Depending on the model, there are two ways to connect a subwoofer to an amplifier, receiver or processor. The best way is to connect the subwoofer to the SUB OUT or LFE output of a receiver, but some subwoofers can be connected to the speaker level outputs of the receiver or amplifier.
1. How to Connect a Subwoofer to the Subwoofer Output
The preferred method of connecting a subwoofer is through the LFE or Subwoofer output (SUB OUT) of a receiver. Almost all home theater receivers (or processors) and some stereo receivers have a subwoofer output. The LFE (Low Frequency Effects) is a special output for subwoofers and is often labeled 'SUBWOOFER' not LFE. 5.1 channel programs on DVD discs have a dedicated .1 channel output with bass-only content that is best reproduced by a subwoofer. Connect the output of the LFE or Subwoofer jack to the Line In jacks of the subwoofer using a single RCA cable (the two jacks on the left in the photo). A 'Y-Cable' may be necessary to connect the LFE output to both the left and right channels of the subwoofer.