All audio experts agree that two subwoofers are better than one. With the fervor of a Star Wars nut explaining the Force, they'll tell you how using two subs makes bass response smoother for multiple listeners. But don't worry; it's easy to get the experts to clam up -- just ask them for an easy way to fine-tune the performance of two subs.

Optimizing one sub for one listening position is a piece of cake. Put the sub in your favorite listening chair, play some music or test tones with a wide variety of bass notes, crawl around the floor until you find the spot where the bass sounds the most even, and install the sub in that spot.

But with two subs, all bets are off. Well, some bets are off. If you have a rectangular room, you can get great results by putting the subs in the front corners of the room, or centered on opposite walls. Who has a rectangular room, though? In a real (i.e., non-rectangular) room, achieving ideal bass response means equalizing one or both subwoofers - which usually means taking lots of measurements, making lots of adjustments, and knowing what you're doing in the first place.

Finally, a subwoofer maker has created a way to double without trouble. Velodyne's SC-602 houses two 200-watt digital amplifiers that power two separate subwoofers. The amp incorporates an automatic five-band equalizer to correct for the effects of room modes. Simply hook up the subs and amp; put the included calibration mic in your listening position; and hold the EQ button on the remote control for a few seconds. The amp automatically emits test tones, measures the level of these tones through the microphone, and adjusts itself accordingly.