OTHER TECH

Here are some CDs and DVDs you can use to evaluate subwoofers in stores, to set up and test the one you choose, or to scare your neighbors. Pick out a couple and listen to a few tracks over and over. It'll drive your wife crazy, but trust me, it's a lot easier to hear the differences between subs by playing a few tracks you know well than by playing a lot of different material.

A good sub will produce clean, spacious, enveloping bass. A first-rate jazz recording of an acoustic bass is probably the best way to see if bass notes sound natural. And you should evaluate subs using two channels rather than surround sound - it'll give you a better sense of how the sub is blending with the main speakers. But don't think of this as "music vs. home theater." A subwoofer doesn't care if it's being fed a freight train, a synthesizer, a bass drum, artillery fire, a standup bass, or a pipe organ. It's all acoustic energy, and what matters is whether it sounds right.

CDs

• Bass Erotica, Bass Ecstasy (Neurodisc) Listen for the strong, isolated fundamental bass tone at 22 Hz in "976-BASS." If a sub can't reproduce it cleanly, move on to the next one.

• The Great Fantasy and Adventure Album (Telarc) About 12 seconds into "Jurassic Lunch," listen for the T. Rex footfalls, which go all the way down to 10 Hz. With a good sub, the subsequent attack will leave both you and your house seriously shaken.

• Bass Connection, Drivin' Bass (Neurodisc) The first track, "Pure and Perfect Bass," is very loud and goes very low. In fact, the infrasonic content is so strong that you should use this cut with caution.

• Johnny Cash, American Recordings (Universal) "Bird on a Wire" will tell you how a sub handles male voices, which fall into the upper end of a sub's range. If the level is set too high or the sub isn't properly balanced with the main speakers, Cash's baritone voice will sound unnaturally strong.

DVD & D-VHS

• The Matrix Reloaded (DVD, Warner Bros.) Chapter 15 is filled with lots of low bass being pounded out at high sound-pressure levels. Small sounds, like the tomato squish near the beginning and the voices, shouldn't be masked by the bass.

• U-571 (D-VHS, Universal) Listen for the strong low-frequency aftershocks that follow the explosions during the depth-charge scene about two minutes in and again in Chapter 15. Also listen to the quieter scenes that follow. The low-frequency background sounds should be evident without intruding on the voices and other foreground sounds

• DVD Space Spectacular (DVD, Delos) The beginning of Thus Spake Zarathustra (Chapter 1) has a deep, powerful organ note and a thunderous climax. Set your player for repeat, and keep looping this segment until you've got your sub sounding just right.

• The Lion King 1/2 (DVD, Walt Disney) When rocks are slid at the very beginning of Chapter 2, you'll hear two "swells" that contain lots of very deep bass. On a good sub, this will come across as the actual sound of a rock sliding and not just noise. The second swell is the more demanding of the two.

• Godzilla (DVD, Columbia TriStar) There's plenty of deep bass throughout, but the main menu just keeps looping through the room-rumbling 25-Hz monster stomps until you make a selection.