parametric EQ and a wah

[Sauerkret]

This is a schematic of a parametric EQ.
I would like to us it as a bandpass filter (wah)

The filtering section is basically a Craig Anderton super tone control wah.

Would I need to modify this circuit? Could I remove the mid control (green box) because I'll use the dual pot to sweep through the mids. And how would I wire this up?



Kind regards, Eric

[Sauerkret]

Bump

[fuzzo]

The mid control seems to be the boost/cut control. But you can keep just the bandpass filter made by the three AOPs and sending your input signal into the first. The dunlop Q zone ( is made in the same way) . Look at its schematic , that's very close.

[Ben N]

You could make the mid pot a trimmer.

[Sauerkret]

another thing that i am curiouse about is why there is a Dual  potentiometer instead of a regular single pot.
is this crucial to the filtering? and why would that be so?

thanks, Eric.

[Shepherd]

Anderton addresses the idea of turning the Super Tone Control into a Wah pedal in his book.  If you don't own the book already, it might be worth picking up.  In any event you need to find a treadle that will accommodate a dual ganged potentiometer.

[puretube]

another thing that i am curiouse about is why there is a Dual  potentiometer instead of a regular single pot.
is this crucial to the filtering? and why would that be so?

thanks, Eric.

State Variable Filter*: no need for dual pot - you can use dual-vactrol or 2 OTAs, too...
(or 2 PWM-ed CMOS switches, see "MXR")




*search...

[fuzzo]

Thanks for the specific works that I didn't know.

with that word google gave me a lot of things

[puretube]

Thanks for the specific works that I didn't know.

with that word google gave me a lot of things

Yep: the most interesting thing in the first schemo of the >1.5 million google-returns is: Rf1=Rf2 ...