Where can I put a gain control here?

[zener]

I'm planning to use the LPB http://www.generalguitargadgets.com/v2/diagrams/lpb2_sc.gif as my preamp through a TDA power amp that would make my practice amp. The TDA2003 doesn't like the LM386 going into it. It produces a lot of noise. I messed up with buffers in between and it only became worse.

I noticed the same thing with JFET buffer/preamp. The only thing it works with is a BJT.

I've drilled my amp chassis long ago. It is supposed to accomodate pots for preamp switch for clean/drive, gain, volume pot, bass, treble and master volume.

The problem is I don't know where I can hook up the clean/drive and gain pot in the LPB. Is that a variable resistor on the emitter?

Thanks for any help :wink:

[zener]

Just keeping this post alive, I hope you don't mind.    

[petemoore]

You could try in series resistance before the input cap, or a pot wired like a volume pot [see EZ Face with input gain control].
 I never tried playing with the emitter to ground resistance, it would have to affect the gain, you could try it just to see what it does.
 I think the best thing is the guitar volume control. the input blend is nice to limit the maximum gain on a high gain circuit at input, so full on with the guitar doesn't mush the distortion But I think the LPB sounds good at full gain, If it's too much, put one of the above suggestions on it, or possibly build another booster and series them, the first ones volume control would be a gain reduction device for the secone stage.