Voltage controlled grunge module

Spotted in the Electro-Music forums, oldmanfury converted an old guitar distortion pedal into a voltage controlled synth module using an Arduino & digital potentiometer chip –

I’ve talked about doing this forever, so I am happy to finally be able to introduce my 95% complete, voltage controlled DOD Grunge FX-69!  Frac-rack modular synths have been in my opinion missing a voltage controlled distortion module, with wave-folders being about as close as I could find.  I had a torqued FX69 sitting around, and figured it would sound wonderfully terrible in my synth setup.  I’ll spare you the history on all of the approaches I thought about taking to add voltage control to an old pedal, and just say that the Arduino Duemilanove along with an analog devices AD5204 I2C controlled digital pot is perfect for this.  You end up with a fantastic, easy to program microcontroller with 4 analog inputs that control four 100 kohm potentiometers, and even have PWM outputs you can use for indicator LED’s.  This design could work for any guitar pedal.  And the how-to on the Arduino site did all of the heavy lifting for me!

Looks like a sure-fire method for creating some unique sounds. Check out the project’s blog entry for more details.

More:

Collin’s Lab: Guitar pedal modding with Arduino