This is a library of perfboard and single-sided PCB effect layouts for guitar and bass. I'm not an electrical engineer by any stretch of the imagination, just a DIY'er who likes drawing layouts. It is meant for the hobbyist (so commercial use of any of these layout is not allowed without permission) and as a way to give back to the online DIY community.

Friday, July 26, 2019

Foxx Select-A-Fuzz

Happy Fuzz Friday, everybody! The Select-A-Fuzz is a pretty interesting fuzz box from Foxx. It has a rotary switch to select the input cap (the larger the cap the fuzzier the effect), followed by a Fuzz Face-esque stage and an extra gain stage. Here's the schematic for reference with some good notes on alternative transistors and voltages. D1 is silicon in the original unit, but a germanium diode will take the edge off a bit.


  1. Works. Used the MPSA06 transistors with hfe = 175. I don't have enough gain controller, "fuzz" pot affects the frequency character. Perhaps it is worth putting pot 100K on input (as in EQD Dirt Transmitter) or replace R4-3K3 with a pot 5K (as FuzzFace). I'm going to give it a try. Sorry my english.

    1. Unfortunately, the "Fuzz Face-variant" is not working. A potentiometer on the input (change the volume of the guitar) works well.

    2. The "Fuzz Face" looks like it has a bit different circuit from what I can discern. I think the "Fuzz Face" fuzz knob would be roughly where the 3k3 resistor is on the Select-A-Fuzz...

  2. It remeber the seymour duncan tweek fuzz.