LG OLED C6H (TANDEM OLED) vs Sony BRAVIA 2 II (S25M2)

And it's with HDR that the Tandem OLED panel shows its biggest advantage. The C6H's brightness is simply very high and in our measurements it hovered around 1900–2300 nits in most movie scenes. That's already a level at which bright highlights, the sun, or small light sources can look truly spectacular. The biggest impression on us, however, was the fifth scene from the film The Meg. It is exceptionally demanding for OLEDs because practically the entire screen is very bright. Even so, the C6H reached about 1650 nits there. For comparison, the regular C6 with a classic WOLED panel delivered around 600–700 nits in the same spot. So we're talking about more than double the brightness, and in places the difference approaches threefold. That is probably the best example of what Tandem OLED brings. It's not just a higher result on a small test patch. The C6H can sustain very high brightness even when much more of the screen is lit. Thanks to that, HDR has a significantly greater dynamic range and in this respect the C6H is much closer to flagship OLEDs than to typical mid-range models.

Colors

Tandem OLED also brings improvements in color. DCI-P3 coverage remains practically full at about 99%, while in the much wider BT.2020 gamut we measured roughly 82–83%. That's about 7 percentage points more than the regular C6. In everyday use this won't be a visible difference in every scene, since most films don't use such a wide gamut. However, when very heavily saturated colors appear, the C6H already has noticeably greater capabilities, especially in reds. Reds benefit the most, becoming deeper and more saturated. It's still not at the level of the best QD-OLED panels or SQD TVs, but for a WOLED panel the result is really very good.

Sony Bravia 2 II is not a very bright TV and unfortunately that is immediately apparent in HDR. In our measurements brightness stayed around 300 to 330 nits, which is definitely too low for the brightest parts of the picture to look truly impressive. In practice HDR here does not differ that much from ordinary SDR. Bright highlights, the sun, or lamps are of course visible, but they lack the intensity you would expect from HDR material. The Bravia 2 II therefore performs much better with regular SDR content, and it is in that use case that its limited brightness will be least noticeable.

Color gamut coverage

Sony Bravia 2 II also doesn't impress when it comes to colors. The TV doesn't use any additional gamut-expanding filter, such as the quantum dots found in QLED TVs or a PFS phosphor layer. In our measurements DCI-P3 coverage was about 78%, and the very wide BT.2020 around 57%. That's definitely too little to talk about truly saturated colors in HDR content. More intense reds, greens, or turquoise hues will simply be less striking than on TVs with an expanded color gamut. The Bravia 2 II therefore fares much better with standard Rec.709, the gamut used for movies, series, and TV in SDR.

Right out of the box the LG C6 is pretty well calibrated, especially if you select Filmmaker mode. In SDR content the white balance is quite good, although as brightness increases it starts to show a slight lack of red. The picture becomes a bit cooler as a result, but not enough to be very noticeable during normal viewing. More is happening in the luminance response. Gamma is a bit low and, instead of holding at 2.4, it sits closer to 2.1–2.2 across much of the range. In practice the C6 slightly brightens the midtones. Shadows are therefore more readable, but the image loses some depth compared with how it should look in a dark room.

The situation is a bit more interesting in HDR. The start of the grayscale looks very good, but from roughly 20–30% brightness the white balance begins to drift increasingly. As brightness rises, red increases and blue becomes noticeably lacking. In the brightest areas the difference is already substantial and also affects the reproduction of some colors. The EOTF curve itself is, however, fairly well followed over most of the range. The C6 only tends to slightly brighten the image, which we also saw during our film comparisons. The largest deviation appears around the brightest sections, where the TV begins to map the signal to the panel’s capabilities.

The out-of-the-box Filmmaker mode in HDR is therefore not perfect, but overall it performs well. The biggest room for improvement is the white balance, especially at high brightness.

Out-of-the-box color reproduction in Cinema mode was really good, at least for ordinary SDR material. The Bravia 2 II had a slight tendency to boost reds, so some colors skewed a bit warmer, at times with a faint pinkish tint. However, it wasn't a major fault, and during normal viewing the picture still looked quite natural. There was a bit more going on with image brightness. Looking at the gamma trace, you can see Sony doesn't stick exactly to the reference value. The darkest parts are slightly lifted, while as brightness increases the gamma gradually rises and a larger portion of the image becomes darker than it should. That said, the difference isn't large enough to seriously interfere with everyday viewing. Overall, SDR straight out of the box performs pretty well.

The situation is much worse in HDR. We already mentioned the limited color gamut, but the Bravia 2 II also manipulates image brightness quite aggressively here. The EOTF curve sits below the reference for a large part of the range, which means the TV renders most midtones and brighter parts of the scene darker than the source material intends. Only toward the very end of the range does the curve flatten out, as the panel reaches the limits of its capabilities. Combined with a peak brightness of around 300 nits, this results in HDR that not only lacks punch but can simply look too dim.

LG TVs have been very receptive to calibration for years, and the C6 is no exception. After correction we were able to set the white balance almost perfectly, and most color errors (Delta E) fell below 3, often even around 2. In practice this means very accurate color reproduction in both SDR and HDR. The only curiosity showed up with the HDR luminance response. On the standard EOTF chart everything looks nearly perfect and at first glance it would be hard to fault anything. Only when we measured the TV’s behavior using filters based on actual movie scenes did it become apparent that the C6 has a slight tendency to artificially boost image brightness.

It’s not a huge difference and many people may even take it as a positive, since HDR looks a bit more striking because of it. From the perspective of fidelity to the source material, however, this isn’t ideal — some scenes are simply a bit brighter than the filmmaker intended. Interestingly, this is rather atypical for LG. In previous generations LG TVs usually adhered closely to the reference picture curve after calibration. With the C6 we’re still very close to the standard, but that subtle brightness "boost" can indeed be noticed in movies and TV shows.

Calibration did a lot for the Bravia 2 II, especially with SDR content. Above all, we were able to even out the white balance and tidy up the gamma, which now sticks much closer to reference values. As a result, the picture no longer has the previous pink tint, and the brightness of individual areas is much better balanced. You can also see this in the color errors, which dropped to a very low level after calibration (with minor issues in the most saturated reds).

We also partially tamed the Bravia 2 II in HDR, particularly in how the TV manages image brightness. However, there is one thing no calibration can fix: the panel's inherent limitations. The narrow color gamut means the TV physically cannot reproduce the most saturated colors present in HDR content. On top of that, the IPS panel's low contrast leaves darker scenes veiled by a grayish glow, causing colors to lose some of their depth. So we can improve how the Bravia 2 II uses its capabilities, but unfortunately we can't overcome the panel's fundamental limits.

Here the LG C6 has taken a really big step forward. The TV uses the same processor found in the flagship G6, and in terms of image processing the two models are very similar. That's a big plus, because in this area LG's processor this year performs excellently. The "Smooth Gradation" feature works especially well. With heavily compressed material it can effectively hide ugly banding and artifacts that often appear, for example, in lower-quality streaming. It's best to leave it on the "Low" setting. That way the improvement is noticeable, and the TV doesn't yet start blurring fine details. Higher levels smooth the image more, but can start to remove some of the natural texture of objects on screen. The upscaling itself also performs very well. Lower-resolution material is properly sharpened, edges look clean, and the processor quite effectively reconstructs fine details. In this respect the C6 is already very close to LG's best TVs, and the differences compared with the G6 are small.

Upscaling in the Bravia 2 II performs quite well, and in that respect the TV maintains the standard Sony has accustomed us to. Lower-resolution content is sensibly scaled to 4K, with the image slightly smoothed and without over-sharpening edges. It’s a different story when it comes to improving content with visible compression. That’s handled by the "Digital Noise Reduction" feature, which on the "High" setting can indeed smooth out some ugly tonal banding. The problem is it does so fairly aggressively, removing a lot of fine detail along with the imperfections, including natural film grain. Moreover, when there’s more motion on screen its effectiveness drops significantly and the improvement becomes minimal. So we generally avoided using this feature in everyday viewing.

The C6H with a Tandem OLED panel can also operate at refresh rates up to 165 Hz. PC gamers will get the most use out of that, of course, because for consoles, movies, or sports we’re still talking about a maximum of 120 Hz. The panel itself performs excellently in motion. OLED pixels respond virtually instantly, so even with fast-moving objects you don’t see the typical motion blur behind them. The image stays clean whether you’re watching sports or playing fast-paced games.

If you care more about smoothness than motion clarity, TruMotion is available. LG lets you adjust two parameters separately. De-Judder works mainly with films and series shot at 24 fps and helps reduce the judder typical of them. De-Blur, on the other hand, is intended for 50/60 fps material, so it’s especially useful when watching sports or TV.

The Bravia 2 II uses a 60 Hz panel and, given its capabilities, handles motion quite well. However, keep in mind this is a basic panel, and its limitations are already noticeable, especially with sports. The TV cannot interpolate 50/60 fps content to a higher refresh rate, so it can't further improve the sharpness of fast-moving objects. For movies and series, you get a standard motion smoother that can reduce the characteristic judder of material shot at 24 fps.

The C6H offers basically a full package of gaming features. On consoles we can easily use 4K at 120 Hz, while PC users can push the refresh rate up to 165 Hz. The TV also supports VRR from 40 to 165 Hz, ALLM and a proper implementation of HGiG. Dolby Vision is also available in game mode, which remains a significant advantage for Xbox owners. We can view all the key information in the Game Bar, which provides quick access to VRR settings and current signal parameters. The OLED tandem therefore doesn't change the actual feature set for gamers, but with such high panel brightness HDR games can make an even bigger impression. Functionally, the C6H is simply a very complete TV for console and PC.

The Bravia 2 II is not a TV particularly well suited for gaming, and the feature list makes that clear pretty quickly. You basically only get automatic low-latency mode (ALLM) and a simple Game Bar where you can view basic signal information and change a few settings. But that's where the list of advantages ends. The TV doesn't support VRR or 120 Hz (not even at lower resolutions), and on top of that it has problems with a proper implementation of the HDR HGIG format. It can, of course, be used for occasional console gaming, and thanks to low input lag controls stay responsive, but if you're mainly looking for a TV for gaming, the Bravia 2 II will simply be a very limited choice.