New Apple TV 4K

[rmilyard]

So is the new Apple TV 4K with Plex going to support Dolby Atmos playback yet?

I have last version and never got working so use my Shield.

[tom80H]

Seems to be working but could depend on the Apple TV’s audio configuration (e.g. allowing it to actually pass audio through vs. encoding it as AC3).

Here’s a link from ~1 year ago where users discussed that.

Apple TV 4K -> EAC3 not sending atmos

I’ve been reading through the various threads on plex/atv 4k playing lossy atmos. I’ve got a file that has EAC3 5.1 w/ DDP. However, when playing it, my Denon shows it as PCM. I expected it to show up as Atmos on the receiver - which is how it shows up when playing Netflix via the ATV. I checked the transcoding and it looks like it is getting sent over directly. Has anyone gotten plex and ATV to play dolby digital plus via EAC3? [plex]

[Juventino]

This is something I’m curious about

[dent_1]

Well, i have been using the shield 2015 for a while since trueHD sound does not go well with the current apple TV. Hopefully the new one can play it without transcoding. I like the shield, but it’s sluggish and bad UI compared to apple tv. I hope someone can post their results later in may.

[blackzwe]

For me Atmos only works with legacy player on Plex i.e. with “Use Old Player” set to On, have a lot of Dolby Atmos and Vision content and its a bit of a mess trying to play it with Plex, for now I’m on Infuse until the Dolby Vision issue is sorted out. Would move to N.Shield, but have a lot of iTunes content, until Apple gets Apple TV on android with all its bells and whistles not worth the move.

[Scott-M]

The Specs for the updated Apple TV 4K are available, and it does not support TrueHD audio

Apple TV 4K - Technical Specifications

Let’s clarify these topics:

Dolby Atmos is a technology that exists in two different audio codecs:

• TrueHD
• E-AC3

The Apple TV 4K (1st and 2nd gen) supports E-AC3, but does not support TrueHD.
Any Atmos content you have that is E-AC3 will play on the Apple TV 4K.

Atmos contained in TrueHD can not play back on the AppleTV. The Atmos metadata will be lost when transcoding TrueHD to E-AC3.
Your only device options for audio passthrough support of TrueHD is a Nvidia Shield, PC, or Xbox (currently in preview)

That said, there is almost no disc based content out there that contains E-AC3 Atmos; it is all TrueHD.

As for Dolby Vision
There are currently 6 known profiles (versions) for Dolby Vision HDR.
The Apple TV 4K only supports Profile 5.
The Dolby Vision found on 4K Discs is Profile 7.

You can play any Dolby Vision content on the Apple TV 4K (using Plex or Infuse) that is Profile 5.
Your only option to play back 4K rips with Dolby Vision (Profile 7) is the Nvidia Shield.

[tyleromeo]

Thanks Scott for the details. Is it possible that Apple could allow for Dolby True HD passthrough? They are probably going to release a new TVOS at WWDC in a few months. But I’m curious how the new box does with Plex once it’s shipping. If it can’t then I’m getting a Shield since both Apple TV and PS5 with all their CPU power and HDMI 2.1 refuse to handle Dolby True HD Atmos tracks.

[Scott-M]

This has been discussed in detail over on the Infuse forums:

Help get (more) Dolby Atmos on Apple TV

As I understood it, there is no hardware limitation for supporting TrueHD, and Apple could in fact support it through a software update. But unless Apple makes that change, the most any developer could do is decode TrueHD to PCM on the box (which is what Infuse does) but that looses Atmos data in the process.

I went in to more detail on this here:

Nothing ever works as it should

Great question. Let me start with a quick high level overview: When you play a Blu-Ray with TrueHD or DTS-HD MA, the Blu-Ray player sends that format to your receiver, and the receiver decodes the audio before sending out to your speakers. LPCM is just another Lossless (HD) audio source that can be directly streamed to your receiver without decoding. Unless your TV has eARC (which is still very new), it will only be able to pass 5.1 lossy audio down to your receiver. The Apple TV supports up…

IMO it’s not so much hardware power (audio passthrough does not require any additional processing) as it is licensing and usability.
Remember these set-top boxes are streaming boxes. TrueHD has a much larger bitrate, and would require more bandwidth from your internet. So it’s a safer solution to support the lossy codecs with smaller bitrates like E-AC3. In the overall consumer space users like us that would benefit from TrueHD and Profile 7 DV are a small percentage of their overall user base.

[blackzwe]

Couldn’t have explained it better @Scott-M. Just in case y’all hadn’t noticed, currently Dolby Vision playback is buggy on ATV, but we understand a fix is on the way…

Plex displays wrong colours with Dolby Vision on AppleTV 4k

With the Infuse client on the same aTV Dolby Vision works with proper colours. Seems to be the aTV Plex Client.

Follow this thread for the updates.

[tyleromeo]

Thanks Scott. I totally hear you. Most people are not interested in playing back 50GB 4K files from their personal servers. They want the simple option to choose a streaming service and hit play and forget about any tech specs or details. Lets hope Apple can at least “unlock” the potential of this new box with new software this June, so the little guys can also enjoy their box to its full potential.

[thecodingart]

For the following statement:

Atmos contained in TrueHD can not play back on the AppleTV. The Atmos metadata will be lost when transcoding TrueHD to E-AC3.

Does this have to be true? Could Plex transcoders keep the Atmos metadata as a proper Atmos enabled E-AC3 Atmos encoded streaming audio profile? Not to say it’s a “wonderful” solution to a problem caused by Apple, but it could be a solution if possible.

This is following off of this comment of course:

The Apple TV 4K (1st and 2nd gen) supports E-AC3, but does not support TrueHD.
Any Atmos content you have that is E-AC3 will play on the Apple TV 4K.

I also jumped in here to see if there were any benefits to using Infuse over the Plex client with any “trickery” that may enable higher quality audio pass through to my receiver (specifically for Atmos and DTS-X).

[Scott-M]

There is currently no process to convert TrueHD Atmos to EAC-3 Atmos on the fly. Dolby has a tool to do this conversion offline, but it is very expensive.
https://developer.dolby.com/forms/dolby-atmos-conversion-tool/

Currently, your only option would be to use the tool from Dolby and prep your media beforehand.

@thecodingart

I also jumped in here to see if there were any benefits to using Infuse over the Plex client with any “trickery” that may enable higher quality audio pass through to my receiver (specifically for Atmos and DTS-X).

See my answer in the forum post I linked to above

Nothing ever works as it should

Great question. Let me start with a quick high level overview: When you play a Blu-Ray with TrueHD or DTS-HD MA, the Blu-Ray player sends that format to your receiver, and the receiver decodes the audio before sending out to your speakers. LPCM is just another Lossless (HD) audio source that can be directly streamed to your receiver without decoding. Unless your TV has eARC (which is still very new), it will only be able to pass 5.1 lossy audio down to your receiver. The Apple TV supports up…

[thecodingart]

Ah, that’s exactly what I was looking for (not being a specialist in this exact area I wasn’t sure). Thanks for the update and it is totally a bit of a shame. I imagine the next ideal step (again, quick rabbit hole) would be to automate conversations on a library ahead of playback like you mentioned (which is looks like this toolset is GUI driven… not even sure if something is available terminal wise). Again, not ideal. Fingers crossed for tvOS 15.

[Scott-M]

I would also take a serious look at how important using an Apple TV (for Plex) is to your solution.

It’s is no question there is a quality loss between TrueHD and EAC-3.
Is it worth the hours of converting to retain Atmos (at a now reduced quality) to continue using an Apple TV for Plex? As opposed to getting an Nvidia Shield that supports TrueHD and DTS-HD MA passthrough out of the box.

And this is still all theoretical, afaik nobody in the community has actually done it before. And that tool from Dolby relies on you having the source audio, and is not publicly available (the tool or the source audio)

I personally have an Nvidia Shield just for Plex playback, and use an Apple TV 4K for everything else (my wife still uses the ATV for Plex)

[thecodingart]

Yeah, ultimately IMO (and in performance tests) tvOS is better in every way… other than this. What it really boils down to is I’m not found of migrating away from the tvOS environment just for Plex (and reality just for Object spacial sound audio). But it has become a temptation for this single one use case. If tvOS 15 removes this issue through software and I took the plunge to a Shield, I would 100% regret the purchase as the point becomes mute. I, personally avoid Android TV like the plague for various reasons, so it takes a strong and long lived argument to drive that product into my lane. (and I’m very aware of how many people are satisfied with the Shield overall).

[Scott-M]

I agree with that. Not a fan of Android TV.
And to be clear, I am 100% on board with petitioning Apple to support TrueHD and DTS-HD MA passthrough (I have already submitted feature requests through their developer portal)

I just don’t like the idea of reducing the quality of my media to cater to a specific device for a potentially limited period of time.
In the end, the media is what I care about, and the Shield allows me to not make any compromises with that media (it supports all the audio, and now Dolby Vision rips from UHD Blu-Rays)

[Scott-M]

But for the meantime, I recommend using Infuse for the best playback experience on Apple TV

[thecodingart]

Yeah, and you are driving right to home with the conundrum I’m in. I’m currently attempting to use DTS - Neural X as a compensation mechanism :(.

[Terminator2050]

If new ATV doesn’t allow audio pass through or wont allow it then - can someone explain why they have added HDMI 2.1 .

Will new ATV have eARC?

[Volts]

There’s some evidence of eARC support.

https://thetapedrive.com/the-new-2021-apple-tv-4k-2nd-gen-adds-earc-support-for-the-discontinued-homepod

Then again, that article conflates ARC and CEC, so who knows. Would Apple support something so complicated?