Our Verdict 
A great start for Panasonic’s 2015 TVs, and a good advert for small 4K screens
For 
Strong 4K performance
Upscales 1080p content well
Bright, punchy colours
Smooth motion
Speedy, user-friendly interface
Against 
Standard-definition picture not great
Freeview Play not available yet
Reviewed on

It’s not just the prices of 4K TVs that have plummeted in recent times, but screen sizes too. Last year, sets below 55in were few and far between, but 40in seems to be the popular starting point in the 2015 TV line-ups.

There’s an argument that a higher resolution on a smaller screen is unnecessary, but it does mean you can watch from a much closer distance. Even nose-to-the-screen close, a 4K TV should look clean and noise-free – provided you're playing well recorded 4K content, of course.

Ideal, then, for smaller living rooms where space might be tight. Or even bedrooms, if you can dare think about having a second 4K screen in the house already.

This 40in Panasonic TX-40CX680B can be yours for just £700 – not much more than a brand-new Full HD model of the same size.

MORE: Panasonic 2015 TVs - everything you need to know

Features

The Panasonic isn't a great fit for standard-definition content. A Full HD set will be a better option

The TX-40CX680B doesn’t have all the bells and whistles of Panasonic’s flagship models, like the 4K Studio Master Processor – the brainpower behind the company’s new colour, contrast and brightness technology.

You have to jump a range higher (to the CX700) for 3D too, and the absence of a smart remote means users have only the vanilla tool that seems to have been part of the Panasonic TV package for years.

Still, there’s plenty for the TX-40CX680B to shout about. It claims to combine new backlight technology and a new colour filter system to produce subtler, more realistic colours. And it also introduces the new (2.0) iteration of Panasonic’s My Home Screen interface, now powered by Firefox.

It’s gone under the knife a bit since last year, ditching the full-page portal and edging nearer LG and Samsung’s line of sight with pop-up menus and colourful graphics. The upshot is a speedier, more user-friendly and customisable interface, and one we like very much.

The home menu is simply a line of bubbles – or ‘decks’ as Panasonic calls them. ‘Live TV’, ‘apps’ and ‘devices’ come as default, but almost anything – whether it’s your favourite TV channel, app or web page, even a media streamer over DLNA – can be pinned to the menu in just two presses of a button.

It’s not quite the fancy affair of LG’s WebOS, but it gets the priorities right by nailing simplicity and convenience – and who can argue with that?

The TX-40CX680B will offer Freeview Play – a rebranded and renovated Freeview – when it launches later this year. For now, Netflix, Amazon Instant Video and YouTube provide hours of 4K material and, of course, endless amounts of regular-resolution programming.

You’ll also find that stacks of apps – Deezer, TuneIn Radio and Eurosport Player among them – can be installed via the app market.

Another new feature is Info Frame, which sparks up navigation bars to access local  weather, recommended content, notifications, and channels so you can scroll through them without disrupting what you’re watching. Briefly holding down the remote’s ‘Home’ button opens it.

Settings are clear and straightforward, and we like how you can scoot through them without having to go back and forth into individual tabs – handy when giving settings the once-over on initial set-up.

There is wi-fi onboard but, as usual, using the LAN socket is the most secure way to get online. It shares space at the back with three HDMI and USB inputs apiece. All HDMI 2.0 inputs are HDCP 2.2 compatible, so ready to play ball with Ultra HD Blu-ray players (and other 4K hardware) when they blow in later this year.

More after the break

Performance

Make sure you fine-tune picture settings to ease its slightly overblown colours

Netflix is one of the best streaming services to satisfy your 4K fix now, so we tuck into comedy Grace and Frankie and are drawn in by the screen’s knifelike edges, astute detail and buttery smooth motion. Each questionable pattern on the cast’s dodgy wardrobe choice is laid bare, and strands of Jane Fonda’s finely combed hair are distinct.

Characters glide across rooms without a blip, but not so much that it looks unnatural. And whether we’re sitting one foot or one metre away, the picture looks squeaky clean.

But tweaking the out-of-the-box brightness and over-keen colouration is a must.  We use a trusty THX Optimizer disc, and find ourselves dialling down the warm and colour settings. Even then, colours are rather on the obvious side. In true Panasonic fashion, they are admirably bright and punchy, if not quite as subtle as we’d like.

Panasonic’s local-dimming technology reduces backlighting behind dark areas of the image to enhance black levels, and pays off a treat. Blacks are gorgeous, so potent indeed, that the black bars almost disappear into the TV’s (ultra thin) bezel. Clean whites don’t let the side down either.

MORE: 5 of the best Panasonic TVs

Dark detail is a little subdued in return – seams in t-shirts and strands in hair get eaten up – which no amount of setting fiddling can improve.

We reluctantly tear ourselves away from 4K to feed the TX-40CX680B Unbroken on Blu-ray. And we don’t feel too hard done by. Switching the ‘24p Smooth Film’ mode to ‘mid’ counters any unwelcome blurring, so when our Olympian war hero takes to the track, both he and the crowd remain stable.

Generally the Panasonic is a good upscaler with high-definition, holding up well next to one our favourite Full HD sets from last year in terms of sharpness and detail.

The same can’t quite be said for standard definition. While the picture isn’t particularly noisy, DVD owners should be prepared for slightly softer lines than they might be used to with a decent conventional Full HD screen.

You can only expect so much from a wafer-thin TV, and the TX-40CX680B can’t perform miracles. The sound through its twin speakers (powered by 10 watts of amplification) is clear and fairly detailed, but a decent bargain basement soundbar or base will grant you more substance and solidity.

You can’t go wrong with Cambridge Audio’s TV5 soundbase (£250). Or even a Yamaha RX-V377 home cinema amp (£250) and Boston Acoustics Soundware XS SE surround package (£220) if room and budget allows.

Verdict

The TX-40CX680B is the first 40in TV we’ve seen this year, and it happens to be very good. Whether it holds its own against yet to be released competition remains to be seen.

Until then, we’re more than happy vouching for the Panasonic. In its own right, it’s a good value set that flies the flag for 4K, offering a fine picture and good stack of features with it. In our minds, that’s £700 well spent.

MORE: 7 of the best 4K TVs for 2015

MORE: Best TVs to buy 2015

Where to buy View all »

Panasonic TX-40CX680B
£475
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