Jen Harmon Booster

Here's a really unique overdrive from the Italian manufacturer Jen from the late 70s. Think Tube Screamer meets Big Muff. It sort of reminds me of a DBA design (only more stable and not as over the top) with a whole mess of transistor stages pushing a BMP style tone stack. Originals used BC318c transistors, but others in the 400-500 hfe range can be used. Here's the schematic for reference.

Gretsch ControFuzz

For Fuzz Friday I give you the ControFuzz from Gretsch. Originals are pretty rare and it's an fairly unique design based around a single 4558 chip. I found a build report from LucifersTrip over on DIYSB, and he suggested a slight mod to the Distortion control that improves the circuit, so the layout below is based on that.