DIY volume pedal, expression pedal insert?

[brand0nized]

My biggest problem with trying to make my own volume pedal was the gears and mechanisms.

Then I had an idea of building all the electronics for the volume pedal into a small enclosure, like a 1590LB, and have a jack for an expression pedal in place of the potentiometer.

What do you guys think about this? How well would this work?

[WaveshapeIllusions]

You'd want two mono jacks and one stereo. Connect the stereo ring to one tip and the stereo tip to the other. Connect all the sleeves together. That will give you a simple passive volume pedal. I've used the Moog EP2 for one like this. It worked pretty well.

One concern though, is the taper. Most expression pedals are linear taper; log is preferred for volume. You can use a tapering resistor to modify this. Look up RG's 'The Secret Life of Pots' on Geofex.

Hope this helps.

[brand0nized]

Thank you for the insight! Is it possible to change the pot inside the exp pedal?

[pinkjimiphoton]

yes, as long as you find one that's gonna interface well...with the toothed gear or whatever.

you can use this to figure out how to get different resistances, too. just patch in the two values you need...say 1meg pot, and what you want...
say 37 k pot.

you'd need a 38421.599k resistor. 39k is the next standard value.

http://www.sengpielaudio.com/calculator-paralresist.htm

read the secret life of pots on RG's most excellent geofex.com site..

there's a lot you can do. a resistor in parallel will have a weird taper, but sometimes it can get you out of a sticky wicket.

also check his LERA article.