
This mostly occurs when you have a component or wire that is not properly soldered and moves, or something in a socket, that will not fit correctly.
I had the same problem with several amps, because the IC sockets will not give you a good connection with the tubes (in the end I soldered my tubes to the board, and that solved the problem.
You can verify this by tapping the tube while the amplifier is on. If there is a volume drop and it comes back when you wiggle the tube in the socket (be careful, the tube can get hot), you found the problem. You won't be electrocuted if you just touch the glass of the tube. Be careful anyways!
Sockets are not allowed for transistors and IC's in military products. They run the typical "shake and bake" environmental tests of MIL-E-810 and no one has ever seen a socket that didn't cause a problem with loosening or corrosion. The usual tests are:
1. Sinusoidal vibration, 5 Hz to 2000 Hz in three axes on a vibration table
2. Random vibration in three axes using a random noise generator powering a vibration table
3. Shock in three dimensions, both directions in each
4. Operating temperature, low and high (a Fuzz Face usually would fail to operate with consistent characteristics due to inadequate range)
5. Storage temperature (wider limits than operating temperature)
6. Salt spray
7. Humidity
8. Electromagnetic Compatibility (required for any commercial product having an internal oscillator of 9 KHz or higher)
out of a comprehensive array of tests to be called for where any possible environment is listed:
Test Method 500.6 Low Pressure (Altitude)
Test Method 501.6 High Temperature
Test Method 502.6 Low Temperature
Test Method 503.6 Temperature Shock
Test Method 504.2 Contamination by Fluids
Test Method 505.6 Solar Radiation (Sunshine)
Test Method 506.6 Rain
Test Method 507.6 Humidity
Test Method 508.7 Fungus
Test Method 509.6 Salt Fog
Test Method 510.6 Sand and Dust
Test Method 511.6 Explosive Atmosphere
Test Method 512.5 Immersion
Test Method 513.7 Acceleration
Test Method 514.7 Vibration
Test Method 515.7 Acoustic Noise
Test Method 516.7 Shock
Test Method 517.2 Pyroshock
Test Method 518.2 Acidic Atmosphere
Test Method 519.7 Gunfire Shock
Test Method 520.4 Temperature, Humidity, Vibration, and Altitude
Test Method 521.4 Icing/Freezing Rain
Test Method 522.2 Ballistic Shock
Test Method 523.4 Vibro-Acoustic/Temperature
Test Method 524.1 Freeze / Thaw
Test Method 525.1 Time Waveform Replication
Test Method 526.1 Rail Impact.
Test Method 527.1 Multi-Exciter
Test Method 528.1 Mechanical Vibrations of Shipboard Equipment (Type I – Environmental and Type II – Internally Excited)
If you sell the device to a hip-hop group, gunfire shock could be a possible test to call up.
I could vote for a number of above mentioned test methods to apply for most of groups gigs.. :icon_wink:
(especially 504.2 should be a sacrosanct proviso..)
Quote from: jma38 on April 30, 2022, 06:34:29 PM
I'll try that. Unfortunately it looks like I shouldn't have bought my wire from Amazon,
I read this on my phone without glasses as "Unfortunately it looks like I shouldn't have bought my
wife from Amazon" :P
Quote from: cab42 on May 07, 2022, 04:50:07 PM
I read this on my phone without glasses as "Unfortunately it looks like I shouldn't have bought my wife from Amazon" :P
Everyone should take this to heart. Words to live by.
"Vibration"...I took apart an old computer that was left in the barn for a few years. Re-used the nice small-gauge stranded wire. During testing, the fuzz I made, which sounded great otherwise, showed symptoms of intermittents. I debugged it XYZ ways, and could only come up with corrosion of the wire caused by being stored in a damp environment all that time, and perhaps from the shock of pulling on it while deconstructing. Once I replaced all the offboard wiring, it was fine.
What a nasty experience that was.
Quote from: GibsonGM on May 06, 2022, 02:03:41 PM
Anything loose could be part of it, yes, if good contact is coming and going. Even a bad cable can cause that (tip, move them around, make sure that's not it. Use 1 guitar cord direct to the firefly, make the signal chain simple). You can use the eraser end of a pencil to 'move wires and things' around to see if something is loose.
Does it do it both with the tube screamer in the signal chain, and also with it not there (completely removed)?
Any way you can make a recording/video of the issue in action?
Here's the video. The volume dropoff happens at around 1:26: https://www.youtube.com/watch?v=RKTRihsxvOU&ab_channel=JonathanSilasBull
Ooo, sum ting not right for sure. I'm picking up almost a rectified sound, the 'octave-like' tone. Then, of course something happens that dumps the volume.
A couple of things come to mind...something strange with the bias...maybe a polarized electro cap in the signal path backwards...a missing pulldown resistor somewhere....bad bias in the power section (?) causing that cutout (R values...). Lack of grid stoppers maybe. Does it cut out like that if left alone (not playing; no input)? Does it come back in a bit if you stop playing?
- can you affect this dropout by using the eraser end of a pencil as formerly mentioned, to move wires/sockets a bit, to see if something is loose?
If nothing seems loose, I'd try to get it to happen again, and audio probe through the preamp (triode) signal path from last preamp stage back toward input, see if there is a spot the sound seems normal while it's cutting out.
BE CAREFUL, respect the voltages where you are probing, and be sure everything you touch is fully insulated and the cap in the probe is of higher working voltage than the B+. It's helpful to have something inputting a 'noise' while you probe so YOU don't have to....a test oscillator or even tunes from a cell phone or something. It's awkward to try to pluck strings while you probe, esp. with high voltage there...
Quote from: cab42 on May 07, 2022, 04:50:07 PM
Quote from: jma38 on April 30, 2022, 06:34:29 PM
I'll try that. Unfortunately it looks like I shouldn't have bought my wire from Amazon,
I read this on my phone without glasses as "Unfortunately it looks like I shouldn't have bought my wife from Amazon" :P
:icon_lol:
Quick question for those who have built the Superfly: Do you put thermal paste on the IRF740 before screwing it to the heatsink? Would it do anything?
Yes, you have to.
The roughness of the surfaces create small gaps with air between parts, which drastically affect the heat flux.
The paste fill these gaps, and has a better conductivity than air.
On the other hand, I haven't used a heatsink in my superfly. The current flowing through the mosfet is low enough. It gets hot, but not very hot.
Quote from: jma38 on May 08, 2022, 06:34:13 PM
Quick question for those who have built the Superfly: Do you put thermal paste on the IRF740 before screwing it to the heatsink? Would it do anything?
You can even try to use MOSFET with lower Rds(on) than IRF740. Lower the resistance, lower the dissipated heat.
So today I applied thermal paste to the IRF and got it secured to a heatsink. A problem I'm running into is when I try to adjust the center tap to 185v my multimeter shows around 193v and slowly goes down until it hits 15v, the lowering in volume is directly correlated with how low the voltage drops. Not really sure how to approach this bug.
Well, good to know it's SMPS related. Is anything getting too hot?
- It could also be a saturated inductor? How much current can it supply and how high is its resistance?
- it could also be a problem with the transistor which controls the voltage...
- It could be the mosfet getting too hot (in one of my builds, using a different SMPS it would drop from 250v to 100v when hot)
- It could be a bad/leaky reservoir cap (the large electrolytic one, C6, that should be rated for more than 300v)
- It could be a short demanding too much current from the SMPS
- It could be a bad high voltage cap too (C8)
To test the SMPS alone you need to unsolder R11 and the transformers centre tap.
With them disconnected test the voltage and see if it still drops after some time. If not, the mistake is somewhere else.
If it still drops check the reservoir cap.
If you could measure some voltages would also help. Like:
- Both sider of R10, VR1, and Q1
Maybe if you replace the caps and the transistor it works.
Okay so the IRF is getting really hot. I turned the amp on for 30 seconds then turned it off and touched the heatsink and it wouldn't have burned me but it was really hot. What could be the cause of this?
Make sure you don't put too much pressure on IRF! So keep NE555 at approx 50% duty cycle, not more than that. I've had problems with SMPS in the past putting it to more than 90%, which will not allow MOSFET to cool.
Quote from: rankot on May 14, 2022, 04:31:28 PM
Make sure you don't put too much pressure on IRF! So keep NE555 at approx 50% duty cycle, not more than that. I've had problems with SMPS in the past putting it to more than 90%, which will not allow MOSFET to cool.
With further tweaking it's running stably at 126v. Not what Rick recommended in the original layout but my Superfly doesn't have any dropouts now and the IRF isn't getting hot at that voltage and the amp is plenty loud.