spi
Well-known member
This one was a long time coming. I wasn't expecting to build it, but around 2 years ago I asked @fig for one of his Fig Labs stickers, and he sent me stickers, picks, and this PCB. When fig gives you a pcb and says "go build something", you go build it.
It took a while gather parts because it uses stuff I don't usually have on hand, such as germanium transistors, transformers, ferrite beads, and a p-channel mosfet (which was surprisingly hard to find in to-92 so I took a shot with a random SMD part and it worked).
Also, I had some issues with boxing it because I didn't plan well for the jack placement (described here: https://forum.pedalpcb.com/threads/frustrating-off-board-wiring-for-eva.19327/). So I had to get another enclosure, paint it and wait until I was ready to do a batch of epoxy finishes.
Almost two years later, and it's complete!
This circuit divides the signal into two independent fuzz circuits, and allows blending them together. The germanium path uses a jfet to split the signal into 2 selectable phases, and then both a NPN and PNP transistor for the fuzz section The silicon side has a buffer, then goes through one coil of the transformer (I don't know if this is to simulate a pickup or what), and then into what looks similar to a silicon fuzz face, but with the addition of a diode (not something I'd seen before).
To me the germanium side sounds smooth and fuller in the low end, and the silicon side sounds a bit rougher. Blended together I noticed you can get some almost octave like tones on the upper frets, depending on the phase setting. Each side sounds good on its own and blending allows a lot of versatility.
It took a while gather parts because it uses stuff I don't usually have on hand, such as germanium transistors, transformers, ferrite beads, and a p-channel mosfet (which was surprisingly hard to find in to-92 so I took a shot with a random SMD part and it worked).
Also, I had some issues with boxing it because I didn't plan well for the jack placement (described here: https://forum.pedalpcb.com/threads/frustrating-off-board-wiring-for-eva.19327/). So I had to get another enclosure, paint it and wait until I was ready to do a batch of epoxy finishes.
Almost two years later, and it's complete!
This circuit divides the signal into two independent fuzz circuits, and allows blending them together. The germanium path uses a jfet to split the signal into 2 selectable phases, and then both a NPN and PNP transistor for the fuzz section The silicon side has a buffer, then goes through one coil of the transformer (I don't know if this is to simulate a pickup or what), and then into what looks similar to a silicon fuzz face, but with the addition of a diode (not something I'd seen before).
To me the germanium side sounds smooth and fuller in the low end, and the silicon side sounds a bit rougher. Blended together I noticed you can get some almost octave like tones on the upper frets, depending on the phase setting. Each side sounds good on its own and blending allows a lot of versatility.
