Ultra HD is a massive step up in the amount of pixels on screen, with a resolution that roughly equates to four HD screen's worth of pixels placed in a grid.
As well as offering a big boost in picture clarity due to the increased number of pixels, the era of 4K is also ushering in a number of excellent new TV technologies such as HDR which are combining to offer a big boost in image quality.
The only catch is that just because a TV has a 4K resolution and, perhaps, HDR and wide colour technologies it's not automatically a brilliant TV. In fact, HDR in particular is proving quite a challenge for TVs to get right. So let's try and make your buying decision at least a bit easier with our pick of the best 10 4K TVs you can buy today.
Update: A couple of our top 4K TV picks are seeing some discounts this Black Friday weekend. The Samsung UEKS7000 is currently £350 off at Hughes, the Panasonic Viera 58DX902B is down from £1,999 to £1,799 at John Lewis , and finally the Sony Bravia 65XD9305 has also been discounted by £300 at John Lewis.
No TVs in 2016 deliver pictures more downright spectacular than Samsung's KS9500s. Partly because no other commercially released TVs have ever delivered as much brightness, but also because Samsung has used a high-end backlighting system and a proprietary take on Quantum Dot colour technology to ensure that the emphatic brightness is joined by excellent contrast and explosively rich but also gorgeously nuanced colours.
Push all this technology to the max with today's highest quality sources - especially, the incredible images you can get from the new Ultra HD Blu-ray format - and you'll witness pictures the like of which just haven't been seen on a TV before.
The KS9500s aren't perfect; the push for such extreme contrast from an LCD screen can sometimes cause backlight clouding around very bright objects, and the most accurate Movie preset can cause colour striping with UHD Blu-ray. There's no 3D support either. So extraordinary are the KS9500s' pictures at their best, though, that their flaws become seriously easy to forgive.
For the sort of AV enthusiast who always preferred the contrast and subtlety of now defunct plasma screens to the more brightness focussed charms of LCD, OLED technology has long looked like the next big thing. And LG's stellar OLEDE6 models do nothing to dispel this notion.
This is because it manages to combine OLED's currently unique ability to have every single pixel in its screen produce its own light and colour independent of its neighbours with a substantial leap in brightness versus any previous OLED generation. What's more, this HDR-friendly leap in brightness has been delivered without compromising the remarkable black level reproduction that's OLED's trademark.
LG will need to improve brightness still further if it wants to avoid the loss of detail in really bright HDR areas the OLEDE6 models sometimes fall prey too, but for many AV fans the E6s' freedom from the sort of backlight flaws all LCD TVs suffer with to some extent will prove nigh-on irresistible.
The 75XD9405's huge 75-inch screen serves up a spectacular demonstration of the advantages of having four times as many pixels as you get with an HD TV, adding a sense of scale to 4K's enhanced precision that leaves pictures looking so lifelike it's almost scary. Not that size is by any means the only thing the 75XD9405 has going for it, mind you.
Sony's Triluminos wide colour spectrum technology and a strong contrast performance from its direct (behind the screen) LED lighting system also play their part, delivering both standard and high dynamic range pictures in a balanced and nuanced way that combines with the screen acreage to provide a massively immersive experience.
The 75XD9405 isn't as bright as some rivals and extreme-contrast HDR shots occasionally cause backlight clouding, but if your tastes are more home cinema than TV, the 75XD9405 is currently uniquely qualified for the job.
First, the bad news: The DX802s don't have enough brightness and colour resolution to deliver the maximum HDR experience. You also need to use their Adaptive Backlight setting on its highest level to get a convincing black colour during dark scenes, which can cause occasional backlight stability and clouding.
The good news is that once set up right, the DX802s produce far more spectacular 4K HDR pictures than you've any right to expect for such a reasonably priced TV. There's enough brightness to deliver HDR with plenty of punch backed up by unusually good black levels by affordable LCD TV standards, and colours are reproduced with exceptional finesse. This helps the DX802s deliver plenty of impact from its native 4K resolution too, while the mostly lovely pictures are joined by outstanding sound courtesy of an external sound bar that ships free with the TV.
Finally, the DX802s benefit from a seriously eye-catching design that sees the screen hanging between two easel-style legs.
Despite being much cheaper than the KS9500 range that tops this list, Samsung's KS7000 series still meets the demanding specifications set out by the Ultra HD Premium 'standard'. Which means, essentially, that it's got enough brightness, contrast, colour and resolution to produce an uncompromising high dynamic range performance.
So it is that HDR sources look unprecedentedly dynamic and rich for the KS7000 range's level of the market. The sets also do an emphatic job of getting the maximum impact from their native 4K pixel counts.
The TVs look brilliant with standard dynamic range sources too - though a recent firmware update means that all Samsung's 2016 SUHD TVs now offer a surprisingly effective processing system for upscaling SDR to HDR.
There's no 3D support, and very high contrast HDR images can suffer with fairly obvious signs of backlight striping and clouding. Neither of these issues, though, stop the KS7000 from being a great value way of finding out what all the HDR fuss is about.
Panasonic was so obsessed with nailing high dynamic range picture quality on its flagship 4K TV series for 2016 that it came up with an all-new 'honeycomb' LCD panel technology. This puts physical dividers between the areas of the different 'zones' of picture illuminated by its direct-lit backlight system to cut down on the usual LCD problems of backlight clouding around bright HDR objects, and even introduces a new diffuser filter to try and stop the light 'breaks' between different LED zones looking too obvious.
Even this doesn't completely solve LED's light control issues with very extreme HDR content, but it certainly does enable the TV to deliver picture quality with HDR sources that for the majority of the time are second only to Samsung's KS9500 TVs for their combination of dynamism, detailing and sheer spectacle - and the DX902s cost hundreds of pounds less than their Samsung rivals.
The brilliantly simple attraction of the LG OLEDB6 4K TV range is that they bring you most of the OLED-based picture quality thrills that saw the OLEDE6 range bag a slot right near the top of this list for a much more affordable price.
The thing is, the reasons the OLEDB6 models are so much cheaper than the E6 models are down to things like design, build quality, reduced audio performance and removing 3D playback from the spec list rather than massively compromised image reproduction. So it still delivers the unbeatable black levels, lovely rich colours, extreme contrast and pixel-level light control of its step-up OLEDE6 siblings.
The OLEDE6 doesn't solve OLED's current issue of lost detail in very bright areas of HDR pictures, but it's as good as it gets with the SDR content we still watch for most of the time and remains the natural successor to the plasma TVs so beloved of AV enthusiasts.
On paper the 65PUS7601's pictures shouldn't really work. It only delivers 700 nits of brightness versus the 1000 nits we're seeing from the highest-level TVs this year, and it only hits around 76% of the expanded 'DCI-P3' colour range usually considered necessary for a premium HDR experience.
The reality of watching the 65PUS7601, however, is that once you've wrestled with a rather complicated picture set up system it produces one of the most immersive and spectacular pictures the TV world has to offer. Particularly key to its success is its direct LED backlight system, which manages to deliver a good (albeit not full) sense of HDR without causing nearly as many backlight clouding distractions as any of its more extravagantly bright rivals.
The 65PUS7601 does this, moreover, while also giving you the hundreds of apps available via Google's Android TV smart platform and costing many hundreds of pounds less than other direct-lit 4K rivals like the Panasonic DX902s and Samsung KS9500s.
With the XD9305 series, Sony has joined the other big brands this year in delivering some genuine, HDR-led innovation. In the XD9305's case this takes the form of the Slim Backlight Drive, which cleverly uses two edge-mounted LED light modules and dual light guides to essentially double how locally the XD9305 TVs can control the light in their images.
The result is a contrast performance that gets closer to what you'd normally only see from TVs with a direct LED lighting system at a fraction of the price.
Sony's Triluminos technology also contributes some mesmerisingly good colour handling, while the brand's X1 processing system ensures that both native 4K and upscaled HD sources both looks fantastically detailed and sharp.
Occasional rather defined backlight 'blocking' artefacts and the clunky Android TV smart engine stop the XD9305 TVs from challenging for the top spot on this list, but at their best the XD9305's pictures are genuinely sensational.
The Panasonic DX750s are some of the cheapest TVs around to offer both 4K and HDR playback. Yet despite their affordability they are also very likeable performers. In fact, with the standard dynamic range sources we still spend the vast majority of our time watching they're nothign short of excellent thanks to their winning combination of 4K sharpness, strong contrast and natural, nuanced colour tones.
With HDR the situation is a little less emphatic, as the screen doesn't have the colour or brightness range to provide a truly full blooded HDR performance. There are various occasional backlight distractions with HDR playback too that you have to work hard in the set up menus to try and minimise. Actually, though, for most of the time the DX750s still look good with HDR and deliver at least a flavour of the extra colour and light dynamics that make it so special.
Add to all this Panasonic's friendly, customisable Firefox TV smart engine and you've got a TV range that offers fearsome amounts of bang for your buck.
Oppo A57 Specifications
