[sdiy] easiest ringmod circuit for multiple inputs/nulling??

[Paul Perry]

If the inputs have different amounts of DC offset, then you will get
different amounts of carrier bleed.
If you are able to send the various sources through caps, and the output end
of the cap is grounded via say a 100K resistor so that it stays at an
average of 0V, then you should be OK as you switch from one to another.

And, yes, the PCB will be better than a breadboard.
But even so, a ring modulator is a very hard thing to make perfect.
Some people cheat & have a noise gate to cut out the bleed during silent
parts.. but I find careful layout & decoupling the carrier oscillator (I use
a couple of 220 ohm resistors in the power rails, plus filter caps before
and agter them.)

Paul perry Melbourne Austrlaia (Frostwave)