It's tough to improve the picture quality of OLED TVs, but LG did it again. Just barely.

LG's 2019 C9 OLED TV is the best-performing TV I've ever tested at CNET. In 2018 I said the same thing about the C8 and in 2017 I said the same thing about the C7. Year after year, TVs based on organic light-emitting diode tech deliver the best picture quality you can buy, and the C series showcases LG's best efforts to perfect it.

Granted, the differences in image quality between the new C9 and last year's sets are tiny -- arguably better HDR, a hair more effective processing and milliseconds-quicker gaming lag -- but still enough to propel it to technical superiority. For most buyers, however, those differences won't be worth the steeper price of the C9 compared to the 2018 models, including my current Editors' Choice B8.

In my side-by-side comparison tests, the C9, C8 and B8 all outperformed the best LCD TVs I had on-hand, but the 2019 TV season is just getting warmed up. I have yet to test any 2019 Samsung, Sony or Vizio TVs, including Sony's own OLED models. Any of their flagship sets could conceivably upset the C9 and take the crown, and the LG B9, which lacks the video processing chops of the C9, could once again deliver the best OLED TV value when it debuts later this summer. And as usual, expect big price cuts on all TVs starting this fall.

In the meantime, the OLED C9 sets another staggeringly high bar for image quality. Once again, it's up to the rest of the TV market to try to reach it.

Quick LG C9 OLED TV takeaways

• It's available in 55-, 66- and 77-inch sizes, but the 77-incher is a lot more expensive than the others. At that size, most buyers should look at 75-inch LCD TVs first.
• Currently the 65-inch C9 costs $1,000 more than the B8 and $700 more than the C8. The 55-inch C9 costs $900 more than the B8 and $600 more than the C8. Those prices may shift around, but until the C9 gets a drastic price cut, the B8 from 2018 is still the best value.
• Image quality was very slightly better than the C8 and B8 from 2018, but they were so close that all three scored a "10" picture quality rating.
• Compared to the C8, the C9 will get Alexa built-in, Apple AirPlay 2 and offer more HDMI 2.1 extras, including eARC and Auto Game mode and Variable Refresh rate. Otherwise they're basically the same.
• OLED display technology is fundamentally different from the LED LCD technology used in the vast majority of today's TVs, including Samsung's QLED models.
• The best LCD TVs I've reviewed so far, the Samsung Q9 QLED and the Vizio PQ-65F1, scored a "9" in image quality. At times they were brighter in HDR than the OLEDs, but otherwise the OLEDs' images were superior in almost every way.
• All OLED TVs are more subject to both temporary and permanent image retention, aka burn-in, than LCD TVs. We at CNET don't consider burn-in a reason for most people to avoid buying an OLED TV, however. Check out our guide to OLED burn-in for more.

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Thinning, winning design

Not much has changed with LG's design, but that's not necessarily a bad thing. The panel itself is still vanishingly thin when seen from the side, about a quarter-inch deep, with the typical bulge at the bottom that juts out another 1.75 inches. That bulge houses the inputs, power supply, speakers and other depth-eating TV components.

From the front there's less than a half-inch of black frame around the picture itself to the top and sides. Then there's a bit more below, but no trace of silver, no "LG" or any other logo at all. This is TV at its most minimalist.

The stand is nicer than last year to my eye, with its angled edges and medium width across the bottom of the screen. New this year it's more heavily weighted on the rear to (I presume) better resist tipping forward.

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Familiar smart TV, voice and remote

LGs webOS menu system feels nice and snappy, but it's basically unchanged from last year. It still lacks the innovative extras and app-based setup of Samsung's Tizen system, and falls well short of the app coverage of Roku TV or Sony's Android TV. If you want more apps, your best bet is to get an external streamer, although only two, the Apple TV 4K and Amazon Fire TV Stick 4K, can support Dolby Vision and Dolby Atmos. Meanwhile LG's apps for Netflix, Amazon and Vudu all support Dolby Vision and Dolby Atmos, so using the TV's built-in apps gets you the highest-quality video and audio from those services, no external streamer required.

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The remote is the same as last year too. I like using its motion control to whip around the screen, something that's particularly helpful when signing into apps or searching using an on-screen keyboard. The scroll wheel is also great for moving through apps, like those seemingly infinite thumbnail rows on Netflix and Amazon.

Press the mic button and you can summon Google Assistant. It can do all the usual Assistant stuff, including control smart home devices, answer questions and respond via a voice coming out of the TV's speakers. It also integrates TV-specific commands, including a well-implemented voice search. I said "show me comedies" while watching Netflix and a list of TV shows and movies appeared along the bottom, including results from the current app (comedies on Netflix) as well as across different apps (including Prime Video, Fandango, Hulu, Vudu and Google Play) and YouTube videos.

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LG will soon become the first TV maker to build in a second major voice assistant, Amazon's Alexa, available by pressing and holding the Prime Video button. The feature will roll out in a software update due later this year, and won't be available on 2018 or earlier LG sets.

Also coming later this year is support for Apple's AirPlay 2 system, letting the TV function as a display for TV shows, movies, photos and web pages with an iPhone, iPad or Mac as the controller, and for HomeKit, which will let you control the TV using Apple's Home app or by talking to Apple's assistant Siri. The Apple features are similar to those coming to 2019 Vizio and Sony TVs, while the full Apple TV app will launch first on Samsung TVs.

Key TV features

Display technology	OLED
LED backlight	N/A
Resolution	4K
HDR compatible	HDR10 and Dolby Vision
Smart TV:	webOS
Remote:	Motion

Features and connections

OLED is not your father's LCD TV. LCD relies on a backlight shining through a liquid crystal panel to create the picture. In an OLED display, each individual subpixel is responsible for creating illumination. That's why OLED is known as "emissive" and LED LCDs are called "transmissive" displays, and it's a big reason why OLED's picture quality is so good.

Once again the C9 panel has the same basic characteristics, including light output and color gamut, of previous years, so the main upgrade is in processing. There's a new A9 Gen 2 chip with a "deep learning algorithm" that, among other claims, better adjusts the picture for room lighting.

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The 2019 OLED models also include the latest version of the HDMI standard: 2.1. That means their HDMI ports can handle 4K at 120 fps, support enhanced audio return channel (eARC) as well as two gamer-friendly extras: variable refresh rate (VRR) and automatic low latency mode (ALLM, or auto game mode). Check out HDMI 2.1: What you need to know for details. I didn't test any of these features yet for this review.

The selection of connections is top-notch. Unlike many of Samsung's sets, this one actually has an analog video input for legacy (non-HDMI) devices, although it no longer supports analog component video. New for 2019 there's a dedicated headphone/analog audio output and WISA wireless audio support.

• Four HDMI inputs with HDMI 2.1, HDCP 2.2
• Three USB ports
• Composite video/audio input
• Optical digital audio output
• Analog audio 3.5mm headphone output
• RF (antenna) input
• RS-232 port (minijack, for service only)
• Ethernet (LAN) port

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