Setting up a Home Theater

Setting up a Home Theater

Although pleasing the eyes with a first-rate picture is a critical part of creating a good home theater setup, it could all be for naught if the sound can't keep up. While it's true that today's televisions are vastly better than their predecessors when it comes to audio quality, even the best can't come close to delivering a true theatrical experience. It's a pretty big commitment -- both in time and money -- to set up a surround-sound home theater system, and there are a few things you need to know before you get started.

Surround-sound basics

Creating a proper surround-sound field requires a minimum of five speakers placed in specific locations at recommended heights relative to your seating position. In addition, unless you are using large, full-range speakers, a powered subwoofer is recommended to reproduce the rumbling, ultra-low bass that's a big part of Hollywood action films.

By contrast, a television's integrated sound system typically consists of two speakers. Most deliver stereo sound and many use signal processing to create a virtual surround-sound effect. But while virtual surround sound sometimes does a satisfactory job of creating a surround field, the effect varies greatly with the program material and room acoustics, and it can't compete with a surround field created with a proper home theater speaker setup. That means the best home theater sound must be achieved by using lots of speakers (and lots of wire). If you are interested in reading more about speaker placement, About.com has an excellent primer.

You'll see surround-sound systems labeled as 5.1, 6.1 or 7.1. That designation refers to the number of sound channels. For example, a 5.1 system will have five speakers -- right front, center front, left front, right rear surround and left rear surround -- plus a subwoofer (that's the .1). Surround-sound systems designated as 6.1 or 7.1 add one or two rear-center surround channels to the mix.

Home theater speaker systems are marketed in two ways. Some are sold as complete systems, consisting of four to six satellite speakers, a center-channel speaker and usually a subwoofer. Others, particularly higher-end surround-sound systems, are sold as individual components. The latter option lets users configure the system to meet their particular needs, yet be assured that the components are well matched sonically to produce a balanced and realistic surround-sound field.

Surround-sound formats

A home theater also needs some type of home theater receiver or amplifier to drive the speakers. Most receivers are compatible with some or all of the latest sound formats -- technology that specifies how sound from TV shows and DVDs is delivered through the speakers. Dolby and DTS are the two major players.

Every surround-sound receiver or amp includes some type of Dolby surround-sound processing, and many support multiple formats. Dolby Digital is the most popular surround-sound format and is used in HDTV programming and most DVDs. It contains 5.1 channels of sound information. Dolby Digital EX adds an additional rear-center surround channel to create an even more realistic surround-sound field. It can be implemented with either a single center-rear surround speaker (6.1 channels) or twin center-rear surround speakers (7.1 channels).

Surround-sound receivers also often include Dolby Pro Logic processing. Pro Logic takes an existing audio mix and derives additional channels to create a more expansive surround-sound effect. The original Dolby Pro Logic II produced 5.1 channels of sound from a stereo audio source. Dolby Pro Logic IIx expands stereo and 5.1 audio to 6.1 or 7.1 channels. Dolby Pro Logic IIz is the latest variation. It adds a height channel to 5.1 or 7.1 audio to produce an even more enveloping surround-sound field, though setting that up will require a system with up to nine speakers plus a subwoofer. Only a handful of the latest receivers include Dolby Pro Logic IIz processing.

Most surround-sound receivers and amps also support some type of DTS surround sound. DTS Digital Surround is a 5.1 surround system, while DTS-ES outputs 6.1 channels of sound. All DTS-equipped home theater receivers also support DTS Neo:6, which creates six-channel surround sound from material originally recorded in stereo. Some receivers support DTS 96/24, which is sound recorded at a higher sampling rate than normal for what's said to be superior audio quality.

For those with a Blu-ray player, Blu-ray Discs typically feature lossless or high-definition surround-sound formats, either Dolby TrueHD or DTS-HD Master Audio. Depending on the disc, these will deliver 5.1-, 6.1- or 7.1-channel sound. Some Blu-ray Discs also offer uncompressed, unprocessed pulse code modulated (PCM) audio, which can be sent via HDMI to some of the latest home-theater receivers.

Home theater systems and sound bars

Complete home theater systems, which typically include a receiver and DVD player or Blu-ray player -- either separately or as one integrated component (along with all the speakers you need) -- are also available. Most offer good value, are relatively easy to set up and some are excellent performers. On the down side, experts say you can usually get better sound quality and more flexibility by purchasing the speakers, receiver and disc player separately.

Speaker set-up considerations are the same as if you purchased the speakers separately. Most home theater systems also include decoders for the major Dolby and DTS surround formats, and some include decoders for Dolby TrueHD and DTS-HD Master Audio.

Sound bars offer the ultimate in convenience for those looking for better sound with a minimum of fuss. These sleek boxes are designed to be placed under a wall-mounted TV or beneath a stand-mounted TV. Most look good, and there's no bother with running speaker wires all around a room. Sound bars either come with all of the electronics built in -- including a disc player in some cases -- or need a separate amplifier.

Sound bars do have some shortcomings. Bass response is one -- not a surprise given a sound bar's typical small profile -- but some sound bars either come with a powered subwoofer or allow one to be added. As is the case with built-in TV sound, the technology sound bars use to create a virtual surround-sound field has its limitations. Still, if style, easy setup and improved sound are more important than hearing a bullet whizzing by your head during an action flick, sound bars could be worth considering.