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Sony Bravia KDL-NX720 review:

Sony Bravia KDL-NX720

Sony divides its picture presets into two groups: General (with three choices) and Scene Select (with eight, including Auto). Two of the Scenes, Cinema and Game, have two separate modes of their own as well. The total number of adjustable modes crests the double digits, which should be enough for just about everybody.

The available adjustments themselves are somewhat sparse by today's standards. The company didn't add the option to adjust dejudder processing beyond the four presets, and unlike some competitors it doesn't offer a 10-point white-balance control or color management system. The local dimming function comes in two strengths, Low and Standard; the latter provides the best black levels and is what we used for critical viewing.

HDMI inputs 4 Component video inputs 1
Composite video input(s) 1 VGA-style PC input(s) 1
USB port 2 Ethernet (LAN) port Yes
Other: Headphone jack; RS-232 port

The KDL-NX720's input area, as on many thin TVs, relies on sideways- and downward-facing ports as well as a breakout cable for component or composite video (you can connect one or the other, but not both). The headphone output is welcome and rare among big TVs.

Along with 4 HDMI and 2 USB, the jack pack's best feature is a headphone port.

Deep black levels are the Sony KDL-NX720's main strength, and although it scored the same 7 in this category as the LG LW5600 and the Samsung UND6400 series, if we had to choose one of the three based purely on performance, it would be the Sony by a nose. Color and video processing are both very good, as is screen uniformity. On the other hand we wish we could enjoy those black levels from wider viewing angles, and anyone who cares about 3D will want to look elsewhere.

Among the NX720's numerous picture presets we ended up preferring Cinema for dark-room critical viewing, but it did exhibit dark gamma in the middle areas and a too-bright overall image for dark rooms. Our calibration using Custom improved gamma quite a bit and kept the excellent grayscale. We'd have liked a 10-point grayscale system to further hone both, as well as color management to dial in the primaries and secondaries a bit closer to spec, but overall the NX720 set up nicely. For our image quality tests we employed the lineup below and watched "The Green Hornet" on Blu-ray.

Comparison models (details)
LG 47LW5600 47-inch edge-lit local-dimming LED
Samsung UN55D8000 55-inch edge-lit local-dimming LED
Toshiba 47TL515U 47-inch edge-lit local-dimming LED
Samsung UN46D6400 46-inch edge-lit LED
Sony XBR-55HX929 55-inch LED with full-array local dimming
Samsung PN59D8000 59-inch plasma
Pioneer PRO-111FD 50-inch plasma

Black level: All told the NX720 delivered one of the deepest shades of black we've seen from any edge-lit TV, outdoing most of the other LCDs in our lineup and effectively tying the superb Samsung plasma in this department. Only the local-dimming HX929 and the Kuro delivered a consistently deeper black, and although the Samsung UND6400 and LG LW5600 came closest to the NX720, the Sony was still visibly darker. Evidence of those black levels was most obvious in the black letterbox bars and dark areas, like the sky above the mansion in chapter 4 (23:18).

We did see blooming in some areas, but it was minor. At 10:55, for example, the morning light from a bedroom window spilled over into the left of the bottom letterbox bar somewhat, and at 12:10 light from an open limo window again brightened a bar, this time on the lower left. Neither case was egregious, nor any worse than what we saw on the HX929, the LG, and the Toshiba. We didn't notice any major black-level fluctuations as scene brightness varied overall.

Shadow detail on the Sony NX720 was a comparative weakness, falling short of the others aside from the Samsung plasma. The fine near-black detail in the cheek and hair on the severed statue head (23:42), for example, was somewhat obscured. The NX720 also had the annoying habit of turning its backlight completely off during longer fades to black, a propensity it shares with the Samsung UND6400.

Color accuracy: The Sony turned in a very good performance in this area, delivering solid if unspectacular measurements compared with its closest compeditors, the LG and the UND6400. In program material it competed well, however, with accurate skin tones among Britt and the party chicks in chapter 2, and a nice neutral tone to the white walls of The Standard. Compared with the stellar LG and our reference Samsung plasma we noticed a slight reddish or too-warm cast in some scenes, like the room of the wake-up at 9:40, and a bit of blue in skin tones during bright scenes, but these issues weren't very noticeable, especially outside of a side-by-side comparison.

Near-black on the NX720 was not quite as neutral as we saw on the LG, the plasmas, or the HX929, but was still free of the overt blue tinge we saw on the Samsung LCDs and the Toshiba. Its deeper black levels definitely help in this department. They also, as usual, contribute to the NX720's very good saturation, which results in rich, lifelike color in brighter scenes.

Video processing: With Motion Flow set to the Off position, the NX720 correctly handled 1080p/24 film cadence. All of the other settings introduced some degree of smoothing (dejudder), although Clear came closest to Off, preserving a good deal of judder and keeping smoothness to a relatively low, albeit still easily discernable, level. As usual we wished for a Custom implementation similar to what Samsung provides, as opposed to having to select from presets.

Two of those presets, Clear and Clear Plus, use backlight scanning for maximum motion resolution. The other two, Standard and Smooth, do not, and come in at around 900 lines. As usual we couldn't tell the difference in normal program material between any of these settings, including Off.

Like the HX929 but unlike most other TVs we've tested, the NX720 failed our 1080i deinterlacing test, so you may see some minor artifacts in 1080i film-based material.

Uniformity: Our NX720 review sample, unlike most edge-lit LCDs we've tested, didn't show any major brightness variations across its screen. Looking at test patterns we detected slightly brighter edges along the bottom, but the difference wasn't visible in program material.

From off-angle, on the other hand, the NX720 lost black level and color fidelity quite quickly. From one couch cushion to either side of the sweet spot at our 8.5-foot seating distance, we saw the outer edge of the letterbox bar brighten significantly compared with the near edge. Areas of blooming also became, as usual, more apparent the farther we moved off-angle. On the other hand the LG and Toshiba were even worse from off-angle, the XBR929 about the same, and both Samsungs marginally better.

Bright lighting: The Sony's glossy screen was a liability when bright lights and objects reflected therein; those reflections appeared brighter than on any other set in our lineup with the exception of the HX929 (which has the same screen finish as far as we can tell). The Sony did preserve black levels quite well, however, outdoing the others in this department. As usual, the matte-screened LCDs from LG and Toshiba, as well as Sony's own EX720, looked best overall under the lights.

PC: The NX720 performed as well as we'd expect from a 1080p LCD-based TV with PC sources, resolving every line of a 1,920x1,080-pixel-resolution source via VGA with no edge enhancement or softness in text.

3D: Like the HX929, the NX720 had its difficulties with 3D and, if anything, it performed worse than its more expensive brother. For the testing below we used the 3D Blu-ray version of "The Green Hornet" and the same comparison lineup as above.

First off we did notice visible flicker throughout the image, especially in brighter areas like the explosion at 7:21 and the walls of the garage at 8:33, when we turned off the MotionFlow processing. For whatever reason the flicker wasn't as bad as on the HX929, but it was still annoying and rendered the image unwatchable to our eyes.

With the HX929 our preferred solution was to turn on MotionFlow and set it to Standard, which eliminated flicker but introduced some smoothing (dejudder)--a tolerable if not ideal tradeoff. MotionFlow on the NX720 also removed the flicker, but its processing performed much worse in 3D than on the HX929. We saw significant stuttering and hitching with both settings (Standard and Smooth; both "Clear" options are disabled for 3D), especially in scene pans such as the hilarious fast-motion garage make-out sequence at 8:33. If we owned an NX720 we'd probably still watch 3D in Standard to avoid the flicker, but we wouldn't qualify that stutter as tolerable.

Both Sonys also looked much worse than any of the other sets when we tilted our head slightly to either side. Doing so caused the 3D illusion to disappear and unwatchable crosstalk to set in almost immediately, forcing us to keep our eyes almost completely level relative to the screen. We don't recommend watching 3D with much tilt anyway (when you lie on your side and watch, provided the TV can even handle it, you're likely to experience discomfort after a few minutes), but the Sony's intolerance for even the slightest tilt is an issue.

We saw neither flicker nor extreme intolerance to head tilts on any of the other active 3D sets. We saw both issues, on the other hand, when viewing 3D on Sony's KDL-46EX720.

We also noticed more crosstalk on the NX720 than on the HX929; for example in the pillars and ceiling of the garage and the exercise bike in the back of the wake-up room (10:17). Crosstalk on the NX720 was worse overall than on the other sets as well, although the UND6400 wasn't much better.

In its favor, and as expected for an LCD, the NX720 was also significantly brighter than any of the plasmas, with ample light output for even bright rooms, and colors looked fine in the default Cinema mode we tested.

Power consumption: We did not test the power consumption of this size in the Sony KDL-NX720 series, but we did test the 55-inch model. For more information, refer to the review of the Sony KDL-55NX720.

Test Result Score
Black luminance (0%) 0.0002 Good
Avg. gamma 2.22 Good
Near-black x/y (5%) 0.3159/0.3321 Good
Dark gray x/y (20%) 0.3142/0.3295 Good
Bright gray x/y (70%) 0.3131/0.3312 Good
Before avg. color temp. 6526 Good
After avg. color temp. 6463 Good
Red lum. error (de94_L) 1.6052 Average
Green lum. error (de94_L) 2.0158 Average
Blue lum. error (de94_L) 2.1467 Average
Cyan hue x/y 0.2338/0.3376 Average
Magenta hue x/y 0.323/0.1497 Good
Yellow hue x/y 0.425/0.5199 Poor
1080p/24 Cadence (IAL) Pass Good
1080i Deinterlacing (film) Fail Poor
Motion resolution (max) 1200 Good
Motion resolution (dejudder off) 400 Poor
PC input resolution (VGA) 1,920x1,080 Good

Sony KDL-55NX720 CNET review calibration results

(Read more about how we test TVs.)

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