Author Topic: Eliminating switch pop - for good  (Read 2303 times)

lars

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Eliminating switch pop - for good
« on: April 04, 2018, 08:19:11 PM »
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.
« Last Edit: April 14, 2018, 07:07:36 PM by lars »
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Aleph Null

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Re: Eliminating switch pop - for good
« Reply #1 on: April 05, 2018, 12:49:30 PM »
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

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Re: Eliminating switch pop - for good
« Reply #2 on: April 05, 2018, 01:04:33 PM »
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.
John

lars

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Re: Eliminating switch pop - for good
« Reply #3 on: April 05, 2018, 11:15:49 PM »
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.
« Last Edit: April 05, 2018, 11:18:09 PM by lars »
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Scottosan

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Re: Eliminating switch pop - for good
« Reply #4 on: April 13, 2018, 09:25:55 AM »
Am I missing something?  i see no schematic or layout

HamSandwich

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Re: Eliminating switch pop - for good
« Reply #5 on: April 13, 2018, 09:37:20 AM »



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

sjaustin

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Re: Eliminating switch pop - for good
« Reply #6 on: April 13, 2018, 09:45:11 AM »
Interesting. I have a couple boxes I'm gonna open up as soon as I'm off work…