How to Buy an Integrated Home Theater Audio System

The Big Picture

An integrated home theater audio system, or home theater in a box (often abbreviated as HTiB), includes all the equipment you need to add surround sound to your TV or video system. Some systems are more elaborate than others, and some include significant additional features, such as built-in DVD players. The basic elements, however, are these:

• Speakers for at least five channels of audio--left and right front speakers, two surround and one center
• An amplifier to drive the speakers
• A control center that connects to your video sources--DVD player, TV, digital video recorder, and the like--and decodes the multichannel audio signals from DVDs, TV programs, and so forth for delivery to your speakers. For many people, a standard home theater receiver can do double duty as a control center and an amplifier.

Prices range from a few hundred dollars for extremely low-end systems to several thousand for the most ambitious. Systems with good overall performance, sound quality, and bass typically start at around $500.

Speakers

Systems typically include five to seven relatively small satellite speakers plus a considerably larger bass module, or subwoofer, which reproduces most of the low frequencies.

The satellites break down into three functional categories: center, front left and right, and surround. The center speaker goes directly above or below the TV screen (usually right on top of the set). Front left and right satellites are placed at the sides of the screen, at equal distances from it. Although the two main surround speakers are often called "rear speakers," they really should be positioned just slightly behind and along the sides of the seating area whenever practical. (An extremely bare-bones system might include just a single surround speaker for placement at the back of the room, but this is rare nowadays.) Many systems use identical satellites for all locations, while others may have somewhat different speakers for the center or the surrounds. The center may be designed specifically for horizontal placement, for example. What's important is that their tonal character be the same.

The subwoofer can usually be placed just about anywhere that's convenient, though its sound will vary somewhat depending on its placement and the acoustical characteristics of the room. Design details, such as whether the subwoofer cabinet is sealed or ported (which means there is a hole or vent in the box), are seldom a significant shopping consideration. Be aware, however, that it is harder to get strong deep bass from a small box than from a large one. That doesn't mean you have to buy a huge subwoofer to get good sound, but don't expect miracles from a tiny one.

That's it for a standard 5.1-channel setup (five plus the bass-only ".1" channel handled by the subwoofer). Some systems provide one or two additional back-surround speakers for 6.1- or 7.1-channel operation. These additional back-surround speakers should be positioned behind the seating area.

One other category, which has grown over the last few years, comprises systems that use special virtual-surround circuitry or speaker configurations to approximate the sound of a multispeaker installation from a single pair, or even a single box, at the front of the room. Obviously, this is a lot more convenient than running wire all over the room to feed surround speakers at the sides or back. And the best of these systems do a surprisingly good job. However, none of them perform as well as a good multispeaker setup. Always listen to such a system before you buy, paying attention to the quality of the sound off to the side as well as directly in front of the speakers.

Amplifiers

An amplifier strengthens audio signals enough to drive the loudspeakers. A system's amplifiers may be built into the individual speakers, into the subwoofer (in which case all the satellites connect to the subwoofer), or into the control center that contains the surround decoder. When a manufacturer creates a system by packaging a regular audio/video receiver with a set of speakers, the amplifiers for the satellites will normally be in the receiver and the amplifier for the subwoofer in the subwoofer itself. Any of these configurations can work very well, and there is no reason to prefer one over the other in terms of performance.

Control Center

The system hub is a control center that provides surround-sound decoding, volume control, and other basic functions. (Often it will be a standard audio/video receiver.) An extremely simple unit might provide just one set of audio inputs, for connection to the audio outputs on a TV set. Most, however, provide multiple inputs and the ability to switch between them using a remote control.

In a system with Dolby Digital decoding capability, at least one input will be digital. Dolby Digital is the standard audio format for DVD and HDTV, so this capability is highly desirable. At minimum, you should expect Dolby Pro Logic or Pro Logic II decoding, which will work with just about any surround-encoded soundtrack you encounter. (Since devices such as DVD players, which are designed for Dolby Digital, provide Pro Logic-compatible analog outputs as well, you will not be left out in the cold, although the quality of the surround will be somewhat lower.)

Many control centers provide video as well as audio switching. That allows you, for example, to connect the audio and video outputs from a DVD player and a VCR to the control center, and connect its audio and video outputs to one set of inputs on the TV, with all switching done through the control center. Some also have built-in DVD players for watching DVDs and listening to CDs.

Choosing a System

• Speakers first. Speakers affect sound quality more than any other part of a system. So try to listen to a system before you buy. All else being equal, a system from a company that specializes in loudspeakers is likely to have better speakers than one from a company known primarily for its electronics.
• Think digital. For the best possible surround sound from DVDs, make sure the system provides Dolby Digital decoding.
• Check your inputs and outputs. Make sure you have all the inputs and outputs necessary to accommodate whatever equipment you expect to route through the controller. For example, if you want to connect audio and video from a progressive-scan DVD player, look for component-video inputs. Another potential "gotcha" involves digital audio connections, which come in two flavors--optical and coaxial. Be sure you can match the types of digital inputs and outputs on the devices you want to connect.

Pay attention to the speakers and a handful of details, and it's hard to go wrong.