Why can't I get my stereo effect to work?
99% of the time when we see this issue its because there is a mono effect in loop A and a stereo effect in loop B
The problem with this set up is with the RETURN A. If you were just using a mono signal path this would be fine, the reverb signal on the ‘tip’ RETURN B (mono plug = ground/shield & tip) would mix on top of the mono signal on the tip of RETURN A.
The issue is that you’re feeding RETURN B with a stereo signal (this is tip-left, ring-right, and ground/shield) and feeding through to the stereo mixer, to the stereo outputs.
So the RING part of the TRS cable has the other part of the stereo signal, BUT, if LOOP A uses a standard mono cable, then the RING part of the return of LOOP A is connected directly to ground, so you won’t get any signal from LOOP A to the stereo output.
The solve is to use a cable like this on the return of loop A