The Setup: Speakers Page 3

Next, optimize the distance between the speakers and the wall behind them, which will always involve a tradeoff. Locating speakers closer to a wall will increase their effective bass response but degrade imaging and spaciousness. Keep in mind as you experiment that nothing you do is going to yield killer bass from a bass-shy speaker or room-filling 3-D spaciousness from speakers that can't provide that kind of performance under any circumstances.

Because tonal balance will suffer if you place the speakers in an area of bass cancellation or reinforcement, you'll probably have to experiment with their distances from the walls to find the best compromise between tonal accuracy and bass punch. Tip: Keep notes and make temporary marks on the floor with masking tape. You might want to go back to an earlier position if a later one sounds worse.

Next, adjust the toe-in, or the degree to which the speakers are angled in toward the listening position. Exotic dipole speakers, such as planar magnetics or electrostatics, or bipole speakers that have separate drivers firing both forward and backward, are sometimes best placed parallel to the wall behind them - that is, with no toe-in. With conventional direct-radiating dynamic speakers, start by aiming them toward the listening position, and then experiment with different angles until the instrumental and vocal imaging and the soundstage depth and width all seem to "lock in."

It's a good idea to enlist a friend as a second pair of ears during the adjustment process. And if at any time you start to feel confused or fatigued, stop and resume the setup when you're mentally refreshed.

Now for some final tweaking. Sometimes tilting the speakers up slightly will improve imaging and tonal balance - but make sure that they're still secure on their bases or stands, not rocking precariously. Many speakers and speaker stands come with spiked or conical feet that can be easily adjusted for height. These pointy protuberances might improve imaging and bass definition slightly by helping stabilize the speaker cabinet. (Install them after you've determined the final location for the speakers.) If your speakers or stands don't have adjustable feet, you can place thin pieces of wood under the front corners.If you're using adjustable-height feet or stands, set them so the tweeters are at ear level when you're sitting in your listening position.

For 6.1-channel listening, set up one or two additional speakers along the rear wall, at the same height as the left and right surround speakers. Aim dipoles so the driver sides fire to the left and right along the wall (as shown at left). Direct-radiating surround speakers (not shown) should be aimed so they fire toward the front of the room.

I Think We're Surrounded! If you're setting up a stereo music system, you can stop now and enjoy listening to your favorite CDs as never before - in fact, the improvements will likely be so dramatic, it'll be as if you're hearing them for the first time! But if you want to set up a six-speaker 5.1-channel system, or a seven- or eight-speaker 6.1-channel system, read on.

As noted, many of the principles that apply to stereo speaker setup also hold true for the left and right front speakers in a multichannel system. However, there are three additional considerations: 1)You might have to move these speakers away from their "ideal" positions to make room for the TV or projection screen. 2) Many home theater installations mount the front speakers on the wall behind the TV, or along with the TV if it's a flat-panel or built-in model, making it impossible to move them out into the room as recommended above. Nevertheless, the front speakers should still be mounted with the tweeters at ear level, positioned far enough apart for a good stereo spread, and aimed toward the listening position for the best sound coverage. 3) The optimal position for the left and right speakers is relative to that of the center-channel speaker.

Since it handles most of the dialogue and up to 60% of the other sonic information in a movie soundtrack, the center-channel speaker is the most critical part of a home-theater speaker system. While different manufacturers recommend slightly different setups, a good rule of thumb is to mount the center speaker atop the TV, slightly behind the front L/R speakers (assuming they're not wall-mounted) and no more than 2 feet above or below their tweeters. Some manufacturers recommend placing the left, center, and right front speakers in an arc, with all three equidistant from the listening position.