How to add tone control to my VOM Champ?

[Regis]

I would like to implement a treble cut tone control on my VOM Champ, after the preamp tube rather than in between the two preamp sections. I'm thinking it would let me shape the distortion coming out of the preamp a little better.

I'm not sure how to wire though, can someone help? I've posted the schematic and put a red dot where I think it would go but again I'm not sure.

I'm guessing it will be a 250k pot and something like a .005 cap.

Thanks,

Regis

[Jag]

Totally flying blind on designing a tone control but, does this work?

Regis Champ tone control

I will delete if way off base. Just wanted try this.

[Jag]

Sorry, that should be on the other side of the coupling cap.

[tubeswell]

What about making that bleeder cap smaller (say 330-390pF - mica cap)? You might loose too many highs a 470nF cap, but maybe I would put it after the coupling cap, or try a 390pf in parallel with a 250kA pot between the coupling cap and the grid leak resistor to V2?

[Bruce / Mission Amps]

Something like this would work.
You'll loose a little gain so you might want to up the cathode bypass caps to 2.2uF instead of 470nF.

[Regis]

Thanks guys, for the replies. Bruce, I'll give that a try.

Regis