TCL P755 vs TCL A400 PRO

TCL P755 provides average HDR effect quality. The maximum brightness of the TV is slightly below 300 nits. Such brightness limits the intensity of bright areas in HDR content. In practice, this means that bright elements may not be sufficiently pronounced, affecting the overall impression of contrast. However, the TV offers wide coverage of the DCI P3 colour gamut, reaching about 93%. As a result, colours are vibrant and saturated, significantly improving colour reproduction quality in HDR content. Despite the limited brightness, the wide colour range allows for richer and more realistic shades.

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.

The colour reproduction in the P755 in "Cinema" mode, although it is the best factory setting, leaves much to be desired. The biggest issue is the white balance, where the chart clearly shows a spike in the red colour and a drop in the green colour. This leads to a shift in colours towards red, causing the colours on the screen to appear less natural and may look incorrect, especially in scenes with a white or neutral background. This is confirmed by the "Colour Checker" test, which reveals that the colours are indeed shifted towards red, affecting the realism of the image and reducing the perception of colour depth. In terms of contrast, the gamma chart analysis shows significant fluctuations, particularly in the dark areas of the image, where values drop below the optimal level of 2.4. As a result, darker areas may be displayed brighter than they should be. Additionally, the EOTF curve, responsible for brightness reproduction, sits slightly above the reference curve. The graph shows a slight increase in brightness to about 50%, after which there is only a minor drop. This leads to excessive brightness enhancement in the mid-range of the image and may result in loss of detail and distortion in brighter scenes.

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.

After calibration, the colour reproduction on the television significantly improves when it comes to SDR content. The colour curves are now close to the ideal value, and the gamma is more stable. Although the dip at the beginning of the graph to the values is still present, the overall accuracy of colour reproduction is much better. The “Colour Checker” test shows that most colour samples have errors below level 2, indicating improved colour fidelity. A few deviations are present, but generally, the colours are now more realistic and consistent with reality.

Calibration also brings improvements in HDR content. The white balance has been corrected, translating to more natural colour reproduction. The EOTF curve, although now closer to the reference curve, still shows a slight boost in brightness at the beginning of the graph. This leads to minor distortions in very bright scenes, but the overall tonality and detail have been enhanced. Dynamic tone mapping works more effectively, improving image quality in bright areas and preserving more details.

Although the image from the device does not achieve full perfection, calibration brings significant improvement. After adjusting the settings, the television performs much better, offering more realistic and accurate colour reproduction in SDR and HDR content. While some shortcomings can still be noticed, calibration effectively eliminates many previous issues, ensuring better image quality and more natural colours.

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.

The “Gradual Smoothing” function works quite well, effectively eliminating visible boundaries between different shades of the same colour. Thanks to it, tonal transitions are smoother. Unfortunately, this function is not available in HDR mode, which can affect the quality of tonal gradation in higher dynamic range materials.

In the case of image scaling, the television does not perform its best. There are noticeable edge cut-offs, particularly evident on the model's figure and the branches of trees. The blurring of details in these areas affects the overall sharpness of the image. This may be noticeable when watching content in a lower resolution. Additionally, SD quality image is displayed with slight cropping at the top as well as the bottom.

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.

The television offers decent, though not perfect, results in terms of motion smoothness. In the case of movies, the television has a "Flicker Reduction" feature that allows for adjustment of motion smoothness on a scale from 1 to 10. With this option, we can tailor the image appearance to cinema or more theatrical preferences (with lower or higher speed).

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.

The device offers a range of features useful for gamers, such as ALLM (Auto Low Latency Mode), VRR (Variable Refresh Rate), Dolby Vision for gamers, and Game Bar. ALLM automatically switches the TV to low latency mode, significantly improving responsiveness to commands from the controller and minimising input lag. VRR synchronises the screen refresh rate with the number of frames generated by the console, eliminating the tearing effect and providing smoother gameplay. Dolby Vision for gamers enhances picture quality by offering better colour and contrast reproduction in games that support this format. The Game Bar feature allows quick access to game settings and monitoring of key parameters such as response time.

However, the TV has some limitations. The 60 Hz panel prevents the display of signals with higher refresh rates at different resolutions, which may affect the fluidity of the image in dynamic games. Additionally, the lack of support for G-Sync technology for PC may impact the quality of gameplay on a computer. It is also worth noting that the HGiG mode, which aims to improve image quality in HDR games, does not work correctly on this model, negatively affecting the visual experience in HDR-supported games.

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.