TCL P755 vs TCL A400 PRO

The TCL P755 delivers an average HDR experience, with a maximum brightness of just under 300 nits. This limitation affects the intensity of bright areas in HDR content, reducing the contrast impact, as bright elements may appear less pronounced. However, the TV compensates with an impressive 93% coverage of the DCI-P3 colour gamut, which brings vibrant, saturated colours that enhance the quality of HDR content. Despite the brightness cap, the extensive colour range enriches hues, providing a more lifelike and visually engaging viewing experience.

The TCL A400 Pro is a moderately bright TV. Its peak brightness reaches about 600 nits. That level already allows for a real HDR effect and in many movies it does produce a noticeably more attractive picture than SDR. However, it is not a level that overwhelms by brightness alone. The A400 Pro is not one of those TVs that "attack" the viewer with a powerful flash in every dramatic scene. The biggest limitation is visible with small bright elements on a dark background. Due to rather aggressive control of the dimming zones, 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. That said, this is not done without reason. The A400 Pro does this to keep blacks as deep as possible and to limit haloing around bright objects. It's a deliberate compromise: the TV more often chooses deeper blacks over maximally bright, point-like highlights. On one hand this is understandable, especially with a limited number of dimming zones, but on the other hand you should be aware that the HDR effect will not always be as strong as the peak brightness alone would suggest.

On the plus side, the colors are worth noting. The PFS LED filter used here, marketed by the manufacturer as QLED, produces suitably saturated colors. Our measurements showed about 94% coverage of the DCI-P3 gamut and about 74% of BT.2020, which is a solid result for this class.

In Cinema mode, the colour reproduction on the TCL P755, while set to the best factory configuration, falls short of ideal accuracy. The primary issue is the white balance, where the red component is notably elevated and the green is reduced. This imbalance shifts colours towards red, making them appear unnatural, particularly in scenes featuring white or neutral tones. This issue is highlighted in the Colour Checker test, which shows a discernible red bias affecting the realism of the image and diminishing the perception of colour depth.

Examining contrast performance, the gamma graph analysis reveals notable inconsistencies, especially in darker areas, where values dip below the target level of 2.4. Consequently, shadows and darker sections are displayed brighter than intended, impacting overall contrast. Furthermore, the EOTF (Electro-Optical Transfer Function) curve, essential for accurate brightness representation, veers slightly above the reference curve. The data shows a boost in brightness up to around 50% before a gradual levelling off. This creates excessive mid-tone brightness, which can lead to loss of detail and some distortion in brighter scenes, ultimately affecting the clarity and immersion of the viewing experience.

As standard, we carried out color measurements in the best-calibrated mode, Filmmaker Mode, the one that is supposed to be closest to the creators’ intent. The A400 Pro, of course, also offers other picture modes, but in practice they suffer from much larger color errors and alter the image character more strongly. We won’t go into those modes in detail in this part of the test. So how does the factory color reproduction perform? In short: really very well. In fact, looking at our measurement results, it’s excellent. Both the white balance and the luminance response were set surprisingly precisely. The errors were so small that during testing we genuinely rubbed our eyes in disbelief. Such good out-of-the-box settings don’t happen often, even in TVs operating in Filmmaker Mode. All the more reason to praise TCL, because the A400 Pro right out of the box can produce an image very close to how the source material should look. The results were so good that you could easily think someone had already paid extra attention to that unit and tried to calibrate it.

Our nitpicking really comes down to just one thing. In SDR content the image was slightly brighter than the reference for a dark room, because the factory gamma was set closer to 2.3 than to 2.4. It’s not a big error and most viewers probably won’t even notice it.

However, it should be noted that we’re talking about our specific review sample. With factory colors there can always be some variation between units, production batches, or screen sizes. So we don’t assume that every A400 Pro will look identical straight out of the box.

Post-calibration, the TCL P755 delivers a markedly improved colour performance for SDR content. The colour curves now align closely with ideal values, with a more consistent gamma stability across the range. While a slight drop at the beginning of the gamma curve persists, the accuracy in colour reproduction is significantly enhanced. The Colour Checker test reveals most colour samples are now under an error threshold of 2, showcasing much-improved colour fidelity with only minimal deviations, resulting in colours that feel notably more authentic to life.

HDR content benefits from these calibration adjustments as well. White balance corrections lend a more natural tone, with colours appearing more balanced overall. The EOTF curve, while nearer to the ideal reference line, still features a mild brightness elevation at the start, which can cause minor distortions in exceptionally bright scenes. However, overall tonal quality and detail resolution have both improved. Tone mapping also performs more effectively, enhancing detail in bright regions while maintaining better image accuracy.

In summary, while calibration does not bring flawless performance, it makes a substantial difference in the P755’s visual quality. Following these adjustments, the television provides a more accurate, realistic viewing experience in both SDR and HDR content, smoothing out many of the previous colour inconsistencies for a more visually engaging result.

Despite its excellent factory tuning, we couldn't resist checking how the TCL A400 Pro would respond to a professional calibration. Since the starting point was so good, we were even more curious whether we could squeeze even more out of this TV. And here we have to boast: we managed to bring our unit to absurdly low color errors. Results below 1 are something you don't see every day, even on very good TVs. Such results are more often associated with professional reference monitors than with a lifestyle TV for the living room. In terms of white balance and color reproduction, the A400 Pro after calibration simply performed outstandingly. The only thing we can pick at after a deeper analysis concerns the brightness behavior. The TV can manipulate luminance levels depending on the content being displayed, and quite often the image is a bit darker than it should be according to the standard. This most likely stems from the way the Mini-LED backlight and local dimming algorithms work in this model. However, that doesn't spoil the overall impression, because in terms of color precision alone the A400 Pro after calibration reached a level we really didn't expect.

The "Gradual Smoothing" function on the TCL P755 performs effectively, reducing visible boundaries between shades of the same colour and creating smoother tonal transitions. Unfortunately, this feature is unavailable in HDR mode, which can impact the quality of tonal gradations in high dynamic range content.

In terms of image scaling, the television shows some limitations. There are visible edge cut-offs, especially noticeable around figures and tree branches, which result in some detail blurring and a reduction in overall image sharpness. This is particularly noticeable when viewing lower-resolution content. Additionally, SD-quality images display a slight crop at the top and bottom, which may further impact viewing for standard-definition content.

Digital video processing is unfortunately one of the weaker points of the TCL A400 Pro. That doesn't mean the TV performs badly, but it's hard to call it anything clearly above standard. The upscaling itself is adequate: edges are smoothed fairly well, the image doesn't look overly sharp or pixelated, and lower-quality content can be watched without major discomfort. At the same time the overall look is slightly soft and it lacks the precision that the best image processors in more expensive TVs can deliver.

Much worse, however, is its handling of tonal transitions caused by heavy compression. TCL equipped the A400 Pro with a "Gradual Smoothing" feature that in theory should reduce visible color banding and artifacts in lower-quality content. In practice 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's best to leave this feature off. The A400 Pro handles basic image scaling decently, but if you often watch heavily compressed content with visible posterization, this model won't be one of the best choices.

The TCL P755 delivers satisfactory, though not flawless, motion smoothness. It includes a "Flicker Reduction" feature for films, allowing users to fine-tune motion smoothness on a scale from 1 to 10. This setting offers flexibility in tailoring the image to cinematic or more theatrical preferences, adjusting for a slower or faster appearance according to personal viewing taste.

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 used by most consoles today, as well as many sports broadcasts and high-frame-rate content. In this range the TV performs quite well. Motion clarity is really good, especially after properly configuring the motion smoothing. The "Motion Clarity" feature improves smoothness. Its settings include two sliders that let you tailor the motion smoothing to your preferences — separately for lower- and higher-frame-rate material. That way you can achieve either a more cinematic look or a noticeably smoother picture. If you don't want to tweak settings manually, you can use presets such as low, medium, high, cinema, or nature.

The TCL P755 comes equipped with gamer-oriented features like ALLM (Auto Low Latency Mode), VRR (Variable Refresh Rate), Dolby Vision for gaming, and a Game Bar. ALLM automatically activates low latency mode to enhance response times and reduce input lag, while VRR syncs the screen refresh rate with the console's frame output, minimising screen tearing for a smoother gaming experience. Dolby Vision for gamers brings improved colour and contrast for compatible games, and the Game Bar allows easy access to essential settings like response time.

However, the 60 Hz panel limits the display to this refresh rate across resolutions, which may impact the fluidity in high-motion games. The absence of G-Sync also affects PC gamers, as gameplay on computers lacks this technology's extra smoothing. Notably, HGiG mode, meant to optimise HDR game visuals, is not fully functional on this model, which slightly detracts from the HDR gaming experience.

When it comes to features for gamers, the TCL A400 Pro performs excellently. The TV has practically everything you can expect from a gaming TV today: 4K support at high refresh rates, VRR, ALLM, correct implementation of HDR formats in games, including Dolby Vision, and HGiG. Because of that it works well with both next-gen consoles and PCs. Another plus is the inclusion of a Game Bar, a special panel with the most important settings for gamers. From it you can quickly check basic signal information, refresh rate, and active features, and also adjust the look and behavior of some settings to your own preferences. This is 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 complain about 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 functions as eARC. In practice this means that if someone wants to connect two next-gen consoles and a soundbar, they may hit some limitations. In that scenario you'll have to either swap devices or use extra equipment, for example an AV receiver or a soundbar with HDMI inputs. Despite this, it's hard not to rate the A400 Pro very highly as a gaming TV. The gaming feature set here is really powerful.