Surround sound comes in many flavors, from 5.1 channels up to 32 speakers for immersive 3D audio. The key to great results is placement.
1. Surround-sound speaker systems typically contain five or more speakers and one or more subwoofers. Currently, most movies come with a 5.1 or 7.1 soundtrack; any additional channels are fed with derived signals from the AVR or preamp/processor. (This is not true with immersive soundtracks and speaker systems; all speakers are fed native signals in that case.)
2. The tweeters of the front speakers should be at seated-ear height; use stands with bookshelf-style speakers to place them at the correct height. Make sure you measure carefully when installing in-wall or on-wall speakers.
3. Place standard surround speakers two feet above ear level. For a 5.1 setup, the surrounds should go on the side walls, slightly behind the listening position. In a 7.1 system, the rear surrounds go on the back wall.
4. For flat-panel TVs and acoustically opaque projection screens, place the front left and right speakers within a foot or two of the sides of the screen. The center speaker goes directly above or below the screen—it should go above the screen if you have more than one row of seats.
5. With an acoustically transparent (AT) screen, place the left, center, and right speakers behind the screen, with the left and right as close to the edges of the screen as possible and the center in the middle. If you use a perforated AT screen (as opposed to woven), you also need have enough room to place the speakers about 12 inches behind the screen.
6. Subwoofer placement is tricky. Putting a sub in a corner increases overall levels but may sound boomy. Placing it at the half or quarter point along a wall often results in tighter and more even bass.
7. Using more than one subwoofer can help even out bass response from one seat to the next. This also offers more output compared with using a single sub.
8. Immersive-sound formats such as Dolby Atmos, Auro 3D, and DTS:X create a 3D soundfield using height channels, which requires additional speakers. For example, Trinnov’s Altitude32 processor supports 32 speakers, but most current AVRs with immersive capabilities max out at 9 or 11 speakers.
9. DTS:X and Auro 3D recommend placing the height speakers above the main speakers at an elevation of roughly 45° and 30°, respectively. Dolby Atmos suggests placing the height speakers in the ceiling or using special Atmos-enabled speakers.
10. Dolby Atmos-enabled speakers and modules reflect sound from the ceiling to create a sense of height and immersion. However, they require a flat and acoustically reflective ceiling—no higher than 14 feet—for the effect to work well.