OUR TEST SETUP Any subjective evaluation of subwoofer performance is as much a review of the room as it is of the sub. At about 350 square feet and 3,000 cubic feet, my studio is similar to many family rooms, except it's double-sheetrocked and built to dimensions I chose for achieving reasonable low-end smoothness and extension. As in any speaker evaluation, you can expect the same sub to perform differently in a different room.

From long experience, I know that subs deliver their smoothest 20- to 100-Hz response in my room when placed behind the left front speaker. Our three bantams were small enough that I could set them up cheek by jowl and switch among them for fair comparisons - as I verified using a sound-level meter to calibrate volumes and check positions.

I ran all three in crossover-bypass mode, setting my preamp's crossover at the THX-standard 80 Hz. And to simplify things, I did my listening using short segments of music tracks and movie scenes that I'm very familiar with (see "Test Tracks" below). My colleague Tom Nousaine also measured each sub's performance (see "In the Lab," as well as the individual reviews).-D.K

TEST TRACKS CDs

• James Taylor, Hourglass (Sony), "Line 'Em Up" This track has probably the strongest bass guitar you'll hear on a pop recording. It's a six-string bass that occasionally hits low Cs down at about 32 Hz. The sound, which is rich and heavy through the range from 30 to 120 Hz, is occasionally quite powerful.
• Janet Jackson, The Velvet Rope (Virgin), "Go Deep" I'm no great hip-pop fan (though I like Miss J's album art), but this track is a bass classic. It features rock-steady synth bass at around 35 Hz, with a couple of forays into super-low 25-Hz country.

DVDs Movies can demonstrate a different side of bass, since the low-end sounds are usually more fleeting and more likely to be masked by higher-frequency sound effects and music.

• U-571 (Universal), Chapter 15 The famous depth-charge attack produces powerful and dynamic bass with content well below 25 Hz. Listen to your sub alone and crank this segment up to hear what your woofer's working life is really like.
• The Fifth Element (Columbia/TriStar), Chapter 2 Another valued clip for deep, deep bass is the moment in the movie's prologue when the stone chamber closes with a rumble. This is a good source of sustained bass that extends just about as deep as U-571's depth charges.