Stop the Pop

[Govmnt_Lacky]

Wanting to build up a flanger project where I have switchable "Manual" controls. Since the pot is acting as a voltage divider and is responsible for controlling a DC voltage... Is there any way to switch between 2 pots (while the pedal is still on) WITHOUT getting the dreaded POP?

[PRR]

Don't listen to DC control voltages.

[Govmnt_Lacky]

Don't listen to DC control voltages.

Thanks!

Anything constructive?

[GibsonGM]

   Keep it out of your signal path entirely.   So you aren't 'listening' to it.

Control a vactrol or something...depends on where the DC control voltage is going/what it's doing, right?
Like a 'wireless wah pot', maybe you can isolate that part of the circuit so your "Manual" controls aren't vulnerable to the changing level when switching...

[Govmnt_Lacky]

I want to put a Flanger manual control onto a wah pot but, I want to make it switchable on the fly. Since the Manual pot has voltage going through it, I assume that mechanical switching between two pots will cause the usual POP.

I have read about others trying to use caps to help isolate or control the popping to no avail. Was wondering if anyone found a solution.

[GGBB]

This *might* work:

Assuming a typical voltage divider setup for a pot connected Vin-Vctrl-gnd on pins 3, 2, 1:

Vin to VR1pin3 and DPDTsw1a
DPDTsw1c (common) to VR1wiper and VR2pin3
DPDTsw1b to VR2wiper and Vctrl out
VR1pin1 to DPDTsw2b
VR2pin1 to DPDTsw2a
DPDTsw2c to ground

Pots are partially in series with VR1 wiper connected to VR2 pin 3. Control voltage output is connected to VR2 wiper. Both pots' pin 1s are grounded/lifted through the switch.

What this does (if I described it right):

In the first position, the switch grounds pin 1 of the first pot and lifts the pin1 ground of the second pot, and jumpers the second pot from pin3 to wiper, thereby connecting the control voltage output to the wiper of the first pot - i.e. the first pot is a complete voltage divider and the second pot has control voltage applied to pin 3 and wiper (shorted) but pin 1 is lifted.

In the second position, the switch grounds pin 1 of the second pot and lifts the pin1 ground of the first pot, and jumpers the first pot from pin3 to wiper, thereby connecting the control voltage output to the wiper of the second pot - i.e. the second pot is a complete voltage divider and the first pot has control voltage applied to pin 3 and wiper (shorted) but pin 1 is lifted.

This prevents breaking the voltage flow from Vin to the control voltage output, but it does break the ground connections of the dividers. So it might work well enough, don't know. It might help to put a huge resistor from Vin to ground across this as well as a huge cap to ground from the voltage control output.

[PRR]

I really think your "dread" is premature.

Do it. Try it.

Changing control voltages WILL cause a sudden change in the system. Whether this is "the dreaded POP" or a strange flange side-step is implementation specific. Due to past sins, I have way too much experience switching pitch control voltages. We just switched them. Pop was not a problem.