more gain on M15

Hi,

your question was incomplete - at least in my eyes.

Because both - the clean und crunch channel - have a volume pot but there is no gain pot as you wrote...

By your second posting now I know you mean the crunch channel.

Using the JTM 45 values would lower the gain of this stage...

You can try several things:
- Rising R11 to ... 180k
- A capacitor in parallel to R12 (µ1 to 10µ). You have to choose for the bass response you like.

- Another method (which I would try first) would be changing the places of R13 <-> R14 or better replace them with a 100k trim pot an find the best position. Then measure the two partial resistances of the trim pot and replace them again with fixed resistors (nearest values are sufficient).

BTW: I help people building the kits "as they are thought to be".
Normally I don't contribute to modding questions, because my opinion is if you are modding something you should know and understand what you are doing.

In your case this would mean (for example) that you understand what happens if you are changing the value of the cathode and/or anode resistor of a standard gain stage.
Because no one else can take responsibilty if you are doing such things...
I hope you understand this in a positive way.

Bernd

I have modified my M15 so that the clean channel cascades into the drive channel via a capacitor and resistor, can't remember the values now, but I did try a few before I was happy. I run the gain on about half now and I have more than enough overdrive to suit me, and I like it heavy.