Eliminating switch pop - for good

[lars]

I've found that this true-bypass switch wiring scheme is 100% effective in eliminating switch pop, even in pedals where no other traditional method has worked:



This is a typical input-grounded true-bypass wiring scheme, but it also grounds the board output through a 470K resistor when bypassed. The beauty of this setup is that the 470K resistor goes nowhere when the effect is on, since the ground leg is lifted (so it does not constantly have an affect on the circuit like a typical pull-down resistor does). This wiring effectively eliminated a nasty pop in a reverb pedal I built. I also used this recently on a fuzz pedal that had a minimal pop, and it eliminated it. I think this is a much better option than the 1Meg (or higher) resistors that are usually added to circuits.

[Aleph Null]

I've got a popping effect that a 5M input pull-down resistor didn't cure. I'll have to give this a try and report back.

[TNblueshawk]

I've build a lot of pedals over the years and some pop more than others. I've always wanted to go back and fix them but I've just been lazy. This is very helpful and might push me to do it and see how it works.

[lars]

One thing to mention is that any existing pull-down resistors you might have in the circuit should be removed in addition to trying this wiring scheme. The pedals I've been able to get this to work on do not have any pull-down resistors. I really hope this works for people...I know how frustrating switch pop can be.

[Scottosan]

Am I missing something?  i see no schematic or layout

[HamSandwich]

Postimg is down, replace the org with cc or your pictures won't post.

[sjaustin]

Interesting. I have a couple boxes I'm gonna open up as soon as I'm off work...