TCL C655 / C69B (43" - 50") vs LG OLED C6 (WOLED)

The quality of the HDR effect in the TCL C69B / C655 television is quite average. With a brightness level of 350 nits, although not the worst, it still doesn't allow for a full enjoyment of HDR effects, which require higher luminance to showcase their power. Additionally, despite the application of a quantum dot coating (QLED), the television offers an average coverage of the wide DCI-P3 colour gamut at 91%, which may limit its richness of colours in HDR content.

The HDR performance of the LG C6 is really very good. LG Display's new WOLED panel has primarily brought a considerable increase in brightness. In our unit we measured around 1,500 nits and, importantly, the TV can deliver similar values in many typical film scenes. That gives the HDR the necessary impact. Bright highlights, lamps and sunlight can be really intense, and most HDR films simply look very impressive. Of course it's still an OLED, so brightness falls in scenes with a lot of white. This is well illustrated by the fifth scene in the film The Meg, where the C6 reached around 600 to 700 nits. That's still a very good result, but it also shows that the new panel hasn't shed all the limitations typical of OLEDs.

Colours

When it comes to colours, there is also little to complain about. The C6 covers about 99% of the DCI-P3 gamut and roughly 75% of BT.2020. In practice the colours are very saturated and, importantly, stable across different scenes. This is worth emphasising, because not every TV behaves the same in this respect. In some RGB Mini LED models colour saturation can depend more strongly on image brightness. A wider colour palette is nowadays offered mainly by QD-OLED TVs and new SQD models with a new generation of quantum dots. However, the C6 still performs very strongly here and is able to produce suitably saturated colours in most film scenes.

The television TCL C69B / C655, tested in movie mode, unfortunately does not meet expectations in terms of colour accuracy. Although movie mode suggests better representation, it has almost nothing in common with film. There are many errors evident, particularly in white balance – for both HD and 4K HDR content – where the dominance of the blue colour is very noticeable. For the viewer, this means that the image becomes unnaturally cool, affecting the overall perception of colours and the visual impression. The colour checker confirms these errors, showing that colours shift towards cooler shades.

As for brightness characteristics and the related contrast, gamma is very unstable for the material, which can make the image slightly darker. The EOTF curve for the 4K material shows some errors, with significant deviations towards the end of the graph, which negatively impacts the reception of darker parts of the image.

Right out of the box the LG C6 is pretty well set up, especially if you choose Filmmaker mode. In SDR material the white balance is decent, although as brightness increases it starts to lack a bit of red. The picture becomes a little cooler as a result, but it’s not such a big difference that it stands out during normal viewing. More happens in the brightness response itself. Gamma is a bit low and instead of holding at 2.4 it sits closer to 2.1–2.2 over much of the range. In practice the C6 slightly brightens midtones. Shadows are therefore more readable, but the image loses some depth compared with how it should look in a dark room. In HDR the situation is a bit more interesting. The start of the grayscale looks very good, but from about 20–30% brightness the white balance starts to drift more and more. As brightness rises there’s more red and a noticeable lack of blue. In the brightest highlights the difference is already significant and also affects reproduction of some colors. The EOTF curve itself is handled fairly well over most of the range. The C6 only has a tendency to slightly brighten the image, which we also saw during our film comparisons. The largest deviation appears around the brightest highlights, where the TV begins to adapt the signal to the panel’s capabilities. So the out-of-the-box Filmmaker mode in HDR isn’t perfect, but overall it performs well. The biggest room for improvement is the white balance, especially at high brightness.

After calibration, the movie mode on the TCL C69B / C655 television improves in quality. The greatest improvement can be seen in tonal quality, and the white balance presents itself much better – with no major errors. We will no longer see an excessive dominance of cool tones. Gamma has also been improved, leading to a more stable representation of brightness and contrast. However, due to limitations in the form of the television's average colour palette, Colour Checker tests for 4K materials did not achieve remarkable results. Despite these technological limitations, the image has become more authentic, positively affecting the reception of film content.

LG TVs have been very receptive to calibration for years and the C6 is no exception. After adjustment the white balance was set almost perfectly, and most colour errors dropped to values below 3, often even around 2. In practice this means very accurate colour reproduction, both in SDR and HDR. An interesting quirk only appeared with the luminance response in HDR. On a standard EOTF chart everything looks almost ideal and at first glance it would be hard to criticise. Only when we measured the TV's behaviour with filters based on actual film scenes did it become clear that the C6 has a slight tendency to artificially boost image brightness.

This is not a huge difference and many people may even view it positively, because HDR consequently looks a little more striking. From the perspective of fidelity to the source material this is not ideal, however, as some scenes are simply a touch brighter than the filmmaker intended. Interestingly, this is rather unusual for LG. In previous generations the brand's TVs typically stuck very closely to the reference picture characteristic after calibration. With the C6 we are still very close to the standard, but this subtle brightness boost is indeed noticeable in films and TV series.

The "Gradual Smoothing" function works very well on the TCL C69B television and, surprisingly, does not remove desirable effects such as film grain – unlike some solutions from other manufacturers. When it comes to image scaling, unfortunately, it looks poor. The television artificially sharpens the image, causing the edges of objects to be quite jagged. This state of affairs may appeal to some users who prefer a more "hard" look to the image, but it is not an ideal solution for those who value naturalness and fluidity of details.

Here the LG C6 has taken a real step forward. The TV uses the same processor found in the flagship G6, and in terms of image processing the two models are very similar. That's a considerable plus, because in this area LG's processor this year performs excellently. The "Smooth Gradation" function in particular works very well. With heavily compressed material it can effectively hide ugly banding and artefacts that often appear, for example, in lower-quality streaming. It's best to leave it set to "Low". That way the improvement is clear and the TV does not yet start blurring fine details. Higher settings smooth the image more aggressively but can already remove some of the natural texture of objects on the screen. Upscaling itself also performs very well. Lower-resolution content is sharpened correctly, edges look clean, and the processor quite effectively reconstructs fine details. In this respect the C6 is already very close to LG's best TVs and the differences compared with the G6 are small.

The TCL C69B / C655 television in its smallest variants offers decent, though not perfect, results in terms of motion smoothness. For films, the television features a "Flicker Reduction" function that allows adjustment of motion smoothness on a scale from 1 to 10. With this option, we can tailor the appearance of the image to our cinematic or more theatrical preferences (with either lower or higher speed).

LG C6 received a panel with a maximum refresh rate of 165 Hz, which is great news above all for gamers using a powerful PC. In films, sport or on consoles we will of course make use of up to 120 Hz, but even then it is hard to fault the motion clarity. As befits an OLED, the panel's response time is almost instantaneous. Moving objects therefore do not leave the characteristic smearing or trails that we can still see on LCD televisions. This is especially noticeable in sport and fast-paced games, where the picture remains very clean even during dynamic movement.

For films and television LG has also prepared the TruMotion motion smoothing system. In the user settings you will find two separate sliders. De-Judder primarily addresses low frame-rate content, that is mainly films and TV series at 24 fps. You can use it to slightly reduce the characteristic judder or set a higher value if you want a very smooth image. De-Blur is useful for higher frame-rate material, chiefly sports broadcasts and 50/60 fps television.

The TCL C69B / C655 television in its smallest variants offers a range of features dedicated to gamers, such as ALLM (Auto Low Latency Mode), VRR (Variable Refresh Rate), Dolby Vision for gamers, and Game Bar. ALLM automatically switches the television to low latency mode, improving responsiveness and minimising delays in control. VRR allows the screen refresh rate to synchronise with the number of frames generated by the console, eliminating screen tearing and providing smoother gameplay. Dolby Vision for gamers ensures better colour and contrast reproduction in games that support this format, resulting in enhanced picture quality. Meanwhile, Game Bar provides quick access to game settings and monitors key parameters such as input lag.

However, the television has certain limitations that may affect gaming comfort. The 60 Hz panel does not allow for displaying signals with higher refresh rates, which may impact the smoothness of the image in fast-paced games. The lack of support for G-Sync technology for PCs may also be noticeable when gaming on a computer, especially in demanding, fast-paced titles.

LG has long focused heavily on gamers, and the C6 really lacks nothing important. The TV supports 4K at 120 Hz from consoles, and when connected to a PC it can run at up to 165 Hz. There is also VRR from 40 to 165 Hz, ALLM and a properly working HGiG. A big plus is support for Dolby Vision in games, so the Xbox Series X can use that format without giving up Game Mode. It's rounded off by a Game Bar, from which you can quickly check key signal parameters and change settings without leaving the game. In terms of features, the C6 is therefore one of those TVs that is really hard to fault. Whether you're gaming on a PlayStation, an Xbox or a PC, practically everything you could expect from a modern gaming TV is available here.