HOME ELECTRONICS : Decoders Can Be the Best Value to Upgrade Theaters

Today’s electronic sound decoders take the Dolby stereo audio signal present on many laser discs and videotapes and split it into four separate channels of sound--left, center, right and surround--to produce an audio effect known as surround sound. When the separate channels of sound are routed to strategically located speakers, they can turn a living room into a home theater.

According to Video Magazine, decoders can offer the most for your money in upgrading a home theater environment. While most modern audio-visual receivers have decoders built in, stand-alone units are also available with added features such as integral amplifiers, switching devices and the ability to include extra surround modes for playing music. These range from $300 to $3,000.

What you pay for in the higher priced decoders is mainly added features. Almost all good decoders are Dolby Pro-Logic, which, through the use of a special chip, decode the Dolby Stereo signal. The latest versions of the Dolby chip will outperform earlier chips in the most expensive decoders. Even the least expensive Pro-Logic decoders are so good that the quality of your home theater need not depend on an expensive decoder. An investment in quality speakers and support equipment is a better idea than putting a lot of money into a sophisticated decoder.

The least expensive stand-alone decoder tested by the Video Magazine editors--the Kenwood SS-992 listing for $299 and with the actual price closer to half that--furnished sound and separation good enough to satisfy all but the most critical home theater enthusiasts.

The Kenwood has its drawbacks, however. It doesn’t have a remote control, making it necessary to adjust volume at the set. It also doesn’t do as well with straight music CDs, especially of the rock variety, because it tends to thin out voices.

Higher priced decoders may require an expert to decode the features. The $1,500 model tested, the Lexicon CP-1, came with a 60-page owner’s manual that might be just the thing for a hi-fi technology expert but confusing for a novice.