Sony KDL-46NX720 LED LCD 3D HDTV Review

3D Effect & Experience

Overall, the 3D effect given by the KDL-46NX720 isn't too bad, but it isn't all that great either. We've yet to see an LCD TV really compete with plasma screens in this regard, and the Sony Bravia KDL-46NX720 is no different: it struggles with motion, making a stuttery image that just looks mediocre. It's no secret that we haven't really come around on 3D TVs yet, as they don't seem to perform all that well so far, but we'd rather pay less for a TV that performs better without 3D.

3D Black & White

It's not terribly surprising that the originally wide contrast ratio of the KDL-46NX720 dropped significantly when viewed through 3D glasses, as you're essentially wearing sunglasses while watching TV. As you can see, the peak brightness dropped to an incredibly low 29.2 cd/m2, thus cutting the contrast ratio to 490:1, which is actually pretty good for a 3D TV.

3D Color

Much like its performance in 2D, the 3D color performance of the KDL-46NX720 is poor, with a giant warming problem that makes a noticeably bad color temperature error throughout the entire range of signal intensity.

The RGB curves for the KDL-46NX720's 3D mode were beautiful for a 3D response. Though the blue was dark for a majority of the range of signal intensities, it's not surprising given the poor performance it gave us in the regular 2D testing. Overall, the lines were smooth and relatively uniform, so you can expect decent color performance out of your set.

The 3D color gamut is also good, showing only a tiny shift in color values in comparison to the 2D responses we measured earlier. This is a pretty good performance, all things considered.

3D Crosstalk

3D pictures on televisions (with active shutter glasses) work by sending two separate images, one to each eye. When we talk about crosstalk, we're referring to the propensity for one image leaking into the field of view of the other, meaning part of the image intended for one eye showing up in the other. Active shutter glasses have varying degrees of success in minimizing this, but it's almost never perfect, and can be the single biggest contributor to a breakdown in the 3D effect.

The KDL-46NX720 had minor issues with crosstalk, with black-on-white and white-on-black giving us the worst problems. Overall, it's not a bad performance, but 3D TV technology has a long way to go before crosstalk is brought down to a point where it's hardly noticeable.

3D Glasses

Perhaps the greatest argument for buyers of 3D screens against active-shutter systems is how prohibitively expensive each pair of 3D glasses is. Surprisingly enough, the cost of Sony's active-shutter glasses has come down a bit, and right now they're retailing for about $70 on Amazon, which is a load cheaper than what they have been in the past. They still won't catch polarized glasses for a long time, but at least some small gesture has been made in this regard. Still, do you really want to shell out $70 a pair for 3D glasses when the set only comes with one? If you have the money, by all means go for it, but these things are expensive.

Sony's 3D glasses themselves aren't too cumbersome, but they're certainly a ways off from being comfortable, especially for those of us who wear prescription glasses. Also, there's really not much you can do to customize the fit or allow for a differently-sized head.