Sony Bravia KDL-BX420 review: Sony Bravia KDL-BX420

Sony Bravia KDL-BX420

David Katzmaier

David Katzmaier

Editorial Director -- TVs and streaming

David has reviewed TVs, streaming services, streaming devices and home entertainment gear at CNET since 2002. He is an ISF certified, NIST trained calibrator and developed CNET's TV test procedure himself. Previously David wrote reviews and features for Sound & Vision magazine and eTown.com. He is known to two people on Twitter as "The Cormac McCarthy of consumer electronics."

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3 min read


Sony Bravia KDL-BX420

The Good

The inexpensive <b>Sony KDL-BX420</b> series evinced good performance for an entry-level non-LED-TV, with deep-enough black levels and accurate color in mid-bright areas. It also, surprisingly for a 60Hz TV, handled 1080p/24 cadence properly, and its matte screen is a boon in bright rooms. Its styling is clean and its remote is among the best in its class.

The Bad

The BX420 only has two HDMI inputs when most of its competitors have three or four. Its color was too blue in dark areas and too red in bright areas and its screen showed brighter corners.

The Bottom Line

If you don't expect the world from the entry-level Sony KDL-BX420 LCD, its picture quality may be a pleasant surprise.

By this time next year companies like Sony might not even sell TVs like the KDL-BX420 series. The CCFL (cold-cathode fluorescent) backlight that illuminates this TV's LCD panel is slowly going extinct, replaced especially in larger screen sizes by LEDs packed into razor-thin cabinets that can generate more light from less power. They can also generate higher profits. The BX420 is Sony's least expensive 1080p TV for 2011, and it's a very good value. The picture quality isn't up to the best non-LED models we've seen, like Samsung's more expensive LND630, but we noticed no major problems and a couple of surprising strengths. We wouldn't recommend it for budget videophiles, but casual viewers who don't want to pay more for LED will find plenty to like about the Sony KDL-BX420.

Series information: We performed a hands-on evaluation of the 40-inch KDL-40BX420, 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-32BX420 32 inches
Sony KDL-40BX420 (reviewed) 40 inches
Sony KDL-46BX420 46 inches


Sony keeps the BX420's design clean and entirely black.

"="" bgcolor="#CCCCCC">Design highlights
Panel depth 3.75 inches Bezel width 2 inches
Single-plane face No Swivel stand No

Sony eschews the transparent edging, color accents and swivel stands of Samsung and LG in favor of unadorned glossy black on a low-profile, swivel-free base. We appreciate the clean look but, as expected at this level, it's nothing special.

"="" bgcolor="#CCCCCC">Remote control and menus
Remote size (LxW) 8.6x1.7 inches QWERTY keyboardNo
Illuminated keys No IR device control No
Menu item explanations No Onscreen manual No

The basic Sony remote is an ergonomic winner despite its petite size. A sensible number of buttons are arranged into logical areas differentiated by size, color and shape, centered on a big Home key below the cursor control. The menus are similarly simple and satisfying, managing to place plenty of choices onscreen without seeming overwhelming.

A separate options menu gives quick access to most of the TV's settings.


"="" bgcolor="#CCCCCC">Key TV features
Display technology LCD LED backlight N/A
3D technology N/A 3D glasses included ">N/A
Screen finish Matte Internet connection No
Refresh rate(s) 60Hz Dejudder (smooth) processing No
DLNA compliant No USB Photo/Music/Video

The most notable extra is the Sony's ability to play back music, photo, and video files from attached USB drives. Unlike the Samsung LND550 series, the BX450 lacks an Ethernet port, so it can't do the same via DLNA over a home network.

"="" bgcolor="#CCCCCC">Picture settings
Adjustable picture modes 9 Fine dejudder control N/A
Color temperature presets 4 Fine color temperature control 2 points
Gamma presets 7 Color management system No

In addition to the three adjustable picture modes available under the General setting, there are (confusingly) six more under Scene. A seventh, called Auto, can't be adjusted. That's plenty of presets but only Custom and Standard allows access to advanced settings like detailed color temperature controls and gamma. Unlike LG with its LK450 series, Sony doesn't provide 10-point color controls or a color management system.

Fine color temperature control is welcome, but it's not as fine as LG's.

"="" bgcolor="#CCCCCC">Connectivity
HDMI inputs 2 back Component video inputs 1 back
Composite video input(s) 1 back, 1 side VGA-style PC input(s) 1 back
USB port 1 side Ethernet (LAN) port No

Compared with the Samsung, Vizio, and LGs at its level, which offer at least three HDMI ports, the BX420's two-port offering is one of its biggest weaknesses. Two HDMI might be enough for the most basic systems, but to add something beyond a cable box and a game console--say, perhaps, a Roku or even a temporary camcorder or laptop PC connection--you'll need to get an external HDMI switch.

Two HDMI inputs is a paltry amount by even entry-level standards these days.

While the Sony BX420 doesn't do anything particularly well from a picture quality standpoint, it also, surprisingly for an entry-level LCD, doesn't do much badly. Its worst offense is color inaccuracy in dark areas and imperfect screen uniformity, but its black levels were decent and it actually handled 1080p/24 cadence--something we didn't expect from a 60Hz TV. Overall its picture deserves the same score of 6 we gave to Sony's EX720 LED-based model, which costs hundreds more. We'd give the BX420, with its more accurate color and better processing, a slight edge over the Samsung LND550 with its better black levels and uniformity, but the two are neck-and-neck overall.

We selected Cinema as the best picture setting for dark-room viewing out of the box, although it measured too red with dim light output and dark gamma. With the controls in Custom we were able to fix quite a few of those issues during calibration, although the reddish cast crept into very bright areas nonetheless, and dark areas were still quite blue. For image quality tests we checked out "Harry Potter and the Deathly Hallows: Part 1" on Blu-ray.

"="" bgcolor="#CCCCCC">Comparison models (details)
Samsung LN40D550 40-inch LCD
LG 42LK450 42-inch LCD
Vizio E3D420VX 42-inch LCD
Samsung LN46D630 46-inch LCD
Sony KDL-46EX720 46-inch LED-based LCD
Panasonic TC-P50ST30 50-inch plasma

Black level: The darkened hallway at the end of Chapter 9 provided some good comparison examples, from the letterbox bars to the shadows along the black walls. The BX420 landed about in middle of our pack, delivering a deeper shade of black than either the LG or the Vizio, but falling short of the Samsungs and the Panasonic. Interestingly the significantly more expensive Sony EX720 was visually indistinguishable from the BX420 in terms of the two TVs' depth of black.

Details in those shadows, for example the dark pants and shirt of Hermione and the painting on the wall, appeared relatively realistic and more natural than on the Vizio or LG, albeit not as good as the Samsungs or Panasonic.

Color accuracy: Despite its relatively poor measurements the BX420's color subjectively looked better than its direct competitors'. The skin tones of Harry and Hermione in Chapter 10, for example, both looked natural enough and well-saturated, without any of the paleness we saw on the Samsung LND550 or the bluish tint of the EX720. While the LG and Vizio were both technically more accurate, we preferred colors on the BX420 since (thanks to its better black levels) it looked punchier and more saturated. On the other hand the more expensive LND630 and Panasonic plasma looked better than the Sony.

The near-black and black shades on the BX420 were tinged with more blue than any of the other comparison TVs aside from the EX720, which was the worst in this area.

Video processing: We were surprised that the Sony, a 60Hz TV, passed our 1080p/24 test by preserving the cadence of film. We're guessing the TV isn't performing 2:3 pull-down processing when it detects a 1080p/24 source, which may lead to some artifacts, but we didn't notice any during our testing. That's why we recommend that BX420 owners use the 1080p/24 setting on their Blu-ray players.

Uniformity: The screen of the BX420 sample we reviewed was not quite as uniform as those of the other non-LED sets in our lineup. Its upper right corner showed a brighter spot and its upper left corner had another, albeit slightly dimmer; both were easily visible in the letterbox bars of "Potter."

When seen from off-angle it performed better than the Vizios at keeping its black level preserved, but not as well as the Samsungs, and we detected more reddish and bluish discoloration than on the other displays.

Bright lighting: The Sony's matte screen serves it well in bright rooms where lights, windows and bright objects cause reflections. Such objects appeared dimmer and much less distinct, and thus less distracting, then they did on the Panasonic plasma, for example, and black levels were also preserved better. The rest of the sets in the lineup also have matte screens, and in general they all performed equally well in this category.

PC: The BX420 performed worse as a big PC monitor via VGA than most LCDs we've tested. Despite handling the full resolution of 1,920x1080 pixels, it evinced softness in text and other detailed areas that no adjustment we tried could cure. PC sources via HDMI looked fine, however.

Power consumption: Although it qualifies as a "Power Saver" and uses a negligible amount of electricity, the BX420 isn't quite as efficient as the larger Samsung D630.

Test Result Score
Black luminance (0%) 0.0126 Average
Avg. gamma 2.2176 Good
Near-black x/y (5%) 0.2484/0.2447 Poor
Dark gray x/y (20%) 0.3127/0.3299 Good
Bright gray x/y (70%) 0.3124/0.328 Good
Before avg. color temp. 6328 Average
After avg. color temp. 6386 Average
Red lum. error (de94_L) 4.0271 Poor
Green lum. error (de94_L) 4.5893 Poor
Blue lum. error (de94_L) 4.4517 Poor
Cyan hue x/y 0.2212/0.3317 Good
Magenta hue x/y 0.3393/0.1586 Poor
Yellow hue x/y 0.4213/0.496 Good
1080p/24 Cadence (IAL) Pass Good
1080i De-interlacing (film) Pass Good
Motion resolution (max) 300 Poor
Motion resolution (dejudder off) n/a n/a
PC input resolution (VGA) 1920x1080 Poor

Juice box
Sony KDL-40BX420 Picture settings
Default Calibrated Power save
Picture on (watts) 117.83 77.59 54.2
Picture on (watts/sq. inch) 0.17 0.11 0.08
Standby (watts) 0.111 0.111 0.111
Cost per year $25.92 $17.10 $11.97
Score (considering size) Good
Score (overall) Good

Annual energy consumption cost after calibration

Sony KDL-40BX420 CNET review calibration results

(Read more about how we test TVs.)


Sony Bravia KDL-BX420

Score Breakdown

Design 7Features 6Performance 6