Microphonic enclosures ?

[danielzink]

Hey all,

I seem to be having an "issue" lately with microphonics......(well...only two so far......but still an issue for me).

One build from scratch pedal (an OD) that seems to be exceptionally bad. I can hear everything that goes on - inserting the plugs into the jacks, heck - I can even hear the spring inside the 3PDT switch !

I don't know if it's a coincidence or not - but I've also started using solid core wire lately. Would this increase the possiblity of microphonics ? just grasping at straws here.

Thanks, Dan

[runmikeyrun]

anything can pick up the microphonics, any components including the switch.  I swear I had a microphonic jack one time too- replaced it and it stopped doing the same things yours is doing.  Take the circuit out of the enclosure and try tapping around on components with a chopstick and see if you can reproduce it.  Try it bypassed first and tap on your wires in the bypass circuit, switch, and jack.  If that checks out ok, switch it on and check the rest of the circuit.  If it's a fuzz turn the gain and volume all the way up (turn your amp down!) and that will help you hear it more clearly. 

If you think something is suspect, either take it out of the circuit and bypass it with alligator clips (if it's a passive component like a switch or wire) or with another of the same part.  Be warned though- if you use components from the same package there's always the possibility they're a bad run, but it's small.  Anyhow, replace parts one at a time until you find the problem.  Start with the big, easy to replace/bypass stuff first before you start unsoldering.  And make sure you tap on those wires if you think that's the problem.

[R.G.]

ceramic capacitors are made from much the same materials that "crystal" phono cartridges used to be and that piezo transducers are. They are microphonic many times.

Any mechanical vibrations can be transmitted to them.