Tube boost + overdrive running off a 9 volt battery

Started by dano12, December 11, 2007, 07:51:24 PM

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IbanezRG95

I was wandering what the simplest voltage boost circuit is to get the 9v from a boss adapter up to 12v for the heaters?

also, has anyone tried this circuit with a 9au7? from what I have read it is the same as the 12au7 except the heater runs on 4.5v/9v instead of 6v/12v

and I would just like to share this incredibly clean build that I found on the net http://www.flickr.com/photos/timpatterson/5518405003/in/photostream/

texstrat

Well here it is, finally got it stuffed in the 125B box. Running on 12V and using a 12ua7a RCA tube. Went with a Sci-Fi theme  :icon_mrgreen:





Renegadrian

No big difference,I made on with 9au7. my tube seemed to lack some volume, it sounded a lil more compressed and a lil weaker - but it could the tube I used...
---------------------
texstrat, you pedal looks killer!!!
Done an' workin'=Too many to mention - Tube addict!

texstrat

Thanks, it has been a fun build. I am now trying to figure out what to build next. I think I am going to build another ruby 0.5 watt amp in an Altoids tin.

zambo

I wonder what happens if I .......

candletears7

Thanks mate! I just didn't know if different voltages had to be fed to different pins. I'll experiment with hitting the whole shebang with higher voltages. I don't want to get into anything more than medium gain, I have the Minstrel for that. If this puts out a nice fat AC/DC sound at most I'll be happy.

And while we're here, a big thankyou to you personally for your layouts you've done in the past. When I was just getting into DIY and building vero layouts, I came across yours and used them on a couple builds - so cheers! :)

Quote from: Renegadrian on March 03, 2012, 08:50:05 PM
you replied to your own question man! The heaters (pins 4-5) must be fed to 9 or better 12v. that's mandatory, you dont want to blow a tube!!! The other parts would benefit of more voltage! tubes were usually intended to run on high voltage, and you can read a lot of their curves thru their datasheets - low voltage experiments are quite unknown (we can say we are the piooniers of that...) so we can just argue the behaviour at low voltage...the main benefits of higher voltage at the anodes
is that you feed more "air" - also some 12ax7 can react better.

danamoose

Texstrat what functions do your switches control? One looks to be negative feedback, and can't tell on the other one. thanks!

texstrat

The boost switch is a negative feedback and the other is a lite - dark switch replacing C1. I used a DPDT switch with a 0.1uf and 0.022uf.

rugeb

#2848
Quote from: candletears7 on March 03, 2012, 07:52:40 PM
Thanks to all for the extensive work on this great little circuit!

Yesterday I breadboarded the stock Valvecaster from Dano Beavis' schematic, and it sounds pretty damn good.

If you have a minute, read my progress in the search for the ultimate low gainer.
Previously I was using a Paul C. Tim for my low gain needs, but I run a 50w Plexi set to absolute clean, but loud. Zero breakup from the amp, so I felt that the Tim, while brilliant when combined with a bit of amp dirt, was not the pedal for me. So I got a vintage Marshall Bluesbreaker pedal. Again, great pedal particularly with mid scooped amps like a Fender Twin, but the Plexi has it's share of mids in its' natural tone, and the Bluesbreaker pedal/Plexi amp combo is a little too boxy in the mids for me.

I ran the Valvecaster on the breadboard through my Plexi and it's very good. I was lucky enough to receive 4 vintage 1950's 12AU7's out of an old Baldwin organ, courtesy of one of the wonderful BYOC forum members. However, as noted, being that the circuit is optimised for single coils, with my humbucking guitars there was just WAY too much bass, bordering into soft farty fuzz territory in the low end. Not good. I wound all the bass out of the amp, and got a great rocking Malcom Young sound.

I have been comparing the JuanSolo/Cleggy Boobtube schematic against Rick Holt's Valvemaster schematic, and I believe Rick's mods could be quite an improvement on the intial Matsumin design.
Having the gain pot after the first Valve stage (here in Australia we call 'tubes' "Valves") seems to make sense to me in that it allows the circuit to ramp up it's total gain level before bringing it down, as opposed to bleeding signal to ground from the get go.

Today I will make some modifications to the Valvecaster circuit on the breadboard, and aim to do the following:

1) Work out if dropping the input cap OR the coupling cap (both 47n in the initial schemo) to a lower value is better for removing unwanted low end frequencies. I'm imagining that I'll be putting that component on a switch to work for SC's/HB's as the need arises. The JuanSolo/Cleggy circuit uses a 10n for HB guitars, so I'll try that.

2) I want to hit the circuit with various voltages. Right now it's pulling 9v straight out of a 1-Spot. I use a Cioks AC10 for my main board, and I believe I have a 9v, 12v and 18v tap free on the powersupply.

Before I get into this, I see on the JuanSolo/Cleggy schematic that there is 12v going to Pin 5 of the valve, while 23v goes to Pins 1 and 6 of the valve. I have read the thread pretty extensively, so may have missed the answer if it already exists, but what are the sonic benfits of sending different voltages to different Pins of the valve? (I have done a lot of DIY pedals with transistors, FETS, opamps etc..., this is my first valve circuit). Question - Can I just try different voltages to the whole circuit, eg: 9v, 12v, 15v, 18v, 24v? Or can only one part of the valve only be fed with 9v, while other parts of the valve can take higher voltages?

I have a great hammertone Pedalenclosures enclosure to use for this project. I plan to have the valve up back in some kind of protective rail, and to rock the sh*t out of this thing. If it works well, then I hope this does my low to medium gain tones for me. My medium to high gainer is a Kingsley Minstrel, and man that pedal is off the hook. So, another valve pedal to pair with it seems like the go.

Thanks for reading, any answers to my question would be great, and I will post pics once I'm done.
Cheers!



Add a voltage doubler: 9v to heater, 18v to plates.



Use a LTC1054 to get 0,5 mA instead of the 0,1mA an ICL7660S can handle.

IbanezRG95

Quote from: rugeb on March 04, 2012, 04:31:14 AM
Quote from: candletears7 on March 03, 2012, 07:52:40 PM
Thanks to all for the extensive work on this great little circuit!

Yesterday I breadboarded the stock Valvecaster from Dano Beavis' schematic, and it sounds pretty damn good.

If you have a minute, read my progress in the search for the ultimate low gainer.
Previously I was using a Paul C. Tim for my low gain needs, but I run a 50w Plexi set to absolute clean, but loud. Zero breakup from the amp, so I felt that the Tim, while brilliant when combined with a bit of amp dirt, was not the pedal for me. So I got a vintage Marshall Bluesbreaker pedal. Again, great pedal particularly with mid scooped amps like a Fender Twin, but the Plexi has it's share of mids in its' natural tone, and the Bluesbreaker pedal/Plexi amp combo is a little too boxy in the mids for me.

I ran the Valvecaster on the breadboard through my Plexi and it's very good. I was lucky enough to receive 4 vintage 1950's 12AU7's out of an old Baldwin organ, courtesy of one of the wonderful BYOC forum members. However, as noted, being that the circuit is optimised for single coils, with my humbucking guitars there was just WAY too much bass, bordering into soft farty fuzz territory in the low end. Not good. I wound all the bass out of the amp, and got a great rocking Malcom Young sound.

I have been comparing the JuanSolo/Cleggy Boobtube schematic against Rick Holt's Valvemaster schematic, and I believe Rick's mods could be quite an improvement on the intial Matsumin design.
Having the gain pot after the first Valve stage (here in Australia we call 'tubes' "Valves") seems to make sense to me in that it allows the circuit to ramp up it's total gain level before bringing it down, as opposed to bleeding signal to ground from the get go.

Today I will make some modifications to the Valvecaster circuit on the breadboard, and aim to do the following:

1) Work out if dropping the input cap OR the coupling cap (both 47n in the initial schemo) to a lower value is better for removing unwanted low end frequencies. I'm imagining that I'll be putting that component on a switch to work for SC's/HB's as the need arises. The JuanSolo/Cleggy circuit uses a 10n for HB guitars, so I'll try that.

2) I want to hit the circuit with various voltages. Right now it's pulling 9v straight out of a 1-Spot. I use a Cioks AC10 for my main board, and I believe I have a 9v, 12v and 18v tap free on the powersupply.

Before I get into this, I see on the JuanSolo/Cleggy schematic that there is 12v going to Pin 5 of the valve, while 23v goes to Pins 1 and 6 of the valve. I have read the thread pretty extensively, so may have missed the answer if it already exists, but what are the sonic benfits of sending different voltages to different Pins of the valve? (I have done a lot of DIY pedals with transistors, FETS, opamps etc..., this is my first valve circuit). Question - Can I just try different voltages to the whole circuit, eg: 9v, 12v, 15v, 18v, 24v? Or can only one part of the valve only be fed with 9v, while other parts of the valve can take higher voltages?

I have a great hammertone Pedalenclosures enclosure to use for this project. I plan to have the valve up back in some kind of protective rail, and to rock the sh*t out of this thing. If it works well, then I hope this does my low to medium gain tones for me. My medium to high gainer is a Kingsley Minstrel, and man that pedal is off the hook. So, another valve pedal to pair with it seems like the go.

Thanks for reading, any answers to my question would be great, and I will post pics once I'm done.
Cheers!



Add a voltage doubler: 9v to heater, 18v to plates.



Use a LTC1054 to get 0,5 mA instead of the 0,1mA an ICL7660S can handle.


would this one work http://australia.rs-online.com/web/p/charge-pump/0526763/
just asking cause it says output voltage is -5 on the page?

Govmnt_Lacky

Quote from: rugeb on March 04, 2012, 04:31:14 AM
Use a LTC1054 to get 0,5 mA instead of the 0,1mA an ICL7660S can handle.

I believe you meant to say "Use the LT1054 to get 0,1mA."

The 1054 can only handle up to 100mA.

Unless you can link to the LT"C"1054. I could not find this.
A Veteran is someone who, at one point in his or her life, wrote a blank check made payable to The United States of America
for an amount of 'up to and including my life.'

rugeb

#2851
Use LT1054:
 9v input => 18v output
12v input => 24v output

Yes, the LT1054 can only handle up to 100mA.


See post: http://www.diystompboxes.com/smfforum/index.php?topic=60871.0

-------------------------------------------

Another voltage doubler with 555 (up to 200mA):





EDIT:
For 18v testing, a easy solution:  :icon_idea:




iccaros

Quote from: texstrat on March 03, 2012, 09:38:00 PM
Well here it is, finally got it stuffed in the 125B box. Running on 12V and using a 12ua7a RCA tube. Went with a Sci-Fi theme  :icon_mrgreen:




where did you get that heat sink? that is nice and small with lots of fins.

runmikeyrun

Had a wicked hum in my valvy, didn't matter what PS I used or where in the house I was using it.  I simply added a 7812 rectifier with (2) 220uF caps (one from the dc jack to ground, the other from power out to ground) and my valvy is SILENT.  Dead silent.  I just thought I'd throw that out there in case anyone else was having an issue. 
Bassist for Foul Spirits
Head tinkerer at Torch Effects
Instagram: @torcheffects

Likes: old motorcycles, old music
Dislikes: old women

texstrat

Quote from: iccaros on March 04, 2012, 11:31:22 PM
Quote from: texstrat on March 03, 2012, 09:38:00 PM
Well here it is, finally got it stuffed in the 125B box. Running on 12V and using a 12ua7a RCA tube. Went with a Sci-Fi theme  :icon_mrgreen:




where did you get that heat sink? that is nice and small with lots of fins.

Steve:

I bought them on Ebay for another project and thought they might fit, they did. If you are interested, I can dig up the box and let you know who manufactured them.


Renegadrian

Quote from: candletears7 on March 03, 2012, 10:40:38 PM
...a big thankyou to you personally for your layouts you've done in the past. When I was just getting into DIY and building vero layouts, I came across yours and used them on a couple builds - so cheers! :)

Wow so nice to read such nice words...I am so pleased when someone appreciates my layouts and uses them with good results!!!
Done an' workin'=Too many to mention - Tube addict!

rugeb

Quote from: runmikeyrun on March 04, 2012, 11:52:48 PM
Had a wicked hum in my valvy, didn't matter what PS I used or where in the house I was using it.  I simply added a 7812 rectifier with (2) 220uF caps (one from the dc jack to ground, the other from power out to ground) and my valvy is SILENT.  Dead silent.  I just thought I'd throw that out there in case anyone else was having an issue. 

Ok runmikeyrun: Tested!  ;)
Now, the schematic:




rugeb

Quote from: Renegadrian on March 05, 2012, 09:13:47 AM
Quote from: candletears7 on March 03, 2012, 10:40:38 PM
...a big thankyou to you personally for your layouts you've done in the past. When I was just getting into DIY and building vero layouts, I came across yours and used them on a couple builds - so cheers! :)

Wow so nice to read such nice words...I am so pleased when someone appreciates my layouts and uses them with good results!!!

 
I'm also a follower of Renegadrian... 
Adriano: from Spain, thanks for all!  ;)


kurtlives

Quote from: rugeb on March 05, 2012, 12:13:45 PM
Quote from: runmikeyrun on March 04, 2012, 11:52:48 PM
Had a wicked hum in my valvy, didn't matter what PS I used or where in the house I was using it.  I simply added a 7812 rectifier with (2) 220uF caps (one from the dc jack to ground, the other from power out to ground) and my valvy is SILENT.  Dead silent.  I just thought I'd throw that out there in case anyone else was having an issue. 

Ok runmikeyrun: Tested!  ;)
Now, the schematic:




Right hand side cap is backwards.
My DIY site:
www.pdfelectronics.com