Bar, What Is It Good For?
Why a soundbar? It's an unfussy solution to what has become a nearly universal flaw in ever-flatter flat-panel TVs: lousy sound. The thinner a TV enclosure gets, the harder it becomes to build good speakers and amps into it. The growth of soundbars is not so much a fad as a necessity. After all, we have ears as well as eyes, and when we're watching a movie, we like having both senses competently entertained at the same time.
Pros & cons: The upside of soundbars is that they're easy to install and (usually) to use. Most will let you get by without the often challenging complexity of a surround receiver. Good reproduction of voices is not unknown. The downsides: Tuneful, forceful, and well integrated bass is harder to find, even with a supplementary subwoofer. And soundstage width is limited to the bar's physical width. Some products (like the Phase Technology Teatro TSB3.0 pictured above) use side drivers and/or psychoacoustic trickery to push the left and right channels a little farther apart, but the laws of physics can bend only so much. Soundbars typically support surround channels flimsily if at all.
Three kinds of connectivity: I know the word connectivity makes your eyes glaze over, but stay with me here, because you need to make a connectivity decision before you buy a soundbar. A soundbar connects to your source components in three ways: through the TV, through the bar itself, or through a receiver. The implications may be profound. Many bars are designed to accept a single analog or digital (usually Toslink) connection from the TV itself. Thus the TV serves as the system switcher, mediating between your cable box, DVR, etc. and the bar. Most bars can also accept source-component connections directly—but usually only audio connections, so you'd still switch video through the TV. The gain in performance rarely trumps the reduction in convenience. Finally, a few passive bars (usually with two or three channels worth of drivers) accept speaker-level input from a receiver. They are basically two or three satellite speakers, sometimes with drivers of high quality, built into a single enclosure. Once again, the Phase Tech bar above is an example of this. This is the way to go if you want your system to have a full roster of receiver-borne features, surround channels, and a subwoofer that's not a joke.
Active vs. passive: Most soundbars are active, meaning they have onboard amplification. The reason to go with a passive soundbar would be for use in a receiver-based system. That would allow you to use real (discrete) surround speakers. An even bigger advantage is that you could have the sub of your choice. It's not hard to improve on the ones packaged with most soundbars.
Number of channels: Soundbars may have (nominally) two, three, five, or seven channels, (typically) with or (occasionally) without a sub. The greater the number of channels, the greater likelihood of psychoacoustic fakery, though there are a few bars that can simulate surround rather craftily. Under ideal conditions, anyway. Most bars purporting to have a full 5.1-channel array can also function in two- or 2.1-channel mode, and with some content they might even sound better that way. If you really want a high-quality 5.1+ system, and a lot more features and flexibility (and complexity) you should consider moving one step up the foodchain, from a soundbar to a compact satellite/subwoofer speaker system fed by a proper surround receiver.
HDMI vs. legacy connectors: Most soundbars have no pretensions about offering the latest and greatest technology. They have a combination of stereo analog inputs and digital (usually Toslink) inputs. If the bar is an inexpensive product connecting through the TV, that's fine. But some bars do have serious HDMI connectivity, which is now standard equipment on any respectable TV or receiver. HDMI is a better option if you want the highest-quality lossless surround formats. The presence of HDMI does not guarantee higher performance but it may signify higher aspirations.
Flavors of surround: Soundbars may have no surround decoding, fake surround decoding, limited surround decoding, or entirely up-to-date surround decoding. Those with no decoding include all passive bars and lower-end active ones. Fake surround decoding typically adapts incoming stereo signals to surround. It may be well done or not. Limited surround decoding is usually old-school Dolby Digital, often though not invariably accompanied by old-school DTS, generally entering the bar through a Toslink input. Up-to-date surround decoding includes all of the above plus lossless DTS-HD Master Audio and Dolby TrueHD decoding, generally entering the bar through HDMI, and possibly other digital-ins with certain limitations. No self-respecting receiver would omit HDMI and lossless surround. If you want your bar to deliver a higher percentage of the home theater experience, consider the fully equipped step-up models.
Wireless connectivity: Quite a few soundbars connect wirelessly to their cheap subs. While this theoretically allows greater flexibility in sub placement, the small subs included in soundbar packages usually operate at a high crossover, which means they have to stay close to the bar in the often desperate hope of achieving a good blend. The other form of wireless connectivity in many bars is Bluetooth, so you can play tunes from your smartphone or tablet. And now, a few words from our self-promoting author...
Please forgive me for plugging my own project, but my book Practical Home Theater: A Guide to Video and Audio Systems (2014 Edition) will go live in a few weeks. This will be the 13th edition (and no, I'm not superstitious). It is the only book on the subject to receive annual updates. As with previous editions, its life cycle will run from October of this year to October of next year. I always kill the old edition as soon as the new one is ready for individual ordering and on-demand printing. However, beware of old stock: The most foolproof way to get the latest edition is to click through directly from the Quiet River Press website to Amazon and other retailers, look for the cool hunter-green cover, and make sure you're getting ISBN 9781932732153 (the ISBN changes with every edition). PHT 2014 should be available just in time to capture your holiday-shopping dollars. I'm sneaky that way.