Carbon Black Fuzz Top control

HamishR

Well-known member
I'll admit that I built mine on vero, not the PCB. I have checked my Vero design against the schematic many times and I'm sure it's ok - it's a simple circuit after all. I think I will build my next one on the PCB because I really like this fuzz. BUT: on mine the Top control doesn't do all that much to the highs but does seem to affect the bias of one of the transistors, and I quite like the effect! Below noon the knob adds a crackle and very slight gating which adds a cool colour to the sound. Above noon it's a clearer, rounder sound and a pretty good Tonebender tone. I like the amount of gain, ie not super saturated but quite nasty sounding.

My question to anyone who has built one - do you have the same experience? I'm using some ancient looking 2N3903s and it sounds great. I'm wondering if the bias-sounding effect is intentional or an accident with mine.
 
The top control is a simple passive LPF that should be decoupled from the Q3 bias trimmer. If you’re getting interaction there, I’d imagine that you have a short, the 100nF cap was omitted, or the top pot is wired somehow as a voltage divider feeding the Q3 collector.
 
Back
Top