3PDT Switch Popping

[overdrive]

If you've got your 1M5 pulldown resistors properly in place, a beefier resistor on the LED + a ground wire on your 3PDT & there is still an audible pop when activating the effect, is this simply par for the course or is there some sort of microphonics going on from within the 3PDT switch itself?

It's not so much of an explosive-sounding pop but rather a somewhat detectible muffled pop exclusive of the typical & audible mechanical sound that the switch ordinarily makes when turning it on.

Funny thing is that out of 5 fxs only one (an Orange Squeezer) seems to be making this sound.

[pdf64]

Confirm that there's no Vdc (leaking out from the fx coupling caps). Pete.

[Mark Hammer]

This IS a different source/sort of popping than most of us are used to dealing with. The OS would seem to be one of those devices that presumes to use SPDT switching, and is designed around it. I gather it has something to do with the charging of electrolytics that are part of the rectifier and attenuation circuit. They need to remain charged up, and do so by always seeing audio signal, whether the circuit's audio output goes anywhere or not. I had a great deal of difficulty with mine until I reverted from true-bypass to simply switching between the circuit output and the input jack, just like they did when the product line first came out.

So revert back to SPDT switching of the audio signal (which means you can use a DPDT for LED + audio) and see if that makes a difference for you.

[overdrive]

The diffused LED was the culprit. Had to incorporate the inline AMZ 4K7 resistor/10uf capacitor delay to eliminate the pop. LED is slightly dimmer now but no big deal.