LG 55 B4 vs TCL C7K / QM7K

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.

TCL C7K is one of the brightest MiniLED TVs in its price class. Under optimal testing conditions, the screen can achieve over 1200 nits, resulting in impressive, at times dazzlingly bright scenes. And most importantly – this isn’t just a theory from measurements. In practice, even the brightest moments in movies can shine with true cinematic grandeur. Home HDR cinema fans should be really pleased.

The impression is fantastic, especially in scenes with large areas of brightness – a white sky, explosions, sun reflections, or magical sunsets can surprise with an intensity of light that rarely appears in this price range.

However, things get a bit worse when more challenging scenarios appear on the screen, previously described in terms of contrast – that is, images full of details, with small bright elements on a dark background. In such cases, the C7K often opts to preserve black at the expense of brightness. An example? Scenes from movies like Sicario 2 or Life of Pi, where small light sources (like a distant lantern) may become less visible, and details in the lights are simply dimmed or blend into the background.

For many viewers, this may be an acceptable compromise – as we achieve deep blacks and pleasant image depth. Nevertheless, it’s important to recognise that the visibility of small details in bright areas is not this model's strong suit. It’s simply a technological limitation that still exists – even with over 300 zones.

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.

A new feature in TCL televisions 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 considered the most faithful to the original vision of the creators and is often recommended by enthusiasts of quality visuals. 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 faults. There are issues with inaccurate white balance, particularly a slight blue tint that resulted in cool, somewhat greyish skin tones. But that wasn’t the biggest problem. The main complaint was excessive brightness exposure, which is clearly visible on gamma and EOTF charts. The image was simply too bright, at times even blown out, which affected not only the texture of scenes but also the overall viewing experience. Some details were just lost, and the entire image looked as if someone had overdone the brightness slider. As always, we decided to see what could be squeezed out of it after calibration. And this is where things 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 showed itself in a really good light, especially when it comes to SDR content. We managed to precisely tune the white balance, colour gamut, and brightness characteristics so that the colour errors on the ColorChecker palette fell below a value of 2. For the uninitiated – this is nearly a perfect result, which means that the image is very close to what the creators intended. Unfortunately, it was a different story with 4K HDR content. While we were able to slightly calm down the white balance and correct its earlier errors, it was still evident that the TV has some "MiniLED traits", particularly in brightness management. When we checked how the C7K handled the EOTF curve on real film scenes, rather than just on synthetic test patterns, it turned out that the screen still had a tendency to slightly brighten the entire image. This affects the overall experience – the black loses some depth, and the image becomes less contrasty than it should be. Despite these minor issues with 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 colour tuning, natural skin tones, and pleasant brightness make movie watching and everyday content viewing more than satisfactory.

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 has a feature that, according to the manufacturer, is meant to smooth out undesirable colour transitions – something like a rescue for less successful tonal shifts. 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. Worse still – the feature can cut out elements from the image that should remain. Fortunately, film grain remains untouched, so at least it doesn't smooth everything indiscriminately, but even so – it's better to simply 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 had the impression that the image loses sharpness and becomes too soft – as if something took 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 fluidity really well. The panel it uses offers a refresh rate of 144 Hz, which suggests that this TV is more than just a standard "60 Hz" panel. Furthermore, if we connect the C7K to a computer and set the resolution to Full HD. But we will write more about this in the paragraph on gamers and PC compatibility. Returning to everyday use – both sports and movies look very good here. Thanks to the fast panel and the well-functioning motion smoother, the C7K is great for watching matches, but also for movie screenings. In the menu, we find two sliders – motion blur reduction and flicker reduction – that allow you to adjust the fluidity effect to your own preferences. At lower settings, we get a more cinematic effect, with slight judder. At higher settings – the image becomes more theatrical, fluid to the point of excess. Whatever your preference – everyone can set it their own way.

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 television that on paper looks like the perfect equipment for gamers – and most importantly, it performs well in practice too. Here's some good news: we have two full-bandwidth HDMI 2.1 ports, so we can easily connect both a console and a computer, using all their capabilities. The panel itself supports a refresh rate of 144 Hz, which provides a significant advantage in dynamic games. Additionally, it comes with a full set of gaming features: VRR (variable refresh rate), ALLM (automatic low latency mode), and support for Dolby Vision in games. There's also an HGiG mode that allows for HDR effects that align with the creators' intentions. GameBar, which is an information bar for gamers. It operates quickly, looks clear (like a Nintendo console👌), and shows what's most important: the current frame rate, VRR status, and even HDR parameters.