Tone cap switching and ground referencing

[wizard333]

I'm experimenting with using push/pull pots to switch in different tone caps. On one, a separate cap is switched in to be in parallel with the existing cap, in another, a cap is switched in to be in series. Eg.: Switching a .001uf treble cap in parallel with the existing cap; switching in a .022uf mid cap in series with the existing cap.

I think I should be ground referencing the side of these caps that is usually "open", i.e. not switched in, although I'm not getting any significant "pop", anyone have a suggestion on R value that will provide a useful drain for the cap but not affect the tone circuit aurally? I don't want to go so big that there is no useful drain for the cap, but also not so small that it starts to have a noticeable affect on the tone of the circuit.

[Enzo]

If it ain't broke, don't fix it. if you are not getting pops, then don't bother adding things to fight pops.

Keep in mind the point is to keep the caps charged to whatever the circuit demands. So that is not automatically a reference to ground. Many times the cap switched is in parallel to something that is grounded, and then we do indeed reference to ground. But if your cap is betweeen two points in a circuit not grounded, then don't. A 1meg is my default anti-pop resistor. I put it across the open switch, not to ground, unless the switch goes to ground. Reference the thing to the other side of the switch, not necessarily ground.

[wizard333]

Wasn't doing it just for pops; something "didnt sound right" once I put the switches in, and I was getting the old wandering DCR readings.

Sounds ok referenced to ground, I ended up using 2.2M, but I can see your point about referencing the other side of the switch instead. Is there an advantage to doing that? Will it sound different or does it avoid problems that might be created by referencing ground?

Thanks!

[Enzo]

A 1 meg resistor should effectively remove the part from the circuit, at least functionally.

I don't know what the circuit is, so I can;t comment on grounding stuff. I am only addressing the question about preventing pops. Sticking a high value resistor from most places in a circuit won't have much effect on it in general. The advantage to wiring a rsistor across the switch is that it keeps the cap charged. A resistor to ground may or may not do that depending upon whatever the circuit might be.

[wizard333]

Makes sense to me, I'll try it. Thanks!