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You can either run your amplifier connections to the main speakers and then run another set of speaker cables to the subwoofer. Alternatively, you can either wire from the amplifier to the subwoofer and then jump off to your main speakers, or vice versa. You can go to the speakers from the amplifier and then from the main left and right speakers, and jumper to the subwoofer. In any case, connect both the left and right speaker outputs wherever they’re coming from to the input of the subwoofer amp.