IFFALCON U85X vs TCL A400 PRO

iFFALCON U85 handles HDR in a rather twofold manner – on one hand, it can surprise with solid peak brightness of around 650 nits, which places it well above average in this price segment. This is especially evident in bright, full-screen scenes. Examples from films such as Life of Pi or the final test sequences from The Meg prove that the television can maintain the power and essence of HDR effect when the entire panel needs to "ignite," delivering truly satisfying experiences. However, problems arise in high-contrast scenes, where smaller, bright details appear on the screen; the dimming algorithms prioritize black depth to such an extent that they can stifle the brightness of small light points to just 100 nits, which drastically reduces image dynamics and deprives us of the true "bite" we expect from HDR standards. On a brighter note, however, the colours remain impressive, as the use of the PFS phosphor filter (marketed as QLED by the manufacturer) showcases them very well, achieving nearly 94% coverage of the DCI-P3 colour palette, allowing for a vibrant and rich image in most content.

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.

We tested the factory colours on the iFFALCON U85X model in 'Film' mode, which is definitely the most reliable among all available settings, although it is still far from perfect. The main issue that stands out in both SDR and HDR content is the incorrect white balance – an excess of blue and red components gives the image a slight purple tint, which disrupts the naturalness of the film scenes. An even greater challenge is the way the television manages its brightness. Analyzing the gamma chart for the SDR signal, we noticed significant instability: instead of adhering to the standard value of 2.4, the device oscillates around 2.2, only to suddenly make an unnatural jump towards 3.0. In practice, this leads to confusing effects – large, bright areas on the screen appear too dark, while smaller elements are unnecessarily brightened. A similar characteristic can be found in the EOTF curve, which makes the image unpredictable and loses its cinematic authenticity.

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 professional calibration of the movie mode, we must admit that the result is more than satisfactory – the iFFALCON U85X undergoes a true transformation. Colour errors in SDR content have dropped to a level below 2, which makes them virtually imperceptible to the human eye. We have managed to set the white balance almost perfectly, and brightness management (gamma) has become nearly exemplary. As a result, with standard quality materials, the television simply looks perfect and it is difficult to fault it.

In the case of HDR signal, the situation has also significantly improved, although here the nature of the device becomes a bit more evident. Colour errors have been reduced to around 3, which is an outstanding result in this price range. However, it is worth taking a look at the EOTF graph (available on the right side of the screen in the filters: 4K HDR, gamma / EOTF) to notice what is not immediately visible regarding the brightness management by the U85. Although the reference line looks decent, in real film scenes, the television still interprets the signal “in its own way” due to very aggressive local dimming algorithms. Does this disqualify this model for watching HDR content? Absolutely not. It's simply a typical affliction of almost every Mini-LED, which must reconcile high brightness with the attempt to maintain deep blacks. One simply needs to be aware of these technical limitations, which are unavoidable in this segment.

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.

When it comes to upscaling the image to 4K resolution, the iFFALCON U85X performs well. The device efficiently enhances low-quality signals, making even older materials look clean and clear on the 4K panel. At extremely low resolutions, such as 480p, one can notice slightly jagged edges (especially on fine lines), but let's be honest – this is a scenario that you will encounter only when watching very old recordings, so in everyday use, it is not a real problem.

Much worse is the digital processing aimed at smoothing tonal transitions. Although in the menu we find the “Gradual Smoothing” function, its effectiveness is at least questionable. In practice, it does not effectively eliminate banding (colour banding), and worse, it can cause more harm than good. This filter can be too aggressive in areas where it shouldn’t, artificially smoothing details that should not be altered, such as the natural texture of the face or fine details of skin texture. Instead of improving quality, this function can give the image an unnatural, “plastic” appearance, so it is best to use it with great caution or, preferably, leave it switched off.

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.

In contrast to budget constructions, which in dynamic sports scenes can resemble a slideshow, the iFFALCON U85X is a heavyweight contender equipped with a panel that has a native refresh rate of 144Hz. However, it is worth noting that in the world of films, series, or sports, we will primarily operate at 120Hz due to the specifics of how image enhancement systems function. Such a fast panel is excellent news for gamers and sports fans as it opens the door to advanced motion settings that simply do not exist in cheaper 60Hz models.

We manage everything from the menu “Motion Clarity”, where instead of using pre-set, often overly aggressive modes, we definitely recommend our own configuration based on two sliders. The most important of these, motion blur reduction, is responsible for fluidity in films – here, it’s best to aim for a value of around 4, which will maintain a natural, cinematic character of motion without falling into the artificial “soap opera effect.” Meanwhile, the first slider, motion blur reduction, is the key to success in sports broadcasts. In this case, it’s worth going all out and setting it to maximum, ensuring that the image during fast actions on the field remains sharp, while troublesome trailing is eliminated.

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.

iFFALCON U85X is an outstanding piece of equipment for gamers that has just about everything one can expect from a modern screen for consoles or PCs. We find here two full-fledged HDMI 2.1 ports with full bandwidth of 48 Gbps, which opens the door to key technologies such as VRR and ALLM, ensuring smooth gameplay without tearing the image and with minimal latency. The television handles high refresh rates in various resolutions without any problems, and a real curiosity is the mode that allows for achieving up to 240Hz when dropping down to Full HD quality. The whole thing is managed by the Game Bar (which is a faithful copy from TCL), allowing for instant switching of picture modes, customising the interface appearance, or even adding a virtual crosshair in the middle of the screen.

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.