I would like to remotely trigger a switch to change the routing of an audio amplifier's output to different speakers. I have a 2 channel amp, and by default, one channel powers the Left & Right speaker, and the other powers a subwoofer. I'd like the option to switch it so the Left and Right speakers are each powered by their own channel, and the sub gets disconnected. This would give me the choice between mono w/sub or stereo without. This is in an auditorium, with the amp rack up in a room a distance from the sound booth. (There is a DSP unit receiving the audio mixer's L,R,Sub outputs and I can write separate programs for it and change them remotely via an app or RS-232, so the changes I'd need to make on my input signal are all set.) I have extra unused line-level audio cables running between the two locations and I figured I could use one of them to send a small latching or control voltage down to change the state of the switch circuit from the sound booth. With my limited knowledge, I'm just thinking I'd need something like a DPDT latching relay (I'd rather not have to maintain a voltage full-time to keep it at a particular state. Am I in the right ballpark as far as methodology? Also, I'm wondering if I'd need to keep the negative of each speaker isolated? For most things you could probably tie the common together but I'm wondering if the amp is pushing out two separate differential signals without respect to a common reference? I've never seen speaker negatives tied together so I'm thinking I'd need a 4PDT relay? Is there a simple solid state way to handle this? These are very high power pro audio speakers so we're talking a decent amount of current. I've attached a diagram to illustrate.
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