Samsung QN900F vs TCL A400 PRO

QN900F is truly a bright television – it can generate nearly 2000 nits, a figure that remains unattainable for most models available on the market. But the mere ability to achieve such brightness is not everything – it also matters whether the television can make good use of it. And here, it is not always perfect. Our tests on cinematic test patterns showed that in scenes such as those from Life of Pi or The Meg, the QN900F can truly shine – literally and metaphorically. In such moments, its greatest advantage, which is brightness, makes a huge impression. However, in more demanding scenes, challenges arise – similar to when assessing contrast. When smaller, bright elements appear on screen, the television often struggles with the decision: should it highlight them at the expense of black levels, or perhaps maintain deep blacks while toning down brightness. The result is situations where, for example, in the film Sicario 2, brightness dropped to just 200 nits, making details barely visible. Dimming algorithms could definitely be better for a television of this class.

The TCL A400 Pro is a moderately bright TV. Its peak brightness reaches around 600 nits. That level already allows for a real HDR effect, and in many films it does produce a noticeably more attractive picture than in SDR. However, it is not a level that overwhelms with sheer brightness. The A400 Pro therefore isn’t one of those TVs that ‘attack’ the viewer with a powerful flash in every eye-catching scene. The biggest limitation is seen with small bright elements on a dark background. Because of fairly aggressive local dimming control, the TV can significantly reduce their brightness, in extreme cases even to around 100 nits. This means that small lights, sparks, stars or individual highlights can be much less visible than they should be. It’s worth adding, however, that this isn’t without reason. The A400 Pro does this to maintain as deep a black level as possible and to limit the halo effect around bright objects. So it’s an intentional compromise: the TV more often opts for deeper blacks rather than maximally bright, point-like highlights. On one hand this can be understood, especially given the limited number of dimming zones, but on the other you should be aware that the HDR effect won’t always be as strong as the peak brightness alone might suggest.

On the plus side, the colours are a strength. The PFS LED filter used here, marketed by the manufacturer as QLED, allows for suitably saturated colours. Coverage of the DCI-P3 gamut measured around 94%, and BT.2020 around 74%, which is a solid result for this class.

Testing the QN900F in Filmmaker mode, the characteristic features of the image were quickly noticeable, even though this mode is designed to reflect the director’s vision. The white balance was not perfect – the television displayed distinct deficiencies in the blue colour. This made the entire scene take on a warmer tone, as if someone had applied a subtle filter in shades of yellow and orange. In films where bright shots dominate – for example, scenes in the snow or in strong daylight – this gave the impression of slight warmth that did not always convey the director's intent. The second noticeable element was the management of brightness. The QN900F could sometimes brighten the image more than necessary. It looked as though the exposure had been slightly 'pulled up', causing the scene to lose its naturalness. Shadows were sometimes too shallow, and the contrast slightly weakened. These are not disqualifying errors, but for a television in this price range, it is evident that Filmmaker mode has not been perfected one hundred percent. This is particularly noticeable when we compare its image with what was seen after the screen calibration.

As standard, we performed colour measurements in the best‑tuned Filmmaker Mode, the mode that is designed to be closest to the creators' intentions. The A400 Pro of course also offers other picture modes, but in practice these come with considerably larger colour errors and interfere more with the character of the image. Therefore we will not deal with them in detail in this part of the test. So how does the out‑of‑the‑box colour reproduction fare? In short: really very good. Actually, looking at our measurement results, downright excellent. Both the white balance and the luminance response were set surprisingly precisely. The errors were so small that during measurements we genuinely rubbed our eyes in amazement. Such good factory settings do not happen often, even in TVs operating in Filmmaker Mode. All the more credit is due to TCL, because the A400 Pro right out of the box can deliver an image very close to how the source material should look. The results were so good that one could easily think someone had already given this unit extra attention and tried to calibrate it.

Our nitpicking really comes down to just one thing. In SDR content the image was slightly brighter than the dark‑room reference intends, because the factory gamma was set closer to 2.3 than to 2.4. This is not a large error and most viewers will probably not even notice it.

It should, however, be noted that we are talking about our specific test sample. With factory colours there can always be some variation between units, production batches or screen sizes. We do not assume, therefore, that every A400 Pro will look identical straight out of the box.

After calibration, we managed to eliminate errors in white balance and adjust them to a level that can be considered acceptable. It is not perfect, but it is definitely better than the factory settings. Most colour errors now lie within the deltaE 2–3 range, so in practice, they should not be noticeable during everyday viewing. However, the most significant improvement is evident in how the television manages brightness in SDR content. Shadows and details are no longer flattened, which gives the image depth and naturalness. As for 4K HDR material – colours themselves are no longer an issue, but some imperfections of Mini-LED technology can still be observed. The QN900F tends to dim the smallest bright elements too much, causing them to sometimes disappear from view. However, it should be noted that this is a much better solution than boosting the entire screen, which would spoil the contrast. This is more of a characteristic of this technology than a typical flaw, but it is worth keeping in mind. The effects of calibration are truly very good.

Despite its superb factory calibration, we couldn't resist checking how the TCL A400 Pro would respond to professional calibration. Since the starting point was so good, we were all the more curious whether there was anything more to be had from the TV. And here we must boast: we managed to reduce our unit's colour errors to absurdly low levels. Measurements below a value of 1 are not something you see every day, even in very good TVs. Such results are more commonly associated with professional reference monitors than with a lifestyle TV for the living room. In terms of white balance and colour reproduction the A400 Pro therefore simply performed exceptionally well after calibration. The only gripe we have after closer analysis relates to the luminance behaviour. The TV adjusts luminance depending on the content being displayed and quite often the picture is slightly darker than the reference calls for. This is most likely due to the way the Mini-LED backlight and local dimming algorithms operate in this model. However, this does not spoil the overall impression, because in terms of colour accuracy alone the calibrated A400 Pro showed a level that was really hard to expect.

If we want to eliminate jarring tonal transitions that can be irritating, for example, while watching YouTube, we can use a feature called noise reduction. It works really effectively – it removes issues with colour blending when we set it to Standard level. However, as with most Samsung televisions, this does involve some compromises. Although we did not notice this feature significantly affecting the structure of objects in the image, it unfortunately reacts quite aggressively to film grain. Most people will likely appreciate this effect – the noise is simply removed – but if someone is looking for an image as close as possible to reference settings, we definitely recommend turning this option off.

When it comes to scaling, or dealing with very low-quality content, the QN900F performs really well. On the test card with the model, the image appeared clear, with only slight aliasing that shouldn't bother most viewers. However, it is worth mentioning one issue – the television sometimes has problems with so-called overscan, which can cause older content to be slightly cropped. This might manifest, for example, in subtitles disappearing from the bottom of the screen.

Digital image processing is, unfortunately, one of the weaker points of the TCL A400 Pro. That does not mean the TV performs badly, but it is hard to call it anything clearly above average. The upscaling itself is adequate: edges are smoothed fairly well, the picture does not look overly sharp or "pixelated", and lower-quality content can be watched without much discomfort. At the same time, the overall image is slightly soft and lacks the precision offered by the best image processors in more expensive TVs.

Much worse, however, is how it handles tonal transitions caused by strong signal compression. TCL has equipped the A400 Pro with a "Gradual Smoothing" feature that, in theory, should limit visible colour banding and artifacts in lower-quality material. In practice, though, its effectiveness is very limited. It does not improve tonal transitions in any noticeable way, and at higher settings it can also smooth out image details, giving the picture an artificial, slightly blurred character. For that reason, we think it is best to leave this feature off. The A400 Pro copes decently with basic image scaling, but if you often watch heavily compressed content with noticeable posterisation, this model will not be among the best choices.

There really is nothing to complain about here – the QN900F looks very good in terms of motion. With a 165 Hz panel in 4K, it can confidently be said that this television is suitable for both watching sports and gaming. The motion enhancer plays a key role here. It works brilliantly – not only during sports broadcasts, where it can eliminate blurring and image shaking, but also in games, where the animation becomes clearer and smoother. And of course, if someone likes to experiment with films – they also have that option. At lower settings, a slight graininess and cinematic character can be seen, while at higher settings, it takes on a soap opera effect. In other words, everyone can adjust the picture to their preferences, and the television has the power to handle it.

The TCL A400 Pro is equipped with a 144 Hz panel, but in practice we are most interested in its behaviour at 120 Hz. That is the frequency most consoles are limited to today, as well as many sports broadcasts and high-frame-rate content. At that rate the TV performs quite well. The sharpness of moving objects is really good, especially after properly configuring the motion smoothing. The "Motion Clarity" function is responsible for improving smoothness. Its settings include two sliders that let you tailor how the motion smoothing operates to your preferences, separately for lower and higher frame-rate material. This makes it possible to achieve both a more cinematic look and a noticeably smoother picture. Those who do not want to fiddle with manual configuration can use presets such as low, medium, high, cinema or nature.

[UPDATE] We have updated our 2025 Samsung TV reviews following the release of firmware version 1131, which officially restores the essential HGiG (HDR Gaming Interest Group) support.

It really is nice here. The QN900F offers a full set of features that we would expect from a top-end gaming television – we have VRR, ALLM, Game Bar, and also cloud gaming applications. However, the biggest standout is the proprietary motion smoother, which also works in games and – importantly – does not introduce noticeable lag. This is something we won't find with its other competitors. Unfortunately, there is also something concerning. This year, Samsung has evidently messed something up with its televisions. During the testing of the QN900F before its update, it had the HGIG feature, which allowed for perfect adjustment of HDR settings for the console. However, according to our procedures, we always update the equipment to the latest version – in order to give the manufacturer a chance to fix any shortcomings. And here… it turned out the opposite.After the update, the HGIG feature disappeared from the menu, making the correct configuration of the console for HDR practically impossible. It was supposed to be complete – 165Hz, four HDMI 2.1 ports, a full gaming package… but unfortunately, it turned out to be a small blunder. What a shame.

In terms of features for gamers the TCL A400 Pro performs brilliantly. The TV has practically everything you can expect from a gaming TV today: support for 4K at high refresh rates, VRR, ALLM, correct implementation of HDR formats in games including Dolby Vision, and HGiG. That means it works well with both next-generation consoles and a PC. Another plus is the presence of the Game Bar, a special panel with the most important settings for gamers. From it you can quickly check basic information about the signal, refresh rate or active features, and also adjust the appearance and behaviour of some settings to suit your preferences. This solution may not change picture quality by itself, but it greatly improves the convenience of using the TV while gaming.

The only thing to complain about is the number of full HDMI 2.1 ports. The A400 Pro has only two such connectors out of the four available, and one of them also serves as eARC. In practice this means that if someone wants to connect two next-generation consoles and a soundbar, they may run into some limitations. In that scenario you will have to either swap devices or use additional equipment, such as an AV receiver or a soundbar with HDMI inputs. Even so, it is hard not to rate the A400 Pro very highly as a TV for gamers. The gaming feature set here is truly powerful.