LG 55 B4 vs Sony X75WL

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.

The luminosity chart for the X75WL Sony television showed a maximum value of 350 nits, which is unfortunately not an impressive result. The television does not surprise with its brightness, and all the HDR scenes we tested lacked depth and the appropriate light effect that should accompany HDR content. Additionally, the poor coverage of the DCI-P3 colour gamut makes it difficult for the television to reproduce rich colours, which significantly affects the overall viewing experience of HDR content. The lack of adequate brightness and weak colour coverage mean that HDR effects are very limited in this model.

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.

Colour reproduction tests for the model Sony X75WL are carried out in movie mode, which offers the best image settings, but it also has its flaws. The biggest problem with the X75WL Sony is the white balance – for both HD and 4K HDR content – which is characterised by a dominance of blue. As a result, the entire image feels too cold. The colour checker confirms these errors, showing that the colours lean towards cooler tones. In terms of brightness characteristics, the contrast gamma is at a fairly decent level, however, the same cannot be said for the EOTF curve. There are significant issues with maintaining appropriate brightness – the image is either overly bright or too dim, which impacts the visual perception of content.

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.

X75WL Sony is one of those cases where image calibration may not be highly spectacular, but it offers a very good improvement in the perception of colours. The white balance, for both HD and 4K materials, has been significantly improved – there is no longer a strong dominance of cooler shades. The gamma curve also appears more stable, which translates into better image quality. However, the biggest issue remains the EOTF curve, which is responsible for brightness in 4K materials. Due to the technological limitations of the television (IPS panel and lack of local dimming technology), it is hard to speak of a significant improvement, as we cannot extract more from this model. Despite these limitations, the tonal quality of the image has been significantly enhanced.

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 the case of low-quality tonal transitions, the television Sony X75WL performs poorly. The lack of any feature to improve tonal transitions results in noticeable imperfections in colour gradation. However, one can credit the quite good digital processing – the image is displayed without overscan, and overall it looks relatively good thanks to the added slight sharpness, which some users may appreciate.

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 X75WL Sony television is equipped with a 60 Hz panel, making it more suitable for watching films than for dynamic gaming. This model features a motion smoothing function called Motionflow, which allows the user to adjust the picture on a 10-point scale. Smoothness is responsible for adding intermediate frames, thereby increasing the fluidity of motion, while the image becomes more theatrical, minimising the cutting effect. Clarity reduces motion blur, which is particularly useful in fast scenes such as sports or dynamic actions in films. With this feature, users can adjust the fluidity and sharpness of motion to their own preferences.

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.

X75WL is not the best television for gamers. It only has the ALLM (Auto Low Latency Mode) feature and a basic Game Bar, which are not enough to satisfy more demanding users. In this price range, one could expect support for features like VRR or 120 Hz refresh rates - although in FULLHD, which are already standard - unfortunately, they are lacking here. This is a major downside for Sony, as the competition offers much more for gamers in a similar budget.