School me on the Colorsound Wah

[soggybag]

I just built up a Colorsound Wah. It uses a 100K pot for the wah effect. At this point I'm using a regular pot and turning it by hand for testing. It's all on the breadboard for now.

Seems like the useful range is a about 0 to 20K. Though Anything less than about 470 ohms is not very useful. Above about 20K seems to place the effect low enough where it doesn't have much effect.

How can I calculate the frequency range of the filter? I'd like to get more out of the sweep. Or at least figure out where the sweep should be.

Also, I found a post from sometime ago where the author mentions adding a resonance control to this circuit. There wasn't schematic or a description. I'm wondering how this might be accomplished.

[boogietube]

The only info I can remember reading is here:

http://www.diyguitarist.com/

He did a DIY pedal with the colorsound wah. There is a  "Q" jumper on the board.

The article is called "Building a Wah Pedal From Scratch" under "a sampling of stompboxes i have built"

There is a full PCB layout that may answer your questions. He used a 100k HotPotz II I believe.
Sean

[arma61]

Also, I found a post from sometime ago where the author mentions adding a resonance control to this circuit. There wasn't schematic or a description. I'm wondering how this might be accomplished.

Are you talking about this ?

http://www.diystompboxes.com/smfforum/index.php?topic=66607.msg529759#msg529759