Unlike the front three speakers, that must produce sharply focused images, the job of surround channels is to envelop the audience in diffused sound known as "ambience." To excel at this job, rear speakers should not call attention to themselves as sources of sound. For these reasons, surround speakers work best when elevated at least two feet above the seated listeners' heads (a height of six to seven feet above the ground is considered normal), and mounted on the side walls in line with or slightly behind the audience. If you are using front-firing speakers, they should face each other so that the sound is projected over the listeners' heads.

If your seating area adjoins the rear wall, or if you cannot place speakers on the side wall, you'll have to position the speakers on the rear wall. In this case, we recommend bi-directional (bi or di-pole) speakers, since they will produce the most diffuse effect. If you use front-firing speakers, do not aim them at the audience as one would a front speaker, but point them straight forward so the sound projects past the audience. Another option is to mount in-wall speakers in the ceiling, slightly behind the listening area.