TCL C7K / QM7K 55"-85" vs LG OLED B6

In terms of brightness, the models ranging from 55 to 85 inches in the C7K series are truly impressive. Under optimal testing conditions, the 65-inch screen exceeded 1200 nits, which in practice means that the brightest scenes can dazzle with almost cinematic brilliance. These are not just dry figures from measurements – during screenings, bright skies, explosions, or reflections of light on water looked incredibly striking, often giving the impression that the television exceeds its price range. This is particularly effective in scenes with large areas of illumination, where the screen fills with intense brightness – for instance, in sun-drenched shots or during dynamic action sequences. Viewers looking for strong HDR will definitely be satisfied.

However, scenes that require precise backlight control – with tiny points of light against a dark background – prove to be more challenging. Here, the C7K, despite having over a thousand zones, can still dim brightness to maintain deep blacks. The effect is that in films like Sicario 2 or LIFE of Pi, some details, such as a distant lighthouse or single reflections, may appear less distinct or blend into the surroundings. This is a compromise inherent in MiniLED technology – it provides excellent image depth and blacks at a level not offered by standard LCDs, but this comes at the cost of limited visibility of the tiniest lights.

LG B6 is a moderately bright OLED. After calibration it reaches around 800 nits, roughly 200 nits more than last year's B5. That's down to LG Display's new budget OLED SE panel. In practice this simply provides a bit more headroom and makes HDR look fuller in many scenes than on last year's lower-end OLEDs. That doesn't mean the B6 has no limitations. In very bright shots, when a large part of the screen is brightly lit, brightness can fall below 400 nits. This behaviour is typical of OLED TVs (especially in this segment), and it's then you see the biggest difference compared with pricier models. All the same, we rate the B6's results as really solid. It's still not a TV built to break brightness records, but the HDR effect is strong enough that films really feel like a step up from ordinary SDR picture.

Colour gamut

Using the OLED SE panel has had some impact on wide colour-gamut coverage. Compared with last year's model the figures have dropped by a few percentage points. DCI-P3 reaches about 96%, and BT.2020 around 71%. That doesn't mean the colours on the LG B6 are weak. In most films and TV series they look vivid, well saturated and simply pleasing to the eye. You only notice the difference in very bright, highly colourful scenes. Then colours lose some intensity compared with QD-OLED panels. This is due to the WOLED panel structure. In addition to the red, green and blue subpixels it also uses a white subpixel that helps boost brightness. This comes at a cost: at very high luminance some of the colour is effectively 'diluted' by the white light, so saturation of some hues can be slightly lower. Day-to-day it's not a big problem, but you can see it in the most demanding scenes.

The new feature in TCL TVs for 2025 is the long-awaited Filmmaker mode, which until now has been found in most competing brands. This is great news, as this mode is regarded as the one that best represents the original vision of the creators and is often recommended by enthusiasts of good picture quality. Unfortunately – as is often the case – the mere presence of it does not guarantee perfection. The Filmmaker mode in the TCL C7K is not without its flaws. One could critique the incorrect white balance, particularly the slight dominance of blue, which caused cool, slightly greyish skin tones. But that was not the biggest issue. The main complaint was the excessive brightness exposure, which is clearly visible on the gamma and EOTF graphs. The picture was simply too bright, at times even blown out, which affected not only the richness of the scenes but also the overall viewing experience. Some details were simply lost, and the whole image looked as if someone had overdone the brightness slider a bit. As always – we decided to see what could be squeezed out of this after calibration. And that’s where it started to get really interesting…

We tested the LG B6 in Filmmaker Mode, the best picture setting available straight out of the box. ISF modes give very similar results, but in our tests we always stick to Filmmaker Mode for better comparison with other TVs. Each of them is a far better starting point than Vivid or Eco, where the picture is heavily boosted and noticeably less natural. For SDR content the factory settings perform really well. Colour errors are small, gamma behaves correctly, and the picture looks natural during regular viewing and does not seem overly enhanced.

It's a bit worse with HDR. Once you start playing that kind of content it's quickly apparent the white balance isn't perfectly set. Too much blue and red makes the image take on a slightly pink tint. Colour gamut measurements and the ColorChecker confirm this, with samples clearly shifting in that direction. It's not a defect that completely ruins the picture, but you can notice it with HDR films. So anyone who wants the most faithful image should consider calibration, which we cover later in the review.

After calibration, the TCL C7K put on a really good show, especially when it comes to SDR content. We managed to precisely tune the white balance, colour gamut, and brightness characteristics, resulting in colour errors on the ColorChecker palette dropping below a value of 2. For the uninitiated – this is an almost perfect score, meaning the image is very close to what the creators intended. Unfortunately, things didn’t look as good with 4K HDR content. While we managed to slightly calm down the white balance and correct its previous errors, it still shows that the TV has some "MiniLED traits," especially in brightness management. When we checked how the C7K handles the EOTF curve on actual movie scenes, rather than just synthetic test patterns, it turned out that the screen still has a tendency to slightly brighten the entire image. This affects the overall experience – blacks lose some depth, and the image becomes less contrasty than it should be. Despite these minor shortcomings in HDR content, the overall reception of materials – especially in SDR – is really very good. After calibration, the C7K can display an image that can successfully compete with much more expensive models. Good tuning of colours, natural skin tones, and pleasant brightness make movie sessions and everyday content viewing more than satisfying.

During calibration we focused mainly on HDR material, because that’s where the factory settings needed the most correction. We didn’t neglect SDR, though. After tuning it was brought almost to perfection. Colours are very accurate and brightness is controlled as it should be. The biggest change in HDR came from improving the white balance. After removing excess red and blue the pinkish tint disappeared and the image became much more natural. Skin tones, whites and all colours that had previously leaned towards pink improved. After calibration most errors fell below Delta E 2-3, the threshold at which an average viewer stops noticing differences with the naked eye. So the LG B6 can produce a very accurate picture, especially for the manufacturer’s entry-level OLED model.

TCL C7K comes with a feature that, according to the manufacturer, aims to smooth out unwanted colour transitions – something like a rescue for less successful tonal changes. It's called "Gradual Smoothing" and... well, it sounds ambitious, but in practice, it works very poorly. Regardless of whether we set it to low or high, the difference is minimal. And worse still – the feature can cut out elements from the image that should remain. Fortunately, film grain is left untouched, so at least it doesn't smooth everything indiscriminately, but even so – it's best to just turn this option off.

When it comes to upscaling lower resolution content, it's already better. SD and HD materials look quite decent, although at times we felt that the image loses sharpness and becomes too soft – as if something had taken away its clarity. Fortunately, with very low sources (e.g. 576p), there was no overscan effect, meaning the image wasn't artificially cropped – everything fit on the screen as it should.

LG B6 copes very well with lower-quality material. Much of that is down to effective digital image processing, which can mask some source imperfections without excessively smoothing the whole scene. The "Smooth Gradation" feature proves particularly useful. It lets you noticeably reduce posterization mentioned earlier, especially in dark parts of the image. The safest choice is to set it to Low or Medium. The feature still effectively smooths out harsh tonal transitions, but doesn't yet interfere too much with fine details. Die-hard purists can of course leave it off. Upscaling to 4K also performs very well. Full HD and 720p content retain a fair amount of detail, and the image is neither overly sharpened nor heavily blurred. Some limitations are only noticeable with very poor sources below 720p, where the smallest text and fine elements aren't always perfectly sharp, but this is true for almost every other TV on the market.

TCL C7K handles motion smoothness really well. The panel used in it offers a refresh rate of 144 Hz, which alone suggests that this TV is more than just a regular "60 Hz" panel. Moreover, if we connect the C7K to a computer and set the resolution to Full HD. But we will write more about this in the section for gamers and PC compatibility. Returning to everyday use – both sports and movies look very good here. Thanks to the quick panel and the well-functioning motion smoothening feature, the C7K is great for watching matches as well as for movie screenings. In the menu, we find two sliders – blur reduction and flicker reduction – that allow adjusting the smoothness effect to personal preferences. At lower settings, we get a more cinematic effect, with a slight judder. At higher settings – the image becomes more theatrical, smoothly even to excess. Whatever your taste, everyone can set it to their liking.

One of the biggest advantages of OLED panels is their very fast pixel response time. That keeps the picture sharp and prevents visible smearing that often appears on LCD TVs. It does have a downside, though. During slow camera pans motion can look a bit choppier than on LCD screens, where the slower panel naturally masks some of that effect. Fortunately, on the LG B6 this is easy to tame with TruMotion. With the motion smoothing set correctly you can get smoother motion without giving the picture an exaggerated soap-opera effect.

TCL C7K is a TV that on paper looks like the dream gear for a gamer – and most importantly, it also holds up in practice. First, the good news: we have two HDMI 2.1 ports with full bandwidth, so we can easily connect both a console and a computer, making use of all their capabilities. The panel itself supports a refresh rate of 144 Hz, which gives a considerable advantage in fast-paced games. On top of that, it comes with a full suite of gaming features: VRR (variable refresh rate), ALLM (automatic low latency mode), and Dolby Vision support in games. There’s also an HGiG mode that provides an HDR effect aligned with the creators' intentions. GameBar, which is an information bar for gamers. It operates quickly, looks clear (like a Nintendo console👌), and displays what matters most: the current frame rate, VRR status, and even HDR parameters.

LG OLED B6 has plenty going for gamers; it's a complete base for the PS5, Xbox Series X/S or a solid PC. It comes with four full-size HDMI 2.1 ports with 48 Gb/s bandwidth, so you can forget about annoying cable swapping when you want to connect several newer devices at once. We get a full package of sync technologies, from classic VRR to G-Sync and FreeSync. The panel effortlessly syncs its refresh rate to the frame pacing produced by your console or graphics card. Of course ALLM is present: the B6 automatically recognises when a game is running and immediately cuts latency to a minimum. HDR support is also excellent. The TV supports Dolby Vision, and a correctly implemented HGiG means that after an initial calibration in the console settings the picture won't suffer from blown-out whites or lost detail in bright areas. The icing on the cake is the Game Bar. Instead of digging through the full menu mid-game, a single click lets you correct shadow visibility, tweak chosen parameters or simply check the display's current mode. All of this makes the LG B6 a great choice for gamers.