LG 55 B4 vs TCL C7K / QM7K 55"-85"

The brightness results in HDR materials LG B4 are very good. It is true that none of them exceed 1000 nits, although the luminance stability is excellent and looks practically the same in every scenario. The only moment where the tested television performs worse is the last scene, although this should not come as a surprise. Large frames filled with a lot of white have always been, and will likely continue to be, somewhat of a weakness for OLED televisions. However, the combination of perfect contrast, black levels, and brightness in the LG B4 allows for a full spectrum of the HDR effect. Additionally, the incredibly high coverage of the DCI-P3 colour gamut, which reached 99%, deserves recognition. As a result, colours look incredibly vibrant and stunning.

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.

The best factory mode prepared by the manufacturer is "Filmmaker," and we used it throughout the entire testing procedure. We must admit that the unit we received straight out of the box had quite decent colour reproduction. The biggest issue in both SDR and HDR content turned out to be white balance. In the former, there was a strong dominance of red, resulting in a noticeable yellow tint in the displayed image, particularly evident on skin tones and whites. In high-quality materials, this colour was also pronounced, but due to a lack of blue, there were also signs of green visible. Besides these shortcomings, we also encountered issues with greyscale and the colours themselves.

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…

LG B4 has been providing very advanced calibration tools in its TVs for years. We can even say that as the only manufacturer on the market, it allows for such deep intervention in image adjustment. Thanks to these, we were able to calibrate the device so well. The evidence of this is the extremely low deltaE errors, which can be said to stand at a reference level. Both SDR and HDR materials now look exactly as the film director intended. It is no coincidence that TVs of this brand are most often used as preview screens for various graphic or post-production studios.

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.

In this paragraph, we will take another look at the tonal transition smoothing feature, but we will also check how the TV handles lower quality material. As we have managed to check, the setting responsible for smooth gradation works quite effectively, although it has its weaker moments. While the feature works well with SDR content, it becomes less useful with HDR content. Even at the lowest of options, it blurs essential details, so we advise against using it.

The image scaling on LG B4 is rated fairly moderately positively. Although there is no edge splitting, the image itself is naturally "soft". We can change this by adjusting the sharpness slider.

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.

The maximum refresh rate we can set on the LG B4 is 120 Hz. This is the absolute minimum for those who require high image smoothness. The manufacturer has implemented a multi-level motion smoother called "TruMotion". It has been divided into two separate sliders that adjust the sharpness of moving images (De-Blur) and stuttering (De-Judder). Both sliders can be set in the range from 0 to 10, with each level affecting the degree of smoothness, so everyone can find their sweet spot.

The LG OLED B4 panel features an average response time of 0.1 ms (which directly results from our measurements), allowing for an incredibly clear image, unattainable for LCD TVs, which have response times of even several milliseconds. This can be clearly seen in images from the "UFO Test", showing no trace of blur trailing behind the object.

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.

The LG B4 television is equipped with four full-fledged HDMI 2.1 ports with a full bandwidth of 48Gbps. All functions corresponding to this standard activated without any issues, and throughout the entire testing procedure, they caused no problems. The combination of such extensive functionality and low input lags leads us to say that the tested television is truly designed for gaming. This is not surprising, considering that the manufacturer has always placed great emphasis on this. Therefore, we can enjoy both a properly implemented HGIG mode and gameplay in Dolby Vision with low latency. Such a tandem will surely attract the attention of all passionate gamers for whom quality is the most important.

A standard feature in televisions from the Korean manufacturer is also the implementation of GameBar, allowing for quick adjustments of settings "on the fly," without the need to exit the game. It also enables image adjustments for individuals with visual impairments, which is an extremely nice touch. Another important piece of information is that when the VRR technology is turned on, we will not experience a drop in contrast. This is, of course, due to the construction of the panel and the lack of conventional backlighting. However, it is normal for shades of grey to flicker slightly, although this is a characteristic feature of this function regardless of the manufacturer and the television.

In summary: The LG B4, like all OLEDs from the manufacturer equipped with 120Hz panels and HDMI 2.1 ports, creates a harmonious whole with the console. In practice, it is a complete television, and if we expect the highest possible efficiency in gaming, the B4 will be the ideal choice.

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.