The LG C9 OLED is an excellent TV. Like all OLED TVs, it delivers outstanding dark room performance, thanks to the perfect inky blacks and perfect black uniformity. It has an outstanding response time, delivering clear motion with no blur trail, but this does cause stutter when watching movies. This TV also supports HDMI 2.1 on all four ports, and even though there aren't many HDMI 2.1 sources available, it could help make your TV future-proof.
Unfortunately, like all OLED TVs, there's a possibility of experiencing permanent burn-in, and the brightness of the screen changes depending on the content (ABL), which may bother some people.
The LG C9 OLED is an outstanding TV for most uses. The OLED panel produces excellent picture quality for most uses, with perfect blacks and wide viewing angles. It has a nearly instantaneous response time, which is important for gaming or use as a PC monitor. Unfortunately, there's a risk of burn-in, and the brightness of the screen changes with different content, which may be distracting.
The LG C9 is an outstanding TV for watching movies. With OLED's ability to turn individual pixels off, you get perfect blacks when watching in the dark. This emissive technology also allows the TV to display bright objects in dark scenes with no blooming at all. Its near-instantaneous response time results in fast scenes that look clear and almost blur-free; however, it may also cause lower frame rate content to appear stuttery.
The LG OLED C9 is an excellent TV for watching TV shows during the day. It has good peak brightness and an impressive anti-reflective coating, so you shouldn't have any issues, even in a bright room. It also has wide viewing angles, which is great if you like to walk around with the TV on.
The LG C9 is an excellent TV for watching sports. Its extremely fast response time delivers an image with almost no motion blur, and there's very little dirty screen effect that can be distracting. Its wide viewing angles are perfect for watching a game with a big group of friends, and lower resolution content like cable sports are upscaled well, without any visible artifacts.
The LG C9 is an exceptional TV for gaming. It has a remarkably low input lag and near-instantaneous response time, so fast-paced games look crisp, with almost no motion blur. It supports variable refresh rate to reduce screen tearing, and it has been certified to work with recent NVIDIA graphics cards. When gaming on a compatible console like the Xbox One, its 'Auto Low Latency Mode' saves you the trouble of having to switch picture mode.
The LG OLED C9 is an excellent TV for watching movies in HDR. The OLED panel produces perfect blacks, it has a wide color gamut, and good peak brightness in HDR. Unfortunately, the TV's automatic brightness limiter (ABL) causes the brightness to fluctuate with different content, which may bother some people.
Excellent TV for gaming in HDR. It has excellent gaming performance, thanks to the nearly instantaneous response time and low input lag. It has an excellent wide color gamut and good peak brightness in HDR. The brightness changes with different content, though, and this might bother some people, especially with bright games. There's also a possibility of burn-in, which might be an issue due to the static elements found in most games.
The LG OLED C9 is an excellent TV to use as a monitor, as it has an excellent low input lag and outstanding response time, making your desktop experience feel responsive. However, care should be taken to avoid static user interface elements being displayed for a long time, as there's a risk of permanent burn-in. The TV can also display chroma 4:4:4 properly and it has wide viewing angles, so the image remains accurate even if you sit up close.
We tested the 55" C9 (OLED55C9PUA), and we expect our results to be valid for the 65" (LG OLED65C9PUA), and the 77" (LG OLED77C9PUA) models as well.
If someone comes across a different type of panel or if their LG C9 doesn't correspond to our review, let us know and we will update the review. Note that some tests such as the gray uniformity may vary between individual units.
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The LG C9 we tested was manufactured in March 2019; you can see the label here.
All in all, the LG C1 OLED is a step up from the LG C9 OLED. Because most OLED panels perform similarly, you can't really go wrong with the C9, but in the years since its release, LG has improved upon certain things that are apparent with C1, despite the fact that our unit falls short in certain areas like color accuracy and brightness due to panel variation. Most notably, gaming performance is improved on the C1, including better VRR with a wider range, more BFI options, and lower input lag. Still, if you can find the C9, it still offers amazing value.
The LG CX OLED and its predecessor, the LG C9 OLED, are two very similar-performing TVs. The C9 has better gray uniformity and viewing angles, but that could be due to panel differences. The CX has better built-in speakers and the black frame insertion works at 120Hz, but it causes some duplication in motion. Overall, they're two excellent TVs that should please most people.
The Samsung Q90/Q90R and the LG C9 use different panel types, each with their advantages and disadvantages. The C9 looks much better in a dark room, as the OLED panel delivers a nearly infinite contrast ratio and near-perfect black uniformity. The Q90R is significantly brighter, and the brightness doesn't change as much with different content (ABL). The C9 has better gray uniformity and better viewing angles. The C9 has a risk of permanent burn-in when exposed to static content, but the Q90 doesn't.
Although they deliver very similar picture quality overall, the LG G2 OLED is a bit better than the LG C9 OLED. The G2 is a lot brighter, especially with HDR content, so really bright highlights in some scenes stand out better. On the other hand, the C9 is a bit more versatile, as it includes a stand, whereas the G2 is designed to be wall-mounted and doesn't come with a stand.
The LG C9 OLED is a bit better than the LG C7 OLED. The two TVs were tested under different test benches, but some comparisons can still be made. The C9 has wider viewing angles and lower input lag, and is more future-proof thanks to its input ports. The C9 has 4 HDMI 2.1 inputs, which for the moment doesn't add much if anything at all. When HDMI 2.1 sources become available, the C9 should support a 4k @ 120Hz input, even at full chroma. The C9 also supports eARC and supports the HDMI 2.1 variable refresh rate technology, which is currently only supported by the Xbox One.
The LG C9 and LG C8 OLED are extremely similar overall. The C9 we tested had less temporary image retention, but this varies between units, and might not be indicative of the full lineup. The biggest difference between these TVs is the inputs. The C9 has 4 HDMI 2.1 inputs, which for the moment, doesn't add much if anything at all. Once there are HDMI 2.1 sources, the C9 should support a 4k @ 120 Hz input, even at full chroma. The C9 also supports eARC and supports the HDMI 2.1 variable refresh rate technology, which is currently only supported by the Xbox One.
The LG C9 OLED and the LG GX OLED are two similar TVs with different designs. The GX is meant to be wall-mounted and comes with a dedicated wall-mount instead of a stand. It also has a wider VRR range, a Black Frame Insertion feature that flickers at 120Hz, and better speakers. On the other hand, the C9 comes with a stand and has better out-of-the-box color accuracy, but this may vary between units.
The LG B8 OLED and the LG C9 OLED deliver very similar picture quality overall. The C9 supports some great new features, including HDMI 2.1, eARC, and HDMI Forum's variable refresh rate technology. Although all of these features don't add much now, they do make the C9 a slightly more future-proof choice.
Overall, the LG C9 OLED is better than the Samsung Q90T QLED. Due to OLED's emissive technology, the LG can produce perfect blacks. The LG also has better uniformity, faster response time, and it supports NVIDIA's G-SYNC to reduce screen tearing when gaming. However, the Samsung can get much brighter, it has lower input lag, and there's no risk of permanent burn-in.
The LG C9 OLED is slightly better than the Sony A9G. The LG has a lower input lag, which is great for gamers, and supports HDMI Forum VRR for nearly tear-free gaming. The C9 can also get brighter in SDR which, however, isn't that noticeable and could be due to panel variance.
The LG C9 OLED is a much better TV than the Sony X950H. The LG is an OLED that can produce perfect blacks with its infinite contrast ratio, and its response time is much faster, which results in less motion blur. Also, the LG has lower input lag and it supports VRR to reduce screen tearing when gaming. The Sony has better color accuracy, though, and it can get a lot brighter to make highlights pop in HDR content.
The LG C9 OLED is better overall than the Samsung Q80/Q80T QLED. Thanks to its OLED panel, the LG produces perfect blacks, resulting in an unparalleled viewing experience for movies, especially in HDR. The viewing angles on the LG are also much better, and it has a near-instantaneous response time, resulting in clear motion. On the other hand, the Samsung has more accurate colors out-of-the-box and can get brighter. The Samsung also uses an LCD panel that doesn't suffer the risk of permanent burn-in, like the OLED. It's worth noting, though, that this likely won't be an issue for most OLED owners who watch varied content.
The LG C9 OLED is a bit better than the Sony A8G. The C9 supports many new technologies, including HDMI 2.1 on all four HDMI ports, as well as eARC, and HDMI Forum's new variable refresh rate technology, great for Xbox One gamers. The C9 also has significantly less input lag, which is great for gaming or use as a PC monitor.
The Sony A9F OLED and the LG C9 are both OLED TVs, and they perform almost identically. The LG C9 is a bit brighter and has slightly less input lag. Although the Sony A9F supports eARC, the LG C9 supports the extra bandwidth of HDMI 2.1 on all four HDMI inputs. Although this doesn't add anything at the moment, once there are HDMI 2.1 sources on the market, this should allow the C9 to accept a 4k @ 120Hz signal, even with a 10 bit, full chroma signal.
These are two different types of TVs, each with advantages and disadvantages. The LG C9 OLED is an OLED TV that delivers an outstanding dark room performance thanks to its perfect blacks. The LG has wider viewing angles and delivers very crisp motion, thanks to the nearly instantaneous response time. The Samsung Q70/Q70R QLED has a VA panel that doesn't have the burn-in risk that comes with OLED technology and is more suitable for a bright room as it can get brighter overall. The Samsung has a low input lag with motion interpolation, which is great for gaming.
The Samsung Q900/Q900R 8k QLED and the LG C9 OLED are two different types of TVs, each with advantages and disadvantages. The LG has better dark room performance due to the perfect blacks of its OLED panel. The LG also has wider viewing angles, which is great if you have a large room. The Samsung, on the other hand, has an 8k resolution, can get significantly brighter (which is great for a bright room), and doesn't have the risk of permanent burn-in.
These are two different types of TVs, each with its advantages and disadvantages. The LG C9 is an OLED TV that delivers an outstanding dark room performance thanks to its perfect blacks. The C9 has wider viewing angles and delivers motion with almost no blur, thanks to the nearly instantaneous response time. The Samsung Q80R doesn't have the burn-in risk of the OLEDs and can get brighter, which is great for a bright room. Finally, the Samsung Q80R has low input lag with motion interpolation.
The LG C9 and the Sony A8F OLED are both OLED TVs and perform very similarly, but the C9 is slightly better overall. The C9 has lower input lag, great for gamers or use as a PC monitor. The C9 also supports some newer technologies, including HDMI 2.1 on all four inputs, eARC, and the HDMI 2.1 variable refresh rate technology. Although some of these features don't add much for now, as there are no sources available, it does make the C9 a more future-proof choice.
The Samsung Q9FN/Q9/Q9F QLED 2018 and the LG C9 OLED use different panel types, each with their advantages and disadvantages. The C9 looks much better in a dark room, as it can deliver perfect blacks and perfect black uniformity thanks to the OLED panel. The Samsung is significantly brighter, suitable for any room, and doesn't have the burn-in risk. The C9, on the other hand, has better gray uniformity and much wider viewing angles. It's also more future-proof, thanks to its HDMI port.
The LG C9 OLED is a much better TV than the Samsung Q60/Q60R QLED. The LG looks much more premium, can get brighter for HDR content, has much better gray and black uniformity, has a wider color gamut, and does a better job at handling reflections. On the other hand, the Q60 has more accurate colors out-of-the-box, and doesn't run the risk of permanent burn-in if displaying static content for extend periods of time.
The Sony X900F and the LG C9 OLED use different panel types, each with their strengths and weaknesses. The C9 delivers an amazing dark room performance and has a nearly instantaneous response time, which results in extremely clear motion. Unfortunately, it also runs the risk of permanent burn-in, which the Sony X900F is immune to. The X900F can get a lot brighter and can easily fight glare if you'll be watching TV in a bright room.
The Sony Z9F and LG C9 use different panel technologies, each with their advantages and disadvantages. The Z9F uses a VA panel and is much brighter than the C9, and the brightness doesn't change as much with different content (ABL). The C9 looks much better in a dark room, as the OLED panel delivers near-perfect black uniformity and an infinite contrast ratio. The C9 has a nearly instantaneous response time, but this results in more noticeable stutter when watching movies. The C9 also has a chance of permanent burn-in when exposed to static content, but the Z9F is immune to burn-in.
The LG C9 and the Vizio P Series Quantum X use different panel types, each with their strengths and weaknesses. The C9 is better for a dark room, and it has incredibly wide viewing angles. The C9 also has a nearly-instantaneous response time, outstanding low input lag, and some great future-proof features, like 4 HDMI 2.1 ports. As an OLED TV, the C9 does have a risk of permanent burn-in. The Quantum X, on the other hand, is much brighter, and small highlights in HDR movies look much closer to what the director intended. There is also no chance of burn-in with the Quantum X.
The Sony X950G and the LG C9 use different panel types, each with their strengths and weaknesses. The C9 delivers the best dark room performance and has a nearly instantaneous response time, which results in extremely clear motion. Unfortunately, this also comes with a risk of permanent burn-in, which the Sony X950G is immune to. The X950G can get a lot brighter than the C9, especially when displaying large, bright scenes.
The LG E8 and C9 deliver very similar picture quality, thanks to their impressive OLED panels. The C9 is slightly better, though, especially as a future-proof model. The C9 supports HDMI 2.1 on all HDMI ports and supports many new features, including HDMI Forum's variable refresh rate technology, as well as eARC.
The LG C9 OLED is a much better TV overall than the LG SM9000. The OLED looks more premium, has perfect blacks thanks to its individually backlit pixels, a higher peak brightness, much better gray and black uniformity, better viewing angles, better reflection handling, more accurate colors out-of-the-box, a wider color gamut, and much better motion handling. On the other hand, the SM9000 is an LED TV that doesn't suffer the risk of permanent burn-in when watching a lot of static content like the OLED does, though we don't expect this to be an issue for the majority of people.
The LG C9 is a high end 2019 OLED TV, and directly replaces LG's 2018 C8. All OLEDs deliver very similar overall picture quality, so the main differences between this TV and its competitors are the additional features and the design. The main competitors to this TV are the LG B9, LG E9, Sony A9G, and Sony A8G. The main LED competitors are the Sony Z9F and the Samsung Q90R.
The design of the 2019 LG OLED C9 is excellent. Overall, it's very similar to the 2018 LG C8, with only minor differences. The stand supports the TV well, and there's very little wobble. The stand itself is slightly different; it isn't as tall as the C8's, so the panel is closer to the table, and the front portion of the stand doesn't stick out as much. The TV is well-built, so there shouldn't be any issues using it, but it's thin, so care should be taken when moving it.
The stand is very wide and will require a fairly large table. It supports the TV well, though there's still a bit of wobble when nudged.
Footprint of the 55" TV stand: 35.6" x 9.75".
The back of the TV is nearly identical to the 2018 LG C8. There are back facing inputs as well as side-facing ones. There's a removable plastic cover, which hides the built-in cable management.
The borders are extremely thin. There's almost no gap between the edge of the bezel and the start of the pixels.
Since all the electronics are housed in the bottom portion of the TV, the top half is much thinner, but also more fragile, as it can flex easily. The TV can be wall-mounted and shouldn't stick out much unless you use the back-facing ports.
Build quality is excellent. The panel-only portion of the TV can flex a bit, but we don't expect this to cause any issues. It's very similar to the 2018 C8 and B8.
This TV has an infinite contrast ratio, as its emissive technology allows it to turn pixels off individually. This results in perfect blacks when viewed in the dark.
This TV doesn't have a local dimming feature since it doesn't have backlights. OLEDs can dim pixels individually, so bright objects and subtitles are displayed perfectly, without any blooming or brightness changes.
Update 06/06/2019: We've retested the SDR peak brightness of the LG C9 with the firmware update 03.60.02. There are no significant changes in brightness from our previous measurements.
The LG C9 OLED has good peak brightness with SDR content. Small highlights are brighter than on the C8 or B8, but this results in a more aggressive Automatic Brightness Limiter (ABL), which dims the screen significantly when larger areas of the screen get bright.
The LG C9 has a new Peak Brightness setting, which adjusts how the ABL performs. Setting this to 'Off' results in most scenes being displayed at around 303 cd/m², unless the entire screen is bright, in which case the luminosity drops to around 139 cd/m². Increasing this setting to 'Low', 'Med', or 'High' increases the peak brightness of small highlights. If ABL bothers you, setting the contrast to '80' and setting Peak Brightness to 'Off' essentially disables ABL, but the peak brightness is quite a bit lower (246-258 cd/m² in all scenes).
These measurements were taken in the 'Expert (Dark Room)' Picture Mode, with OLED Light set to '100', Contrast set to '90', Peak Brightness on 'High'.
The LG C9 has very good HDR peak brightness.There's quite a bit of variation in brightness when displaying different content, mainly due to the aggressive ABL. This is especially noticeable in content with large bright areas.
The HDR brightness measurements were taken in 'Cinema' mode, with OLED Light set to '100,' and Peak Brightness on 'High.' Different picture modes and color temperatures will produce different results.
Excellent gray uniformity. There's very little dirty screen effect, which is great for sports fans. Uniformity of near-dark scenes is even better, which is great. Like previous OLED TVs, there are some very faint horizontal and vertical lines noticeable in a pitch-black room when displaying near-black scenes.
The LG C9 has excellent wide viewing angles. Brightness and black levels remain good even at extreme viewing angles, but colors begin to shift at moderate angles.
Since OLEDs can turn pixels off completely, black uniformity is virtually perfect, which is great for watching in a dark environment.
Reflection handling is outstanding. Its anti-reflective coating has a slight purple tint, though it's common among high-end TVs. You shouldn't have any issues in most well-lit rooms, but the TV's brightness may not be able to overcome glare if the TV is placed opposite a window.
Before calibration, the LG C9 has good color accuracy. There are some inaccuracies with a few colors, though they're hard to notice. However, pure whites have a yellowish tint.
Overall, it follows the gamma target well, but some near-black details are crushed. This can be seen in the spike at the beginning of this higher resolution gamma plot. Increasing the Brightness setting does help compensate for this a bit, but doesn't completely correct it.
If you want a TV with better out-of-the-box color accuracy, check out the Sony A8H OLED.
After calibration, this TV has nearly perfect accuracy. The white balance dE and color accuracy are both extremely good, and any remaining inaccuracies are completely unnoticeable.
The TV features an auto-calibration feature. This feature still requires a licensed copy of CalMAN, and a colorimeter.
You can see our recommended settings here.
This TV upscales 480p content well, with no obvious upscaling artifacts.
Although this TV uses an RGBW pixel structure, there are no issues displaying 4k content, as each pixel has all four sub-pixels.
Like all other OLEDs, the LG C9 uses 4 sub-pixels, but all 4 are never used at the same time. This image shows the red, white, and blue sub-pixels. You can see the green sub-pixel in our alternative pixel photo.
The LG C9 can display a wide color gamut, which is great for watching HDR content. It can display almost the entire DCI P3 color space and has good coverage of the wider Rec. 2020 color space.
In 'Cinema' mode, the TV follows the target PQ curve very closely but has a sharp roll-off at the TV's peak brightness, so some bright detail may be crushed. In 'Game' mode, the EOTF is nearly identical.
With the 2019 version of the CalMAN software, it's possible to customize the TV's EOTF. We didn't test this out, but you can find out more about this feature here.
If you find HDR too dim, check out our recommendations here.
This TV has decent color volume, very similar to the C8. Although it has an excellent color gamut, it loses volume at the top. The WRGB pixel structure allows it to produce bright whites, but colors aren't as bright. On the other hand, thanks to the perfect contrast ratio it can produce dark saturated colors with no issues, unlike the majority of LED TVs.
The LG C9 has excellent gradient handling. There's some very slight banding in some colors, but this shouldn't be very noticeable.
When watching lower-quality content that has lots of banding in it, the Smooth Gradation feature can help to reduce banding, especially when there are large areas of banding. Note that enabling this feature can cause a loss of fine details in some scenes, but it appears to behave differently from the C8 and is a bit more conservative.
The LG C9 shows some slight signs of temporary image retention, but it's too faint to be detected by our software.
This test is only indicative of short term image retention, and not the permanent burn-in that may occur with longer exposure to static images. We're currently running a long-term test to help us better understand permanent burn-in. You can see our results and read more about our investigation here.
Update 11/01/2019: Updated text to include our stance on burn-in.
Although we don't expect most people who watch varied content to have any issues, OLED TVs, such as the LG OLED C9 do have the possibility of experiencing burn in.
This TV has three features to help mitigate burn-in. We recommend enabling the Screen Shift option, and setting Logo Luminance Adjustment to 'Low.' There's also an automatic pixel refresher that can be run manually if needed.
You can read about our investigation into this here.
Like all OLED TVs, the LG C9 has a nearly-instantaneous response time. There's some very subtle overshoot in near-black scenes, but this shouldn't be very noticeable.
This extremely fast response time can cause the image to stutter, which may bother some people.
Update 06/25/2020: We incorrectly stated that this TV was flicker-free, it's not. Although the flicker isn't at all noticeable, there is a slight dip in brightness every 8ms.
The LG C9 doesn't use PWM, as there's no backlight, but there's a slight dip in brightness approximately every 8 ms, which coincides with the TV's refresh rate. This shouldn't be noticeable.
The LG OLED C9 has an optional Black Frame Insertion feature that can improve the appearance of motion.
This option is activated by setting TruMotion to 'User' and toggling the OLED Motion setting. This option can only be turned on or off, and it always flickers at 60Hz. Enabling this option will cause judder when playing back 24p content.
Update 09/16/2019: We've retested this TV with the same video that we tested the LG C9 and LG E9 OLED and found its interpolation behavior to be the same. The text below has been updated.
This TV can interpolate lower frame-rate content up to 120Hz. This introduces an effect known as the 'Soap Opera Effect,' which some people don't like, but reduces the amount of stutter. The C9, unlike many new TVs, continues to interpolate during fast scene changes, which can create a lot of artifacts. This behavior is similar to the B9 and the E9.
See here for the settings that control the C9's motion interpolation feature.
Due to the nearly instantaneous response time, 24p motion can appear to stutter, as each frame is held static onscreen for nearly the entire time. This can be especially noticeable in slow panning shots when watching movies.
If this effect bothers you, you can either enable the TV's OLED Motion feature, which can help a bit, or enable the LG C9's motion interpolation feature.
The LG C9 is able to play 24p content without judder, regardless of the source.
See our recommended settings to remove judder here.
When the TV's BFI mode is enabled, there's always judder with 24p content.
Update 07/03/2020: We previously reported that the LG C9 has a VRR minimum of <20Hz. We've retested it and can confirm that the VRR minimum is <40Hz.
Update 11/27/2019: The LG C9 is now compatible with recent NVIDIA G-SYNC graphics cards, and is officially certified as G-SYNC compatible.
Update 12/12/2019: We retested the LG C9 with the latest firmware, and it no longer flickers when in Game Mode on an Xbox One with HDR and the variable refresh rate feature enabled.
The LG C9 has a native 120Hz refresh rate, and it supports VRR, which is great. It only supports HDMI Forum's new HDMI-VRR format, which is only supported on new Xbox Ones, or with a recent NVIDIA graphics card. The LG C9 is officially supported by NVIDIA's G-SYNC compatible mode, which is enabled automatically when connected to a recent NVIDIA graphics card.
Update 05/02/2019: We've retested the input lag of the LG C9 with the firmware update 03.50.31. The input lag measurements in SDR game and PC modes have decreased.
Update 05/09/2019: Text clarifications added.
Update 05/17/2019: We've retested the input lag on the same firmware (03.50.31) and found the 4k @ 60Hz + HDR input lag is in the same ballpark as the other resolutions (around 13ms). We don't know why our previous measurements were higher, as we did confirm them twice. We've also updated the 1440p @ 60Hz input lag with this latest firmware.
Update 06/01/2020: We've retested the input lag with G-SYNC enabled using the latest firmware (04.70.05) and the score has been adjusted accordingly. Unfortunately, we were still unable to get a 4k @ 120Hz signal, as we needed a HDMI 2.1 source, and we can't retest the TV since we've sold it. The tests were performed on a PC equipped with an NVIDIA RTX 2070 graphics card.
The LG C9 has outstanding low SDR input lag in 'Game' mode. In 'PC' mode, the input lag is higher than the C8, which is somewhat strange. With the latest firmware (05.30.31) we measured a higher input lag with 4k @ 60Hz + HDR signals. This is fine for most people, but may be disappointing for fast-paced HDR games. This is strange, and we expect it to be reduced in a future firmware update. New on the LG C9 is support for Auto Low Latency Mode.
The LG C9 can display most common resolutions. To display chroma 4:4:4 properly, the input label must be set to 'PC', and for high bandwidth resolutions like 4k @60Hz + HDR, the HDMI ULTRA HD Deep Color setting must be enabled for the port in use.
Note: we expect this TV to support a 4k @ 120Hz input, and other owners have reported that it does. Unfortunately, it requires an HDMI 2.1 input, and none were available while we still had this TV. We don't have it anymore, so we're unable to retest the TV and update the review.
This TV is advertised to support HDMI 2.1, but there weren't any HDMI 2.1 sources when we tested it. We can't test it with an HDMI 2.1 source because we've since sold the TV.
The LG C9 supports eARC when connected to a compatible AV Receiver, which allows it to send higher quality DTS:X and Dolby Atmos via TrueHD sound from an external device to your receiver. Like the 2018 LG OLEDs, it also supports DTS and Dolby Digital passthrough to a standard ARC receiver.
When connected to a PC, the PC detected the C9 as a stereo device, so it wasn't possible to send 5.1 or 7.1 audio to the TV without bypassing the PC's autodetection system.
Update 05/24/2019: Retested the eARC passthrough with a different PC, and no bypassing was necessary: the PC still detected the C9 as a stereo device, but the bitstreaming ignored that fact and sent 7.1 TrueHD audio without a problem.
The LG OLED C9 has a decent frequency response. The low-frequency extension (LFE) is at 67Hz, which is decent, but slightly worse than the C8. This results in a bass that isn't able to produce much thump or rumble but has a decent amount of punch and body. The frequency response above the TV's LFE is well-balanced, which is important for clear dialogue. It can also get pretty loud, without too much pumping and compression artifacts under maximum load.
Mediocre distortion performance. There's a much higher amount of THD at max volume, but at 80dB it's more reasonable.
Its successor, the LG CX OLED, has better overall speakers.
LG's WebOS has a clean and user-friendly interface. There aren't any serious issues with its performance, but some apps do hang a bit when launching them. It now includes a Home Dashboard, which is very similar to Samsung's Smart Things system.
Although we weren't able to take a picture of them, we did see ads during our testing, similar to the ads we saw on last year's SK8000. We were able to remove some of them by disabling the Home Promotion setting, but as ads aren't always visible, we aren't certain if it's possible to entirely remove them.
The LG Content Store has a vast selection of apps available. If there's a specific app you want us to check for, let us know in the discussions down below. With a recent firmware update, there's now support for Apple HomeKit and AirPlay 2.
The LG C9 also supports WiSA wireless speaker technology, although we didn't test this.
The LG C9 comes with LG's magic remote, which can be used like a regular remote or as a mouse pointer. It can be programmed to work other devices, even if the devices don't support CEC. There are shortcuts for the most popular streaming apps, like Netflix and Prime Videos, and it has a built-in microphone for voice control. You can use your voice to control the TV, launch apps, or ask general questions like the weather and time.
There's a single button located at the center, beneath the screen. It allows you to turn the TV On/Off, change inputs, volume, and channels. The picture was taken with the stand removed.