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

The HDR brightness performance of the LG B4 is impressive, even though it doesn't surpass 1000 nits. Its luminance stability is consistently strong across various scenarios, delivering a reliable viewing experience. The only instance where the TV shows slight weakness is in scenes with large areas of bright white, which has long been a challenge for OLED technology. However, perfect contrast, deep blacks, and excellent brightness ensure a fully immersive HDR experience. Furthermore, the TV’s remarkable 99% coverage of the DCI-P3 colour gamut enhances its colour vibrancy, making images appear rich and visually striking. This level of colour accuracy and brightness balance firmly places the LG B4 among the top choices for HDR content.

In terms of brightness, the models from 55 to 85 inches in the C7K series are truly impressive. In the best testing conditions, the 65-inch screen achieved over 1200 nits, which practically means that the brightest scenes can dazzle with almost cinematic brilliance. These are not just dry numbers from measurements – during screenings, white skies, explosions, or light reflections on water looked incredibly striking, often giving the impression that the television exceeds its price class. This is particularly effective in scenes with a large area of illumination, where the screen is filled with intense brightness – such as in sun-drenched shots or during dynamic action sequences. Viewers looking for strong HDR will definitely be satisfied.

However, scenes requiring precise control of backlighting – with small points of light on a dark background – are 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 lantern or single reflections, can be less defined or blend in with the surroundings. This is a compromise inherent to MiniLED technology – it provides excellent image depth and blacks at a level that ordinary LCDs do not offer, but this comes at the cost of limited visibility of the smallest lights.

The best factory preset offered by LG B4 is the "Filmmaker" mode, which we used throughout our testing. Straight out of the box, the TV delivered fairly accurate colour reproduction. However, the most significant issue in both SDR and HDR content was the white balance. In SDR, there was a noticeable red dominance, giving the image a distinct yellow tint, particularly evident in skin tones and whites. In HDR, this red hue persisted, but the lack of blue also introduced a greenish tint in certain scenes. Additionally, we observed some inconsistencies in grayscale and colour accuracy. Despite these shortcomings, the overall picture quality was still solid for most viewing scenarios.

The novelty in TCL televisions for 2025 is the long-awaited Filmmaker mode, which until now could be found in most competitive brands. This is great news because this mode is considered the most faithful to 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 this mode does not guarantee perfection. The Filmmaker mode in the TCL C7K is not free from flaws. One could point out the incorrect white balance, particularly the slight dominance of blue, which led to cool, somewhat grayish skin tones. But that was not the biggest problem. The main complaint was excessive brightness exposure, which is clearly visible in the gamma and EOTF charts. The image was simply too bright, at times almost blown out, which affected not only the depth of scenes but also the overall viewing experience. Some details were simply lost, and the whole image looked as if someone had slightly overdone the brightness slider. As always – we decided to see what could be squeezed out of this after calibration. And that’s when things started to get really interesting…

LG B4 has long been known for offering advanced calibration tools, and it remains one of the few manufacturers that allows such in-depth image adjustments. Thanks to these tools, we calibrated the device to an exceptional standard. The result was incredibly low deltaE errors, considered at a reference level. Both SDR and HDR content now display exactly as the filmmaker intended. This level of precision is one of the reasons LG TVs are frequently used as preview monitors in graphic design and 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 tune the white balance, color gamut, and brightness characteristics so precisely that color errors on the ColorChecker palette dropped below a value of 2. For the uninitiated – this is almost a perfect result, which means that the image is very close to what the creators intended. Unfortunately, it looked worse with 4K HDR content. Although we were able to slightly calm the white balance and correct its previous errors, it is still evident that the television has some "MiniLED traits," especially in brightness management. When we checked how the C7K handles the EOTF curve on actual film scenes, and not just on synthetic test patterns, it turned out that the screen still tends to slightly brighten the entire image. This affects the overall experience – black loses some depth, and the image becomes less contrastive 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 color tuning, natural skin tones, and pleasant brightness make movie sessions and everyday content viewing more than satisfactory.

In this section, we will revisit the smooth transition function while also examining how the TV handles lower-quality content. As we’ve found, the setting responsible for smooth gradation is generally effective, though it does have its drawbacks. While the function works well in SDR content, it becomes less useful in HDR content. Even at the lowest setting, it can blur important details, so we advise against using it in such cases.

The image scaling on the LG B4 is assessed moderately positively. While there is no noticeable edge doubling, the image tends to be somewhat "soft." This can be adjusted by tweaking the sharpness slider to improve the clarity.

TCL C7K features a function that, according to the manufacturer, is supposed to smooth out unwanted color 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. Worse still – the function 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 still – it's better to just turn this option off.

When it comes to scaling lower-resolution content, it's already better. SD and HD materials look quite decent, although sometimes we felt 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 was not artificially cropped – everything fit on the screen as it should.

The maximum refresh rate on the LG B4 is 120 Hz, the bare minimum for those requiring high image fluidity. The manufacturer has equipped the TV with a multi-stage motion smoother called "TruMotion." This feature is split into two sliders: one controls the sharpness of moving images (De-Blur) and the other adjusts judder (De-Judder). Both sliders can be set between 0 and 10, with each level affecting the smoothness, so users can easily find their preferred setting.

The LG OLED B4 panel boasts an impressive average response time of 0.1 ms (based on our measurements), delivering an exceptionally clear image that surpasses the capabilities of LCD TVs, which often have response times of several milliseconds. This is particularly noticeable in the "UFO Test" images, where no trailing blur is visible behind moving objects.

The TCL C7K handles motion fluency really well. The panel used in it offers a refresh rate of 144 Hz, which in itself suggests that this TV is something more than just an ordinary "60 Hz" panel. Moreover, if we connect the C7K to a computer and set the resolution to Full HD. But we'll write more about that in the paragraph about gamers and PC collaboration. Back to everyday use – both sports and movies look very good here. Thanks to the fast panel and well-functioning motion smoother, the C7K is great for watching matches, but also for movie screenings. In the menu, we find two sliders – blur reduction and flicker reduction – which allow you to tailor the smoothness effect to your own preferences. At lower settings, we get a more cinematic effect, with a slight stutter in motion. At higher settings – the image becomes more theatrical, smooth to the point of exaggeration. Everyone can set it up according to their liking.

The LG B4 has four full HDMI 2.1 ports, each providing 48Gbps bandwidth. This ensures smooth activation of all relevant features without issues, making the television highly suitable for gaming. With its low input lag and extensive functionality, including well-implemented HGIG mode and Dolby Vision gaming with low latency, the B4 is a strong contender for gamers who demand high quality.

A standout feature is GameBar, which allows for on-the-fly adjustments without interrupting gameplay, as well as image adaptations for those with visual impairments. Another key point is that when VRR technology is enabled, the television maintains its contrast, thanks to the OLED panel's structure, though slight flickering in grey shades is to be expected.

In conclusion, the LG B4 is an ideal choice for gamers, seamlessly combining high performance with excellent gaming features. Its 120Hz panel and HDMI 2.1 ports make it a standout option for those seeking top-tier gaming experiences.

TCL C7K is a television that on paper looks like the dream equipment for gamers – and most importantly, it holds up well in practice. First, the good news: we have two full-bandwidth HDMI 2.1 ports, so we can easily connect both a console and a computer, taking full advantage of 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 suite 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 consistent with the creators' intentions. GameBar, which is an informative bar for the gamer. It operates quickly, looks clear (like the Nintendo console👌), and shows what’s most important: the current frame count, VRR status, and even HDR parameters.