
I’ll be honest, any technology with “quantum” in its name or description, I’m for. I hate cabbage, but if you called it “Quantum Cabbage” I’d probably eat it. I hate Michael Bay movies, but if he started calling himself Quantum Bay, I’d probably watch them. And if you told me about a technology for TVs with Quantum in its name, I’d be all over it.
Hey, wait, this TV has a technology in it called “Quantum” and it’s a real thing, not just marketing. It’s a real thing called “quantum dots” and if that’s not cool I don’t know what is.
Quantum dots, LEDs, lots of hertz, and more in this full review of the 55-inch KDL-55W900A from Sony.
Dig me some dots
Quantum dots are nanocrystals (quite literally, tiny crystals), that emit a certain wavelength of light when given some energy. If you’ve ever hit a tuning fork (or know what one is), it’s basically the same idea. You hit the fork, giving it energy, and it rings a specific frequency. But instead of a frequency you can hear, a QD “rings” a frequency you can see.
What’s interesting for us is you can get QDs to emit frequencies conducive to video production, with the primary colors like red and green.
If you want more info, I did a whole article on them for CNET appropriately titled What are quantum dots?
Tri… to make more sense
All “LED” TVs are really just LCDs that use LEDs as their backlight. By the same marketing logic, it’s actually surprising Sony’s not calling these “Quantum Dot” TVs. They’re not, they’re LCDs that use Quantum Dots, but that logic rarely makes it to the marketing side of things.
True QD TVs are on the horizon, but for now, the KDL-55W900A uses hybrid LED/QD edgelighting for its light source. A blue LED emits blue light. Some of this blue light excites red and green QDs. These three together give you the primary colors necessary to make an image.
Potentially, this can have some color fidelity benefits. Almost all LED LCDs use “white” LEDs to create light. This “white” LED is actually a blue LED coated with a yellow phosphor. The subpixels on the LCD filter this into red, green, and blue. There’s technically some wasted energy there, given that the yellow phosphor is creating more “colors” than the color-filtered sub-pixels are letting escape to your eye.
With QD and the hybrid LED/QD method, you’re just getting specific red, green, and blue. Using specific red, green, and blue LEDs would largely have the same benefits, but that’s rarely used. Sony last used that method with their Triluminos backlighting from a few years ago. This new LED/QD hybrid has the same name.
A picture, they say, is worth several words, so here is the spectrum of the light created by the LED/QD lighting in the KDL-55W900A:
This is what the TV is doing when it’s creating “white” light at approximately 6500 Kelvin.
For comparison, here’s what the Seiki SE50UY04’s spectrum looks like, doing the same thing:
TeeVee
While a cool technology, the key is if it looks good in a TV, and by extension, if the TV is any good.
The KDL-55W900A is a 1080p 55-inch LCD, with a 240 Hz refresh rate. It’s just below the XBR in Sony’s TV hierarchy. As you’d expect, that means it comes with all the bells and whistles: web streaming, pretty GUI, 3D (active), edge-lit local dimming, NFC/Miracast, MHL, and so on.
Streaming options include Netflix, Hulu Plus, Vudu, Pandora, and also Sony’s own Video Unlimited and Music Unlimited. Sony is one of the few to also offer Amazon Instant Video. The KDL-55W900A is one of the few TVs where an external streaming box is largely unnecessary.
Power consumption is on the low side of the Energy Guide rating, at an estimated $27 a year.
The remote is a pretty basic affair, and seems hardly fitting for a $2,300 television. The menu system, though, makes up for it. It’s a beautiful picture-based system that looks far more like what a 2013 television should have (hint, hint, Samsung and Panasonic).
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Perform(ance)
After adjusting picture controls, and the barest of calibration (it’s pretty close to spot-on out of the box), I sat down to watch some TV. Through a variety of movies and TV shows, a few things about the KDL-55W900A came clear.
First thing, the color is definitely interesting. As you can see from the measurements, the color points are all pretty accurate. There’s more to it than that, it seems. I’ve reviewed plenty of displays with accurate colors, some even more accurate than these. There’s a richness, a naturalness to the color that many other displays lack. Is this due to the quantum dots? Hard to say. I had all the color “enhancement” options turned off, so it wasn’t some Sony oversaturation nonsense. I’ve found with projectors that use separate red, green, and blue LEDs, that the color is somehow a little more realistic. One TV engineer I spoke to about this effect equated it to “painting with purer paint.” Perhaps that’s it, though it’s interesting given that the light still has to pass through color filters, just like any other LCD. Regardless, the color is vibrantly gorgeous.
As far as contrast ratio goes, it’s hard to get an accurate measurement, as even with all the dynamic backlighting effects turned off, it still dims when presented with a black image. I tried to fool it a bit by sending a small, low IRE window. This kept the LEDs active, though it’s not the most accurate test either. In such a configuration, the native contrast ratio was around 4,000:1. This seems a tad high, as in another test I got as low as 903:1 (which, to be clear, is much lower than what it looks like). I’ll try some different images on screen and see if I can get a more accurate reading and update if I get anything definitive.
On top of what the panel itself is doing (whatever its doing), Sony does a great job with their local dimming, even if it is edge-lit local dimming. With most scenes, there’s a lot of contrast between the brightest part of the image, and the darkest, supplying a lot of “pop.” Where the Sony stumbles is with mixed-content scenes, like an image that’s mostly dark, but with some bright areas. An example of this might be a car driving at night. The car interior is dark, the surroundings are dark, but the road under the headlights is bright. Here, the dark areas of the image are a little washed out. The opposite is true as well. A bright scene with some dark areas (like a dark jacket on a bright day), washes out the jacket. So it looks good, but since this year we’ve seen some displays with some ridiculous native contrast ratios, it’s not quite up to those levels. Definitely better than most edge-lit LED LCDs I’ve reviewed.
That the KDL-55W900A is bright goes without saying. I got 104.1 foot-lamberts at full throttle, which should be plenty for anyone.
Normally detail isn’t something I discuss much, given it’s a 1080p TV, you’re feeding it a digital 1080p signal, so it should be bit-perfect. The KDL-55W900A is, but it has some detail-enhancement features that aren’t just ticks on a marketing sheet. I’d played around with some of these features with the VPL-HW50ES projector, and found the results to be quite impressive. The KDL-55W900A has a multitude of settings for the “Reality Creation,” allowing you to fine tune how much apparent detail it adds, along with how much Noise Filtering (basically grain reduction) you want. I was able to find a setting that I actually liked better than “off” which is my go-to mode for pretty much all picture “enhancing.”
And on many shots and scenes, it looks incredibly detailed. Closeups of faces was a big one, with individual whiskers and wrinkles leaping out to such a degree that I’d imagine the actor/actress would be mortified. Textures in clothing is another one, where you see a lot of detail.
However, like all LCDs, this additional detail largely gets lost as soon as the faces or camera movies. However, it’s not nearly as noticeable as many other LCDs I’ve seen. There are multiple settings for MotionFlow, Sony’s frame interpolation engine.
Black field uniformity is excellent, with only a slight increase in brightness towards the edges. This is with a totally black image. If there’s anything on screen (like credits) uniformity isn’t quite as good, and there’s more light visible on the sides. Still, far better than other edge-lit LCDs I’ve seen. White uniformity is also very good, with only a slight dip in brightness along the sides.
Motion resolution on this 240 Hz LCD is decent. Without any of the MotionFlow enhancements, I got about 500 lines (pph). The same in the True Cinema mode. Clear Plus mode also had perfect motion resolution, but like all the following modes, can result in the dreaded Soap Opera Effect. Clear mode isn’t quite as good as Clear Plus, but better than Standard and Smooth, both of which had about 900 lines (pph). The Clear, Clear Plus, Standard and Smooth modes all had some processing artifacts in the vertical lines on the test pattern.
The Impulse mode had perfect motion resolution. It’s a black-frame insertion mode that seriously limits light output, and resulted in somewhat noticeable flicker with bright objects. However, once you get used to the dimmer image, I found this mode to look quite good. Add in the detail enhancements from the Reality Creation and I found it to be some of the best the 55W900A looked in my testing: Excellent color, tons of detail, decent contrast. I will say, though, other modes might look better to other people (people who, perhaps, don’t mind the Soap Opera Effect and/or want a brighter image).
The 3D performance is only OK. The lightweight RF glasses are fine, but there’s not a lot of depth to the image, and there’s a fair amount of crosstalk. It helps that the image is so bright, though.
Input lag in Cinema Mode, however, is flat out terrible: 102.6 milliseconds. This is significantly higher than even the already slow Panasonic ST60 (73.6ms). In Game Mode, however, is among the fastest TVs you can buy: 18.9ms. Game Mode locks you out of a lot of picture settings, but for that kind of performance, it’s probably worth it.
Off-axis performance isn’t as bad as some LCDs I’ve reviewed. Moving away from center definitely decreases the contrast, but it’s not as severe as I’ve seen.
Conclusion
The KDL-55W900A is an excellent LED LCD. I’m disappointed Sony chose to go with their own “Triluminos” branding instead of the quantumly cooler “Quantum Dots.” Like most high-end LED LCDs, though, it’s pricy. A similarly sized TC-P55ST60 Panasonic plasma, which we gave 5/5 hearts, is $1,000 cheaper.
For some, though, plasmas are a no-go. If you’re one of them, and you’ve got the money, the KDL-55W900A is a gorgeous television, with tons of features, beautiful color, lots of detail, and, you know, that whole quantum dot thing.
As such, HDGuru awards the $2,300 KDL-55W900A 4.5/5 hearts.
Geoff Morrison @TechWriterGeoff
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