What Each Speaker Does in a Home Theater
Before placing speakers in a surround sound setup, you need to know what each one does.
Left/right channel speakers: These speakers output most of the music and sound effects in a movie or TV soundtrack. They also provide a way for sound effects or dialogue coming from the front of the listening area to move from left-to-right or right-to-left. When listening to stereo music, the L/R channel speakers operate the same way as in a two-channel stereo system. Center channel speaker: The center channel speaker anchors dialogue or music vocals. The vocals and dialogue still appear to come from a center position if you move your seating position from left to right. In most cases, the center channel speaker volume can be adjusted separately from the L/R channel speakers if the dialogue is too low or too loud. Subwoofer: The subwoofer reproduces only the lowest bass frequencies, such as a bass drum, an electric or acoustic bass, explosions, and other low-frequency effects (LFE). The subwoofer may only be active when the soundtrack needs to provide the listener with low-frequency sound effects. Surround speakers: Surround speakers supplement the front L/R speakers. The surround speakers reproduce sound or ambiance effects that provide a fuller, more immersive listening experience. Surround speakers may be positioned to the side, back, and above the listener, depending on the surround sound format.
Speaker Setup Options
There are general loudspeaker position guidelines that can be followed as a starting point. For most basic installations, these guidelines will be sufficient. The following examples are provided for a typical square or slightly rectangular room. You may need to adjust the placement to other room shapes, types of speakers, and additional acoustical factors.
5.1 Channel Speaker Placement
Here’s the optimal setup for a 5.1 channel system:
Front center channel speaker: Place the front center channel speaker directly in front of the listening area, either above or below the television, video display, or projection screen. Subwoofer: Place the subwoofer to the left or right of the television. Left and right main/front speakers: Place the left and right main/front speakers equidistant from the front center channel speaker, about a 30-degree angle from the center channel. Left and right surround speakers: Place the left and right surround speakers to the left and right side, to the side, or slightly behind the listening position—about 90 to 110 degrees from the center channel. These speakers can be elevated above the listener.
6.1 Channel Speaker Placement
In this setup, the front center and left/right main speakers and subwoofer are the same as in a 5.1 channel configuration.
Left and right surround speakers: Place the left and right surround speakers to the left and right side of the listening position, in line with or slightly behind the listening position about 90 to 110 degrees from the center. These speakers can be elevated above the listener.Rear center channel speaker: Place directly behind the listening position, in line with the front center speaker. This speaker may be elevated.
7.1 Channel Speaker Placement
In this setup, the front center and left/right main speakers and subwoofer are the same as a 5.1 or 6.1 channel setup.
Left and right surround speakers: Place the left and right surround speakers to the left and right side of the listening position, in line with or slightly behind the listening position—about 90 to 110 degrees from the center. These speakers can be elevated above the listener.Rear/back surround speakers: Place the rear/back surround speakers behind the listening position, slightly to the left and right (may be elevated above listener) at about 140 to 150 degrees from the front center channel speaker. Rear/back channel surround speakers can be elevated above the listening position.
9.1 Channel Speaker Placement
This setup uses the same front, surround, rear/back surround speaker, and subwoofer setup as in a 7.1 channel system. However, additional front left and right height speakers are placed about three to six feet above the front left and right main speakers directed toward the listening position.
Dolby Atmos, DTS:X, and Auro 3D Audio Speaker Placement
In addition to the 5.1, 7.1, and 9.1 channel speaker setups, there are immersive surround sound formats that require a different approach to speaker placement.
Dolby Atmos
For Dolby Atmos, instead of 5.1, 7.1, and 9.1, there are new designations, such as 5.1.2, 7.1.2, 7.1.4, and 9.1.4.
Speakers laid in a horizontal plane (left/right front, center, and surrounds) are the first number.The subwoofer is the second number (may be .1 or .2)The ceiling-mounted or vertical drivers represent the last number (usually .2 or .4).
For additional illustrations on how the speakers can be placed, go to the official Dolby Atmos Speaker Setup page.
Auro 3D Audio
Auro3D Audio employs a 5.1 speaker layout as a foundation (referred to as the lower layer). However, it adds an additional height layer of speakers slightly above the 5.1 channel lower layer speaker layout (five speakers above each speaker in the lower layer). An additional top height layer consisting of a single speaker/channel is positioned directly overhead (in the ceiling). This speaker is referred to as the Voice of God channel. The VOG is designed to seal the immersive sound cocoon. The entire setup consists of 11 speaker channels, plus one subwoofer channel (11.1). Auro3D can also be adapted to a 10.1 channel configuration (with the center height channel but without the VOG channel) or a 9.1 channel configuration (without the top and center height channel speakers).
