Footswitch Pop

I’m getting some footswitch pop on my reverb now that I have most of the other problems licked.  I’m using a “half” true-bypass to allow the reverb to trail of naturally instead of cutting off abruptly with the footswitch.  I’ve not seen much on the Google about achieving “trails” (or “tails”) with reverb or echo units.  I see where people are attempting to implement it, claim it works, then take it out because it’s not working.  Of all the schematics I’ve found, none are too clear about the switching circuit itself.  Most schematics leave the switching out completely so it’s hard to know exactly what’s happening.  But I’ll leave that to another post.

I already have a pull down resistor at the input of my circuit.  The theory is that any DC bias that tries to feed the input will be pushed to ground through this resistor.  There is also a capacitor in series with the input buffer that blocks DC.  One problem arises when the capacitor is initially charged.  When the circuit is bypassed, the capacitor is empty.  When the circuit is engaged, that cap sucks in current until it fills to capacity, at which time it becomes a DC blocker.  This sudden rush causes an audible pop due to the voltage potential differential.

Another cause of pop can be the LED that tells the user the effects circuit is on.  This happens because of the change in voltage potential???

Leaky capacitors can also cause a voltage potential difference that gives pop.

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