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It's difficult to give the 40DX700 extra marks on value when the whole reason for upgrading from the 40DX600 – the presence of HDR compatibility isn't rendered particularly well.
Is the 40DX700 worth the extra outlay for its superior design? Possibly.
Its matter silver, and remarkably slim, styling does give it the edge over its cheaper stable-mates. However, it's 4K sharpness, effective upscaling from lower-quality sources, and core OS that helps the 40DX700 appear a great all-rounder.
Key here are the 40DX700's user-friendly, fast-working Firefox OS, though just as welcome is its skill with digital files. The latter is extensive: a USB stick hosting all kinds of digital files, from 4K video files in the TS, MP4 and MKV formats to a load of AVI, WMV and other video files all played without a hiccup. Music is handled well, too, with the 40DX700 supporting MP3, M4A, WMA, WAV and FLAC.
Though HDR lacks sparkle, the 40DX700 is a hugely likeable TV. Chief among its appeal is the Firefox OS, which makes everyday use of catch-up TV, apps and general channel hopping, intuitive.
The highlight is the provision of the excellent Freeview Play app, but just as appealing is the chance to customise the menus to add only the features you want. The slim, silver design makes it a worth step-up from the 40DX600, too.
Elsewhere, the 40DX700's 4K detail does impress despite worries over the size of the screen. All levels of video are watchable right down to standard definition, though upscaled Full HD looks especially sharp. A comprehensive and smooth handling of various video and music files is another reason to consider the 40DX700.
What's the point of a HDR TV that isn't built for HDR? While the 40DX700 can technically show HDR material, it doesn't have anywhere near the core brightness required to bring out the extended contrast. There's nothing wrong with the colours the 40DX700 presents for all kinds of highly detailed 4K, Full HD and HD fare, but the 40DX700 does not produce peerless HDR by any stretch. Other weaknesses include some blotchy light patches on the edge LED-lit panel, and a rather tight viewing angle.
Is 40-inches too small to appreciate 4K? Absolutely not, though if you really want to explore and enjoy the new 4K and HDR era to its fullest, the 40DX700 is not the screen for you.
Fact: the 40DX700 does not offer decent HDR. The Ultra HD Premium label – used on only the priciest of TVs being sold in 2016 – should, in my opinion, be called Ultra HD Minimum. Otherwise, folks will buy TVs like the 40DX700 and barely even consider HDR a positive feature, which could kill it off before it's even hit the mass market.
Despite the 40DX700 not having the brightness to properly display HDR's increased contrast, it does produce a fantastically colourful and convincing images across all sources, and its Firefox OS and Freeview Play apps are hard to argue with. Is it a worthy step up from the 40DX600? Indeed, with its sleek design carrying it through despite the HDR confusion.
Jamie is a freelance tech, travel and space journalist based in the UK. He’s been writing regularly for Techradar since it was launched in 2008 and also writes regularly for Forbes, The Telegraph, the South China Morning Post, Sky & Telescope and the Sky At Night magazine as well as other Future titles T3, Digital Camera World, All About Space and Space.com. He also edits two of his own websites, TravGear.com and WhenIsTheNextEclipse.com that reflect his obsession with travel gear and solar eclipse travel. He is the author of A Stargazing Program For Beginners (Springer, 2015),