You typically have two options when connecting a powered sub woofer. Input (1) on the rear of the sub woofer would be used when connecting the sub woofer to the receiver using speaker wires. You would then connect the main speakers to the opposite end, or output or the sub woofer to the main speakers. Option (2) would be using RCA line level output jacks, input (2) on the rear panel of the sub woofer directly to the single sub woofer output on the back of an AV receiver.
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