As a young music lover, I never knew there were such things as separate preamplifiers, amplifiers, and FM tuners. All I knew was that if I wanted to play music from my CD player, hook up my VCR to my stereo, or listen to the radio, I needed that magical device: a receiver. It was all I ever wanted.

Subwoofer technology is moving fast, with automated room equalization and system integration now a reality. A wave of new products has appeared in the past five years, all using different approaches to solving the problems of optimizing subwoofer response in listening rooms.