Based on the Mid-Fi Clari(not) with added feedback, denoising, and additional filtering, modified vactrol circuit. One of my favorite effects ever.
+tilt.jpg)
Unmodified Clari(not) schematic. I'll work up a full modified schematic in the future. In the mean time start by increasing C8 to .33uF for lowpassing the PT2399. It's a damn noisy chip. I tried four before settling on one.
I didn't actually do this on this on this one, but a simple input attenuator would work well for a gain control for the fuzz. You could flop the input through a input attenuator (let's say 100k) with a 3PDT, whilst flooping the fuzz channel. The fuzz does sound pretty good.
Video of the finished product:
10 min nerd talk with a prototype: