Microphonic fuzz pedal?

[jm22]

I am planning to try my hand at making a fuzz pedal or two, but I'm still in my learning phase and have some general questions. I have six fuzz pedals at the moment, and one of them is quite microphonic. If you tap on the housing, it makes a sound similar to what you get when you tap on an un-potted microphonic guitar pickup. I don't find it objectionable, but I'm still curious as to what is the exact source of the microphonics. The pedal is apparently a copy of the Mossrite Fuzzrite.

So my questions are, are microphonic fuzz pedals common? When they do occur, is the cause always the same? And which exact components are likely the cause?

[amptramp]

Solid-state components should not be microphonic.  Ceramic capacitors can be microphonic  But if you don't have either of those, solder connections can be microphonic.  If your board is not mounted securely, it can touch the chassis and cause momentary microphonic sounds.  I don't see anything suspicious in the picture, so solder connections that are dry or loose would be my first guess and secure the board to the chassis.

[EBK]

You could fire it up and gently tap on each component, wire, and solder joint with the eraser end of a pencil (really, you could use anything you want as a tapping tool).  Should be able to find the problem.

[jm22]

Thanks for the replies. I'll try tapping on the individual components. It sounds like this is fairly uncommon.

[duck_arse]

a signal carrying wire that is allowed to move might get some microphonics going.