This is a simple distortion module, simple but yet quite usable. There are two switches to select soft clipping or hard clipping (or both of course), and a potentiometer to amplify and overdrive the signal.
Unfortunately there are no building instructions for this module, but at least you'll find the schematic, some photos, and some comments.
The finished module, without a faceplate.
Testing the dist.
First the original triangle like wave form. Second soft clipping with some amplification. Third hard clipping with some amplification. Fourth overdrive of the signal. Then soft and hard clipping as well as overdrive, and some filter and resonance tweaking.
I thought it would be nice with two distortion modules, so I made another but with germanium diodes and a NE5532 to get a slightly different sound.
First the original triangle like wave form. Second soft clipping, using silicon diodes, with some overdrive. Third soft clipping, using germanium diodes, with some overdrive.
The finished dual distortion module, still without the faceplate.
The finished dual distortion module mounted in the modular.
That's it! Have fun and create extra harmonics!