Effect Number Two: Muff Fuzz Complete
We’ll, the Muff Fuzz is complete. It looks good too. While it obviously is an amateur effort, it came out a lot better than I expected. It is named after a friend who helped me quite a few times through this project. In retrospect, RAW Squid is a bad-ass name for the fuzz box.
In my last post, I commented that I was having trouble getting everything to fit. In the end, I was able to fit everything inside this little old Hammond 1590B enclosure, but it is tight inside. I was able to keep the PCBA connectors, so everything is readily interchangeable. If I continue to build guitar effect pedals I’ll design for a slightly bigger enclosure.
The original Muff Fuzz had a volume pot, but no tone control. I elected to go without a volume pot. That may be a mistake, as the output from this pedal is louder than straight through bypass. If required, we can add one later. I built this effect with true bypass. I don’t know how the original Muff Fuzz bypass was set up.
On the circuit board, you’ll notice the white connector. The connector hosts a plug in module for the clipping diodes. You can see the clipping diodes in the schematic diagram below. I installed the clipping diodes in a plug in module so that the pedal is easy to experiment with.

The most basic mode (1) is no diodes. Without clipping diodes the circuit is essentially a Fuzz Face with alternate component values. Configured this way, the sound is similar to, but has more buzz than a Fuzz Face. Adding the back-to-back clipping diodes, (2) the circuit is as shown above. Lastly (3) I made a a three diode version where one of the legs has with two diodes in series. A lot of folks call that the tube screamer mod because the diode clipping is asymmetrical.
We could make even more versions, if we were to toss germanium diodes and filter capacitors into the mix. Also, I suspect that tone control could be added in place of the 2.7k ohm resistor.
I’m eager to have this effect pedal evaluated by an objective and seasoned guitar player.
