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, October 28, 2016

Smallsound/Bigsound Team Awesome! Fuzz Machine

For Fuzz Friday here's another cool design from Brian at Smallsound/Bigsound. It's a unique silicon/germanium hybrid fuzz box with all kinds of options. This was traced over on Freestompboxes and Brian was kind enough to chime in and shed a little light on the circuit. There have been a couple versions of this circuit with both PNP germaniums with a charge pump and this version with NPN germaniums. The dip switch is there to give the option of bypassing the input buffer. For the buffer to be on, switch 1 down and 2 and 3 up. To bypass the buffer, switch 1 up and 2 and 3 down. There are a couple question marks around the circuit still, specifically 2 diodes (which are probably schottkys) and one larger capacitor (probably 330nF), so socket things and experiment. It seems to be a very tweakable circuit, and it work well on guitar and bass.



  1. I've obtained a couple hundreds of MP35 somehow, hope to verify it this weekend.


  2. I just finished build this one and also own the original so this one is VERIFIED!

  3. I was reading in other forums that if you even can't find BAT41's in your location you can replace them with Any Germanium diode. Any Silicon Schottky diode (eg. 5817)
    Replace 2x BAT41 with one std. silicon diode, zener would be ok.

  4. if dip 1 is up and 2 and 3 down, the buffer is active, right? So if I put a jump in dip1 the buffer will always be active?

  5. hi! i have a strong feedback when i turn the clean pot at full range, can't find the sourse of problem