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SEPARATES ARE BETTER
As we mentioned previously, you can buy a generic all-in-one home theater system. Ultimately, however, most people tire of the less than stellar performance - particularly that of the speakers - sooner than they thought they would. And when you want to upgrade or add capabilities, these "home theater in a box" systems are severely disadvantaged. That's why we suggest separate components as a more intelligent way to go. In addition to substantially better performance, individual components allow you to upgrade or add to your system on a step-by-step basis to better protect your investment and to keep you at the forefront of enjoyment. All component systems include sources - a satellite converter, DVD player, cable box, VCR, etc. - that let you access a program, a movie, or a music recording of some sort. For many people, the next component is a receiver, a single unit that includes connections for all your sources, switching capability so you can watch and listen to the source you want, a built-in AM and FM tuner so you can hear your favorite radio broadcasts, very sophisticated digital signal processing (often abbreviated DSP), to decode the various surround sound formats (more about them in a page or two), and, finally, a multi-channel power amplifier to provide the power you need to get all of your speakers into the act when you need them. If that sounds like a lot of "stuff" going on in one box you're right! In fact, a receiver is probably the single most complex piece of equipment in any home theater system. But receivers are very convenient space-savers and a number of people choose one for just this reason. The. good news here is that receivers can provide excel- lent performance. The not-quite-so-good news is that, once again, your upgrade or add-on potential is limited simply because a receiver includes everything so changing anything means a new receiver! There is an answer to this dilemma - the "full separates" approach. This replaces a receiver with a surround processor/preamplifier, a power amplifier, and, if you want one, a tuner. Not only do these individual components provide even better performance than a receiver can, particularly in the power amplifier department, they also allow you to tailor a system precisely to your needs. As for future upgrades, separate components provide the easiest way by far to improve your system. WHAT YOU'LL NEED - THE SURROUND PROCESSOR The nerve-center of your home theater, the surround processor connects everything in your system. Sources (DVD and CD players, VCRs, satellite and cable boxes, etc.) plug into the processor to deliver both audio and video information, some of it analog in nature, some digital. Most of the time, the digital signals are encoded in some way. Although you have the option of telling the processor what to do with each signal, some more advanced models figure things out on their own and decode signals automatically. Once your processor decodes the signal you've selected, it routes images to your TV, and sends the audio portion on to your amplifier and, once there, to your speakers. Many processors let you select different sources to be sent to different areas of your home. Most also give you ways to modify or enhance the audio portion of the signal in some way to make it more pleasing or more enjoyable to you. You should know that many processors convert even analog audio signals to digital before they send them through the active circuitry. (Digital signals are left as digital.) After the processor performs all necessary decoding, a digital-to-analog conversion stage then transitions the signal back to analog so an amplifier can use it. Video signals, on the other hand, most often remain analog all the way from source to display. (In case you are wondering, DVD players put out an analog video signal even though the information on the disc itself is digital.) WHAT TO LOOK FOR 1.) Inputs and Outputs: Make a list of everything you're going to watch and listen to through your new home theater system. Remember to include familiar sources like AM and FM broadcasts, cassette decks, etc. Then think of the newer digital sources. Maybe you have two or more CD players, a satellite TV box and are thinking about satellite radio in the near future. Then there's cable TV, maybe a video game or two, a computer link or Internet connection. Once you've listed everything you can think of, add another just to be safe. Then look for a processor with enough inputs to handle sources you'II be enjoying. Then think about outputs. Will you be routing audio and video to more than one room? What kind of TV will you be using and will it have connections for the best picture? Most of the processor's outputs, at least those for audio and video signals, will use RCA connectors. You'll need to know just a bit about the different connectors some source components use to get the signals to your processor. And your processor, in turn, will send different kinds of signals to other components. All this is really simple when your dealer or installer helps you sort things out. In the meantime, here are the most common types of connectors you'll see. Video We've already shown you the various types of video connectors. Look on "The Video Side of Home Theater - Composite, S-, and Component Video Signals" page for a quick refresher. Remote Control Consider how you're going to "talk" to the processor Will you use a hand-held remote controller? Will your processor be used as part of a computer-controlled "whole house" system? If so, some processors provide a computer-style terminal to make that connection easy. Will your processor need to send "wake up" signals to amplifiers that might be located some distance away? If so, a number of processors can do that, too. Relax. If this seems a bit intimidating, don't worry. Again, your dealer or installer will take care of these details for you. But it doesn't hurt to begin doing a little homework here to help the process along. 2.) Surround Sound Formats: This is probably the most confusing thing about home theater systems. That's because there are now eight different formats, each claiming different advantages. Here they are: Dolby Pro Logic, Dolby Pro Logic II, Dolby Digital, Dolby Digital EX, DTS, DTS ES, DTS ES Discrete, and DTS Neo:6. As you can see, both Dolby and DTS have several entrants in the Surround Olympics. Here's a quick overview of these formats
WHAT'S IMPORTANT There's a lot of discussion (putting it mildly) about the sound quality of various surround sound formats. We think you'll be very happy with what you're going to hear from any of them providing your system is properly set up and calibrated. That's something your dealer or installer will be glad to help you with. You should know, however, that roughly 10,000 DVDs are now available, all Dolby Digital encoded. Almost 2,000 of these carry a full "5.1" soundtrack. Compare that to the roughly 200 DVDs encoded with other surround formats. THE POWER AMPLIFIER If the processor is the nerve center of your home theater system, the power amplifier is its taskmaster. It controls the single most important component of your system - the loudspeaker. Speakers do not just passively accept an amplifier's signal. In fact, they resist it. To complicate things further, speakers exhibit other characteristics that make it difficult to control. They even generate a signal that returns to the amplifier! So how does an amplifier function properly under these conditions? Well, the simple answer is that some don't. Some amplifiers are actually unstable when pushed and severely distort the signal. In extreme cases, an amplifier can literally destroy itself attempting to deliver a signal to a particularly difficult speaker. The answer to these problems lie in the balance between an amplifier's output stage and its power supply. If the power supply is the beginning of an amplifier's ultimate capability, it is the output stage that delivers this potential to "real world" loudspeakers. Good power supplies, however, are expensive to build. They ensure that an amplifier can deliver adequate power as each channel - or all of them at once - ask for it. An inadequate supply simply results in distortion, sometimes very severe distortion. What should you look for in an amplifier? First is the ability to drive all of your speakers to levels you are comfortable with. In other words, does an amplifier have enough power and can it deliver its claimed output into many speakers at once? For some, especially those who live in apartments, power output requirements are comparatively modest. For others, those who insist on experiencing the full power of an earthquake in a large room, power needs will be far more substantial. Unfortunately, you're in a particularly difficult position to judge what's enough. That's because most manufacturers rate amplifier power output capabilities differently and "spec comparison" is almost impossible.
Here are some things to look for:
The point here, obviously, is that you need to be careful when comparing amplifier specifications. Here's something to remember: A manufacturer who gives you all the information you need to make an informed decision is probably the manufacturer who spends the time designing good products in the first place. ◄ ► |
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