Audiophiles know that a stereo is not complete until you've added a subwoofer to your system. The subwoofer is a speaker specifically designed to give precise sound to low frequency audio, such as the bass [source: Nicholls]. Whether in your car or your home theatre, a subwoofer is a must for a true and complete audio experience. Read the steps listed below and learn about how to connect a subwoofer to an amplifier.

  1. Turn the amplifier and the subwoofer so the backs are facing you. You will be able to clearly and accurately see the labels on top of the outputs and plugs.
  2. Locate the plug on your amplifier that is labeled Sub Out, LFE (low frequency effects) Out or Line Out [source: KEF].This is the terminal used to connect the subwoofer to the amplifier.
  3. Connect the cable that was included with the subwoofer to the amplifier's terminal. Alternatively, you can connect an RCA cable that can be purchased at any electronics store [source: KEF].
  4. Connect the other end of the cable to the terminal on the back of the subwoofer marked Line In [source: Nicholls].
  5. Insert an audio disc that has deep bass sounds and press play. Human ears are the best devices for gauging whether your subwoofer is set up properly. Set the phase control on the amplifier to zero and the output to minimum. Throughout the song, adjust the levels until you're satisfied with the amount of bass coming out of your subwoofer [source: Nicholls].