We already have a big-screen television, and my children want a home theater sound system. I saw some rated at 600 and 800 watts, which would be expensive to operate. How do I select one?
Both a big-screen, high-definition television and a surround-sound home theater system can draw quite a bit of electricity, but not as much as you might think. The size of the television is not a good indicator of its operating costs. Its design is more important.
The wattage rating you see on the packaging for a home theater system is the sum of the sound output from the speakers. A system with six 100-watt speakers will be listed as a 600-watt system. If you look at the main power supply specifications, some may draw as little as 200 watts of electricity to produce that much sound. A powered subwoofer speaker will use a little more.
At an electric rate of 9 cents per kilowatt hour, installing a surround sound home theater system that uses 200 watts will cost about 2 cents per hour of use. It is wise to switch off the power when the movie is over to save a little more electricity from the sound system.
Since the cost to operate one is relatively low, most experts recommend buying the most powerful system (speaker wattage) you can afford, up to about 100 watts per channel. Above this, your children may crank it up and drive you out of the house. Higher-wattage speakers on a low setting generally have less sound distortion than lower-wattage ones turned up.
You can choose among several sound formats for your home theater. Dolby digital is most commonly used on DVD movies. It offers five distinct channels of sound plus a subwoofer for low-frequency effects. The subwoofer is a large speaker that makes you "feel" a train go by in the movie.
Standard Dolby digital is often referred to as "5.1" for the five speakers and one subwoofer. A receiver (tuner/amplifier) control unit decodes audio information on the DVD movie into the five-plus-one channels of sound.
The next step up is Dolby Digital EX, which is 6.1, with an extra rear speaker. A competing sound format is DTS, but not as many DVDs and games use this.
Unless you understand audio equipment, it is best to buy a "home theater in a box." These are complete systems that include all the matched speakers, color-coded wiring and a receiver control unit. The most difficult part of installing one is hiding the wires leading to the rear speakers.
If you want to select individual components to make a system, make sure to purchase matching speakers of the same output wattage for the truest sound. You may consider getting wireless rear speakers to simplify installation.
The following companies offer home theaters in a box:n JVC (toll-free 1-800-252-5722, www.jvc.com)
+ Onkyo (toll-free 1-800-229-1687, www.onkyousa.com)
+ Philips (toll-free 1-800-531-0039, www.philips.com)
+ Samsung (toll-free 1-800-726-7864, www.samsung.com)
+ Sony (toll-free 1-800-222-7669, www.sony.com)
+ Yamaha (toll-free 1-800-492-6242, www.yamaha.com)
James Dulley is a mechanical engineer and do-it-yourselfer. Send questions to James Dulley, The Sensible Home, St. Petersburg Times, 6906 Royalgreen Drive, Cincinnati, OH 45244. Visit his Web site at www.dulley.com to download bulletins, tour his energy-efficient home, post questions for other readers and find other information.