How it Works
HDTV is all about information. The more information packed into the picture appearing on your television set, the sharper the image will be. With HDTV, there are two key ingredients. First, a special HD television set or monitor that’s capable of displaying more picture information than ordinary TV sets. And second, a source of specially produced HD programs to “feed” the higher-resolution signals to your new TV. (Cable companies today are the most popular source in the U.S. for providing HD signals.)
Terms and technologies
Fortunately, you have to learn just a few important terms in order to really understand what HDTV is all about. (Or what the sales guy at the local electronics store is talking about.)
Aspect Ratio describes the width of the TV screen in proportion to its height. When people talk about wide-screen TVs, they’re referring to the 16:9 aspect ratio. Most HDTV programs are delivered in this widescreen format. A 16:9 aspect ratio fills more of your natural field of vision and creates a more cinematic experience. In comparison, standard TVs have an aspect ratio of 4:3, slightly wider than a square. In many instances images are cropped to accommodate your 4:3 screen, resulting in a loss of picture.
Pixels are the picture elements that make up the images onscreen. More pixels mean more detail. The highest pixel count is available with high definition television (HDTV), where up to 2 million pixels can be displayed.
Resolution is displayed on screen by horizontal and vertical pixels that make up the on-screen image. The number of pixels determines the resolution, and the best resolution on a digital television is available with an HDTV set. For example, lines of resolution you see on older, analog television sets are 705 (width) x 485 (height), at best. In comparison, HDTV offers screen resolutions of 1280 (width) x 720 (height) or 1920 (width) x 1080 (height).
Dolby 5.1 is the specification for the surround-sound system that accompanies HDTV. It’s the same system used in many movie theaters. Older, analog television sets offer only two channels of audio, left and right. Dolby Digital 5.1 sends a digital audio signal to 6 speakers that can be arranged throughout the room, enveloping you with rich sound from every angle.
Ready to buy?
Your best bet is to head down to your local electronics store after doing some additional online research. Your dealer can help you determine which of three main types of HD monitors is best for you and your home.
But buying an HDTV set is just one part of the equation. You’ll also want to call your cable company to start receiving special HD channels. (Otherwise it’s sort of like building a swimming pool in the backyard but forgetting to fill it up with water.) One advantage of Digital Cable is that there’s no hassle of added antennas or bulky rooftop equipment. All you need to do is swap out your existing box for one that can receive HDTV and begin to experience the next generation of television. Cable companies typically offer the HD version of popular TV channels on a specially designated channel number. (For example, if CBS is on channel 2 in standard definition, the high-def version may be on channel 702 on your Digital Cable service).