B-Side Fuzz hiss

[sticky1138]

I'm getting a high pitched whistle from this build, which increases with the treble and gain controls. I'd expect some noise from a high gain fuzz, but not like this.

I thought maybe it was a bad opamp, but I tried six different JRC4558s and then a couple TL072s with no avail. Anyone else experienced this?

 

[kylewetton]

Did you find a solution for this?

 

[Bricksnbeatles]

I had the circuit on my breadboard for the past week with pretty much no extraneous noise, and that’s usually much more susceptible to noise than a boxed up build on a PCB. The fact that turning gain or treble up makes it more prominent makes sense— rsising the treble is increasing the volume of high frequencies, your noise included, and the gain is of course boosting the levels of everything. Perhaps it’s power supply noise? Try hooking it up with a battery (via a battery-to-2.1mm adapter, or with alligator leads) to see if that fixes it. If it does, check out your power filtering caps. Maybe there’s solder bridging them or you have too small of a value by accident. Could just be a noisy power supply. What’s the frequency of the whine?

 

[Harry Klippton]

My build does not whine either

 

[sticky1138]

Tried multiple power supplies with no change.

I noticed the Aion version of the Demo Tape has a slightly different schematic with a 10p cap and omitted 100n. I bought that one on a whim and it works hiss free, then I made those changes to the PPCB circuit and it didn't make a difference, hiss-wise.

I might be imagining it, but the PPCB version sounds better than the Aion. Good to hear someone got it to work without hiss because this is one kick-ass pedal.