I have a Denon X3200W and two BK Gemini subs. The AVR has two sub outputs (RCA) though I think that they are just connected internally. The subs each have two low level inputs (RCA) labelled right / mono and left. So, I can use a mono RCA cable from the AVR to the sub's right socket and leave the left socket empty. However, I wonder whether the empty socket might pick up noise. I see a few choices:
1. Forget the issue, I am worrying about nothing.
2. Connect a shorted RCA cable to the empty socket to force a zero signal.
3. Use a Y cable so that both inputs are connected to the AVR. A slight concern here is that the AVR would get the load of four inputs when it only expected two. For a high level output, I would be cautious but, at this level, I don't expect a problem.
1. Forget the issue, I am worrying about nothing.
2. Connect a shorted RCA cable to the empty socket to force a zero signal.
3. Use a Y cable so that both inputs are connected to the AVR. A slight concern here is that the AVR would get the load of four inputs when it only expected two. For a high level output, I would be cautious but, at this level, I don't expect a problem.