4K, Ultra HD, 4K Ultra HD – call it what you want – the 'four times HD' TV technology finally arrived in force in 2014, with second-generation 4K TVs, further broadcast trials and even (finally!) some 4K content.
With the next generation of Ultra HD TVs from the likes of LG, Panasonic, Samsung and Sony for 2014 now on sale and making their way through our test rooms for review, it's finally time to seriously consider a 4K set for your next new television.
So, what's it all about? On this page we'll run through the basics of ultra high-definition video, get you up to date on 4K TVs and 4K content, take a look at the 4K Ultra HD TVs on the market – and how the sizes and prices are coming down.
You will also find a round-up all of our 4K TV reviews to date, of which there have been plenty this year. We'll be keeping this page updated as your one-stop for everything Ultra HD, so check back if you're in the market to buy a 4K TV...
MORE: Best 4K TVs to buy 2015
4K TV resolution
Officially 4K resolution is 4096 x 2160 pixels. However, in order to shoe-horn this higher resolution video on to a normal 16:9 picture format for a TV, the resolution has been altered to 3840 x 2160 – still four times the total number of pixels on a Full HD 1080p screen (1920 x 1080).
In order to take full advantage of 4K Ultra HD you will of course need a compatible TV, source and the necessary content packing those all-important extra pixels. And that's where it gets messier: while we're seeing the first 4K TVs going on sale, the issue of content – when we're going to get it, how we're going to play it – is much trickier.
4K content, streaming
There's no denying that 4K Ultra HD is very much a fledgling format. Native content is very hard to come by for consumers anywhere.
Netlfix 4K streaming has finally arrived, with House of Cards: Season 2 making history as the first 4K streaming content from the service, and Breaking Bad in 4K following soon after. Let's hope we see more from Netflix when it comes to UHD streaming.
However, you will need to have a new 4K TV with the HEVC codec that Netflix is using in order to play the content.
Sony and Netflix struck a deal to ensure Sony TVs get the best out of Netflix but we've since seen compatible HEVC TVs from LG, Samsung and Panasonic.
Amazon is also set to join the party, having confirmed its 4K streaming plans earlier this year.
YouTube 4K has also been trialled, using a new codec that cuts the data used by the current streaming option by half.
Other options? If you're in the US, there's the Sony 4K Ultra HD Media Player, which went on sale in July 2013 for $700, and has since been followed by the FMP-X5 media player, which can bring 4K streaming content to 2012 and 2013 TVs.
The FMP-X1 server comes pre-loaded with ten 4K films, has a 2TB hard drive, HDMI and USB connections and connects to your network via an Ethernet connection.
And it sounds like you'll need that wired connection for accessing Sony's 4K download service. Officially called Sony Video Unlimited 4K, the download service is live in the US and promises to be the world's first and only network service to give access to a constantly updated library of 4K films and TV shows.
Philips has also announced its UHD 880 4K media player, a little black box for sending 4K content to Philips TVs.
The downside? There are currently "no plans" for a UK release. We suspect rights issues are the problem, or perhaps Sony is just waiting until the time is right. We shall see.
As for the cost of this 4K content, a single film looks like being $7.99 for a 24-hour rental or $30 to buy. Not cheap, then.
There's also the outside bet that Sony will enable 4K video on the PlayStation 4 with a firmware update, allowing far more people to access Ultra HD video. But don't hold your breath.
After plenty of rumours, it now seems 4K Blu-ray discs will become a reality, with an announcement by the Blu-ray Disc Association pointing to a release by the end of 2015.
Previously, Netflix chief product officer Neil Hunt claimed you'd never get Ultra HD 4K video on disc. Though, yes, he would say that.
"The cost and effort of building a whole new disc format and putting that together for the relatively small number of people who'll have a device in the short term isn't going to happen," according to Hunt.
Reports suggest a triple-layer 100GB optical disc will be the solution to getting a 4K film on disc.
In the meantime, Sony is instead pushing its "Mastered in 4K" Blu-ray discs.
There are now 20 titles in total, including The Amazing Spiderman, Total Recall (2012), Ghostbusters, Battle: Los Angeles, The Karate Kid (2010), Taxi Driver, Angels & Demons, Glory, The Other Guys, Spider-Man (2002), Godzilla, Men in Black, Moneyball, Spider-Man 2 and Pineapple Express.
It's important to remember these aren't "4K Blu-rays" as such, rather movies that have been filmed in 4K, scanned in 4K and then downscaled to 2K (1080p) to fit on a standard Blu-ray.
4K TV prices
This year we've finally seen budget 4K TVs, from both ultra-cheap Chinese manufacturers but also more affordable sets from the big-name brands.
55in and 65in 4K TVs, with prices starting at just over £2000, are now a reality. And that's a far cry from where we were at the start of the year.
And a long way from the first sets: the Sony KD-65X9005A was the first of the almost affordable high-res TVs that we reviewed, but still came in at £6000.
Samsung's 2014 TV range now starts with a 55in at £2300, the U7500 Series, in line with similarly sized and priced models from LG, Toshiba and Panasonic.
Brands such as Seiki will be just as important when it comes to bringing 4K Ultra HD TV to the masses. A 39in Seiki 4K TV recently went on sale for $699 in the US, hot on the tail of a 50in for $1500.
CES 2014 saw budget 4K TVs announced by Kogan and Polaroid, with prices for 50 and 55in sets starting at around $1000, potentially around £600.
4K TV news
CES 2014 saw a whole host of brand new 4K TVs announced from LG, Panasonic, Samsung and Sharp.
The biggest news was that Ultra HDs are now available in 'bendy'. Yep, flexible TVs were perhaps the strangest thing to appear at CES, with both LG and Samsung revealing bendy TVs, showing-off 77in and 105in flexible 4K TVs respectively.
Of course getting all those new products to market, and especially the UK market, is often a different story. Sony has fulfilled that promise, with the 55in and 65in Sony X9 Series TVs now on sale, while the 85in Samsung 4K TV, on sale in the UK, has been joined by 55in and 65in models in Korea.
Talking of OLED TV, it seems with a worryingly low yield for OLED panels – only 1 in 10 is good enough to use – means Samsung seens to be focusing its attention on 4K TV screens for now, instead of OLED. It'll be interesting to see if trend is replicated by other brands.
Apple 4K TV
The Apple iTV has been rumoured longer than many of us can even rememeber (well, a few years at least) and after rumours of a TV with AirPlay and Siri, or even an OLED Apple TV, the latest rumour is of a 4K Ultra HD Apple TV.
We're not sure how much weight to attribute to the analyst behind the rumours but certainly a panel built in cooperation with LG and Samsung sounds believable, and certainly the 55in and 65in sizes are the most common for 4K TVs at the moment.
Certainly 2014 looks like passing without any sign of an Apple iTV...
4K TV broadcasts
What about watching live TV in 4K resolution? Well, like the film content: they're working on it.
The latest 4K trials centred around the 2014 World Cup, with the BBC, Sony and FIFA all working on sending live 4K feeds of selected matches. Sadly, it was hard to actually watch the content live, though Sony did host some events at various retail outlets.
We will wait and see if Sony and FIFA release their 4K World Cup content to a wider audience.
In August 2013, Sky carried out its first ever live 4K trial broadcast using the English Premier League match between West Ham and Stoke City.
The BBC and Sony also trialled 4K Ultra HD broadcasts at the Wimbledon 2013 tennis tournament, with a Sony "4K Experience Zone" showing what the future of live sport on TV could hold. Having worked together on 3D broadcasts, Sony is supplying 4K cameras and engineers in order to test out getting 4K from camera to TV.
The BBC and Sky are also part of the new UHD-Forum, which has been formed to promote 4K TV and is led by the Digital TV Group. The forum's aim is to avoid the confusion that emerged when HD TV and HD-Ready TVs first came on sale. Sky 4K content is also very much on the 'to do' list, with the company stating it has looked at trials.
Meanwhile in Japan, telecoms company NTT West has already trialled streaming 4K TV content over the internet, using new compression technology to send the hi-res pictures to set-top boxes.
4K TV reviews
Interested in splashing the cash? Or perhaps you'll just settle for being interested at this stage... Either way, here are all of our 4K TV reviews (and videos) to date.
They are in chronological order (and dated), and we will of course be keeping this section updated. Click through to read the full reviews on each TV.
More after the break
A £25,000 beast of a TV, the 84 inch Sony 4K TV and it's ten surrounding speakers produce an incredible combination of picture and sound, along with passive 3D technology, and uber smart functions, this 4K Sony undoubtedly wowed us when we had some hands on time with it in our test rooms.
Four stars, tested at £22,500
The LG 4K TV is another giant 84 inch slab of Ultra HD technology – and it should be, at almost £23,000 it costs more than a five year old Porsche Carrera. Thankfully, the good sound, well thought out smart functions, passive 3D functionality, and of course those 4K pictures, did an impressive job of justifying the outlay if you're serious about big-screen 4K.
Read the full LG 84LM960V review
Four stars, tested at £6000
This year we've finally seen a 4K TV at a more affordable price, in a more realistic size, on sale in the UK. Granted, the Sony KD-65X9005 is still expensive, but it's a hefty step in the right direction. And the good news is it looks stunning with 4K content. If only there was more of it. It's not entirely without fault but it's undoubtedly fit for a 4K future.
Read the full Sony KD-65X9005 review
Four stars, tested at £4500
We've finally seen a Philips 4K TV – and we like it. Pictures are excellent with HD and Ultra HD content, there's good upscaling from standard-def and the Ambilight feature is an added bonus.
As often the case with Philips TVs, this set takes while to get set-up right, and the amount of smart TV functionality is a little dissappointing, but regardless this is one of the best 4K TVs we've seen so far, and one of the cheapest on the market in the UK in 2013.
Read the full Philips 65PFL9708 review
Four stars, tested at £5500
This Panasonic 4K TV currently has something of an advantage over rivals: it's the only set that has an HDMI 2.0 connection, which means support for 4K video at 50/60fps, vital for potential future 4K broadcasts.
Thankfully, and more useful for now, is the brilliant picture across the board, no matter what content you throw at it. Realistic colours, good broadcast TV performance and strong UHD images. Another solid 4K Panasonic.
Read the full Panasonic TX-L65WT600 review
Four stars, tested at £5500
LG was one of the first manufacturers to jump on the Ultra HD bandwagon, and after launching with an 84in monsterm, we now have some more realistic LG 4K screen sizes (and prices).
In fact, this set is already available on the market for £1000 cheaper than the price at which we reviewed it. And for 4K and 3D especially, the level of picture performance is impressive.
Read the full LG 65LA970W review
2014 4K TV reviews
Tested at £5500
Toshiba was one of the first companies to get involved in 4K TV and this is the company's latest range (ahead of expected 2014 4K TVs from Tosh').
Unfortunately, it's not quite up to the standard. Not least considering the price. 4K content looks great and colours are nicely judged, while decent 3D performance is a bonus, but blacks lack detail and there are gaps in the spec.
It's a hard one to recommend at this price.
Read the full Toshiba 65L9363 review
Tested at £3600
This Sony 4K TV is superb when it comes to watching 4K content, and if you’re determined to have the latest TV tech, this Sony KD-65X9005B is a good place to start.
Natural colours, excellent speakers and a stylish build are all big positives for this 2014 X Series Sony. But it's not an unequivocal success.
Motion could be smoother and DVD performance is only so-so - upscaling to fill all those pixels on a 65in screen is clearly no easy task. Regardless, it's another solid addition to the UHD market, and relatively good value for a high-tech big-screen.
Read the full Sony KD-65X9005B review
Tested at £3600 - compare prices
Our first five-star 4K TV comes from Samsung. It’s got a whole bunch of sparkling features, including a neat new interface, it looks great, and the picture performance is excellent.
Crucially, not least with the amount of 4K content floating around, the picture performance looks great across 4K, HD and SD resolutions. So you won't have to worry about upscaled DVD and off-air content looking below par.
An impressive start for Samsung's 2014 4K range.
Read the full Samsung UE65HU7500 review
Tested at £2100
Arguably the most eye-catching thing about this 4K TV is the price. Just over £2000 - cheaper if you shop around - for a 55in TV shows we've come a long way when it comes to 4K TV prices.
Luckily, we really like the performane, too. It's not quite the all-rounder that we saw in the Samsung (above), struggling a smidgeon with fast motion, overall sound quality and also when it comes to lower resolution content, but it's still a good option on a relative budget for an Ultra HD television.
A good TV, then, but the competition is increasingly strong, so it's four stars.
Read the full Sony KD-55X8505B review
Tested at £2800 - compare prices
We have mixed feelings about this Panasonic 4K TV. We’re largely very impressed by its picture - but we can’t ignore its lack of support for Netflix 4K in 2014. Thankfully, since our review, it looks like an upgrade is coming.
And when it does, we might reconsider our verdict, because elsewhere this TV reminds us of the Panasonic plasma TVs of old, right down to the warm colour reproduction and ink-deep blacks (even if a little detail is lost at times in those deep black levels).
Upscaling of SD content is good and 3D is fine. If Panasonic can update the spec in line with most 2014 TVs, this would be much easier to recommend.
Read the full Panasonic TX-58AX802B review
Tested at £2300
Timing is everything and this Toshiba Ultra HD TV is a little unfortunate on that front. Strictly speaking this is still one of the company's 2013 models - we're waiting on Tosh's 2014 4K sets.
And the long and the short of it is - this TV is found wanting in pretty much every department againt the best 4K TVs on the market now.
Read the full Toshiba 58L9363DB review
Tested at £2300
This is our first 2014 4K TV from LG and it comes packing a stand-out feature: a new WebOS interface. And it's great. An intuitive system that's easy to use, fast to respond and simple to navigate.
Elsewhere performance is strong. Almost too strong - colours are bold and punchy, and could be more nuanced and subtle at times. The panel could do better when it comes to contrast levels and deep blacks.
Passive 3D performance is pretty good, upscaling SD content is decent and the sound quality of this TV's speakers is better than the average. If you like a punchy colour palette, this is worth a look.
Read the full LG 55UB950V review
Tested at £2300
The 65in model of this Samsung 7500 range was our first five-star 4K TV, so we expected great things from this smaller sibling. And happily, we weren't disappointed. The key to this Samsung's success is top-class picture performance across SD, HD and 4K video.
An easy-to-use, well-endowed smart TV section, sleek design and decent active-shutter 3D pictures make for a fine, five-star television. If you have the space and budget for this set, it's a winner.
Read the full Samsung UE55HU7500 review
Tested at £450
A 4K TV for under £500? Too good to be true? Sadly, yes. OK, so you really do get a 39in TV which can display Ultra HD content but it's a very temperamental experience.
This Bush TV doesn't seem to like 4K content from certain sources or connected via certain inputs, and even when we do get it working, the picture quality is sub-par.
It's a nice headline but this ultra-budget Ultra HD set should be avoided.
Read the full Bush LE-39GBP-A review
Tested at £3800 - Compare prices
There's lots to like about this new LG 4K TV, not least since it can now be found online for under £3000. The webOS interface is slick, 4K pictures look great and there's even decent sound.
The very best 2014 UHD TVs might pip this set for pure performance but this is a solid effort that deserves a place on your 4K TV shortlist.
Read the full LG 65UB980V review
Tested at £1600 - Compare prices
Another five-star Samsung Ultra HD TV. And this one is even more affordable. The ultimate value of 4K is, of course, up to you, the end user – but as to whether 4K resolution is even noticeable at 48in, the answer is a resounding ‘yes’.
If this size is right for you, we certainly recommend taking the plunge on this 7500 Series Samsung.
Read the full Samsung UE48HU7500 review
Tested at £3900
Sony gets in on the five-star 4K act with this far bigger, noticeably more expensive, 65in TV, complete with a curve. Smarter, more stylish and a better performer than the average 4K TV, this is a premium TV with a premium all-round performance.
Read the full Sony KD-65S9005B review
Upcoming 4K TVs
There are plenty more 4K televisions on the horizon, with no doubt a host more not too far away set for launch at CES 2015.
IFA 2014 saw more new product announcements, with the launch of the Toshiba U Series 4K TVs, confirmation of the Panasonic AX900 and flagship X940 Ultra HD televisions and Quantum Dot 4K sets from TCL.
4K TV verdict
Ultra HD 4K TV is now a reality – if you've got the inclination and cash – and that's something to be very excited about.
We've this year found Ultra HD 4K TVs we can really recommend - for SD, HD and 4K content - which makes it all the more pressing that we start seeing more concrete plans for 4K content delivery in the UK.
Thankfully, streaming 4K is here (albeit content is limited), broadcast trials are taking place, and 4K Blu-ray really does look like becoming a reality in 2015.
What's next? Even greater choice of 4K TV sizes and prices would be nice but content is the key component we're looking to see now. Let's see what the rest of 2014 and 2015 brings for 4K...
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