Comments on: Blues Driver

By: Fernando (Argentina)

Fernando (Argentina) — Wed, 23 Sep 2009 03:34:21 +0000

Just build it, it works fine, and i didn´t have trouble with that fx pedal. I used J201 fets and 2n3906 and 2n3904 Bipolar transistors. Thanks for that beautiful project!

By: njkmonty

njkmonty — Thu, 04 Jun 2009 11:35:58 +0000

ive heard that the Keeley modded version of this is great. Ive built by self a ts808 clone with his mods. Is it worth doing this pedal if i already have a tubescreamer, and if so does anyone know the keeley mods?
cheers
ps which is the recommende version?

By: cris

cris — Sun, 11 May 2008 00:41:44 +0000

you have a great review of op amps. Do you know where I can by an adopter to go from a straight pin configuration to a typical 4×4? Mone Allum,coom has them for 6.49 USD each and I want to buy in bulk. This could help you also.

By: gaussmarkov

gaussmarkov — Tue, 13 Nov 2007 15:45:46 +0000

Hi sebastion, I am happy to help with debugging. The best place I know for doing that is on Aron's forum. Send me a personal message there and I (and others) will try to help. Be sure to follow the on-line instructions about the information that you should provide (e.g., voltage readings). Cheers, gm

By: sebastian

sebastian — Tue, 13 Nov 2007 03:33:19 +0000

hi, i’m trying to “debug” my circuit, and i really need some help, i have already check the voltage of all transistors (jfet 2n5457; 2n3904; and 2n3906) and it looks good, but the volume in the out is lower than the input, even with gain and level at max.

thank and sorry for my english (im from argentina)

By: gaussmarkov

gaussmarkov — Tue, 13 Nov 2007 00:02:57 +0000

Hi ray,

That’s a fine idea. And it’s one of the things that I was hoping people would do: take the circuit and experiment. Your suggestion for less (and asymetrical) clipping is just the thing.

I hope you will try it and report back what you think. Maybe socket the diodes and try various setups?

Cheers, gm

By: ray

ray — Mon, 12 Nov 2007 23:01:12 +0000

hey gm, why not just drop the buffers and make a stripped down version and drop out the one diode for a bit less fizz?

By: gaussmarkov

gaussmarkov — Sun, 16 Sep 2007 17:42:54 +0000

Hi Chris,

I have played through both and found no discernible difference. But there are probably times when it matters. I didn’t do a really careful study.

FWIW, I have redesigned this circuit with an input buffer (like the original) that raises the input impedance from approximately 200K up to around 700K. That does make a difference for my setup. I will post the modified layout soon.

But if you have a low impedance source (like another stompbox), then it won’t matter much.

All the best, gm

By: Chris Daudet

Chris Daudet — Sun, 16 Sep 2007 08:45:42 +0000

Hi,

I was wondering if there are any sounding or performance differences between the circuit with the Opamp Vr supply and the one without it.

Thanks.

By: gaussmarkov

gaussmarkov — Mon, 20 Aug 2007 21:57:11 +0000

Hi Rockey,

That’s a good question for a DIY forum like Aron’s at http://www.diystompboxes.com/smfforum/

All the best!