Howdy,

Recently finished off a KoT-ish thing, and it works perfectly but has absolutely horrendous switch pop - but ONLY for the order switcher.



Each half of the pedal has WIMA coupling caps before a 1M pulldown on the input/output. I am GUESSING if it was something coming from either half of the circuit I'd notice it switching each side on/off, but with that it is absolutely dead-nuts quiet - it is just the order switching that is causing problems.

I have the 3k9/100p on each sides input because I have absolutely HORRENDOUS RF noise as I live at the base of a tower - on most pedals it's 10/100p but I figured with two I'd dial it back a bit.

If I had to hazard a guess, could it be something to do with the indicator LED for the order causing problems? If not, what do you suggest is worth trying? I was thinking about just adding pulldowns on the 4PDT directly (just ran out of time before work to try today).

Thanks!

There is a difference in switching times for the separate poles of a 3PDT or 4PDT switch and this difference in timing is randomly distributed and is within the audio frequency range.  This is how a pedal can go through extensive development and show little switching noise and then the production units show excessive noise.

If you want noiseless switching, check out the switching designs in this thread:

https://www.diystompboxes.com/smfforum/index.php?topic=120006.msg1122294#msg1122294

Threw pulldowns over the output jack and both the order-ins.

Probably 90% gone, which is good enough for government work