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Sony KLV-40ZX1M - 40 LCD TV review: Sony KLV-40ZX1M - 40 LCD TV

Sony KLV-40ZX1M - 40 LCD TV

David Katzmaier
David Katzmaier Editorial Director -- TVs and streaming
David runs CNET's home entertainment division, where he leads a team that covers TVs, streaming services, streaming devices and home audio. If he doesn't know something about the gear you use to keep yourself entertained at home, it's not worth knowing.
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.
11 min read


Sony KLV-40ZX1M - 40 LCD TV

The Good

Ultrathin panel creates a high-tech design; hidden cords; relatively accurate color; numerous picture controls; energy efficient.

The Bad

Extremely expensive; subpar black-level performance and color saturation; uneven screen uniformity; scant connectivity with just one HDMI input.

The Bottom Line

As the first large-screen edge-lit LED-based LCD, Sony's KLV-40ZX1M looks stunning turned off, but it falls short when powered up.

Editors' note (March 4, 2010): The rating on this product has been lowered because of changes in the competitive marketplace, including the release of 2010 models. The review has not otherwise been modified. .

Among all of the technologies that enable LCD to attempt to rival the picture quality of the best plasmas, LED backlighting is the most effective we've seen. LED-equipped models we've reviewed in the last couple of years have demonstrated superb black-level performance, mostly thanks to their local dimming circuits, which let the TVs dim or turn off the backlight in specific areas of the screen when it's not needed. But now a new twist has arrived in the form of "edge-lit" LED backlights, and the first such model we received to review is Sony's KLV-40ZX1M.

Edge-lit LED-powered displays such as this Sony and upcoming Samsung models announced at CES do not employ local dimming, so, as you might expect, their black-level performance can't match that of displays that do. On the other hand, edge-lit LED backlights allow the panels to be thinner than ever--the KLV-40ZX1M's panel, for example, measures just 1.1 inches thick. As a result, this TV looks stunningly thin and high tech, especially when seen from the side, and its LED technology allows for improved energy-efficiency. Naturally, you'll pay a good deal more for the privilege of owning a first-generation technology, although we expect edge-lit LED LCDs arriving later this year to cost less.

The gorgeous KLV-40ZX1M panel is a study in minimalist design. Black-textured metal surrounds the screen to an equal width on all four sides, regrettably interrupted by a line of indicator lights and white lettering on the lower right.

Sony KLV-40ZX1M
Here's what you're paying for: a 40-inch diagonal screen that's barely over an inch thick.

Unfortunately, the included stand spoils some of the panel's sleekness with its circular shape and relatively chunky base. A small arm supports the panel above the stand, which does not offer any swivel capability. It took us a minute to figure out that Sony had stashed the speakers inside the base of the stand--meaning that if you wall-mount the TV, you'll have to forgo speakers or attach the company's optional speaker bar (model SS-WAL700, $399). A specialized wall bracket, model SU-WL700, can be purchased for $299.

Sony KLV-40ZX1M
The included, chunky circular stand might not swivel, but it does hide a set of speakers.

In addition to containing hidden speakers, the stand incorporates another slick design element. The stand's arm serves as a channel to hide the AC and HDMI cables running from the back of the panel. When you connect the included, flush-mount-friendly cables and use the snap-on plate to hide the connections, the cables sprout unobtrusively from the base of the stand at the rear, as opposed to dangling from the back of the panel. For folks interested in hiding evidence of connections, the KLV-40ZX1M does the job better than any display we've seen.

Sony KLV-40ZX1M
Clever panels hide the HDMI and power cables, which exit from the back of the stand's base.

Including stand, the KLV-40ZX1M measures 38.9 inches wide by 26.9 inches tall by 12.1 inches thick and weighs 33.1 pounds. Without the stand, the panel's dimensions become 38.9 inches wide by 23.6 inches tall by 1.1 inches thick and its weight is a feathery 26.9 pounds. Despite its thinness, the panel felt sturdy enough, although we couldn't shake the vague feeling of fragility imparted by such a thin panel.

Sony's remote control is a poor effort in design, with way too many like-size and like-shaped buttons that make finding and engaging any one function a real headache. Numerous extra keys, apparently for use with devices other than the KLV-40ZX1M, are also included, such as four labeled "system control" and a PIP button that implies the display supports picture-in-picture (it does not). The lack of a dedicated key to switch aspect ratio modes is unforgivable. The clicker can command a whopping seven other pieces of gear, but that's about the only compliment we can give it.

We do appreciate that Sony's menu system is relatively simple and straightforward, lacking the fancy XMB interface found on most of the company's standard televisions. Text explanations accompany selected menu items, and everything was easy to find without too much digging.

The edge-lit LED tops the KLV-40ZX1M's feature list, allowing that vanishingly thin profile. As the name implies, the light originates from LEDs arranged along the edges of the panel, as opposed to the standard arrangement where the LEDs are placed evenly throughout the entire panel. Light travels from the edges the middle of the screen via special light distribution grids. See for notes on how it influences picture quality.

In addition to allowing extra thinness, edge-lit LED improves energy efficiency. We tested the power consumption of the KLV-40ZX1M and found that it was quite efficient compared with the only other 40-inch LCD we reviewed last year, Toshiba's 40RF350U. The Sony's post-calibration number (with light output equalized) was an impressive 79.4 watts, compared with 115.9 watts for the Toshiba. We expect larger-screen edge-lit LED displays on sale later this year to provide a better comparison to more recent displays. It's also notable that although the KLV-40ZX1M is Energy Star 3.0-compliant, its default picture setting is the very bright (and relatively power-hungry) Vivid mode, and there's no initial home/store menu to encourage viewers to engage a darker, less-wasteful mode like Standard. For full details on the KD-40ZX1M's energy use, check out the .

Sony KLV-40ZX1M
The Motion Enhancer controls the Sony's dejudder processing.

The Sony KLV-40ZX1M offers a 120Hz refresh rate along with Sony's MotionFlow dejudder processing. The set also includes four adjustable picture modes, although one, labeled Vivid, lacks a number of advanced adjustments. Such adjustments available on the other modes let you fine-tune color temperature, tweak color gamut, and choose from four gamma presets, among other settings. Sony's CineMotion processing affects 2:3 pull-down; there's a Game mode to remove any potential delay between a game controller and the onscreen action; and there's a Photo/Video optimizer to, well, optimize the picture for display of either still photos or moving video (however, we didn't test it).

Sony KLV-40ZX1M
Full white balance controls, which allow fine-tuning of color temperature, are always welcome.

Aspect ratio control on the Sony is adequate, with three choices for high-definition sources and a "Full Pixel" option that displays 1080i and 1080p sources without scaling. Unfortunately, there's no dedicated button on the remote to switch between different aspect ratio modes; you'll have to delve into the menu to do so.

Also notable are the features the KLV-40ZX1M lacks. First off there's no built-in tuner, making this display a "monitor" as opposed to a true TV. As you can imagine, it also lacks tuner-related features, such as favorite channels lists. Of course, lack of a tuner is a moot point if you connect a cable or satellite box.

Sony KLV-40ZX1M
That's right, this monitor has just one HDMI input.

More problematic is the set's limited connectivity. All told, the KLV-40ZX1M has just one HDMI input and no other connections. That's fine if you only want to connect a high-definition cable or satellite box, or maybe a PC with a digital output and nothing else, but if you'd like to expand your source options you'll need to buy an additional HDMI switcher or an AV receiver with HDMI switching and analog upconversion (if you want to connect devices that lack HDMI outputs). Sure we'd like to see more than one HDMI input, or maybe an analog video input of any sort, but naturally any extra inputs would probably spoil the slick, hidden-cord design.

We couldn't help but be disappointed by the Sony KLV-40ZX1M's overall picture quality, especially given the excellent performance we've seen on LED-based LCDs with local dimming. Black levels were quite light, and we noticed more uniformity issues, notably brighter edges relative to the middle of the screen and poor off-angle viewing, than we're willing to forgive for a display at this price.

The Cinema preset came closest to what we'd consider ideal dark-room picture settings, with solid precalibration color temperature in the Warm 2 setting, although Cinema was still relatively dim at just 30 footlamberts. Our standard calibration improved the color a bit, although we couldn't rid the set of its bluish tinge in dark areas. For our full picture settings, check out the bottom of this blog post.

For our comparison we didn't have any other edge-lit LCDs on hand, but we did incorporate a few highly-rated models to compete against this expensive Sony, including the company's own "local dimming" LED-powered KDL-55XBR8, the less-expensive Samsung LN52A650 from the standard LCD camp and the like-priced Pioneer PRO-111FD from plasma land. Our main batch of image quality tests was performed partly with the new release of "Ronin," one of our all-time favorites on Blu-ray played by the PlaySation 3.

Black level: Sonys edge-lit LED could not produce as deep a shade of black as any of the other displays in our comparison. In the dark dockside shots from Chapter 6, for example, the letterbox bars, night sky, shadows, and black asphalt all appeared slightly lighter than the lightest of the bunch, the Samsung A650, and not nearly as inky as either of the other two. Details in shadows, such as the dark jackets of Sam and Vincent, also seemed a bit more-obscured on the Sony KLV-40ZX1M, although the difference wasn't as stark.

We also noticed that when scenes faded to black, the set's screen would dim noticeably. In normal program material, while watching "Ronin" go from light to dark scenes and back, the fluctuation wasn't hugely distracting, but we wish it wasn't obvious at all. We saw it again, and in a more distracting way, in the transition from Chapter 3 to 4 in "I Am Legend," where Will Smith locks up his house for the night. The entire screen dimmed and then turned up again as the screen faded to black and back.

Color accuracy: Overall, colors looked relatively accurate on the Sony, thanks to its solid primary and secondary colors and linear grayscale in most brightness conditions. In Chapter 11, for example, as Sam and Deirdre stroll through the park on the way to the hotel, the green of the grass and trees, along with the red of the carousel in the background and blur of the water on his map all compared well with our reference Pioneer. On the other hand, Deirdre's skin appeared a bit duller and less lustrous than we saw on the other displays, and despite increasing the color control significantly, saturation in general was quite a bit less punchy and lively. We chalk it up to the KLV-40ZX1M's weak black-level performance, which also negatively influences apparent saturation.

As we mentioned, very dark areas, like the shadows in the scenes in Chapter 6 and the letterbox bars, for example, took on a blue tinge, an issue common to many LCDs that we couldn't fix with any amount of adjustment without spoiling lighter areas' accuracy.

Video processing: We're not fans of dejudder processing, but to our eyes, Sony's MotionFlow in the Standard position has usually done the best job of any such mode at providing that extra smoothness without looking too unnatural or making film look too much like video. Standard on the KLV-40ZX1M, however, appeared less natural than Standard on the XBR8 (or Low on the A650), smoothing out the jerky motion of the first epic car chase (Chapter 14)--in particular the realistically unsteady camera that follows Sam as he launches an RPG from the open sunroof--entirely too much.

Of course, engaging High in the same scene made things look even less realistic and imparted an almost cartoonish smoothness to the breakneck pacing. It also introduced the usual dejudder artifacts, like breakup in the mountain walls and the overhead shot of the brown Mercedes after Sam's successful shot. We wonder what director John Frankenheimer, who takes his car chases seriously, would have to say about the effect of dejudder on these scenes.

In terms of resolution, the KLV-40ZX1M performed as expected. It delivered every line of still 1080i and 1080p test patterns, properly deinterlaced both film- and video-based 1080i sources, and resolved between 300 to 400 lines of motion resolution with dejudder turned off and 600 to 700 when it was turned on. The set's motion resolution results are typical of standard 120Hz LCDs.

When we set our PS3 to output 1080p/24 video and turned off the KLV-40ZX1M's dejudder processing, the Sony performed as well as expected, preserving the cadence of film nicely. Our favorite pan over the deck of the "Intrepid" from "Legend" provided the best example, where the motion was every bit as smooth--but not too smooth--as on the other 120Hz LCDs and the 72Hz Pioneer.

Uniformity: We expected a display lit from the edge to be at a uniformity disadvantage compared with one lit evenly from behind, and indeed the KLV-40ZX1M showed below-average uniformity. The problems were most visible in the letterbox bars above and below the image, which showed brighter areas in all four corners and the sides, while the middle of the bars looked darker. In very dark scenes, we noticed that the left side of the screen was brighter than the right. That said, in bright scenes the Sony didn't exhibit any overt uniformity problems.

Like other LED based displays we've reviewed, the edge-lit KLV-40ZX1M also performed quite poorly when seen from off-angle. In dark scenes when we moved a seat or two away from center on the couch, that brightness from the edges would creep even further into dark areas and wash out contrast and colors worse than we saw on the other displays.

Bright lighting: As usual for a matte-screened LCD, the KLV-40ZX1M did a solid job of reducing glare from ambient light in the room, outclassing the Samsung and the Pioneer plasma in this regard, and performing about as well as the Sony XBR8.

Standard-definition: Since the Sony KLV-40ZX1M does not have any standard-definition inputs, we didn't test its SD performance.

PC: With PC sources delivered via HDMI, the monitor automatically went into PC mode, which disables many of the picture adjustments. PC performance was excellent, as expected, with the panel resolving every detail of a 1,920x1,080-pixel source and delivering crisp, clear text with only a slight hint of edge enhancement.

Before color temp (20/80) 6496/6554 Good
After color temp 6479/6525 Good
Before grayscale variation 241 Good
After grayscale variation 183 Average
Color of red (x/y) 0.652/0.333 Average
Color of green 0.303/0.599 Good
Color of blue 0.158/0.066 Average
Overscan 0.0% Good
Defeatable edge enhancement Y Good
480i 2:3 pull-down, 24 fps N/A  
1080i video resolution Pass Good
1080i film resolution Pass Good

Sony KLV-40ZX1M Picture settings
Default Calibrated Power Save
Picture on (watts) 160.65 79.46 46.88
Picture on (watts/sq. inch) 0.23 0.12 0.07
Standby (watts) 0 0 0
Cost per year $49.72 $24.59 $14.51
Score (considering size) Good
Score (overall) Good
*Cost per year based on 2007 average U.S. residential electricity cost of 10.6 cents per kw/hr at 8 hours on/16 hours off per day.

How we test TVs.


Sony KLV-40ZX1M - 40 LCD TV

Score Breakdown

Design 9Features 5Performance 4
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