Unrelated question:
If the subwoofer system has just one speaker and your amp has a "single, mono" subwoofer output, do you really need to use both the left and right subwoofer inputs if so equipped? I would think connecting to just one of the jacks is just fine.
I suppose a monaural-stereo cable can be used anywhere you would want a Y-connector for two audio signals to funnel into one amp input, or one audio signal to split off to two amps or preamps.
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