Subwoofer Reviews

The first time I attended the Las Vegas Consumer Electronics Show, in January 1986, I didn't get there until the second day of the Show. Still, by the beginning of the fourth and final day I'd managed to visit every high-end audio exhibit, and still had time to go back for seconds to the rooms that had sounded the best. Twenty years later, CES has grown so much that it's impossible for a single writer to visit even a quarter of the exhibits in which he might be interested. And even with the sort of team reporting Stereophile now practices, covering the Show has become an exercise in applied logistics for the busy journalist: "Should I wait for the free shuttle bus? Should I get a taxi—though I might get caught in Las Vegas's increasing traffic jams, or even just get stuck at the city's interminable traffic lights? Or should I take the new monorail—though that goes nowhere near the hotel in which [insert name of hot company] is demming its products?"

Home theater has dramatically influenced the design of aftermarket subwoofers. Multichannel processors automatically provide a properly filtered low-frequency signal to drive a subwoofer, relieving the need for the sub to be shipped with a passive crossover network or an active electronic crossover. When Genelec offered one of their subwoofers for review, I decided it was important to try to evaluate such a product, even if it meant I'd have to scramble around to find a quality external electronic crossover.

It didn't seem like such a big deal. After all, when designer Kevin Voecks added a passive radiator to the bottom of Revel Loudspeakers' powerful Ultima Sub 15 subwoofer, no one expected that the resulting 6dB increase in bass output below 35Hz would be so audible. However, Revel's sophisticated double-blind listening tests (described in my review of their flagship Ultima Salon full-range loudspeaker in the March 1999 Stereophile, revealed that a big change had occurred. With now twice the radiating surface, the modified Sub 15 produced significantly deeper, more powerful bass.

Harry Partch (1901-1974), composer and inventor of musical instruments, delighted in generating deep bass. Finding most standard orchestral instruments wanting in that department, he built the huge Marimba Eroica, which he described on his A Glimpse into the World of Harry Partch: 27 Unique Instruments (LP, Columbia MS-20576):

It's common to read ads for new audio hardware that crow about "revolutionary" breakthroughs in sound performance, and that's how Velodyne crowed about their new Digital Drive DD-18, servo-controlled, powered 18" subwoofer. The ads suggested that the DD-18 can be digitally equalized to one's room with a resultant in-room frequency response of 20-200Hz, ±3dB.

From The Audio Catechism:
Q: What is a subwoofer?
A: A large, ugly device that must be placed in the most inconvenient location in the listening room—for instance, in front of the only door.
Q: What is the purpose of the subwoofer?
A: To produce prodigious amounts of low-frequency sound and to glorify its owner, who can rest safe in the knowledge that his is the biggest.