TCL A400 PRO vs LG MRGB85B

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.

LG MRGB85 offers moderate brightness. On test patterns it reaches about 700 nits, which by itself is a decent result. In actual movie scenes the values are lower and most often fall between 400 and 600 nits. Bright, expansive shots perform best. In scenes with a lot of black the TV noticeably limits luminance, trying to maintain the highest possible contrast. The HDR effect is therefore visible, but it is far from the level offered by more advanced Mini-LED designs. Especially in darker parts of films the limitations of edge-lit backlighting and imprecise local dimming become noticeable again.

HDR Colors

A much stronger suit of the MRGB85 is its colors. The TV covers about 95% of the DCI-P3 color space and 74% of BT.2020, allowing HDR material to look vivid and striking. Colors are well saturated, and the difference compared with basic LCD TVs is clearly visible. It is worth noting, however, that this is not a classic RGB backlight, where each of the three primary colors is generated by a separate diode. Red is produced by a PFS phosphor, which expands the palette and yields more saturated red shades. This solution works well for color reproduction, but it does not change the limitations of dimming itself. The LEDs are not driven independently in the way the series name might suggest... so it turns out that Mini RGB is not the same as Mini-LED RGB!

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.

We tested the TV in Filmmaker Mode, because among the available settings it offered the image closest to the reference. However, the out-of-the-box colour reproduction was not perfect. The largest deviations concerned the white balance, with the image showing too much red and not enough blue, which caused the whole picture to shift noticeably towards warmer tones. Whites took on a slightly yellowish tint, and skin tones and bright parts of the image did not always look natural. It was not a fault that completely ruined the viewing experience, but in direct comparison with the same screen after calibration the difference was readily apparent.

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.

Calibration primarily allowed us to correct the white balance and remove the previously noticeable warm tint. After adjustment the whites stopped leaning towards a yellow cast and the colours became more neutral and natural. The biggest improvement was seen in SDR material, where the picture looked even and much closer to reference. A similar effect was achieved in HDR. After calibration the image became more organised, although not all of the TV's limitations could be eliminated. The greatest reservations still concerned intense reds, which were not always reproduced with sufficient precision. In practice the MRGB85 handles everyday SDR content very well, whereas in more demanding HDR material its limitations remain clearly visible.

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.

Upscaling and digital image processing perform quite well on the LG MRGB85. The Alpha 8 AI 4K Gen7 processor efficiently upscales lower-resolution content, and regardless of source you can also easily disable overscan. The TV also copes well with compression artefacts. The "Smooth Gradation" feature can effectively reduce visible banding and tonal unevenness, but it is not always precise. At higher settings it can also smooth out fine details, for example surface textures. On the plus side, it does not remove film grain. It's safest to use the "Low" or "Medium" setting, which gives the best compromise between artefact reduction and preserving detail.

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.

The LG MRGB85 is equipped with a VA panel with a native 144 Hz refresh rate, so it performs very well in terms of motion handling. The TV easily handles 120 Hz content from consoles and higher refresh rates when connected to a PC. That matters not only for gaming but also when watching sport, where camera movement is noticeably smoother than on basic models with 60 Hz panels. We also have TruMotion, which lets you set the level of motion smoothing yourself. You can keep a more cinematic feel to motion or increase smoothness, which works well for sports broadcasts and TV programmes. The adjustment range is wide, so you can easily tailor the smoothing to your own preferences.

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.

When it comes to gaming, the LG MRGB85 performs by far the best. The manufacturer didn't skimp on features and has essentially brought the full suite of functions from pricier TVs to this model. You get three HDMI 2.1 ports with the full 48 Gbit/s bandwidth. Each supports 4K at 120 Hz from a console, and when connected to a PC also 4K at 144 Hz. So you don't need to worry which port to plug your console or PC into, because they all offer the same capabilities. Also on board are VRR, AMD FreeSync Premium, NVIDIA G-Sync Compatible, ALLM and HGiG. There's also Dolby Vision Gaming, which means in supported games you can use high refresh rates and dynamic HDR simultaneously on Xbox. The package is rounded off by Game Optimizer, a handy in-game menu for gamers. Without leaving the game you can change the picture profile, brighten shadow details or check the current frame rate. In terms of gaming features, the MRGB85 therefore offers almost the same as much more expensive LG models.