The least expensive--and most common--type of jumbo TV is a rear-projection set. Some projection sets have three cathode-ray picture tubes (CRTs), smaller versions of the tubes used in conventional sets. The images from those small tubes are projected onto the back of a 42- to 70-plus-inch screen, hence the name rear-projection TV. Microdisplay sets use liquid-crystal display (LCD), digital light processing (DLP), or liquid crystal on silicon (LCoS) technology in place of CRTs. These TVs are slimmer, lighter, and more expensive than comparable CRT-based sets. More of them are appearing in stores, and their prices are starting to drop.

WHAT'S AVAILABLE

Major brands include Hitachi, Mitsubishi, Panasonic, Philips, RCA, Samsung, Sony, and Toshiba.

The smallest sets, measuring about 42 inches diagonally, offer only a few more inches of screen than a conventional 36-inch set. Rear-projection sets with 50- to 60-inch screens are the best sellers. The largest of these TVs have screens measuring 70 inches or more. Keep in mind that a set with a 57-inch screen could be overwhelming in a modest-sized room. CRT-based sets are floor-standing units about 24 to 30 inches deep that take up about 8 square feet of floor space. They weigh about 200 pounds and are mounted on wheels. Microdisplay models may require a stand. Most are about 15 to 20 inches deep and weigh about 100 pounds.

Most rear-projection sets now on the market are digital (HD-capable) sets, but there may still be a few analog models. Both types can accept regular TV signals, but HD-capable sets can best display the superior images you get from DVD players and from HD sources (antenna, satellite, digital cable, or digital-video players/recorders). HD-capable sets generally cost a few hundred dollars more than comparably sized analog models. Most have a wide-screen 16:9 aspect ratio that resembles a movie-theater screen.

Within the HD category, there are three types of TV sets.

HD-ready sets. Also called HDTV monitors, these sets can display standard-definition analog programs (which still account for most non-prime-time TV broadcasts) on their own. To display digital programs, they require a digital tuner to decode those broadcasts. If you're getting your HD programming from cable or satellite, your digital cable box or satellite receiver has the appropriate digital decoder built in. All you have to do is connect your HD-ready TV to the box and you're all set. Cable companies charge a small rental fee for digital or HD-capable boxes. To receive HD via satellite, you need an HD receiver and special dish antenna(e). Together, these cost about $300, but you may be able to get them from the satellite company at little or no charge as part of a promotion.

You can also get digital broadcasts, including HD, over the air, via an antenna. To do so, you'll have to buy a digital tuner called an ATSC (Advanced Television Systems Committee) tuner--the external box costs a few hundred dollars. However, there's no charge for service as there is with cable or satellite. Some satellite receivers also offer a built-in ATSC digital tuner. To receive digital programming via antenna, you must be fairly close to a transmitter, with an unobstructed view. With digital signals, you'll either have a clear, strong signal or none at all.

Integrated HDTV sets. Also called HDTVs, these have the ATSC digital tuner built in, which enables them to decode any digital signals, including HD, with no additional equipment when used with a roof antenna. You may be able to receive the major networks' HD offerings transmitted over the air in your area, but not the premium channels available on satellite and cable. To get HD via cable or satellite, integrated sets require an HD-capable cable box, CableCard, or satellite receiver--the built-in digital tuner only works for off-air digital broadcasts.

Starting in July of 2005, all new TVs with 36-inch or larger screens --a category covering virtually all projection TVs--were required to have a built-in digital tuner to comply with a government ruling.

Digital-Cable-Ready (DCR) sets. Some new integrated models, called digital-cable-ready (DCR) or plug-and-play sets, can receive digital-cable programming without using a set-top box. For HD and premium cable programming--and possibly for any digital programming--you must insert a CableCard into a slot on the set. You usually have to pay a few dollars a month to rent the card from the cable company. Current DCR TVs are not interactive, so even with a CableCard in the slot they can't provide features such as an interactive program guide, video on demand, or pay-per-view ordering via remote. Second-generation DCR TVs and CableCards should be here soon, and they're expected to have two-way capability, allowing for interactive features. Integrated sets typically cost more than HD-ready sets, with digital-cable-ready models costing the most.

IMPORTANT FEATURES

Virtually all projection TVs have the features that are now standard on regular 27-inch and larger TVs, plus some features that aren't so common--such as dual-tuner picture-in-picture (PIP) or a variant side-by-side picture mode.

Most TVs have several types of inputs that handle varying levels of quality. An antenna/cable, VHF/UHF or radio frequency (RF), input is the most basic connection, and it can be used with almost any video source. A composite-video input will give you slightly better picture quality and is often used with a VCR or regular cable box. An S-video input lets you take advantage of the still-better picture quality from a digital-cable box, a satellite-dish system, a DVD player, or a digital camcorder. A component-video input offers superior quality, making this a good choice for progressive-scan DVD players, high-definition satellite receivers, and HD digital-cable boxes that have the corresponding output. Most HDTVs have DVI or HDMI inputs, which provide a high-quality digital connection to devices such as DVD players, digital-cable boxes, and satellite receivers. DVI signals carry only video; HDMI signals carry audio and video on one cable. The digital-to-digital connection may ensure optimal picture quality. These connections allow the content providers to control your ability to record certain programming. Many sets have more than one of a given type of input. Having two or three S-video or component-video inputs is a plus. For a camcorder or video game, front-panel A/V inputs are helpful.

Audio outputs let you direct a TV's audio signal to a receiver or to self-powered speakers. Integrated digital TVs also include a Dolby Digital audio output for surround sound (available from some digital broadcasts). An automatic volume leveler compensates for the jarring volume jumps that often accompany commercials or changes in channel.

Auto convergence provides a one-touch adjustment to automatically align the three CRTs' images to form an accurate picture. It's much more convenient than manual convergence, which can require time-consuming adjustments. Manual convergence does allow finer control, though. The best bet is a set that has both manual and automatic convergence. (Convergence is not necessary on LCD, DLP, or LCoS models.)

Stretch and zoom modes on wide-screen sets will expand or compress an image to better fill the screen shape. This helps to reduce the dark bands that can appear above, below, or on the sides of the image if you watch content that's not formatted for 16:9 screens. (The picture may be distorted or cut off a bit in the process of stretching and zooming.) Those bars make the picture slightly smaller. On CRT sets (but not LCD, LCoS, or DLP models), the bars can leave "burn in" ghosted images on the screen over time, as can any images left on the screen for long periods--say from a stock ticker.

If you watch many movies, look for a film mode feature on HD sets. This feature is also called 3:2 pulldown compensation or brand-specific names such as CineMotion. This can make moving images that were converted from film to video look less jerky, with less jaggedness around the edges.

HOW TO CHOOSE

Here are some points to consider in choosing a rear-projection TV:

Consider space before settling on screen size. Most rear-projection TVs have screens measuring 42 to 65 inches. You might be tempted by the biggest screens, which can span as much as 70 inches or more, but take a breath--and some measurements--first. Figure out how much floor space you can spare, and plan to view the TV from about 7 to 9 feet away for optimal picture quality.

Weigh depth and price in choosing a display type. Once you know how much room you have, decide whether size or price is more important. CRT-based sets are floor-standing models with deep cabinets mounted on casters. Some take up as much space as an armchair or loveseat. Most microdisplays are tabletop units. You buy a stand separately for a few hundred dollars or more. Would you prefer to save money with a bulkier CRT set or spend more for a slimmer microdisplay?

Consider reliability. CRT technology has been used in rear-projection TVs for years and has generally been quite reliable. Note, though, that any pattern left on a CRT screen for long periods--such as a stock ticker or video game--can burn into the tubes of a CRT-based model, producing a permanent ghosted image on the screen. Most warranties don't cover burn-in. This problem doesn't affect other types of rear-projection TVs. Microdisplay technologies are newer and haven't established a track record for long-term reliability, but they're not vulnerable to screen burn-in. They may require lamp replacement, however, which can cost a few hundred dollars. Factor these considerations into your decision.

Focus on picture quality. It's a little harder to find top picture quality in rear-projection TVs than in plasma TVs, so you'll have to be choosy. The best sets can deliver very good picture quality with HD content and good picture quality for DVDs and regular TV programming. Microdisplays are likely to provide better picture quality than CRT-based models. Within the microdisplay category, we haven't found that any one projection technology was consistently better than another.

Check the viewing angle. Some new models display a better image from off-center than older sets did--a must if a TV will be watched by several people at once. Some sets have wider viewing angles than others. Before buying one, see how the picture looks if you step off to the side or move up and down. With some, you'll see a dimmer, somewhat washed-out image as your viewing position angles away, particularly in a vertical direction.

Expect fine sound quality. Many people connect big-screen TVs to an audio system to provide surround sound, so the quality of the TV's speakers may not be an issue. It may reassure you to know that virtually all the sets we've tested recently produced excellent sound. That's largely because projection sets have bigger speakers than direct-view TVs and bigger cabinets with superior acoustical properties.

Consider installation. Because rear-projection sets are floor-standing units, installation is easier than with front-projection systems or wall-mounted plasma TVs. Still, rear-projection sets are larger and may be somewhat harder to set up than regular TVs, so consider having a professional install your TV.

Weigh the merits of an extended warranty. While extended warranties aren't worthwhile for most products, they may be for high-priced devices using new technologies. Because microdisplay TVs are costly items that haven't yet established a track record for reliability, check into the cost of a service plan. Find out whether in-home service is covered and whether a replacement is provided if a set can't be repaired.

Copyright © 2002-2006 Consumers Union of U.S., Inc.

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