Subwoofer Serenades

Here are the tracks I rely on when evaluating subwoofers. There aren't a lot of them, but there shouldn't be - you should know every nuance of your reference tracks, and having too many only makes it harder to remember what to listen for. Pick a music track and a film scene you know well, and use them for every sub you audition.

A good subwoofer will produce clean, spacious, enveloping bass. Using a jazz recording of an acoustic bass will provide a good sense of whether the notes sound natural. Two-channel playback will give you a better idea than multichannel playback of how good a sub is because you'll be able to hear more clearly how it's blending with the main speakers. You shouldn't think of subwoofer evaluation as "music vs. home theater" anyway, because a sub 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. - T.N.

CDs • 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. • The Great Fantasy and Adventure Album (Telarc) At 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 Erotica, Bass Ecstasy (Neurodisc) Listen in particular for the strong, isolated fundamental bass tone at 22 Hz in "976-BASS." If a sub can't reproduce it cleanly, it's time to move on to the next one.

DVDs • U-571 (Universal) Check out the depth-charge scenes about 2 minutes in and again in Chapter 15, and listen for the strong low-frequency aftershocks that follow the explosions. 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. • Godzilla (Columbia TriStar) There's plenty of deep-bass action throughout, but the main menu just keeps looping through the room-rumbling 25-Hz monster stomps until you make a selection. • DVD Space Spectacular (Delos) The start of Thus Spake Zarathustra (Chapter 1) has deep, powerful organ notes and a thunderous climax. Set your player for repeat, and you can keep looping this segment to your heart's desire.