Sony X90L vs TCL C6KS / C69KS / Q6CS

HDR on the Sony X90L television looks promising. The luminance chart indicated that the TV has a solid power reserve, achieving a maximum of 1000 nits in synthetic tests. But how does this perform in real-world scenarios? In scenes such as the opening of Life of Pi or the final sequence from The Meg, the TV is capable of delivering that power on HDR content, reaching around 800 nits. Unfortunately, displaying small light elements on a black background, like in the scene from Sicario 2, presents greater challenges for the X90L – here the results reach around 600 nits. Nevertheless, when looking at competitive models with mini-LED technology, the effect looks very good and can shine enough to impress us. The colour gamut coverage is also noteworthy, with a result of 96% for DCI-P3 and 76% for BT.2020, which indicates good colour reproduction in HDR content.

And what about HDR? Here the C6KS performs quite well and – as is becoming the theme of this review – just like in the C6K model. The maximum brightness generated by this television is around 600 nits. In bright scenes, this translates to a really solid, cinematic effect and generally, video materials look good here. However, it's important to keep in mind the specifics of the dimming algorithm in this model. When very small, bright points (e.g. stars) appear on a dark background, the television can quite significantly dim them. The goal is simple: to eliminate blooming and maintain the best possible black. It's a reasonable compromise. Most viewers will definitely appreciate deep, “true black” more than additional microscopic details, the display of which could cause the screen to appear greyed out. Such is the nature of local dimming technology in this price range, and one must be aware of this. It’s also worth noting that the TCL C69KS (C6KS) has an additional PFS coating, which is marketed under the QLED technology slogan. Thanks to this, the colours are saturated and vibrant – our measurements showed that the coverage of a wide colour gamut reaches as much as 92%.

The best mode on Sony televisions is the IMAX Enhanced mode. Although IMAX is mainly associated with the cinema experience, the colour reproduction out of the box is average here. In the case of lower quality materials, such as HD – regular television or YouTube – it's worth paying attention to the white balance. It suffers from a shortfall in red and excessive dominance of blue, which gives the image a pinkish hue. The brightness characteristic, or gamma, for HD content is quite acceptable, but a slight boost can cause the image to appear washed out and look as if it’s behind a light fog.

For 4K HDR content, the situation is somewhat different. The white balance shows a significant boost in blue, which makes the image unnaturally sharp and gives it an artificial feel. Such an exaggeration in colour reproduction may not appeal to everyone, especially if one prefers more realistic tones. Additionally, the EOTF curve in Sony X90L looks quite acceptable at first glance. However, at the end of the graph, there are certain fluctuations that suggest the television is trying to maintain the correct brightness to avoid overexposing larger elements.

In contrast to the more expensive C6K model, in the tested C6KS we don't find an option in the menu labelled as Filmmaker Mode. Is this a reason to cry? Absolutely not. Our tests showed that in practice, in terms of colour reproduction, the lack of this specific label makes virtually no difference. The best available Film/Cinema mode here offers an almost identical picture profile to the aforementioned Filmmaker in the more expensive model. So we get a very similar image, just under a different name. Therefore, if you were wondering whether paying extra for the C6K would give you better colours – the answer is: no, in both cases the base is the same and requires slight adjustments.

Sony offers many tools for improving picture quality, including two extra picture modes that we decided to use during testing and apply calibration to. This solution greatly simplifies the calibration process and is very effective, provided you have the right tools. In the case of HD content, white balance was almost perfectly aligned – only one shade of grey exceeds an error value of "1", which is a great result. The same can be said for the brightness characteristic (gamma), which presents almost perfectly, with microscopic deviations of around 0.01.

For 4K HDR content, the situation is not as ideal. Although white balance has been significantly improved, it was not possible to completely eliminate the dominance of blue. Nevertheless, errors in the Colour Checker test only occasionally exceed the value of "2", which means that picture distortions are practically unnoticeable. When it comes to the EOTF curve, it's worth activating the filter in the top right corner "EOTF in Films" – the graph looks correct, but the TV struggles with illuminating very small elements, which is due to the limited number of backlight zones. Despite these minor errors, it's thanks to the calibration that the IMAX Enhanced mode in the Sony X90L makes watching movies feel like a true cinema experience.

Thanks to the white balance adjustment, the C69KS's tendency to distort colours has been effectively limited, leading to a very good final effect. After calibration, we will no longer see excessive warmth in SDR scenes or overly cool tones in HDR. However, it is worth noting the brightness characteristic. In SDR content, there are hardly any objections – the image looks very good, especially in older films, TV shows, or YouTube materials. Evaluating the television's performance in HDR is much more difficult. Analysis of the EOTF curve suggests correct behaviour, but its practical variant shows certain limitations. The C69KS can overly brighten the smallest elements of the frame, while at other times it can dim the entire scene. Calibration has therefore brought clear benefits in terms of colour, but certain limitations resulting from local dimming and the way it is controlled by the C69KS cannot be avoided, which we also observed in the C6K test.

The Sony X90L television features a smooth tonal transition function known as Gentle Gradation, which is incredibly effective. Even at the "low" setting, the effects are satisfactory, but at the "medium" setting, it works like a dream – we recommend using this option for the best results. The image scaling on the Sony X90L is simply excellent. The image is not overly sharpened, which gives a natural effect and makes everything look cohesive. It's clear that the engineers have really put effort into this aspect, creating a solution that impresses and performs well in everyday use. This means that even when watching content like regular television or YouTube, where the image is by nature not stunning, you can enjoy a smooth, coherent, and visually pleasing experience.

The C69KS handles upscaling quite well. The tested 576p content looks surprisingly decent – a considerable amount of detail is preserved, and the algorithm adds a subtle ‘rounding’ effect to sharp edges, making the image appear more cohesive. However, it doesn't perform as well when it comes to smoothing tonal transitions. The television practically cannot improve them, leaving the image in a rather raw state. With older materials, this can be simply exhausting, as the lack of additional processing highlights all imperfections.

Sony X90L with a 120 Hz display is an excellent choice for both gamers and film enthusiasts. The television is equipped with the Motion Flow smoothing feature, which allows for adjusting motion smoothness using two sliders: "smoothness" and "clarity". The "smoothness" slider controls the level of motion fluidity, which affects the reduction of image stuttering, while "clarity" is used to reduce blurriness and enhance motion sharpness, which is especially useful in dynamic scenes.

C69KS offers a simplified motion enhancement panel in movies, allowing users to adjust the intensity of the effect using a slider. This makes it easy to tailor the smoothness to personal preferences. It also deserves credit for the ability to utilise higher refresh rates – even though the panel operates natively in 4K at 60 Hz, by lowering the resolution to 1440p, modes of 120 and 144 Hz can be enabled, on both consoles and PC. This sounds like great news, however, in practice, the image at these settings trails exceptionally badly. The effect is so pronounced that the overall experience simply appears mediocre and loses its appeal in everyday use.

Sony X90L is a TV that performs well in terms of compatibility with consoles and features for gamers. Its 120 Hz panel and two HDMI 2.1 ports with a bandwidth of 48 Gb/s allow for smooth playback of high-resolution games at high frame rates. Gamers can also take advantage of the ALLM feature, which automatically switches the TV to low latency mode, and VRR, which ensures smooth gameplay without frame tearing. The Game Bar is an added bonus – an intuitive tool that provides quick access to essential settings and gaming features, making it easier to control the gameplay.

Unfortunately, when it comes to HDR in games, the Sony X90L has its limitations. It lacks support for HGiG, a standard that many gamers consider crucial for accurate HDR representation in games. While the TV supports Dolby Vision, which theoretically could enhance image quality in games, the practical implementation of this feature is problematic. Dolby Vision in game mode comes with very high input lag, making gameplay less comfortable and precise movements more difficult. Additionally, Dolby Vision cannot be enabled alongside VRR. This means that despite numerous advantages, gamers seeking the perfect HDR in games may feel unsatisfied.

If we overlook the smudging and lack of native 4K at 120 Hz, the C69KS is impressive in how well it performs for gaming. You get everything you would expect from a gaming TV: Variable Refresh Rate (VRR), Auto Low Latency Mode (ALLM), Dolby Vision Gaming mode, and a consistently functioning HGiG. The TV can also operate at 120 or even 144 Hz at lower resolutions, making gameplay on console or PC smoother. Additionally, there's a clear Game Bar that allows you to quickly check key settings while gaming. As a result — despite a few limitations — the C69KS can be a genuinely successful screen for gamers.