If your current receiver has no subwoofer (RCA) line level output, you will need to connect the subwoofer to your receiver using speaker wire connections on the rear of the receiver. You first need to take the speaker input from the subwoofer to the A or B speaker terminals on the rear of the AV receiver. Then take the speaker outputs from the sub woofer and connect to the main speaker terminals inputs. In essence, you will be connecting from the AV receiver to the sub woofer, then from the sub woofer to the main/rear speakers.
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