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, February 9, 2018

DOD Carcosa

Happy Fuzz Friday, everybody! Here's a new fuzz circuit from DOD. It's a cascaded transistor design offering a wide range of tones with tons of output. Should be an easy fit in a 1590B.


  1. hi,
    sorry i kwon i'm not in the right place, but i have some questions to ask you about commercial use of yours layouts ! where can we speak ? any chat or private place ?

  2. Verified! It ran the first time.
    My transistors 2n5089 had 670HFE, the circuit gets too much gain, it gets a lot of background noise, and the distortion is excessive and it loses definition. I made a radical change for a BC549C with 420HFE, the noise disappears but only gave distortion with the maximum pot, I ended up with some BC550C with 500HFE, it sounds a lot like the original carcosa but I'm still not satisfied, I'm going to test more iransistor, but I think the ideal gain will be between 500 and 550HFE.

  3. I built the tagboardeffects vero and I agree. Transistor gain is crucial on this thing. I have bc109c's around 500ish hfe in it right now but I'm still not satisfied. The noise is gone at least. I'll post back when I hit on the magic #'s.

  4. Verified on trans 2n5088 with 510-540 Hfe. On the turned at least twirls very soft load, like overdrive. Then there are many harmonics and fuzz. Sometimes, at the maximum settings, a shout appears.

    1. @DeadTree "Sometimes, at the maximum settings, a shout appears." Do you mean transistor oscillation like a screaming or whistle? I experienced the same (with 2N5088 hfe ~550). If I turn down the guitar volume the shout disappear. It's similar to FuzzFactory's behavior. This is really annoying.

    2. Update! I replaced the BAT46 with BAT41. Now the pedal is more stabile and rigid. Sounds like the original, but the oscillation don't disappear fully.

  5. Hello all.
    I have tried this circuit two times but it not work OK.
    Big noise and a great coupling with out pot near maximum and before near maximum too.
    I have tried 1n4148 diodes, instead bat41. MI
    I have tried with bc337-25, instead 2n5089.
    What is the problem?