TCL C9K vs Hisense U7S / U77SE

As we mentioned regarding black levels and contrast – the C9K can make a huge impression in synthetic tests. Our measurements showed that on a screen 10% filled with white, the television can achieve... 4000 nits of brightness! It sounds out of this world, but – and here's where the pattern unfortunately repeats – the numbers say one thing, and the practical experience says another. In real movie scenes, the situation looks different. In the best-case scenario, when light effects occupy a large part of the image and the local dimming algorithm doesn't have to ponder too much about what to do with thousands of zones, the effect is really quite good. At that point, the C9K can hit around 1500 nits, which delivers a pleasant, intense burst and can indeed leave a positive impression.

The problem arises with smaller elements – such as stars in the sky, the moon, or individual reflections. That's when the proverbial cat comes out of the bag: the algorithms are not yet refined, and brightness drops to as low as 400–500 nits. That's a huge difference from the potential 4000 nits we saw in lab tests. Why does this happen? Most likely, the television is trying to protect the black levels in this way and minimize the halo effect around bright objects. Unfortunately, this comes at the expense of detail – some details simply vanish, and the scene loses its nature.

The Hisense U7S has considerable HDR potential, but it can’t make full use of it in every scene. On a test pattern it reaches about 1100 nits, so the backlight is genuinely strong. In our brighter film scenes we measured around 640 to 745 nits. That’s still enough for the sun or bright highlights to have a distinct bloom and to show an advantage over SDR material. When the TV needs to light a larger portion of the image, it handles it quite well.

The problem appears with small lights on a dark background. Each of the 192 zones covers an area considerably larger than a tiny point on the screen. If the TV were to drive such a zone strongly, it would brighten the surrounding area along with the light. Hisense tries to avoid that and dims the whole zone. Blacks look better as a result, but a small bright object that should draw the eye also loses intensity. That’s why in two tougher scenes we recorded only 297 and 154 nits. The difference is large: in one shot HDR can impress, and in the next small highlights are noticeably muted. The U7S therefore prioritises keeping deep blacks, even at the expense of bright details. With this number of zones it’s an understandable compromise, but it’s worth remembering that the peak 1100 nits tells us about the backlight’s capability, not how brightly the TV will show every element of a film.

Colours

Hisense markets the U7S as ULED, but that’s a marketing name; the wider colour gamut here is achieved by a PFS phosphor backlight. In our measurements the TV covered about 91% of the DCI-P3 space and 71% of BT.2020. Those are good results, though a little short of the best screens on the market. The biggest shortfall is in green — the TV doesn’t even reach the DCI-P3 boundary there, so the most intense green hues will be less saturated than they should be. Most colours in HDR films and series still look suitably vivid, however. A positive is the repeatability of the results: gamut coverage on test patterns and in film scenes is practically identical.

For colour tests, we once again reached for the Filmmaker mode – a new feature in TCL televisions for 2025. While the direction is a step in the right way, the execution leaves a lot to be desired. The white balance in SDR content turned out to be too warm – there was an excess of red. On the other hand, in HDR, it swung in the opposite direction: the image became excessively blue. The Colour Checker test revealed quite a few colour inaccuracies that were noticeable to the naked eye. An even bigger problem turned out to be what we mentioned above – brightness management. Regardless of whether we were watching SDR or HDR content, the image tended to wash out the entire scene, giving it an unnatural, almost grotesque character. Therefore, it’s hard to call this a "director's mode" – because no director has ever seen such an image.

Factory colours on the Hisense U7S are decent, but there are a few things to fix. In SDR the white balance favours red, so the image looks too warm, in places with a slightly pink tint. You can see this on faces and bright, neutral surfaces. Gamma also runs below the target, so the TV brightens the image, especially in darker areas. That makes it easier to see shadow detail, but the scene loses some of its depth.

In HDR the white balance is a bit more even, but not completely neutral, with midtones lacking blue and the brightest parts lacking red. A bigger problem is the way brightness is reproduced. The EOTF curve shows that a large portion of the midtones is boosted, making the image appear brighter than the source material intends. Color Checker measurements also fare worse than in SDR: many errors are around 3 to 4, and individual ones reach as high as 8. Colours can therefore look attractive, but they're not always faithful to what we should be seeing. There’s room for improvement and we’ll see how much can be corrected with calibration.

After calibration, we finally managed to tame the white balance – and it immediately translated into a more natural image. Colours finally started to look as they should, and the overall presentation was incomparably better than on the factory settings. In other words – it’s worth taking a moment to improve this, as the gain is really significant. The gamma responsible for brightness management also managed to be brought into order in SDR content, and the effect was more than satisfactory. Unfortunately, when we turned on HDR materials, the situation quickly became complicated. No matter how we set the local dimming, the television had a tendency to do what it liked with the image – either it overexposed everything or darkened the darkest parts too much. Just like we saw in the scene from the movie Billy Lynn. Colour-wise, the improvement after calibration makes a great impression, but brightness management in HDR remains the Achilles' heel of the C9K and presents a certain technological limitation.

Calibrating the Hisense U7S did the most for SDR content. We managed to even out the white balance, so the earlier warm tint is gone and whites and greys look neutral. Gamma now sits very close to the reference, so the TV no longer brightens the image unnecessarily and darker scenes have regained depth. Color Checker measurements confirm the improvement: most errors are below 2. For watching regular TV and SDR films, this delivers a really well calibrated picture. Calibration in HDR wasn’t as smooth. The TV lacks an effective way to correct the EOTF curve, so Hisense still interprets the film’s brightness a bit on its own. It brightens parts of the image and, depending on the scene and local dimming, can tone down the brightest elements. That couldn’t be eliminated by calibration. This also shows up in the Color Checker results, where many errors remain around 3–4 and some exceed 7. In SDR the result is therefore very good, but in HDR we have to accept that the TV adds its own interpretation of brightness to the image.

Digital image processing on the TCL C9K is rather average. The smooth tone transition feature seems to be present, but activating it practically changes nothing – colour bands are still visible, and it can unintentionally highlight elements we’d rather keep hidden, such as object textures. Fortunately, it doesn’t remove film grain, but that’s poor consolation given that the effects are still meagre. It’s therefore hard to recommend using this option.

On the other hand, image scaling presents itself much better. Lower quality materials look quite decent – characters and backgrounds are rendered clearly, although of course, with sources like 576p, the laws of physics cannot be fooled. Occasionally, there’s characteristic edge distortion of objects, but that’s the fault of the source itself, not the algorithm. A plus for not having issues with overscan – the image isn't artificially cropped or enlarged.

The processing of lower-quality material in the Hisense U7S is fairly average. The Pentonic 700 chipset used here doesn't cope particularly well with the effects of heavy compression. There's a "Smooth and Gradient Picture" function in the menu, but its performance leaves a lot to be desired. At the low setting it's hard to see any improvement in tonal transitions, though at least the picture doesn't suffer. Medium and high settings still don't remove visible banding between tones and begin to blur details; in our clips parts of characters' faces even vanished. Interestingly, film grain remains untouched at every level. If you do use this function, stick to the low setting. Its current performance needs refinement, but that's mainly down to the processor used here.

Upscaling to 4K performs much better. Lower-resolution content gains clarity, edges are well reproduced and fine details look sharp. That doesn't mean the TV can recover details that weren't in the recording, but it makes good use of what's provided by the source. Another plus is the lack of edge cropping, even with an SD signal.

Similar to the C8K, the C9K is also a really fast TV – both figuratively and literally. It features a 4K panel with a refresh rate of 144 Hz, and at lower resolutions, the panel can even ramp up to 288 Hz. Such speed translates into practice – while watching sports or playing games, the image looks very smooth and clear. Additionally, in movies, we get an extra motion smoother called Motion Clarity, which allows you to adjust the smoothness to your own preferences – from cinematic "judder" to almost theatrical smoothness.

Motion handling on the Hisense U7S is decent thanks to its 144 Hz refresh rate. For films there's also a motion smoothing option with adjustable judder and blur reduction. You can keep a more cinematic feel to motion or increase smoothness if choppy camera pans bother you. High refresh is also useful for sport and gaming, but unfortunately it doesn't solve the panel's biggest problem.

The issue is pixel response time. Fast-moving objects leave long, distinct trails, as our UFO test shows. It's worst on dark backgrounds, where the trail is particularly pronounced. So motion can be smooth, but the moving object loses sharpness, and that difference on the U7S is fairly easy to spot.

From a gaming perspective, the TCL C9K is a complete tool. It features two (out of four) full bandwidth 48 Gbps HDMI 2.1 ports, so all the key technologies work: VRR (Variable Refresh Rate) and ALLM (Auto Low Latency Mode). Additionally, the manufacturer has included a really intuitive Game Bar that allows you to quickly check the most important parameters and adjust settings without fumbling through menus. Also, TCL's policy is a plus – the TV isn’t afraid of any HDR formats, even in game mode. Whether it's HGiG or Dolby Vision for the Xbox Series S/X console – everything works as it should, giving the player plenty of freedom.

The Hisense U7S has plenty to offer gamers. You get two HDMI 2.1 ports and support for 120 Hz in Full HD, 1440p and 4K, so modern consoles’ capabilities are well utilised. When connected to a PC you can use 144 Hz at 4K or switch the resolution to Full HD and run 240 Hz. So there’s a lot of choice, although it’s worth remembering the motion smearing mentioned earlier, which the high refresh rate doesn’t eliminate. VRR and ALLM are present as well. VRR helps keep the picture tear-free when a game’s frame rate changes. ALLM automatically switches the TV into game mode, so you don’t have to go into the menu each time. VRR works from 48 to 240 Hz, with the highest refresh rate available in Full HD. Xbox users can also play in Dolby Vision at 120 Hz. Importantly, that format does not cause significant input lag here. The Game Bar also looks great. It’s clear and attractive, and lets you quickly check what signal the TV is receiving. Handy gaming settings are close to hand too, including shadow brightening. If it’s hard to spot an opponent in a dark game, you can improve visibility without digging through the whole menu.

Our biggest complaint is HGiG. Hisense keeps doing its own tone mapping, which makes setting up HDR on the console confusing. You adjust the checkerboard pattern, and the TV continually alters its appearance. As a result, the point at which the pattern disappears does not correctly indicate the display’s brightness limit, and it’s easy to set the value too high. For this model it’s better to set the target HDR brightness on the console to around 900 to 1000 nits, rather than rely on the configurator.