Digital Trends

The center channel loudspeaker is the most important one in any surround system. Failure to use it properly is holding back the development of surround sound as a music medium. It's not the only thing inhibiting music in surround—record-company apathy and stereo's dominance in downloads are bigger problems. But it worries me that a listener getting his first taste of music in a 5.1-channel format might not hear it at its best.

Why is the center so crucial? Doesn't that seem counterintuitive? After all, stereo systems get along without any center channel at all. However, movie mixes depend heavily on the center channel to deliver both dialogue and the leading edge of those action-movie surround effects that make our hearts beat faster. That's why many speaker makers design the center with a higher efficiency rating—they know it needs to play loud.

In music, as well as movies, the center channel serves a second function—to fill that hole in the middle that undercuts the soundstage in stereo (or in quad for that matter). True, high-end two-channel gear set up in a good room by someone who knows what he's doing can produce swooningly realistic imaging. But how often does that happen in the real world?

All other things being equal, it's better to have a center-channel speaker than not to have one. Besides lending greater clarity to dialogue and lead singers, it also produces a seamless front soundstage that anchors the soundfield. That becomes a major advantage in any kind of music playback, whether you're listening to a 5.1-channel DVD-Audio or SACD release, or playing your CDs in the 5.1-channel Dolby Pro Logic II music mode.

DPLII is a relatively new surround format that I can't praise highly enough. Not only does it derive center, surround, and subwoofer channels from two-channel sources like CDs and LPs—it actually does the job well. In better surround gear offering the full array of DPLII adjustments, you can alter the balance between the center and sides, either concentrating sound in the center or redistributing it toward the left and right. You can also adjust the front-to-back balance. All this can be done without messing with the overall channel levels in the speaker setup menu.

If I listened to nothing but DPLII-enhanced CDs I'd be well content. It's the high-res DVD-Audio and SACD releases in my listening diet that worry me. Too many multi-channel music mixes either underuse the center channel or don't use it at all.