Connect Using the LFE Subwoofer Output
The preferred method of connecting a subwoofer is through the subwoofer output (labeled SUB OUT or SUBWOOFER) of a receiver using an LFE (Low-Frequency Effects) cable. Almost all home theater receivers and processors and some stereo receivers have this type of subwoofer output. Surround sound audio (also known as 5.1 channel audio) such as media found on DVDs or cable television, has a dedicated channel output with bass-only content that is best reproduced by a subwoofer. Setting this up requires connecting the LFE or subwoofer output jack on the receiver/amplifier to the LINE IN or LFE IN jack on the subwoofer. It’s usually just one cable with single RCA connectors on both ends.
Connect Using Stereo RCA or Speaker Level Outputs
Sometimes a receiver or amplifier does not have the LFE subwoofer output, and sometimes the subwoofer doesn’t have the LFE input. Instead, the subwoofer might have right and left (R and L) stereo RCA connectors or spring clips like you see on the back of standard speakers. If the subwoofer’s LINE IN uses RCA cables and the subwoofer out on the receiver/amplifier also uses RCA, plug it in using an RCA cable. If the cable is split on one end (a y-cable for both right and left channels), plug it in the R and L ports on the subwoofer. If the receiver/amplifier also has left and right RCA plugs for subwoofer output, be sure to also plug in both to the receiver. If the subwoofer features spring clips for speaker wire, use the receiver’s speaker output to hook it all up. This process is the same as connecting a basic stereo speaker using speaker wire. Be sure to mind the channels. If the subwoofer has two sets of spring clips (for speaker in and speaker out), it means that other speakers connect to the subwoofer, which then connects to the receiver to pass along the audio signal. If the subwoofer has only one set of spring clips, the subwoofer must share the same receiver connections as the speakers. The best way to accomplish this is by using banana clips that can plug into the backs of each other rather than overlapping bare wire.