TCL C655 Pro vs LG OLED C6 (WOLED)

In the HDR effect quality category, the television TCL 655 PRO demonstrates decent capabilities, achieving a peak brightness of 550 nits. This allows for enjoyment of the HDR effects, which is particularly evident in scenes such as the first from the film Life of Pi or the last frame from The Meg. Nevertheless, the limited number of dimming zones causes some issues. While in bright scenes the television performs better than its lower model, in more demanding scenes, such as the second and fourth scenes from Sicario 2, it struggles. The dimming algorithm aims to achieve deep blacks, but at the cost of brightness – resulting in a drop in brightness of even half during those moments. In these more challenging scenes with small elements, it is hard to find any praise, and the HDR effect resembles more of an SDR. Regardless, the colour gamut coverage deserves commendation, which, like in the version without the PRO suffix, is at a very good level.

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.

Each of our television tests is conducted in film mode, which usually offers the best colour reproduction. Nonetheless, even this mode is not free from issues, as we noted in the model TCL 655 PRO.

In the case of HD content, the white balance distinctly shifts towards red, and this effect becomes particularly noticeable in a scene from Star Wars, where the white elements of the scenery take on a pink hue. For 4K HDR material, the situation is better, but there is a noticeable tendency to excessively emphasise the colour blue. As a result, the picture may appear artificially sharp, which proves to be uncomfortable for the eye over a longer period. The brightness characteristics also leave much to be desired. The Gamma graph indicates serious difficulties with excessive brightening, causing the overall presentation to appear washed out. Additionally, the EOTF curve reveals significant problems with reproducing very small elements – they are overly dimmed, as we detailed in the paragraph concerning HDR effects.

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 calibrating the television TCL 655 PRO, a noticeable improvement in white balance is evident, where the tendency for the screen to have an excessive pink hue has been completely eliminated, which was previously visible in the factory mode. The image has taken on more natural tones, especially in white and light elements, positively affecting the overall perception of the picture. Regarding brightness characteristics, the Gamma chart has also improved – the screen is no longer overly bright, which previously made the image appear washed out. However, there are still some issues with the EOTF curve, which are difficult to eliminate due to the design of the television and its limited number of backlight zones. These limitations prevent achieving perfect results in this regard. Nevertheless, despite this minor flaw, the overall effect after calibration is truly outstanding, providing high picture quality and very good colour reproduction.

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 TCL 655 PRO television performs quite well with tonal transitions in lower quality materials. The "Gradual Smoothing" function at a low setting effectively smooths out tonal transitions, but this comes at the expense of losing some important details, such as the texture of objects. One positive aspect is that it does not negatively affect film grain, which helps maintain the natural appearance of the image.

In the context of digital processing, the television adds artificial sharpness. This may appeal to users who prefer a more vivid image. However, those who like a softer, subtler look may find this a drawback. Additionally, a downside is the cropping of the image due to overscan, which limits the field of view and trims the edges of the frame. This can be problematic in certain scenes - for example, news tickers.

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 C655 PRO television is equipped with a 4K panel with a refresh rate of 60 Hz, making it best suited for watching films. Additionally, the "Flicker Reduction" feature allows users to adjust the smoothness of the image, giving them the choice between a smoother motion and a cinematic, frame-by-frame effect. Moreover, the television performs well with lower resolution materials, such as Full HD and 2K, offering a refresh rate of 120 Hz, which will certainly appeal to gamers who can enjoy a smoother picture at the expense of lower resolution.

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 C655 PRO television offers an almost perfect set of features for gamers, supporting all the key technologies that significantly enhance the gaming experience. The ALLM feature automatically switches the television to low latency mode, resulting in improved responsiveness and minimal signal delay – particularly important in dynamic titles. VRR synchronises the screen refresh rate with the number of frames generated by the console, eliminating screen tearing and thus guaranteeing smoother gameplay.

Support for Dolby Vision in gaming mode allows for more detailed colour and contrast reproduction in games that support this format, while the Game Bar provides quick access to essential settings such as response time and latency level. Unfortunately, the model does not support 4K resolution at 120 Hz, which may disappoint the most demanding gamers. However, for those willing to forgo 4K, support for Full HD and 2K at 120 Hz delivers exceptionally smooth visuals, presenting an attractive alternative for enthusiasts of higher refresh rates.

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.