Sunking treble pot

[J. Ignacio]

http://www.madbeanpedals.com/projects/Sunking/docs/Sunking_ver.3.pdf

hi guys! i built this pedal using this information. I made single version pedal.

Well, pedal sounds great but i want to change (mod) the treble control with a tone control. I want to control bass and treble with this pot insted control only treble.

I searched in this forum and someone says that changing R14 (15k to 3,3k) add more bass. Others says change C22 (out cap) with a big value add more bass.

What do you think?

Thanks!

[midwayfair]

Controlling the bass and treble at the same time is not going to be possible without significant modification to the circuit and another potentiometer. The bass mod also only affects the bass in the overdrive section and not the bass of the whole circuit.

The treble works by forming, on one side, a passive high-pass filter that bypasses the 100K between the last two op amp stages with a capacitor and on the other side a treble cut in the feedback loop of the final op amp stage. There's nowhere in that system to add a usable filter that only boosts the bass without cutting all the treble as well.

[J. Ignacio]

Controlling the bass and treble at the same time is not going to be possible without significant modification to the circuit and another potentiometer. The bass mod also only affects the bass in the overdrive section and not the bass of the whole circuit.

The treble works by forming, on one side, a passive high-pass filter that bypasses the 100K between the last two op amp stages with a capacitor and on the other side a treble cut in the feedback loop of the final op amp stage. There's nowhere in that system to add a usable filter that only boosts the bass without cutting all the treble as well.

Thanks midwayfair for the explanation.

So, what do you recommend to do to add more bass at pedal? change Cap of Gain pot?