TCL C6K vs Philips OLED811

TCL C6K is a moderately bright television that can showcase its full capabilities in the best movie conditions – the maximum brightness is around 600 nits. In scenes with large, intense light sources, the HDR effect can be truly satisfying, providing a sense of cinematic sparkle. However, it's important to remember that with local dimming management, there are situations where some elements become dimmed, and sometimes even barely visible. It is clear that there is a lack of proper optimization of the algorithms, although looking at the technical parameters in this price range, the build quality performs very well.

Philips OLED811 uses the new generation WOLED EX panels, also found in models like the LG C6 and Samsung S90H. After calibration we measured about 1500 nits, which is a very good result for an OLED TV. You can see that clearly in films and series. Flashes of light have the right punch, especially when they appear on a dark background. In those scenes the OLED811 can deliver really impressive HDR. Of course this doesn't mean you'll see that level of brightness in every shot. When the screen is filled with a large area of white or a wide explosion, brightness falls to around 600 nits. That's still a good result, but such scenes don't have the same impact as small bright elements on a dark background. That's a known limitation of OLEDs and the OLED811 is no exception.

Colours

Aside from HDR brightness, colours also matter and here Philips also performs very well. It covers almost the entire DCI-P3 gamut, which contains most of the colours used in HDR films and series. So you get rich reds and lush greens, and while watching it's hard to fault it in that regard. It looks a bit worse with the much wider BT.2020 gamut — its most saturated shades are already beyond the reach of this panel. There's also the issue of the white subpixel that the WOLED panel uses to help boost brightness. With very bright colours you can see a certain "washout": the colour is bright but loses some of its intensity. It's in exactly these situations that Samsung Display's QD-OLED panels have the advantage. In most films and series, though, this won't be something that immediately jumps out at you.

This year's TCL televisions have introduced the Filmmaker mode, and it must be said that it is definitely the best choice right out of the box. This is the mode we recommend for everyday viewing of movies and series. Unfortunately, as is often the case, the best does not mean perfect. In the case of SDR content, the image was too warm, as the red was quite prominent in the white balance. On the other hand, with HDR content, we had the opposite impression – the image became cooler than it should have been, due to an excess of blue. There is also the brightness characteristic, which at times led to overexposure. In practice, these issues combined resulted in quite noticeable errors in colour tests, which are hard to accept in a mode advertised as “by the creators”.

The film mode on the Philips OLED811 is sensibly set up straight out of the box. Most colour errors remain minor in both SDR and HDR, so you can comfortably sit down to watch without adjusting the settings first. There are no large inaccuracies that would immediately distract from the film.

It’s not quite perfect, though. The white balance shows a slight lack of red relative to green, so whites and greys can have a faint greenish tint. It’s not a strong colour cast, but measurements clearly show it. There are also small luminance deviations in SDR: some parts of the image are slightly brightened, and the deepest tones aren’t always reproduced evenly. In HDR the TV stays much closer to the reference, although it occasionally lifts detail from the shadows. These are generally things that can be refined. The factory film mode provides a good starting point, and calibration will reveal how much more you can get out of it.

Thanks to the white balance adjustment, we were able to significantly reduce the C6K's tendency to distort colours, which resulted in a very good end result. After calibration, we won't observe the effect of excessive warming of scenes in SDR or overly cooling the image in HDR. However, it is worth taking a closer look at the brightness characteristics. In SDR content, it's hard to have major objections – the picture looks really good, especially in older movies, TV shows, or material from YouTube. It performs significantly worse with HDR content. An analysis of the EOTF curve suggests that everything is fine, but in practice (EOTF in movies), the limitations of the construction become apparent. The television tends to excessively brighten the smallest fragments of the frame, and in other situations, it can overly dim the entire scene. The effect of calibration is therefore noticeable, and regarding colourimetry, the C6K has really gained a lot, but certain limitations resulting from local dimming and actually from its management by the C6K simply cannot be overlooked.

After calibration the Philips OLED811 delivers an image very close to the reference. We managed to even out the white balance and remove the slight colour cast visible in the factory settings. ColorChecker errors for SDR and HDR fell to around 1 to 2, with many samples even below 1. That's a level at which differences from the reference are hard to spot with the naked eye. We also improved the gamma, with only a slight lift remaining in the brightest whites. In HDR the EOTF curve also stays close to the reference, although the TV still tends to slightly boost the brightness of small details, such as stars or subtitles. That gives the picture a bit of extra brightness that shouldn't be there, but otherwise it's hard to find fault. It was already good out of the box, and calibration allowed us to iron out most of the remaining issues.

TCL C6K performs quite well in terms of upscaling. Lower quality materials appear acceptable, and the absence of overscan issues means the image is displayed in full, without cropping. However, one cannot expect miracles – very low quality content won't come to life here, as the image processor has its limitations. On thin lines or details, there is characteristic tearing visible, which indicates a lack of advanced image enhancement algorithms. It is also a shame that the C6K lacks the function of smoothing tonal transitions – in older films or video materials, colour banding can be noticeable and may be distracting during longer viewing sessions.

The OLED811 handles processing lower-quality material reasonably well, though it's far from perfect. The "Banding reduction" function helps smooth tonal transitions and on the low setting gives a pretty good effect. It doesn't remove banding between shades as effectively as similar solutions from some competitors, but at least it doesn't introduce new artefacts. It's a sensible setting for everyday viewing. Still, there's a bit of a letdown, because the MediaTek Pentonic 800 chipset used here can, in other manufacturers' hands, deal with the effects of heavy compression more effectively even at similarly low settings. A lot therefore depends on how a given manufacturer uses its capabilities.

We have a few more comments about the upscaling to 4K. There's plenty of detail, but overall the image looks rather soft. Edges are heavily smoothed, so the picture lacks some sharpness and clarity. You can partially correct this with the sharpness slider in the menu, though that will be extra edge enhancement rather than recovering detail. On the plus side, there's no overscan, and even with an SD signal the TV doesn't crop the edges of the picture.

TCL C6K uses a 144 Hz panel, which is a significant advantage in this price range. It's an important step forward in comparison to the previous model C655 PRO, which only offered 60 Hz in 4K. The difference is especially noticeable when watching sports or playing games – the ball, players, or fast action in the game are displayed more clearly and without losing detail. An interesting fact is the panel's ability to operate at 240 Hz, which the manufacturer doesn't mention in official materials. We will return to this topic when discussing the PC gaming mode.

TCL has also added a feature for movie watchers: "Motion Clarity," which allows users to adjust the image according to their preferences with two simple sliders. You can either keep the visible film frame or opt for a very smooth, almost theatrical effect. This way, everyone can find settings that match their taste.

In terms of motion handling the OLED811 performs superbly. At 120 Hz, which is useful for console gaming and watching sport, the image remains clear and moving objects don't leave noticeable trails. The OLED's fast pixel response helps here. You can see it clearly in the UFO test, even on a dark background. There are also controls for motion smoothing. In movies you can adjust the strength of smoothing to your taste, from preserving a cinematic feel to much smoother motion. A separate blur-reduction control is useful for fast-paced content like live sports broadcasts.

The TCL C6K is a television that can confidently be called equipment designed for gamers. We have 4K at 144 Hz, VRR support, an automatic gaming mode (ALLM), and Dolby Vision Gaming. On top of that, there's a practical Game Bar, which is a panel with the most important settings handy – useful when we want to quickly change something during gameplay (e.g. screen ratio: Yes, you can!). Notably, it has a wide range of VRR, reaching up to 240 Hz. However, this option is mainly for PC gamers who drop below the native 4K resolution. In that case, the television can spread its wings and show additional smoothness, especially in fast e-sport titles. For consoles, we stick with the classic limit of 120 Hz, but the possibilities are still quite broad. The only slight drawback is some minor motion blur that can occasionally be seen in dynamic scenes. Other than that, the C6K offers everything gamers expect from a television.

The OLED811 has almost everything you’d expect from a TV for gaming. It supports 120 Hz at Full HD, 1440p and 4K, and when connected to a PC it can reach up to 165 Hz. It also offers VRR to help avoid screen tearing when frame rates fluctuate, and ALLM, which automatically switches to game mode. So you don’t have to go into the settings every time you start your console.

Another plus is the properly working HGiG, which ensures that once HDR is set on the console the TV doesn’t apply its own changes to image brightness. The Game Bar is also available, letting you check signal parameters and quickly change settings useful while gaming. The list even includes Dolby Vision for games, but there’s a significant catch here, which you’ll read about below.