TCL A400 PRO vs Samsung OLED S95H (S99H) (QD-OLED)

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 deliver a noticeably more appealing picture than in SDR. However, it’s not a level that dazzles by brightness alone. The A400 Pro is not one of those TVs that bombard the viewer with a powerful flash in every dramatic scene. The biggest limitation is visible with small bright elements on a dark background. Because of fairly aggressive zone control, the TV can significantly reduce their brightness, in extreme cases down to around 100 nits. That means small lights, sparks, stars or single highlights can be much less visible than they should be. It should be added, though, that this isn’t done without reason. The A400 Pro does this to keep black levels as deep as possible and to limit the halo effect around bright objects. It’s a deliberate compromise: the TV more often opts for deeper blacks rather than maximising point highlights. On the one hand this is understandable, especially given a 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, delivers suitably saturated colours. Our measurements showed about 94% coverage of the DCI-P3 gamut and around 74% of BT.2020, which is a solid result for this class.

When it comes to pure brightness, the S99H is an astronomically bright TV. Its peak brightness in film scenes can exceed 2,800 nits. Whatever the scene, you can expect powerful HDR effects that are almost blinding, which is exactly what we want from a top‑tier display. By nature, an OLED panel can't maintain that extreme brightness in very bright, full‑screen frames the way it can with small bright highlights, but the results are still excellent. In a bright scene from The Meg the sun still exceeded 2,200 nits. That means the S99H was able to hold a higher brightness than most Mini LED screens on the market. In terms of brightness the S99H is currently the best OLED TV we've tested.

Colour gamut coverage

The S99H also handles colours exceptionally well, thanks directly to the QD‑OLED panel used here. Whether the test used synthetic test patterns or measurements with film material in the background, the results remained very high. The S99H easily covers almost 100% of the DCI‑P3 gamut, and in the most demanding space, BT.2020 it reaches nearly 90%. That's absolute top‑tier performance. These results match what we saw in the new SQD‑Mini‑LED displays, and in real film scenes they even surpass RGB Mini LED displays.

As usual, we carried out colour measurements in the best‑tuned picture mode, Filmmaker Mode, the one intended to be closest to the creators’ intentions. The A400 Pro, of course, also offers other picture modes, but in practice they show much larger colour errors and interfere more with the image character. So we won’t cover them in detail in this part of the review. How does the factory colour reproduction fare? In short: really very well. In fact, looking at our measurements, it’s excellent. Both the white balance and the luminance response were set surprisingly precisely. The errors were so small that during the measurements we genuinely rubbed our eyes in surprise. Such good factory settings don’t happen often, even in televisions running Filmmaker Mode. All the more reason to praise TCL, because the A400 Pro straight out of the box can produce an image very close to how the source material should look. The results were so good you could easily think someone had already given this unit extra attention and tried to calibrate it. Our one bit of nitpicking comes down to a single issue. In SDR material the image was slightly brighter than the reference for a dark room, because the factory gamma was set closer to 2.3 than 2.4. It’s not a large error and most viewers probably won’t even notice it. We should note, however, that we are talking about our specific test unit. There can always be some variation in factory colour between individual units, production batches or screen sizes. We do not assume every A400 Pro will look identical straight out of the box.

Samsung offers a whole host of picture modes and features, but we traditionally recommend choosing FILMMAKER mode, especially if you want the most faithful rendering of the creators' intent. Out of the box the TV is tuned very well, though it has minor flaws. These are mainly a slight deviation in white balance in SDR content and a slightly low gamma. As a result, the picture in a dark room can be a little too bright compared with the reference value of 2.4, which is the standard for watching films with the lights off. These are, of course, small issues, because overall colour reproduction remains very good and the errors in ColorChecker measurements are not large. However, we know that for a screen of the S99H's calibre you can and should expect even more, so we subjected it to professional calibration.

Despite the outstanding factory tuning, we couldn't resist checking how the TCL A400 Pro would respond to professional calibration. With such a strong starting point, we were especially curious whether we could squeeze even more from this TV. And here we have to boast: we managed to bring our sample to absurdly low colour errors. Results below 1 are something you don't see every day, even on very good TVs. Such outcomes are more often 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 after calibration simply excelled. The only thing we can pick on after closer analysis concerns the brightness response. The TV can vary the luminance level depending on the content being displayed, and quite often the picture is a little darker than it should be according to the reference. This most likely stems from the way the Mini-LED backlight and the local dimming algorithms work in this model. That said, it doesn't ruin the overall impression, because in terms of colour precision the A400 Pro after calibration reached a level that was genuinely hard to expect.

After professional calibration, FILMMAKER mode looks practically perfect. Because Samsung offers a rich set of advanced calibration controls, we were able to tune the colours to an almost perfect level. Above all, we managed to even out the white balance and the gamma curve, which resulted in noticeably improved contrast and correct image modelling. In a profile prepared like this there really isn't a single thing to pick apart or call a fault. After calibration, the S99H can deliver an essentially reference-quality picture.

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’s hard to call it anything clearly above standard. The upscaling itself is acceptable: edges are fairly well smoothed, the picture does not look overly sharp or “pixelated”, and lower-quality material can be watched without major discomfort. At the same time the overall image has a slightly soft character and you don’t see the kind of precision that the best image processors in more expensive TVs can offer.

Handling of tonal transitions caused by heavy compression is much worse. TCL equipped the A400 Pro with a “Gradual Smoothing” feature that in theory should reduce visible colour banding and artefacts in lower-quality material. In practice, however, its effectiveness is very limited. It does not improve tonal transitions in any noticeable way, and at higher settings it can further smooth image detail, giving it an artificial, slightly blurred character. For that reason we think it’s best to leave this feature off. The A400 Pro copes decently with basic image scaling, but if you often watch heavily compressed material with visible posterisation, this model will not be one of the best choices.

Upscaling and digital image processing are handled by Samsung's proprietary NQ4 Gen3 processor. It copes very well with scaling lower-resolution content to 4K. The picture is clear without looking artificial or overly sharp. The only fairly specific drawback appears with very old material recorded at 480p or lower. In such cases the TV can slightly crop the edges of the image.

The processor also does a decent job with artefacts visible in low-bitrate material, for example in heavily compressed YouTube videos. The noise reduction function effectively smooths the picture and reduces posterisation, but it works quite aggressively. It can remove not only unwanted artefacts but also some fine detail, and even natural film grain. We, wanting to preserve maximum fidelity to the source material, chose not to use it. However, if someone values a clean, as-smooth-as-possible image more than keeping every detail, it may prove useful.

The TCL A400 Pro is equipped with a 144 Hz panel, but in practice we're most interested in how it performs at 120 Hz. That's the refresh rate most consoles, as well as many sports broadcasts and high-motion sources, are limited to today. In that range the TV performs quite well. Motion clarity is really good, especially after properly configuring the motion smoothing. The 'Motion Clarity' function improves smoothness. Its settings include two sliders that let you tailor the motion smoothing to your preferences, separately for low-frame-rate and high-frame-rate content. This allows you to achieve either a more cinematic look or a noticeably smoother image. If you don't want to fiddle with manual configuration, you can use built-in presets such as Low, Medium, High, Cinema or Nature.

Another major advantage of organic panels is very good motion handling. Thanks to the pixels' near-instant response time, the Samsung S99H shows virtually no smearing. Fast-moving objects don't produce visible halos or trailing artefacts, so the TV performs very well for both sport and gaming. One quirk of OLED screens compared with LCD is the way they render low-frame-rate material. With very slow camera movement the picture can appear noticeably more juddery. This can be quite effectively mitigated using frame interpolation. Samsung lets you adjust judder reduction and motion blur reduction separately, so it's easy to find a compromise between a smoother picture and preserving the cinematic feel of the content.

In terms of gaming features the TCL A400 Pro performs brilliantly. The TV has practically everything you’d 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‑gen consoles and PCs. Another plus is the inclusion of a Game Bar, a dedicated 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 customise the appearance and behaviour of some settings to your preferences. It’s a solution that may not change picture quality by itself, but it greatly improves the convenience of using the TV while gaming. The only thing to criticise is the number of full HDMI 2.1 ports. The A400 Pro has only two such ports out of four, and one of them also serves as eARC. In practice this means that if you want to connect two next‑gen consoles and a soundbar you may run into some limitations. In that scenario you’ll need to either swap devices or use extra equipment, such as an AV receiver or a soundbar with HDMI inputs. Even so, it’s hard not to rate the A400 Pro very highly as a gaming TV. The gaming feature set here is genuinely powerful.

Samsung S99H is also a top TV for gamers. It offers almost every possible and useful feature... well, perhaps except the obvious lack of Dolby Vision for the Xbox console. It’s equipped with four full-fledged HDMI 2.1 ports with the full 48 Gbps bandwidth. That makes it easy to use frame-rate synchronization VRR or automatic low-latency mode (ALLM). This year Samsung also has no issues with proper HGiG support, so HDR setup on a console is quick and free of unnecessary complications. Samsung is also known for interesting extras in its TVs. In the Game Bar menu you’ll find options to add an on-screen crosshair, enlarge the minimap, or change the aspect ratio of the displayed image (PC).

Particularly noteworthy is Samsung’s feature: Game Motion Plus. It’s Samsung’s proprietary motion-smoothing system that uses interpolation to boost smoothness in games. Input lag then rises to around 40 to 50 ms (depending on the strength of the setting), which, compared with the competition, is an excellent result. The system makes gameplay noticeably smoother. So if someone has their eye on a demanding game (e.g. GTA 6 😉) that runs on a console at only 30 fps, the S99H can display it much more smoothly than competing models.