TCL P7K / P79K vs TCL C6KS / C69KS / Q6CS

When it comes to assessing HDR performance, we need to be clear and straightforward without any marketing fluff: the P7K/P79K is not and never was meant to be a champion in this area. The maximum peak brightness that this panel can generate hovers around just 300 nits. This represents a threshold, a sort of thin red line between what can be considered barely satisfactory HDR signal and what is, in reality, only slightly better than standard dynamic range (SDR), unfortunately leaning towards the latter. Synthetic tests confirmed this harsh reality – our measurements taken during movie sessions showed that the luminance in key bright scenes rarely exceeded 200-250 nits. Therefore, this is not a TV that would allow content created in a wide tonal range to truly shine, and that must be openly acknowledged.

Unfortunately, the issue of colour reproduction is presented just as conservatively. Although the manufacturer positions this model within the "QLED" family, owing to the use of a PFS LED filter, the results do not match the heightened expectations. The coverage of the wide DCI-P3 colour gamut reaches only 86%. Compared to the market, this is at best an average result, since most devices that utilise additional layers to expand the colour spectrum easily achieve values at a minimum of 90-92%.

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%.

Every reliable assessment of image quality must start with selecting the most optimal, factory preset mode. In the case of the tested P7K/P79K model, the choice was made without hesitation for the "Film" mode. It is the mode that presents an image closest to the intentions of its creators, avoiding both the exaggerated brightness of the dynamic mode and the excessive dimming known from eco settings. And it must be admitted that, for a device in this price range, the factory calibration is surprisingly decent, although it is not without a few stumbles. The most noticeable shortcoming turned out to be the not entirely correctly set white balance. A slight dominance of the blue component gives the image a subtly cool, frosty character, straying from the ideal neutrality that the director intended to show us. The television handles the reproduction of greyscale in the standard dynamic range much better – the gamma curve is almost exemplary. The only slight reservation can be made for the darkest parts of the image, where a delicate deviation from the norm causes a loss of some detail in the shadows. The most significant challenge, however, for the TCL software was interpreting the HDR signal, as illustrated by the EOTF curve. The television follows its own, rather free path here – the darkest details are disproportionately brightened, followed by a noticeable slowdown in brightness increase for mid-tones. Fortunately, most of these imperfections are of a software nature, which can be eliminated. With that thought in mind, we proceeded to the process of professional calibration.

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.

The calibration process turned out to be spot on, especially in the context of standard dynamic range (SDR) content. We successfully managed to eliminate the tendency of the television to showcase cool tones, restoring white to its natural neutrality. Moreover, the precise adjustment allowed us to correct a slight error in the gamma curve, enabling the darkest parts of the image to regain proper depth, without any signs of unnatural brightness. The results are measurable and impressive – in the ColorChecker test, the vast majority of colour reproduction errors fell below the perceptual threshold, achieving a deltaE value of below 2. This is a result that more expensive models would not be ashamed of. Unfortunately, in the case of HDR content, we encounter a wall in the form of the panel's structural limitations. And although we managed to bring the colours into line, the software's specifics mean that the television still adapts brightness in its own way, as evidenced by the persistent, non-standard EOTF curve. To summarise, calibration adds tremendous value, but it is important to be aware that it won't overcome certain physical barriers. The slightly elevated blacks, resulting from the lack of local dimming, and limited peak brightness mean that HDR content won't always be able to showcase its full potential. This is simply not the main task of this display; its true strength, especially after professional tuning, lies in viewing SDR material.

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.

After a series of harsh evaluations, thankfully, it’s time for some praise, and this is deserved by the TCL AiPQ image processor for its work in the field of digital processing and content scaling. It should be noted right away that we are not talking about the level known from flagship models; nonetheless, in the price segment represented by the P7K/P79K, the results achieved are more than solid. The function that smooths tonal transitions performs particularly well, effectively eliminating posterization, which are the characteristic bands often visible in materials with higher compression, for instance, from choose.tv. The algorithm can elegantly remove unwanted gradients, which ultimately looks really good. The television also handles upscaling competently, which means the task of raising low-resolution materials to 4K standard. The resulting image, although it may seem a bit too sharp out of the box, is fortunately not a problem. The software allows for free adjustment of this parameter using a sharpness slider, allowing the final appearance to be easily tailored to personal preferences.

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.

The issue of fluidity and sharpness of motion image is inextricably linked to the fundamental parameter of the panel, and in the case of the TCL P7K/P79K, we are dealing with a panel that has a native refresh rate of 60 Hz. This specification at the outset defines its capabilities and makes it hard to unequivocally recommend it to enthusiasts of dynamic sports broadcasts. During quick camera movements, the image loses sharpness, and the panel also shows a slight tendency to smudge, which may be noticeable to more sensitive viewers. Fortunately, not everything in this aspect has been left to chance. The manufacturer has implemented a simple motion smoothing system, which is primarily used in film materials recorded at 24 or 30 frames per second. Thanks to a dedicated slider, the user can decide on the final nature of the motion – from maintaining a fully cinematic, slightly jerky image, to achieving a very smooth, almost theatrical effect. It is a simple yet effective tool that allows one to adjust the viewing experience to their own preferences.

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.

Although on paper the native 4K@60Hz matrix might suggest that the TCL P7K/P79K is not a TV tailored for gamers, the reality turns out to be surprisingly different. On the contrary, the manufacturer has ensured a rich set of features that make it a very friendly companion for next-generation consoles. Onboard, we find key technologies such as ALLM, which provides automatic switching to low-latency mode, and VRR, or variable refresh rate, which eliminates screen tearing. The list is rounded off with support for Dolby Vision Gaming and a simple yet functional Game Bar. However, the real and extremely pleasant surprise is something else. It turns out that the TV effortlessly supports a high refresh rate signal of 120Hz, but at lower resolutions – 1080p and 1440p. This is fantastic news for console owners, who know how rarely games run in native 4K at a full 120 frames per second. The option to choose between higher resolution and doubled smoothness is therefore an incredibly sensible compromise.

In summary, while the P7K/P79K may not be the target screen for the most passionate, tournament gamers, it offers a package of options for casual or occasional console users that is hard to find among many competitors at this price point.

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.