Two rock reverb question

[paisley_tele]

On the custom reverb sig it had one reverb knob but on the
Classic reverb there's a send and return for reverb. I think that like a mix and dwell control right? If how what needs to be changed too have a two knob reverb. Is it the resistor the comes off the RCA to ground?

[glasman]

On the custom reverb sig it had one reverb knob but on the
Classic reverb there's a send and return for reverb. I think that like a mix and dwell control right? If how what needs to be changed too have a two knob reverb. Is it the resistor the comes off the RCA to ground?

Odds are that the Reverb is being fed to the driver tube via a 470 to 500pf cap with a 1Meg to ground on the grid of the driver.

To make a dwell control you would need to remove the 1M resistor and replace it with a 1M potentiomenter with the wiper feeding the grid of the tube.

Gary