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Philips 42PF9831D review: Philips 42PF9831D

Philips 42PF9831D

David Katzmaier Editorial Director -- Personal Tech
David reviews TVs and leads the Personal Tech team at CNET, covering mobile, software, computing, streaming and home entertainment. We provide helpful, expert reviews, advice and videos on what gadget or service to buy and how to get the most out of it.
Expertise A 20-year CNET veteran, David has been reviewing TVs since the days of CRT, rear-projection and plasma. Prior to CNET he worked at Sound & Vision magazine and eTown.com. He is known to two people on Twitter as the Cormac McCarthy of consumer electronics. Credentials
  • Although still awaiting his Oscar for Best Picture Reviewer, David does hold certifications from the Imaging Science Foundation and the National Institutes of Standards and Technology on display calibration and evaluation.
David Katzmaier
10 min read
We've tested a few of Philips's Ambilight-imbued TVs over the last couple of years, including models such as the 42PF9830A LCD and the 42PF9630A plasma, but we've never been sold. The idea says that a set of lights that illuminate the area behind the TV--and change in color and intensity along with the onscreen image--can help increase your viewing enjoyment. Now we've got nothing against a static backlight, which can be a great way to reduce eyestrain if you're watching a bright TV in a dark room from a medium-to-long seating distance, and Ambilight can certainly be static too--but you can buy a separate backlight yourself and put it behind any TV to get the same (or better) effect.

For people who happen to like Ambilight, however, the Philips 42PF9831D is undoubtedly king of the hill. It's the first model with lights on all four sides of the screen, and it goes one better by extending its fuselage beyond the edge of the frame to provide a white surface off of which the lights reflect, reducing their dependence on the walls behind the TV. We still found active Ambilight distracting, however, and in general, the picture quality of the relatively expensive 42PF9831D ($3,999 list) wasn't up to the standards we expected. Unless you really value the impact and panache of Ambilight, you'll be happier with another HDTV. The first thing we noticed about the Philips 42PF9831D is that it's big. At 50.4 by 34.3 by 4.5 inches (WHD) without the snazzy glass stand (and 50.4 by 36.9 by 11.4 with it), this 42-inch LCD is even larger than most 50-inch plasmas. Nearly all of that extra size can be chalked up to the distinctive white border, or skirt, around the thick, glossy black bezel that in turn surrounds the screen. For ourselves, we generally prefer a flat-panel look that's more picture and less frame, but some people might like the unique styling.


Philips 42PF9831D

The Good

Unique lighting fully surrounds the screen and can help reduce eyestrain; eye-catching design; slick remote; full feature package including CableCard and picture-in-picture.

The Bad

Expensive; active lighting can be distracting; much larger than most 42-inch flat-panels; reproduces relatively light blacks; below-average off-angle viewing; no independent input memories; lacks backlight control; no dedicated PC input.

The Bottom Line

Ringed by glowing colored lights, the Philips 42PF9831D definitely dares to be different, but its high price and not-so-glowing picture quality reduce its appeal.

Philips installed the skirt so the 42PF9831D's 4-way Ambilight backlighting would show up regardless of what kind of background you set the TV up against. One side-effect of the white frame is that the wall behind the TV doesn't pick up quite as much of the light as with standard Ambilight models, which are designed to shine directly on the wall.

The style continues with Philips's sharp-edged remote. This large, glossy black clicker looks like no other, with slightly raised buttons arranged in orderly rows for a slick designer look. The remote doesn't have backlighting, however, and the lack of delineation among keys means you'll have a more difficult time operating the TV by feel.

Philips has improved its menu system, which is now at a level of usability only slightly lower than other HDTVs. Navigation among items is mostly intuitive, utilizing the directional cursor, and individual items are accompanied by text explanations. We would have liked the menu to be partially transparent to the onscreen picture--as it stands, all but the picture-affecting selections obscure the entire screen, and even those take up too much of the screen for our taste. There's also a secondary Option menu that offered quick access to a few seemingly random functions, such as closed captions, PIP format, secondary audio tracks, and the content of any attached media cards or USB thumbdrives. The Philips 42PF9831D's biggest differentiating feature is the latest iteration of the company's Ambilight technology, which it dubs "Ambilight full surround." Ambilight consists of colored fluorescent lights along the edges of the screen that illuminate, in this case, the white skirt around the TV, and secondarily, the walls and other objects around it. As a "full-surround" model, the 42PF9831D has lights on all four sides of the screen, and each of the banks of light can react independently to onscreen material.

There are five different Ambilight modes: four that react to the onscreen picture and one, called Color, that does not. The four dynamic modes offer varying intensities and rates of transition, from the relatively mellow Relaxed mode to the frenetic Action mode. Controls that affect the dynamic modes include lamp brightness as well as two that sound as if they were borrowed from a stereo system: balance, which is said to adjust the color and intensity on the sides, and separation, which affects how differently each of the four sides reacts to the four quadrants of the picture. The fifth mode simply creates a constant color around the screen. It offers four presets, with Cool White coming the closest to the ideal 6,500K backlight color (although it was still rather blue), as well built-in controls to create a custom color. No matter what adjustments we tried, we couldn't get closer to the standard than Cool White.

Aside from Ambilight, the Philips 42PF9831D brings a comprehensive set of features to the table. The panel has a native resolution of 1,366x768 pixels, standard among LCD TVs, which should resolve every detail of 720p HDTV. All sources, including HDTV, DVD, standard TV, and computer, are scaled to fit the native pixels.

Philips touts its ClearLCD technology, which is said to improve many aspects of picture quality (see Performance for more). The 42PF9831D also has both an ATSC tuner and a CableCard slot, enabling it to tune HDTV and digital channels over-the-air or via cable without the box. Unlike some CableCard-equipped sets, it does lack a third-party EPG, however, so you won't be able to use a program grid to tune CableCard channels.

There is a fine selection of six aspect ratio modes for standard-def sources, but you get only one with high-def. Other conveniences include picture-in-picture, a favorite channels list, and multimedia capability. A multicard slot and/or a pair of USB ports on the side panel can interface with cards and/or thumbdrives to display digital photos and play music files on the TV.

People who like to adjust the picture will probably be disappointed that the Philips 42PF9831D lacks any kind of independent input memories. Instead, it offers just one Personal preset that applies to each input, making it impossible to adjust different sources separately. None of the five picture presets can be adjusted--doing so just reverts to Personal, erasing all of your settings in the process. We also missed a backlight control, which, in other LCDs, can be adjusted to achieve better black levels.

The range of additional picture controls includes three adjustable color-temperature presets, among which Warm comes closest to the standard; a digital-processing menu offering Pixel Plus and Standard choices--we preferred Standard, since Pixel Plus introduced some edge enhancement; four steps of dynamic contrast, where Off was the best choice, since the others modified light output on the fly; four levels of noise reduction; a color-enhancement control that's best left off to maintain the best color temperature; and four steps of active control, which we left set to Off for critical viewing, again because it modified the picture on the fly.

Philips included a standard but by no means exemplary array of connections on the 42PF9831D. There's a pair of HDMI inputs; one A/V input with a choice of RGB, component video, S-Video, or composite video; one with a choice of S-Video or composite video; one with only component video; a digital audio input; an RF-style antenna input; a digital audio output, and an analog audio out. To connect a PC, you'll need to monopolize one of the HDMI inputs (connecting via a DVI-to-HDMI adapter) or use the first A/V input's RGB capability, which eliminates one of the component-video connections. Overall, we were relatively disappointed by the picture quality of the Philips 42PF9831D. Flat-panel LCD technology has come a long way in the last couple of years, but this set didn't produce as impressive a picture as the current competition's, especially given the price. Its relatively light blacks, less-than-stellar off-angle viewing, and relatively inaccurate color decoding were the major culprits.

When we set up the Philips 42PF9831D for critical viewing in a darkened room, we also put it next to a few other LCD TVs, namely the 40-inch Sony KDL-40XBR2, the 42-inch Vizio L42 HDTV and the 37-inch HP SLC3760N. During the course of adjusting the 42PF9831D, we missed the ability to turn down the backlight behind the screen, which might have improved the set's black-level performance. We did access the service menu to perform a grayscale calibration, which improved the Philips's color accuracy somewhat over the Warm color temperature preset. For our full user-menu settings, check out the Tips & Help tab above.

We noticed during setup that the Philips 42PH9831D delivered a significantly sharper image when fed a 720p HDTV source rather than a 1080i source, so we recommend going 720p whenever possible with this set. That's why we chose to evaluate the set using the 720p HDMI output from our Denon DVD-3910 upconverting DVD player rather than the 1080i output from our standard Toshiba HD-A1 HD-DVD player. We chose the great-looking The Interpreter DVD, and during the first relatively dark scene, where Silvia Broome (Nicole Kidman) asks a fellow U.N. employee to stash her bag in his cubicle, the Philips had a difficult time competing against the other sets. All of the others, including the inexpensive Vizio, conjured a deeper color of black in dark areas such as the letterbox bars, Silvia's black jacket, and her coworker's curly black hair. Details in the shadows, such as the curls themselves and the jacket's lapels, were also less distinct on the Philips.

Philips's ClearLCD technology utilizes different fluorescent backlights behind the screen (Hot Cathode vs. traditional Cold Cathode), which the company says can cycle on and off more quickly than traditional backlights. As a result, the company claims improved black levels, viewing angle, and motion reproduction. We didn't see any evidence of improvement in the first two categories in our tests, but we did notice slightly less blur in some areas during motion. The improvement was most obvious in text crawls, such as the words below an ESPN baseball game, where the edges appeared just a bit sharper on the Philips than on the other LCDs, especially the Vizio. We watched a variety of other program material, including fast and slow pans, quick camera movement, and fast-object motion, such as baseballs from the center-field camera, tennis balls during the U.S. Open, and soccer balls on HDNet, and really couldn't discern the same slight improvement as we saw on the text crawl. ClearLCD helps if you're especially susceptible to blurring in LCDs, but in reality, most new LCDs handle motion well enough for just about anybody.

Another issue that plagues some LCDs during dark scenes is screen uniformity, and again, the Philips fell short. The upper-right and -left corners of its screen were visibly lighter than the other areas, and there were also some lighter streaks across the middle of the screen. Also, when we sat off-angle, the screen became noticeably brighter as well as discolored (tending a bit toward magenta)--more so in both cases than that of any of the other LCDs we had onhand.

The relatively light blacks also contributed to the Philips's less-intense colors. Despite increasing the color control to 75, we still felt that the 42PF9831D looked relatively washed out compared to the others. As Broome and Tobin Keller (Sean Penn) take in the diner, for example, her pale face looked a bit too pale, and the deep, red leather of the booth was less saturated than it should have been. The Philips's inaccurate color decoding, which made red and green less-intense, didn't help.

With standard-def sources, the 42PF9831D turned in an average performance. In its favor, the TV detected and implemented 2:3 pull-down properly and quickly in both Pixel Plus and Standard modes. The set's noise reduction also cleaned up some of the snowy motes of noise in shots of skies from the HQV disc, although it wasn't nearly as effective in this regard as the Sony. On the flipside, the Philips had a hard time smoothing out difficult moving diagonal edges, whether in Pixel Plus mode or not, and fine details appeared a bit softer than we'd like to see.


In person, Ambilight certainly looks distinctive. The white skirt around the edge of the Philips really sets off the glossy black frame around the picture, and the fade of the light from bright to dimmer toward the edge helps maintain a kind of otherworldly appearance. The skirt makes the light seem much more dramatic than we're used to seeing when Ambilight reflects only off of the back wall, and the added effect of the top and bottom lights makes a big difference, too. Overall, this is the most dramatic Ambilight presentation we've seen yet.

That doesn't mean we love it though. The four dynamic Ambilight modes, which change according to the picture content, still seemed as distracting as ever to our eyes. The Relaxed setting was the least objectionable, but we still found ourselves wishing the light would just sort of settle down--we were constantly finding our attention diverted by the change in lights. During the credit sequence of The Interpreter, for example, we were surprised when the Ambilight suddenly became yellow for no discernable reason as it followed the security chief through a U.N. hallway. A helicopter shot over New York again caused a sudden change, this time making the lights incongruously brighter. The disconnect between onscreen content and the lights was most noticeable when the image faded to black but the lights remained relatively bright. We watched for a couple of hours continuously, but afterward found ourselves wishing for a constant, nonchanging backlight--or none at all.

Of course you can set the Philips 42PF9831D's Ambilight to a constant glow, and we found the Cool White mode most pleasing for that effect. Indeed, this mode was welcome in our dark room when we sat relatively far back from the screen, since the light did help reduce eyestrain. We still wish it was capable of becoming a bit dimmer, however.

Before color temp (20/80) 7,328/6,179K Average
After color temp 6,631/6,588K Average
Before grayscale variation +/- 197K Good
After grayscale variation +/- 149K Average
Color of red (x/y) 0.633/0.338 Good
Color of green 0.275/0.602 Good
Color of blue 0.145/0.071 Average
Overscan 3.8 percent Average
Black-level retention All patterns stable Good
2:3 pull-down, 24fps Yes Good
Defeatable edge enhancement Yes Good


Philips 42PF9831D

Score Breakdown

Design 7Features 8Performance 4