I Was Wrong: RGB LED Isn't the Future of TVs

Last year, I sang the praises of RGB LED TVs. The first model I tested, the $30,000 Hisense 116UX , blew me away with its blindingly bright picture and the widest color range I'd ever seen. I was so impressed that I thought RBG LED technology could be the future of TVs .

I'm not afraid to admit when I'm wrong. I've tested a handful of RGB LED TVs this year, including the Hisense UR9 , the Samsung R95H , and the Sony Bravia 9 II , and with each one, I've noticed some problems that might be fundamental to RGB technology. They could get fixed or smoothed over in time, but for now, I can confidently say that RGB LED is not, in fact, the future of TVs. OLED is still the best way to go for a truly premium experience, and conventional mini-LED QLED has proven it can keep up with RGB LED in light output and color range.

What Is an RGB LED TV? (And How It Differs From OLED)

TVs come in a few different types based on their panel and backlight technology. LED TVs use a liquid crystal display (LCD) panel that emits no light on its own, but is backlit by light-emitting diodes (LEDs). Some LED TVs use a large number of very small LEDs, with zones that can dim or brighten to improve contrast. This is called mini-LED. Other LED TVs use blue LEDs with a special layer of quantum dots on the LCD panel that can bend blue light to produce a wider range of color than a typical, white-backlit LED TV. This is called QLED. Most high-end LED TVs are mini-LED QLED models that combine the technologies.

RGB LED TVs also use an LCD panel and LED backlight, but instead of just white or just blue lights, they use clusters of red, green, and blue LEDs. These colors can be adjusted individually to expand the panel's color range. A red object can look much more saturated than the panel alone can show when the LEDs lighting it can brighten red while dimming blue and green. These are technically mini-LED TVs, but their multi-color lighting is a big departure from both conventional LED and QLED TVs.

There are also organic light-emitting diode, or OLED , TVs. Despite the similar name, OLED TVs are completely different from other LED TVs. They forgo an LCD panel and LED backlight in favor of a single OLED panel that can both change color and emit light at the per-pixel level. They can be incredibly thin and look fantastic, but they generally can't put out as much light as high-end LED TVs.

In theory, RGB LED seems like the most promising panel technology, since it can get much brighter than OLED and produce a wider range of colors. That theory bears out in empirical tests, but it doesn't hold up in regular TV viewing. RGB LED TVs look incredible on paper, but not nearly as great when you're on the couch.

The Gap Between Lab Tests and Real-World Viewing

The above charts show color levels for the RGB LED Samsung R95H compared against the BT.2020 color space with an HDR10 signal in Movie mode. Both charts use the same data, but the CIE31 chart shows the full range of human vision as absolute values, while the CIE76 chart adjusts the colors to better reflect how we perceive color differences. The R95H covers 89.98% in CIE31 and 92.67% of CIE76. That's more than any other TV I've tested. 

These are genuinely impressive results, and the colors the TV displayed when I measured them were among the most vivid I've seen. In fact, every RGB LED TV I've tested has given me incredible numbers in terms of color range. None have been able to meet their manufacturers' claims to fully cover the BT.2020 color space, but they've come close.

That said, these numbers don't tell the whole story. RGB LED TVs have a big gap between testing and real-world viewing performance that conventional LED, QLED, and OLED TVs don't.

The Backlight Compromise That Dulls Real Colors

I test TVs using specialized equipment: a Klein K-10A colorimeter that precisely measures light and color, a Murideo SIX-G 8K signal generator that sends consistent test patterns to the TV, and Portrait Displays' Calman software to control the signal generator and process the colorimeter's data.

I go through a variety of test patterns and measurements, but the most important ones are simple, flat fields of white, red, green, blue, cyan, magenta, and yellow. These big, glowing blocks let me see just how bright a TV can get, how accurate its white point is, and how wide (and accurate) its color range is. For mini-LED, QLED, and OLED TVs, this process works very well. RGB LED TVs are another story.

Yes, RGB LED TVs can produce some of the widest color ranges I've measured. They're extremely good at it when showing big fields of flat color, because they can just boost and dim their lights as needed to really push their limits. However, when there's a complex image on the screen, those pumped-up LED colors can tint and warp the edges of adjacent objects of different colors. 

This is called color bloom, and it's a more complex and potentially distracting version of the light bleed that all LED TVs with local dimming show. Light bloom just produces a consistent haze along high-contrast edges. Good TVs can minimize this effect, and even when it's apparent, it usually doesn't detract much from the viewing experience. Color bloom takes that light bloom and tints it with color. Instead of just a light haze where bright objects meet dark backgrounds, it can mess up colors wherever clashing hues meet. Color bloom can be a big problem, but I haven't actually seen much of it on RGB LED TVs because the ones I've tested have measures in place to prevent it. Unfortunately, this is a case where the cure is almost as bad as the disease.

To prevent color bloom, RGB LED TVs seem to err toward neutral white when there's any question of conflicting colors close together. The red, green, and blue LEDs light up together to produce balanced white light with no risk of tinting the image. For a big red curtain that takes up most of the screen, a backlight can boost the red, making it look even more intense. For a bouquet of many different flowers, the backlight will stay white so the different colors look accurate. The end result is a picture that simply isn't as vivid as formal testing indicates. 

Remember QLED? Those TVs use blue light and a layer of quantum dots on the LCD to produce a wider color range than the LCD can show on its own. RGB LED TVs don't have a quantum dot layer because quantum dots specifically react to blue light and won't work with multiple colors. This is why RGB LED TVs default to white to prevent color bloom. This is also why, when showing most video content, they can't actually form the wide colors they're able to when showing flat, consistent color fields.

I've seen this play out in every RGB LED TV I've tested since the Hisense 116UX. I didn't notice it as much on the 116UX because it could get much brighter than any other TV I've tested, reaching 5,889 nits with a 10% white field, compared with a maximum of 3,654 nits on the Sony Bravia 9 II and 2,267 nits on the Samsung R95H. Luminance can heavily affect the perceived vividness of color, and the 116UX's blinding output helped mask issues that are much more apparent on other RGB LED TVs. Also, keep in mind, it's a 116-inch, $30,000 TV, so it's pretty far outside the realm of feasibility for most people.

Beyond Color: Bad Off-Angle Viewing and Heavy Haze

I've been seeing two other big problems from RGB LED TVs, separate from the limited colors that come with preventing color bloom. First, while hue-warping bloom is kept to a minimum, these TVs still show significant light bloom. When viewed straight-on, edges between bright and dark objects usually show a bit more of a (neutral, white) glowing aura than other high-end mini-LED TVs. Once you start moving off-axis, away from the sweet spot of the center of the screen, that bloom explodes. Off-angle viewing consistently causes haze on RGB LED TVs, usually starting at only 10 or 15 degrees. This is on top of desaturation that further crushes the range of colors you can see on the screen.

Off-angle viewing can be hit-or-miss for TVs in general, and cheap and midrange LED TVs often show duller colors and lower contrast when viewed from the side. Higher-end mini-LED and QLED TVs fare much better but can still show it, while OLEDs are generally consistent and vibrant no matter how you look at them. It's been consistently bad on every RGB LED TV I've seen, though.

SQD-Mini LED Proves RGB LED Isn't Even Necessary

TCL has proven that conventional mini-LED QLED TVs can reach the same levels of color and brightness as RGB LED TVs. The company's SQD-Mini LED TVs use smaller, brighter, and more focused LEDs, with an improved quantum dot layer, to produce a color range equal to that of RGB LED TVs. When I tested TCL's X11L in March, I saw potential in its impressive numbers, though it was too expensive to recommend wholeheartedly.

But just a few months later, TCL's QM8L blew all of my expectations out of the water. The QM8L is incredibly bright, to the point that it earned a Lab Award for brightest TV . Its color range is slightly better than the X11L and even the Bravia 9 II, covering 91.34% of BT.2020 (CIE76). And it's also only $2,000 for 75 inches.

Why OLED Remains the Undisputed Picture Quality Champion

For as advanced and impressive as LED TV technology has become, I still find myself going back to OLED for the absolute best viewing experience. OLED TVs generally aren't as bright as the brightest LED TVs, and their measured color levels don't come close to what RGB LED and SQD-Mini LED TVs can do, but their colors stay consistent no matter what you show on them. They don't have a hint of bloom of any kind thanks to their pixel-level light control, and they look about as good when viewed from the side as they do straight-on. When you're actually watching something on them and not solely looking at the numbers, their pictures are superlative.

The Samsung S95H is the best OLED TV I've tested to date, earning an Editors' Choice award and a Lab Award for fastest gaming performance . It's incredibly bright for an OLED TV (1,634 nits 18% field, 2,460 nits 10% field), though it isn't as bright as any of the RGB LED TVs I've tested. It also only covers 88.49% of BT.2020 (CIE76) when the RGB LED TVs all easily break 90%. Despite these numbers, the S95H looks much better than Samsung's own R95H—and every other RGB LED TV I've tested—in every way. Plus, it's only about $100 more than the R95H.

Even midrange OLED TVs look fantastic, though. The LG Evo C6 , another Editors' Choice winner, is by far the dimmest of any TV I've mentioned here (1,015 nits 18%, 1,552 nits 10%). But it still looks great from every angle, with accurate and well-saturated colors. Plus, it has a full suite of gaming features, including 165Hz VRR, AMD FreeSync Premium, and Nvidia G-Sync. It's also much cheaper than any of the RGB LED TVs I've looked at; you can get a 65-inch model for about $1,800, and that price will reliably drop to around $1,500 during Amazon Prime Day and other sales. Heck, my LG Evo C4 is two generations older and not as bright, and I adore it. It's the best-looking TV I've owned.

RGB LED TVs might still prove viable if they are able to overcome their significant limitations. For now, though, if you want the best picture possible, OLED TVs are still your best bet.

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