Settings for LG CX to get most out of 2021 ATV and HDMI 2.1 certified cable?

[kofman13]

Just got new 2021 Apple TV(with hdmi 2.1) and a Zeskit HDMI certified 48gbps hdmi 4:4:4 cable, what settings do I need to adjust or enable on my LG CX for that HDMI port to get the most possible quality out of the new ATV? (I never had an external device and cable capable of these more pro features)

 

[JohnnieBBadde]

Currently doesn't matter at all since the ATV 4K 2021 does not use HDMI 2.1 features for its video output. The only active HDMI 2.1 feature is eARC, used to receive audio from the dedicated TV so that the ATV is then able to send it out via AirPlay et al.

- Best settings with HDR: 4K/60 Hz/YCbCr 4:2:2 (worse colors but with HDR)
- Best settings without HDR: 4K/60 Hz/RGB High (better colors but no HDR)

 

[kofman13]

Currently doesn't matter at all since the ATV 4K 2021 does not use HDMI 2.1 features for its video output. The only active HDMI 2.1 feature is eARC, used to receive audio from the dedicated TV so that the ATV is able to send it out via AirPlay et al.

- Best settings with HDR: 4K/60 Hz/YCbCr 4:2:2 (worse colors but with HDR)
- Best settings without HDR: 4K/60 Hz/RGB High (better colors but no HDR)

Is the difference between the two color modes very noticeable? Will test when I get home

 

[JohnnieBBadde]

Is the difference between the two color modes very noticeable? Will test when I get home

Testing yourself and not blindly following others' statements is always good.

- If you use your ATV for the consumption of video only then you will not notice a difference since the video files themselves that are being sent out from all (?) streaming services are currently encoded with the limited YCbCr color space.

- If you use your ATV for intensive photo viewing then the differences will be more noticeable depending on the kind of photos you're looking at.

- To not strain your OLED TV with "fake always-on HDR" created by the ATV's graphical user interface I'd personally set the HDMI output to SDR but enable frame rate (= HDMI signal's Hz change) and dynamic range (= switching between SDR and HDR) content matching, then if a video app is actually sending out real HDR content for the ATV to output via HDMI, the LG CX will change to HDR mode. Note: The YouTube tvOS app is currently broken, the best your ATV can get from there is 4K/60 FPS/SDR at the moment.

 

[AL2TEACH]

Just got new 2021 Apple TV(with hdmi 2.1) and a Zeskit HDMI certified 48gbps hdmi 4:4:4 cable, what settings do I need to adjust or enable on my LG CX for that HDMI port to get the most possible quality out of the new ATV? (I never had an external device and cable capable of these more pro features)

1. Heading to All Settings -> Connection -> Device Connection Settings
2. Change your Sound Out to HDMI ARC
3. Go to All Settings -> Sound -> Additional Settings and turn on eARC.
4. Under All Settings -> Sound -> Additional Settings -> Digital Sound Out select “Pass Through” and what JohnnieBBadde stated about setting to 4k SDR. For YouTube, I use the tv's app.
5. what's your audio setup because that's where earc shines and if it's just video no need to worry about earc.

 

[garethjs]

Same TV with the new apple tv 4k connected to homepods stereo pair and settings identical to above.

With digital soundest set to pass through, I have issues with the music app playing music videos. Each time I scroll though a video and it goes full screen and into thumbnail the music stops and the timeline scrubs back and forward before it starts playing. Most irritating. Its like its trying to re-sync the audio

If I set it to "auto" then each time the video goes full screen and thumbnail the music stops but continues the sec the image returns. However it doesn't have to scrub back or forward and re-sync the audio so this is the only workable solution for now.

If I disable eARC all together and watch music videos, there is no disruption of sound despite the screen going black whilst the video clip goes full screen and thumbnail (im assuming the split second black screen is the TV switching frame rates of the video clip and that of my OS since I have match frame rate on)

Not sure who is at fault here. LG or apple. Also no idea why eARC setting should affect what Im watching on the appleTV that is connected to the homepods itself

 

[w5jck]

Just got new 2021 Apple TV(with hdmi 2.1) and a Zeskit HDMI certified 48gbps hdmi 4:4:4 cable, what settings do I need to adjust or enable on my LG CX for that HDMI port to get the most possible quality out of the new ATV? (I never had an external device and cable capable of these more pro features)

Here are the basic settings I use with my 1st gen ATV 4K:

ATV 4K Video Settings

• Format: 4K SDR
• HDMI Output: YCbCr
• Chroma: 4:4:4
• Match Content: Range & Frame Rate

Basically, this allows my ATV 4K to use what is being streamed as for as formatting goes. That is, it doesn't try to force HDR, or Dolby Vision, or anything else, but it will use them if they are within the streamed content. That assumes the app being used to stream plays by those rules, and not all of them do.

Don't worry too much about your TV's settings, as the ATV 4K will use and send to the TV what it, the ATV 4K, is set to use.