Tech21 Double Drive build - question

[RickL]

I built this using the schematic available here: http://www.axiomdrift.com/schematics/DD%20PN.gif

It works, in the sense that it distorts, it's loud and all the controls have an effect but I'm curious about the pot labelled "tone". It appears to be just another level control, simply changing the resistance between the output of the 4th opamp and the input of the 5th. In practice it also seems to operate that way. Any tonal differences seemed to be more due to the increased volume than any actual frequency shaping.

I didn't get a chance to test it much because the bridge of my whammy equipped test guitar broke (!) shortly after I started testing.

My question is to anyone who has played the commercial version of this pedal. Does the tone control work the way I've described or could there be a slight error in the schematic? Note, I will not entertain the idea that I could have made an error in building it  :twisted: .

[cd]

You have a build error, I've breadboarded the circuit and the tone control works fine.  It dumps a ton of highs to ground, since it's just a variable low pass filter into a buffer stage (like a RAT).