The pages of AV history are littered with "here today, gone tomorrow" features only truly memorable for the amount of hype that surounded their launch. We have no doubt, though, that the latest feature on the AV block, high dynamic range (HDR) playback, isn't going anywhere. Which is why we're rather excited by the Sony KD-65ZD9BU.
This is a TV, after all, that's been conceived, designed and manufactured with HDR right at the heart of everything it does. For instance, it's capable of pumping out unprecedented amounts of brightness, outgunning by a few hundred nits even the mighty efforts of Samsung's ground-breaking KS9500 SUHD TVs.
Even more excitingly, it delivers its huge brightness via an LED lighting array positioned directly behind the screen which is driven by the most advanced local dimming system the LCD world has seen to date. Every single one of its LEDs can have its output adjusted individually, to potentially deliver unfathomable blacks right alongside those unprecedentedly bright whites and retina-searing colours.
Is the Sony ZD9 the best LCD-based 4K HDR TV on the market right now then? It might well be, if you have deep pockets: the 65-inch model on review here costs £3,999.
Sony ZD9 4K HDR TV review: Bettering the competition
There are other TVs out there, of course, that use direct LED lighting and local dimming systems. Panasonic's DX902 TVs can even also control each LED light individually. Look to the alternative tech, OLED, and the LG E6 is also outstanding, albeit less bright in the HDR stakes.
However, the ZD9 has a couple of extra tricks up its sleeve compared to the Panasonic: Calibrated Beam technology, and X-Tended Dynamic Range. The first of these enables the TV to focus multiple LEDs as a group on particularly bright image element, to boost its on-screen intensity. The second, X-Tended Dynamic Range, allows Sony to redirect the power available to the 65ZD9's screen away from where it's not needed (dark image areas) to where it is.
The extra brightness and contrast the ZD9 is designed to deliver should also feed into its colour performance, making it easier to achieve the expanded colour spectrums that HDR sources like Ultra HD Blu-ray and, now, Netflix and Amazon also deliver. The 65ZD9 also beneftis from Sony's Triluminos technology, which has for the last two or three Sony TV generations done an excellent job of boosting colour satuation.
Sony KD-65ZD9BU TV review: Android TV limitations
We know you're keen to find out just how well all of the 65ZD9's intriguing screen technology translates into picture quality, but there are few other features to quickly cover first. Kicking off with its Android TV smart system.
We continue to be unconvinced by Android TV, though. It feels old-fashioned and cumbersome thanks to its full-screen presentation, lack of customisation options, and frustratingly sluggish responses. Android does, though, provide a vast library of apps for you to explore, including the 4K and HDR-capable versions of both Netflix and Amazon.
Thankfully Sony has also added YouView support to its UK TVs to get around Android TV's ongoing failure to carry the catch-up apps for all of our main terrestrial broadcasters.
Sony ZD9 4K HDR TV review: Setup
Setting the 65ZD9 up is not a job for the faint hearted. Its brushed aluminium stand is awkward to attach to the TV, and its remote control is a horror show thanks to its use of buttons that sit almost flush with the remote's front edge. It also takes a painful amount of time to get the Android-related features up and running.
It's not all bad news, though. The 65ZD9's picture presets are unusually thoughtful, giving you a number of genuinely useful out-of-the-box presets for both HDR and SDR (standard dynamic range) viewing. Though if you do want to tweak things or even pay a calibrator to do it for you, the 65ZD9 certainly isn't short of fine tuning tools.
Sony ZD9 4K TV review: HDR peaks
Settling down to see what the 65ZD9 can do, the first word that comes to mind is "wow". The brightness the screen is capable of pumping out is breath-taking, for instance, delivering an instant impact with HDR sources that can only be described as transformational. HDR's killer brightness peaks look more explosive than we've seen them look before, even on Samsung's KS9500 series, while UHD Blu-ray's wider colour gamuts look both explosively vibrant but also beautifully subtle thanks to the way the extreme brightness brings out even the tiniest tonal differences.
It's a big relief, too, to see the 65ZD9's HDR pictures looking entirely free of the colour striping issues that have hindered a number of rival HDR sets this year - including Samsung's KS9500s.
Crucially, though, the 65ZD9 doesn't push brightness at the expense of all the other traditionally key aspects of picture quality. In particular, its unique LED backlighting system does a better job than that of any other LCD screen to date of minimising light pollution around HDR highlights when they appear against dark surroundings.
There are none of the vertical bands of light running down the screen you get with edge-lit LCD HDR TVs, and while the set isn't immune to light halos around ultra-bright objects, these halos are both less intense and smaller in scale than those seen on other TVs that use direct LED lighting technology. This is impressive indeed considering the 65ZD9's ground-breaking brightness, and in ensuring that the unwanted side effects of HDR on LCD TVs are less distracting it makes the experience instantly more engaging and immersive. Which is, of course, exactly what HDR is supposed to be.
The 65ZD9 is also jaw-droppingly good at making its 4K resolution count. Its ground breaking light control combines with all those pixels and some stunning colour finesse courtesy of the Triluminos engine and X1 Extreme chipset to deliver pictures of sublime detail, crispness and depth. So much so that pictures often look three dimensional without the need for any pesky glasses.
The sharpness holds up unusually well during sport and action scenes too, thanks to what's arguably the most effective motion processing engine in the TV world right now. The True Cinema processing mode, in particular, does a terrific job of reducing judder and motion blur without making the picture look unnaturally smoothed out or troubled by unwanted digital side effects. This motion clarity makes the 4K experience feel fantastically consistent and emphatic.
Sony KD-65ZD9 review: It does 3D too
The 65ZD9 is the first TV we've tested for an age that also ships with 3D glasses included. Indeed, you get two pairs. Its 3D pictures - delivered using the full resolution active shuttering system - are pretty strong, combining an engaging sense of depth and space with an excellent colour response and plenty of detail.
There can be some fairly noticeable crosstalk ghosting noise around bright 3D objects, but this rears its head fairly rarely by active 3D TV standards.
The main problem with 3D on the ZD9 is how dull it looks compared with the set's spectacular 2D HDR images. So much so that we can imagine many previous 3D fans feeling increasingly reluctant to sacrifice HDR's thrills for 3D's extra depth. It was only a matter of time before 3D was more-or-less killed off.
Sony ZD9 review: Content, what content?
Unfortunately, of course, while the 65ZD9 performs like no TV before with HDR sources, such sources are currently pretty elusive. But fear not, for the 65ZD9 is also a superb performer with standard dynamic range content.
It still produces a lovely blend of colour intensity and subtlety with SDR colours, still serves up an excellent SDR contrast peformance only bettered by LG's OLED TVs, and SDR pictures still look phenomenally detailed.
Even HD sources look something like native 4K thanks to the outstanding ability of Sony's upscaling processing to boost the resolution of non-4K content without exaggerating source noise.
Sony ZD9 TV review: Slim on the sound
Aside from the quirky application of a gold colour to its outside edges, the most eye-catching thing about the 65ZD9's slightly bland design is that it doesn't incorporate any of those spectacular sounding but huge magnetic fluid speakers found on the past two or three generations of Sony flagship TVs. While this may make aesthetic sense, it certainly doesn't do Sony's sound quality any favours.
The biggest issue is that there's hardly any bass. This leaves treble sounding over-exposed and can lead to quite a brittle presentation of loud action scenes - especially if you try to push them to the sort of volume levels many scenes typically benefit from.
To be fair, vocals are always easy to make out and reasonably well-rounded, and the TV is built well enough to avoid issues like speaker crackle or cabinet rattle. If ever a TV deserved to be accompanied by a decent external audio solution where finances permit, however, it's the 65ZD9.
The 65ZD9 is not a perfect TV (if such a thing could ever exist). Its Android smart engine is more of a hindrance than a help, its sound is pretty average, and there's still some evidence of backlight haloing around stand-out HDR objects, despite Sony's exciting new LCD illumination technologies.
None of this, though, stops the 65ZD9 from winning hook, line and sinker when it comes to HDR content though. Its unprecedented combination of colour, brightness, sharpness and contrast is virtually addictive, and undoubtedly adds up to what is simply the most spectacular and convincing next-generation TV picture performance of 2016.
It's a long way from affordable, but if LG's ultra-slim OLED options aren't on your radar and you want the ultra bright peaks that high dynamic range content can offer then, hands down, the ZD9 is the HDR master.