TCL 55DP648 4K HDR TV review

While TCL is a global giant when it comes to panel manufacture and its TVs are well-regarded in other markets, particularly the US, it has been slow to 
make an entry to the UK, only arriving in Summer 2018. The 55DP648 reviewed here is part of its first wave 
of sets – a 55in 4K model with a price tag of just £500. Can it do enough to help the Chinese brand get off to a flying start?

Some of its features suggest it might. For instance, 
it uses a VA-type panel, rather than an IPS one often 
seen on low-cost flatscreens. VA panels generally deliver significantly better contrast than IPS rivals – although 
the latter provide a wider effective viewing angle. TCL 
also claims the TV's colour handling reaches 95% of the DCI-P3 colour space. Its native 4K pixel count is also joined by HDR support, in both HDR10 and HLG flavours, and the set offers Freeview Play integration (providing access to all of the UK’s main terrestrial broadcasting catch-up services), 
as well as Netflix in both 4K and HDR, and YouTube.

Yet there are also some things that those with knowledge of TCL's US models might be looking for 
that are missing. One concerns its panel illumination. The 55DP648 uses edge LED lighting rather than a direct LED array, and there’s no local dimming; the TV can only dim all of its LEDs uniformly based on an ongoing analysis of the picture it’s showing. This approach seems likely to struggle to deliver contrast as good as those of TCL’s predominantly direct-lit American models (which also add Dolby Vision HDR to the feature roster).

And there’s more disappointment when you start exploring the 55DP648’s smart menus. These look basic and somewhat out-dated, with no trace of either the 
Roku platform TCL uses in the US, or the Android system 
it employs elsewhere in Europe (although to be honest, 
not having Android is no great loss…). Amazon Prime 
Video was AWOL at the time of writing, too, as was Rakuten TV and Now TV.

If you want this TCL to be a streaming TV partner, you might want to add a third-party media player.

A cut above
For an affordable largescreen TV, the 55DP648 
is attractive. Its bodywork is startlingly thin, both 
at the back and around the screen. Its gleaming metallic finish is also a cut above the budget norm. In fact, the only real exterior hint at the 55DP648’s budget nature is its provision of just two USB ports and three HDMI inputs, when most 4K TVs these days muster three and four respectively.

There’s an odd quirk with these HDMIs, too, 
in that you need to activate an HDMI 2.0 feature 
in a distant sub-menu of the Systems menu 
before HDR plays into the TV properly.

The 55DP648 provides precious few picture settings to play with. Just remember that Movie mode gives the brightest HDR picture, while the Natural preset sacrifices a little brightness to provide a less intense colour palette.

The Dynamic setting you’d normally expect to deliver the most punchy picture takes the average brightness level of HDR content too low, as it tries to provide the appearance of a wider light range between the darkest and lightest parts of the image. And this facet 
of the Dynamic mode gives an early 
warning as to the 55DP648’s biggest picture quality limitation: its lack 
of brightness. In fact, at best it only measured 297 nits when showing a 
10 per cent white HDR window, which is only marginally above the sort of light level needed to show SDR material. Hardly surprising, then, that the set doesn't do much justice to high dynamic range movies. There’s only a marginal increase in even the brightness of small light peaks when you switch between SDR and HDR sources, and even less increase in average brightness levels. In fact, the need to offer an expanded light range when you’ve got such limited peak brightness 
to play with can result in HDR pictures often looking less bright than SDR counterparts.


Fallen brightness
The bright exteriors on Isla Nublar in Jurassic World: 
Fallen Kingdom on 4K Blu-ray highlight this problem well, sometimes looking less intense overall on the 55DP648 than they do if you watch the SDR Blu-ray.

The tough demands HDR places on a TVs’ light controls also expose black level issues. The night-time shots at the start of ...Fallen Kingdom appear here slightly grey, rather than inky black as they should. This is especially noticeable when the darkness has to share the screen with something bright, such as the film’s glowing title, or artificial lighting.

This opening scene also finds corners of the picture unnaturally brighter than the rest of the image, as the 
TCL's edge LED system fails to distribute its light evenly.

There are dynamic contrast and backlight adjustments in the 55DP648’s menus that can reduce the greyness. But these adjust the backlight slowly and heavy-handedly, and prove distracting.

These average black levels and brightness inevitably restrict the sort of colour volume (brightness applied to colour) the 55DP648 
can produce, despite its wide colour panel design. 
The expanded colour spectrums are part of the attraction of most HDR sources, and in this regard 
the TV fails to dazzle.

It also loses brightness and colour if viewed from an angle of more than 25 degrees – a problem that, admittedly, doesn't just affect entry-level LCD 
models. And its lack of light control and contrast prevents it from delivering fine detail in the ...Fallen Kingdom 4K Blu-ray picture as successfully as more expensive TVs.

Back to Blu-ray
Okay, so the 55DP648 hasn’t exactly blown me 
away so far. Fortunately, though, it becomes much more interesting if you think of it as just a budget standard dynamic range 4K TV, suited to your Blu-ray collection and broadcast sources.

Switching to the Full HD (and SDR) Blu-ray of ...Fallen Kingdom, the set's black levels immediately look much more consistently convincing, actually outperforming many budget rivals. Colours are reasonably rich and balanced, and 
the picture no longer feels uncomfortably dark, even 
if it certainly never looks particularly bright. Colour blends 
and skin tones are free of banding and blocking noise, 
and the overall viewing experience is agreeable – consider the size of the TV and the meagre asking price, and the appeal grows even more.

And the 55DP648 also upscales the HD images of 
the ...Fallen Kingdom Blu-ray pretty well. There’s a clear increase in detail and sharpness, without TCL's upscaling processing exaggerating source noise.

Another palpable mark in the plus column comes from the TV's input lag, which I measured at just 10ms when 
the Game mode was selected. This humbles pretty much any other TV available, including premium models, and makes for a responsive gaming session – although, of course, while its image lag might be imperceptible, game graphics miss the visual impact provided by other brighter, crisper displays.

While the TV's skinny design is attractive, it doesn’t leave much room for a potent integrated sound system; TCL's 2 x 8W speaker rig is somewhat feeble. Bass is underpowered, and the sound feels congested and muted. Dinosaur feet pounding the earth in ...Fallen Kingdom aren't conveyed with scale or terror, and there’s no force behind supposedly punchy sounds like gunshots and explosions. Dialogue is reasonably clear and believable, at least 
– but with streamed sources I had noticeable lip-sync issues that made them all but unwatchable. The set does provide an audio delay system, but this wasn't able 
to fix the problem.

The final judgement, then, is the 55DP648 performs well in some areas, but falls short in others. Its 
major selling point is its price/size ratio, rather than 
its smart TV system or 4K HDR performance, and other brands are muscling in on this area too; you can pick up Philips’ superior (in every way) 55PUS6753 for £130 more than the 55DP648, for instance. That said, if you can’t stretch past £500 and you’re after a 55in set for 4K (predominantly SDR) viewing, this does the job fine.

HCC Verdict

TCL 55DP648

Price: £500

We say: While this 55-incher isn't bright enough for immersive HDR playback and deploys a very basic smart system, it’s still a solid SDR 4K option for its money.

Performance: 3/5
Design: 4/5
Features: 3/5
Overall: 3/5


3D: No
4K: Yes. 3,840 x 2,160
Tuner: Yes. Freeview HD; satellite
Connections: 3 x HDMI inputs; 2 x USB ports; RF input; headphone jack; optical digital audio output; Ethernet
Sound (claimed): 2 x 8W
Brightness (claimed): 310 nits
Contrast ratio (claimed): 'Mega'
Dimensions (off stand): 1,227(w) x 715(h) x 75(d)mm
Weight (off stand): 14.8kg
Features: Built-in Wi-Fi; USB/DLNA multimedia playback; 10-bit panel; edge LED system with micro dimming processing; Freeview Play for UK catch-up TV services; TCL smart system includes Netflix 4K HDR; UHD colour extender processing; 5mm-thin bezel