Overview of 2.0, 2.1, 5.1, 6.1, 7.1 Channel Systems

How many channels do you need for your home stereo system?

Along with speakers, receivers constitute the core of most home stereo or theater systems. Given the number of options available — channels in particular — one might be left wondering which to choose. It really all comes down to the kind of content you plan on enjoying and the level of realism you wish to experience. Acquiring additional speakers to support a multi-channel receiver doesn't have to be expensive if you stick to a plan and a budget. So here's the breakdown of what all the extra channels really mean.

2.0 and 2.1 Channel Stereo Systems

A living room designed with the look and feel of a plush movie theater
Dana Hoff / Getty Images

Your basic stereo system (2.0) consists of two channels of sound — left and right — produced by a pair of stereo speakers. Most speakers are powered by a receiver (or even a good amplifier), although more modern ones can bypass the need for such equipment through extra features and/or wireless connectivity. A 2.1 channel system is achieved as soon as you incorporate a separate subwoofer (the .1 part of surround sound) along with the stereo speakers. The benefit of choosing a 2.0 or 2.1 channel system is affordable simplicity. You can enjoy excellent audio for music, movies, and TV without the clutter of additional speakers and the wires that tend to come with them. But if a truer surround sound experience is what you're after, you'll want more than just one pair of speakers.

5.1 Channel Home Theater Systems

Home theater receivers are distinguished from two-channel (stereo receivers) by having additional amplifier channels to support movie theater sound (e.g. Dolby Digital 5.1, DTS 5.1) or multi-channel music (e.g. DVD-Audio, SACD discs). Your basic home theater system offers 5.1 channels of sound through five separate speakers and one subwoofer. Like a two-channel system, the left and right speakers create that sense of direction and play most of the on-screen action. The center speaker is typically reserved for movie dialog, music vocals, and supporting sounds. The left and right surround/rear channels help to give that immersive dimension of space by playing off-screen surround sound and special effects. The subwoofer channel (also known as Low-Frequency Effects, or LFE) adds very low bass for music sources and special effects on soundtracks. Together, all of the channels produce a "soundfield" that envelops the listener with sound coming from the front and behind.

6.1 Channel Home Theater Systems

All that a 6.1 channel system offers over a 5.1 system is one more speaker. With the addition of the rear-center, you end up with three speakers in front, two as surround, and then one dedicated at the rear (plus the subwoofer). To some, this extra speaker may not be worth the money, space, and effort to install. But if you want to experience greater realism, this rear-center speaker helps to create more precise positioning and imaging of sound. Moving sound effects, such as passing vehicles, voices, or bullets whizzing overhead, will seem far more real and defined with a 6.1 channel system. However, you have to make sure that the source content has been encoded to support this type of playback (e.g. Dolby Digital EX, DTS-ES).

7.1 Channel Home Theater Systems

Similar to how the 6.1 steps up from a 5.1 channel system, a 7.1 channel receiver adds another speaker into the mix. So you'll have three front channels, two surround channels, and then two rear channels (plus the subwoofer). So does this extra, rear speaker make a significant impact on sound placement and surround effects? The answer might depend on how much you enjoy that convincing, movie-like experience in your own home. Many 7.1 channel receivers offer THX ​soundfield enhancement. Developed by Lucas Film and optimized for movies and multi-channel music, THX processing is designed to present movie/music sound with the most authentic quality. You may also come across other (proprietary) soundfield programs, such as Sony's Digital Cinema Sound or Yamaha's Cinema DSP. Although it can be a challenge to position and wire up a 7.1 channel system, the results will be worth it for those who want nothing less than the best.

Was this page helpful?