Panasonic TH-PX20U review: Panasonic TH-PX20U

Review summary
Panasonic has consistently made some of the best-performing plasma panels over the years, but the TH-42PX20UP isn't quite up to past efforts. Don't get us wrong; this is one slick-looking TV with a nice feature package and excellent connectivity. It also has higher resolution than the excellent PT-42PA20U, and its picture trumps that of many other 42-inchers. However, it lacks an important video-processing circuit common to almost all other high-def displays, and its black-level performance isn't top-notch. So unless you watch a preponderance of HDTV, plan to use it as a computer monitor, or are willing to pay extra for its clear cosmetic advantages, the TH-42PX20UP isn't as good a value as its lower-resolution cousin.
Note: Panasonic also makes an industrial version of this panel with different styling and fewer features, dubbed the TH-42PHD6UY. A newer consumer version is also available, model TH-42PX25UP, which includes a built-in HDTV tuner. Otherwise the two are identical.

Editor's note: We have changed the rating in this review to reflect recent changes in our rating scale. Click here to find out more.

The TH-42PX20UP is perhaps the most attractive Panasonic plasma ever to grace our lab. Its ultrasleek high-tech design is sure to please even the most discerning interior decorator, let alone your average couch potato. A 3-inch bezel surrounds the screen, and its black color--as opposed to silver--lends additional impact to the picture.
A flip-up door below the center of the screen houses the front-panel inputs and some of the panel's key function buttons. The door also conceals a 15-pin VGA input for computer use, an SD memory card slot for digital picture viewing, and a PC Card slot to accept other types of digital camera media.
Despite the high price of this panel, the remote is virtually identical to those found on standard Panasonic TVs. It's sleek and fairly well laid out and has illuminated keys. The internal menu system is also identical to Panasonic's consumer TV line and is reasonably intuitive in its navigation and use. Although billed as an "HDTV plasma display," the TH-42PX20UP's native resolution of 1,024x768 is not technically high enough to earn it that status. (True HDTV starts at 1,280x720.) However, its resolution is significantly higher than that of less expensive EDTV models with 852x480 pixels, such as the PT-42PA20U. Keep in mind that you'll notice increased detail only when watching HDTV or computer sources; standard TV and DVD do not benefit from the TH-42PX20UP's high native resolution.
Unlike 1,024x1,024 panels that use ALIS technology, such as Philips's 42FD9954, each of this Panasonic's pixels is a discrete physical unit, which helps improve black-level performance, among other things. Like most plasmas, the TH-42PX20UP can display just about any signal and scales it to fit its pixels. It can't handle a direct 720p input, however, so 720p HDTV channels such as ABC and ESPN need to be converted to 1080i by the external tuner--which is something you'll need if you want to watch high-def.
The TH-42PX20UP's feature package is quite comprehensive. Two-tuner picture-in-picture heads the list, and the SD memory card slot for digital picture viewing is also uncommon among plasmas. Unique to Panasonic is the panel's PC Card slot, also located on the front panel. There's an NTSC tuner on board to connect to an antenna and some cable systems.
A selection of preset color temperatures and four picture modes (such as Cinema and Standard) offer some user control. Unfortunately, Panasonic forgot to include individual picture memories for each input, a feature found on most other high-end TVs. That means you can't set contrast, brightness, and the rest separately for every source. The four available aspect-ratio modes don't work with HDTV sources.
Although you wouldn't know it by looking, the TH-42PX20UP sports left and right stereo speakers that are artfully concealed in the bezel around the screen. And in case you want to enjoy a semblance of surround sound without all those speakers, a pair of simulated surround modes is on board.
The connectivity of this plasma is quite comprehensive. The rear panel sports two sets of broadband component-video inputs with stereo audio, two A/V inputs with S-Video, two RF antenna inputs, and one set of A/V outputs with composite video only. The TH-42PX20UP is one of the few current plasmas with an HDMI digital input, which connects to next-generation DVD players and HDTV tuners. It's backward-compatible with DVI as long as you get an adapter. The front-panel A/V inputs described above also include a 15-pin VGA-style input for computer hookup. After a thorough calibration for both DVD and HDTV sources (see the geek box for details), we sat back and watched a variety of DVD and HDTV material. Dark scenes are the biggest challenge for plasma, and our new torture test is the Alien DVD, which is mostly dark. The TH-42PX20UP fared better than most other plasmas we've seen, but not quite as well as the lower-resolution TH-42PA20U. The blackness of space was quite dark, but extremely dark areas revealed some false-contouring artifacts and telltale dancing pixels. Bright scenes such as the shuttle launch sequence on the test DVD Digital Video Essentials looked really good using our Denon DVD-2900 running progressive scan.
Frankly, we were shocked to find that the panel lacks the all-important 2:3 pull-down in its video processing, which removes artifacts such as jagged edges and moving lines from film-based material. A progressive-scan DVD player is a must with this plasma, but it won't solve the problem completely. Since lots of shows are still shot on film, folks who watch a lot of standard TV from cable, satellite, or off-air antennas are likely to notice those artifacts. 
In terms of color reproduction, the TH-42PX20UP suffered from red push out of the box, meaning that reds were oversaturated and garish in relation to other colors. We were able to fix this problem in calibration, but if you don't get the set professionally calibrated, you may have to turn down the color in the picture menu to achieve a level that, for example, doesn't give white people a pinkish hue. We also noticed that reds appeared a bit orange.
HDTV material looked mostly good, especially with bright material that was shot in HD as opposed to program material that was transferred from film. For example, the Discovery Channel looked spectacular, but 1492: Conquest of Paradise, a film original transferred to HD airing on HDNet, showed some video noise and moving-line artifacts.