LG 55 B4 vs TCL C69K / Q6C

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

In terms of brightness, TCL C69K / Q6C is a moderate model. In optimal film conditions, it shows its full potential, achieving a maximum of around 600 nits. In scenes with large, intense light sources, the HDR effect can be truly satisfying, providing a cinematic shimmer. However, it should be noted that when managing backlight zones, there are situations where parts of the image become dimmed, and sometimes they are barely visible. This suggests that there is still a lack of proper optimisation of the algorithms; however, considering the technical parameters in this price range, the design itself still presents very well.

The best factory mode prepared by the manufacturer is "Filmmaker," which is exactly what we used throughout the entire testing procedure. We must admit that the unit we received out of the box had quite good colour reproduction. The biggest problem in both SDR and HDR content turned out to be white balance. In the former, a strong red hue was evident, causing the displayed image to have a pronounced yellow tint, particularly noticeable on skin tones and whites. In higher quality materials, this colour was also accentuated, but due to a lack of blue, there were also signs of green visible. Apart from these issues, we also encountered problems with grayscale and the colours themselves.

The Filmmaker mode, which has made its debut in this year's TCL televisions (including the C69K / Q6C), is definitely the best choice "to start with." This is the mode we recommend for daily film and series viewings. Unfortunately, as is often the case, best does not mean perfect. In SDR material, the image proved to be too warm, with a pronounced red tint in the white balance. We had the opposite impression with HDR content – here the image became cooler than it should, due to an excess of blue. Additionally, there is the characteristic of brightness, which at times resulted in overexposure. In practice, this translated into quite noticeable errors in colour tests, which is difficult to accept in a mode branded as "from the creators."

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

Through white balance correction, we were able to significantly reduce the tendency of C69K / Q6C to distort colours, which yielded a very good final result. After calibration, the issue of excessive warming of scenes in SDR and excessive cooling of the image in HDR disappeared. However, it is worth analysing the brightness characteristics more closely. While in SDR content it is hard to have major objections – the image looks really good, especially in older films, TV programmes or on YouTube – it performs significantly worse in the case of HDR content. Analysis of the EOTF curve suggests that everything is fine, yet in practice (EOTF in films) the limitations of the design itself become apparent. This model has a tendency to excessively brighten small parts of the frame, only to overly dim the entire scene in other situations. The effect of calibration is therefore undeniable, and in terms of colour reproduction, C69K / Q6C gains a lot. Unfortunately, certain limitations arising from local dimming management simply cannot be bypassed.

In this paragraph, we will take another look at the function for smoothing tonal transitions, but we will also check how the television handles lower quality material. As we have managed to verify, the setting responsible for smooth gradation works quite efficiently, although it has its weaker moments. Just as the function works correctly in SDR content, it becomes rather useless in HDR content. Even at the lowest of the options, it blurs essential details, which is why we advise against using it.

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

In terms of image scaling, TCL C69K / Q6C performs quite well. Lower quality content appears acceptable, and thanks to the lack of overscan issues, the image is displayed in full without any cropping. However, one should not expect miracles – very low-quality materials will not gain a second life here, as the image processor has its limitations.

Thin lines and details exhibit characteristic tearing, which reveals the absence of more advanced image enhancement algorithms. It is also a pity that the C69K / Q6C lacks a tone transition smoothing feature. As a result, in older films or video materials, banding of colours can be visible and may become distracting during prolonged viewing.

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

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 televisions, whose response times can be as high as several milliseconds. This is clearly evident in the pictures from the "UFO Test", showing no trail following the object.

The use of a 144 Hz panel in TCL C69K / Q6C is a significant advantage in this price range. It represents an important step forward compared to its predecessor (C655 PRO), which only offered 60 Hz in 4K. The difference is particularly noticeable when watching sports or playing games – the ball, players, or dynamic action in games are displayed more clearly and without loss of detail. Another interesting feature is the panel's ability to work at 240 Hz (which the manufacturer does not officially mention) – we will return to this topic in relation to the PC gaming mode. TCL has also added a feature for movie fans: “Motion Clarity”. This allows users to adjust the picture to their preferences using two simple sliders. We can either keep the visible film frame or opt for very smooth, "

The LG B4 television is equipped with four fully-fledged HDMI 2.1 ports with a full bandwidth of 48Gbps. All features that are identical to this standard were activated without any issues, and throughout the entire testing process, they did not cause any problems. The combination of such extensive functionality and low input lag suggests that the tested television is truly made for gaming. This is not surprising, considering that the manufacturer has always placed great emphasis on this. Therefore, we can enjoy both the properly implemented HGIG mode and gaming in Dolby Vision with low latency. This pairing will certainly attract the attention of all passionate gamers for whom quality is paramount.

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

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

TCL C69K / Q6C is a television that can confidently be described as equipment created with gamers in mind. Here we have 4K at 144 Hz, VRR support, automatic game mode (ALLM), and Dolby Vision Gaming. Additionally, there is a practical Game Bar, which is a panel with the most important settings conveniently at hand – useful when we want to change something quickly during gameplay (e.g. screen aspect ratio: Yes, it can be done!). The wide range of VRR, reaching up to 240 Hz, is particularly noteworthy. However, this option is mainly for PC gamers who will operate below the native 4K resolution. In that case, the television can spread its wings and show additional smoothness, especially in fast-paced e-sports titles. For consoles, we stick to the classic limit of 120 Hz, but even so, the capabilities are truly extensive. The only downside is a slight ghosting that can occasionally be seen in dynamic scenes. Other than that, C69K / Q6C offers everything that gamers expect from a television.