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Sony KDL-EX640 review: Sony KDL-EX640

Sony's EX640 series is one of the better deals from the company, with decent picture quality and features for the price.

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Ty Pendlebury
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Ty Pendlebury

Editor

Ty Pendlebury is a journalism graduate of RMIT Melbourne, and has worked at CNET since 2006. He lives in New York City where he writes about streaming and home audio.

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4 min read

When it comes to buying a TV, no matter how attractive the shiny flagship models may be, it usually makes the most sense to buy the midrange products. While you'd naturally assume that the more advanced models have better picture quality this isn't always the case. Sometimes you're just paying for more features and a worse picture.

sony-internet-tv-kdl-46ex640-46-bravia-ex640-series-led-tv-1080p-fullhd-edge-lit-local-dimming-black.jpg
6.7

Sony KDL-EX640

The Good

The relatively affordable <b>Sony EX640</b> offers deep-enough black levels for the money and commendable color saturation. The design is attractive and the menu system is easy to use.

The Bad

We detected a couple of uniformity issues, black areas can look blue under lights, and shadow detail isn't up there with the better TVs. The wireless dongle takes up a USB port. The SEN portion of the Smart TV interface is so slow that it's kind of a waste.

The Bottom Line

Sony's EX640 series is one of the better deals from the company, with decent picture quality and features for the price.

If you're considering a Sony LED TV and the excellent KDL-HX850 is too rich for your blood, your choice comes down to the KDL-HX750 or the KDL-EX640 I'm reviewing here. After comparing the two directly I'd say it's a pretty easy decision. The EX640 wins because its picture is actually better than that of the more expensive HX750. Despite its spot as Sony's least expensive LED TV, the EX640 offers a very tidy picture for the money, with better blacks than the HX750 and the Samsung UNES6500, and well-saturated colors. Design is a high point, unusual for a midrange model, with a nicely textured finish. The only significant feature it misses is 3D, which should actually please some people.

While the Vizio M3D0KD is better in nearly every way, if you're looking for a TV by one of the "big four" TV makers, the Sony EX640 is a good buy.

Sony EX640 LED TV series is a good value (pictures)

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Series information: I performed a hands-on evaluation of the KDL-46EX640, but this review also applies to the other screen sizes in the series. All sizes have identical specs and according to the manufacturer should provide very similar picture quality.

"="" bgcolor="#CCCCCC">Models in series (details)
Sony KDL-40EX640 40 inches
Sony KDL-46EX640 (reviewed) 46 inches
Sony KDL-55EX640 55 inches

Design
Sony hasn't done anything drastic in the design department in 2012, and as a result, the EX640 series is none too different from last year's EX series. That is, until you get closer: the bezel is metallic and features a stippled finish not unlike a men's electric razor, and it actually looks quite classy. The stand is the standard black rectangle and features a swiveling base.

The bezel features a subtle yet distinctive stippled effect. Sarah Tew/CNET

The remote control is a close-to-bog-standard model and now comes with a SEN (Sony Entertainment Network) button above the direction pad and a home button below. The menu system is different from the higher-end models' in that it's a simple white-on-transparent-black affair, while the other TVs feature the more sophisticated Sony XMB (cross media bar). I actually liked the simpler version better.

The remote control is simple yet powerful. Sarah Tew/CNET

"="" bgcolor="#CCCCCC">Key TV features
Display technology LCD LED backlight Edge-lit
Screen finish Matte Remote Standard
Smart TV Yes Internet connection Wireless dongle included
3D technology No 3D glasses included N/A
Refresh rate(s) 120Hz Dejudder (smooth) processing Yes
DLNA-compliant Photo/Music/Video USB Photo/Music/Video

Features
Earlier in 2012 I was quite excited to receive the new Sony HX750: hey, it was the second-best TV in the range at the time, so it should've been good, right? My corresponding disappointment with that TV's performance was, I believe, silently shared by some within the company itself. The Sony engineers I met with later explained that the 750 series should have been an "EX" in designation but was bumped up to HX, as it had 3D.

So, even given the significant price difference between the two, the features of the EX640 are still quite decent. This is an edge-lit LED TV that lacks local dimming, but does come with Sony's MotionFlow XR 240 engine. While that number may lead you to believe this is a 240Hz TV, the native panel refresh rate is actually 120Hz.

As I mentioned, the EX640 misses out on 3D playback, but do you really care?

The Sony Entertainment Network is an optional Smart TV interface that provides access to music and video. Sarah Tew/CNET

Smart TV: The XMB interface is only offered on high-end TVs this year, but I didn't miss it because the simpler menus of the EX640 are even easier to use. The most-used apps are still within easy reach on the Menu page, and don't require booting into a new interface. From here you can access the big three: Amazon Instant, Hulu, and Netflix (Sony doesn't support Vudu). Of course, there is also the SEN (Sony Entertainment Network), should you also want access to the company's extensive movie and music offerings. Unfortunately we found that opening it was a very sluggish process -- the SEN interface took up to a minute to load.

For a full listing of Sony's Smart TV services, check out our super comparison.

The menu is simple but provides easy access to Netflix and Hulu. Sarah Tew/CNET

Picture settings: For a midrange television the EX640 offers a good range of picture settings, even if the separate Scene modes are a bit buried in the menus. Unusually I found that the often-excellent Cinema scene mode wasn't as flexible as General, and hid access to the grayscale adjustments necessary for a good calibration.

Connectivity: For a TV under $1,000, the Sony actually offers a decent number of connections, with four HDMI inputs, two composite ports, a single component, and two USB inputs. Be aware that you'll need to use one of those USB ports for the included wireless dongle.

Picture quality

For the price, the Sony EX640 puts in a good performance. While the Vizio M3D0KD is a better TV overall, the Sony delivers a tidy picture with better-than-average black levels. Color depth and saturation are excellent, even if some others are able to deliver more vivid tones. Shadow detail isn't as fine as on other TVs we compared, but the trade-off of an inkier background is worth some loss of fidelity in murkier areas. The TV also showed some issues in the uniformity department, where I detected some uneven backlighting and dirty-screen effect, but it wasn't terrible.

Click the image at right to see the picture settings used in the review and to read more about how this TV's picture controls worked during calibration.

"="" bgcolor="#CCCCCC">Comparison models (details)
Sony KDL-55HX750 55 inch, edge-lit LCD
Vizio M3D550KD 55-inch, edge-lit with local dimming
Sony KDL-55HX750 55-inch, edge-lit LCD
Samsung UN60ES6500 60-inch, edge-lit LCD
Sharp LC-60LE640U 60-inch, edge-lit LCD
Panasonic TC-P55ST50 65-inch plasma

Black level: In bright scenes, it's hard to tell the difference between most well-set-up TVs, but give them a challenging dark scene like "Creation" (chapter 4) from "The Tree of Life," and differences leap to the eye. This scene is quite difficult for LCDs in particular because it involves colored wisps moving against a black background. The EX640 was no exception, showing lighter black levels than the Vizio and the ST50, but it outdid the Samsung ES6500 and the HX750 and looked very similar to the Sharp.

One strike against the Sony was its slightly less-than-perfect rendering of shadows. After the Romulan spaceship passes at the start of chapter 8 in "Star Trek," you see the antagonist, Nero, lying on a green surface. On the other TVs you could see more of the green pattern in Nero's shadow, but on the Sony EX640 it was a little smudged, though at least it was darker.

Color accuracy: While it's not possible to dial in color on a Sony to the extent you can on an LG or Samsung, the color reproduction of the EX640 was quite respectable. Whether it was the deep greens of the trees and baby nursery in "The Tree of Life" or the child's subtle blue jumpsuit, the colors of the Sony seemed more natural than most of its competitors', with the exception of skin tones, which looked a little bluer than on the other sets. The Samsung E6500 was better in terms of skin tone, with a much rosier, healthier-looking -- though still emotionally depressed -- Brad Pitt. Overall, I found that while it didn't show the most accurate color, the Sony was better than most in the more important area of color saturation.

Video processing: Sony has built itself a fine reputation on its video processing and the EX640 continues the company's good work. The TV was able to play back our 24p test scene from "I Am Legend" without any trace of judder, and it also passed our synthetic 1080i deinterlacing test as well.

As I'd expect from a 120Hz TV, the EX640 achieved around 600 lines of moving resolution. As usual to get it to do so meant activating one of its smoothing (dejudder) settings, but I preferred to leave those off.

Uniformity: Perched between the Samsung ES6500 and the Sony HX750, the EX640 was the best of the three in terms of uniformity. The other two TVs had some real issues with backlight clouding and spotlighting in the corners, and while the EX640 was better, it wasn't immune to these problems. There was some spotlighting of the backlight, but it wasn't as noticeable as on the other two. If you want immunity from these problems, look to the Panasonic ST50 plasma or the Vizio M3D0KD with their gorgeous black screens.

One issue that the TV did exhibit was "dirty-screen effect," whereby the backlight structure was visible as darker vertical lines on gray or white screens. If you watch a lot of ice hockey, you might find this distracting.

Off-axis viewing of the EX640 showed a desaturation of color and an even greater blueness to blacks, but this is a common problem of LCDs -- especially at this price.

Bright lighting: Tradionally LCDs perform at their best when in a lit room, but the Sony did have some issues. In a lit room, a black scene looked off-blue in the corners, but the EX640 wasn't alone here: it was the same with the HX750 and Samsung 6500. If you want true black, then you need to go for the Vizio M3D. The Sony has a semimatte finish and wasn't particularly reflective -- about the same level as the other TVs.

Geek Box: Test Result Score
Black luminance (0%) 0.0139 Average
Avg. gamma 2.1597 Good
Near-black x/y (5%) 0.2705/0.2679 Poor
Dark gray x/y (20%) 0.3141/0.3315 Good
Bright gray x/y (70%) 0.3125/0.327 Good
Before avg. color temp. 10034.9337 Poor
After avg. color temp. 6479.0542 Good
Red lum. error (de94_L) 2.9833 Average
Green lum. error (de94_L) 1.2529 Good
Blue lum. error (de94_L) 5.8093 Poor
Cyan hue x/y 0.2308/0.3366 Average
Magenta hue x/y 0.321/0.1439 Good
Yellow hue x/y 0.4322/0.4954 Poor
1080p/24 Cadence (IAL) Pass Good
1080i Deinterlacing (film) Pass Good
Motion resolution (max) 600 Average
Motion resolution (dejudder off) 320 Poor
PC input resolution (VGA) 1,920x1,080 Good

Sony Kdl 46ex640

sony-internet-tv-kdl-46ex640-46-bravia-ex640-series-led-tv-1080p-fullhd-edge-lit-local-dimming-black.jpg
6.7

Sony KDL-EX640

Score Breakdown

Design 7Features 7Performance 6Value 7
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