Apple Joining the Atmos streaming game!

[marcb]

so basically the atmos stream to the apple tv is equivalent to what an mp3 stream would be for stereo, correct?

No. It’s the equivalent of a stereo DD+ stream - which is ~2x more kbps than high quality mp3.

Edit: Do you mean in terms of the size of the entire stream? If so, I’d have to do the math, but I’d guess it’s probably somewhat comparable.

 

[marcb]

I disagree. 24/96 always sounds better to me than 24/44 no matter what the source is.

There are reasons why almost nothing is recorded professionally at 16 bits anymore. But lots of things still get recorded at 44 or 48kHz. There are reasons why editing gets done at 24 or 32 bits rather than 16 bits - and then only, if necessary, dithered down to 16 bits.

Bit depth is far more of a rate limiting factor than sample rate. If you’re trying to save on storage space, cut the sample rate, not the bit depth.

 

[pat bateman]

so basically the atmos stream to the apple tv is equivalent to what an mp3 stream would be for stereo, correct?

For dumbing down the explanation, yes. I am sure its probably more complicated than this, but if you are comparing solely bitrate, the old AC-3 standard maxed @ 640 kbps, and anecdotally AC3 sounded better than MP3 at the same bitrate. More efficient compression than MP3. E-AC-3 can now be up to 1664 kbps, but in typical streaming platforms, they are using 768 kbps, and is even more efficient than its predecessor, AC-3. So its not a quantum leap over MP3, but definitely better.

 

[SMS]

There are reasons why almost nothing is recorded professionally at 16 bits anymore. But lots of things still get recorded at 44 or 48kHz. There are reasons why editing gets done at 24 or 32 bits rather than 16 bits - and then only, if necessary, dithered down to 16 bits.

Bit depth is far more of a rate limiting factor than sample rate. If you’re trying to save on storage space, cut the sample rate, not the bit depth.

You make a good point about recording. 24 bit is necessary for the recording and production process, but not for delivery. 16 bits is more than enough for delivery to the consumer. But don't take my word for it. This is a quote from Dr Aix:

"What about 16 bit vs. 24-bit audio? It’s true that 16 bit linear PCM audio does not quite cover the entire theoretical dynamic range of the human ear in ideal conditions. Also, there are (and always will be) reasons to use more than 16 bits in recording and production.

None of that is relevant to playback; here 24-bit audio is as useless as 192kHz sampling. The good news is that at least 24-bit depth doesn’t harm fidelity. It just doesn’t help, and also wastes space.”

The full article is here.

I think that all sample rates and bit depths at CD quality or higher are capable of good sound. Compression, on the other hand, can ruin sound quality. The greater the compression, the worse the sound. A 192kbps mp3 will sound worse than a 320kbps mp3.

Atmos streams at 768kps (through Tidal and Apple). I admit I don't know the details of the compression and encoding algorithms. But it carries roughly 12 channels of audio (7.1.4), the equivalent of 6 stereo streams. 768/6=128. It seems like the equivalent compression to a 128kbps stereo stream... Which doesn't sound good. Maybe the compression algorithm is better than mp3 but I believe compression is the limiting factor in the sound quality of the current Atmos streaming services.

 

[pat bateman]

Atmos streams at 768kps (through Tidal and Apple). I admit I don't know the details of the compression and encoding algorithms. But it carries roughly 12 channels of audio (7.1.4), the equivalent of 6 stereo streams. 768/6=128. It seems like the equivalent compression to a 128kbps stereo stream... Which doesn't sound good. Maybe the compression algorithm is better than mp3 but I believe compression is the limiting factor in the sound quality of the current Atmos streaming services.

Tidal is only streaming 6 discreet channels using JOC (Joint Object Coding) AKA Atmos metadata. Basically the metadata reconstructs the original Atmos mix without having to stream additional the additional bandwidth of discrete channels. At the risk of using a broad brush, in a Atmos stream, the 2 fronts and center are 55% of the bandwidth, LFE is 5%, and the remaining 40% are the 2 rear channels. The metadata is insignificant from a bandwidth standpoint. This can of course vary by the particular mix, but this is generally the case. I can say with absolutely certainty that there is a world of difference between 768 kbps streamed Atmos and a 128 kbps MP3 according to my ears.

 

[SMS]

Tidal is only streaming 6 discreet channels using JOC (Joint Object Coding) AKA Atmos metadata. Basically the metadata reconstructs the original Atmos mix without having to stream additional the additional bandwidth of discrete channels. At the risk of using a broad brush, in a Atmos stream, the 2 fronts and center are 55% of the bandwidth, LFE is 5%, and the remaining 40% are the 2 rear channels. The metadata is insignificant from a bandwidth standpoint. This can of course vary by the particular mix, but this is generally the case. I can say with absolutely certainty that there is a world of difference between 768 kbps streamed Atmos and a 128 kbps MP3 according to my ears.

Pat, thank you for the explanation. I'll Google it, but if you happen to have a link to an explanation to how JOC works, I'd like to read about it. I'm a geeky electronic engineer, and like to understand this stuff.

If the metadata is indeed insignificant, then the bandwidth available per channel is more similar to a 320kbps mp3. That's good. It explains why I find Atmos listenable, unlike a 128kbps mp3.

I assume it is fair to say that the more active the mix is (more use of the height channels), the more bandwidth the metadata takes, and the more the front, center, and rear channels, need to be compressed (variable rate compression). Is this accurate?

My apologies that this has gotten somewhat of topic. I do find, as others have mentioned, that some lossless stereo streams have better fidelity than Atmos. I believe compression is the reason for that, and I just wish they dedicated more bandwidth to the Atmos streams.

 

[marcb]

You make a good point about recording. 24 bit is necessary for the recording and production process, but not for delivery. 16 bits is more than enough for delivery to the consumer. But don't take my word for it. This is a quote from Dr Aix:

"What about 16 bit vs. 24-bit audio? It’s true that 16 bit linear PCM audio does not quite cover the entire theoretical dynamic range of the human ear in ideal conditions. Also, there are (and always will be) reasons to use more than 16 bits in recording and production.

None of that is relevant to playback; here 24-bit audio is as useless as 192kHz sampling. The good news is that at least 24-bit depth doesn’t harm fidelity. It just doesn’t help, and also wastes space.”

The full article is here.

I think that all sample rates and bit depths at CD quality or higher are capable of good sound. Compression, on the other hand, can ruin sound quality. The greater the compression, the worse the sound. A 192kbps mp3 will sound worse than a 320kbps mp3.

Atmos streams at 768kps (through Tidal and Apple). I admit I don't know the details of the compression and encoding algorithms. But it carries roughly 12 channels of audio (7.1.4), the equivalent of 6 stereo streams. 768/6=128. It seems like the equivalent compression to a 128kbps stereo stream... Which doesn't sound good. Maybe the compression algorithm is better than mp3 but I believe compression is the limiting factor in the sound quality of the current Atmos streaming services.

The discussion and claim wasn’t about “more than enough”. It was about what is considered hi-rez and what is better.

24/44 or higher is generally considered by the industry to be high-rez. That a few folks think otherwise - with nothing but “what they consider” is largely meaningless.

Cherry-picking one article out the hundreds and hundreds of supporting and dissenting articles on the topic of what is or isn’t sufficient is also meaningless - and irrelevant to the original discussion.

 

[Toto4Ever]

Almost certainly. Do you have auto-install upgrade on? Are you running version 15.0 or 15.1 on your Apple TV 4K?

Sorry for late reply. I haven’t actually checked yet. I often control from my iPad & looking at softwear updates it’s not clear to me which one is installed. I will investigate further, in the meantime I hope APLLE rectify this issue soon.

 

[Cheezmo]

New pre-release track...

https://music.apple.com/us/album/high-and-lonesome/1578783072?i=1578783093

 

[Cheezmo]

A bunch of tracks from Elton John's "The Lockdown Sessions" that I had added to my library showed up as available today (although they don't show as such on Apple Music). The have the artwork from the collaborators album. Weird, but OK. The Lil Naz X one is in Atmos.

 

[mrcond]

New pre-release track...

https://music.apple.com/us/album/high-and-lonesome/1578783072?i=1578783093

I'm really liking this track!

 

[César]

No Time to Die soundtrack is amazing in Atmos. I was going to say that there's even too much activity on the heights

 

[vegas]

No Time to Die soundtrack is amazing in Atmos. I was going to say that there's even too much activity on the heights

Listening to it right now.)) Excellent music! And I'm going to watch it in cinema tonight.

 

[channelar]

I didn’t see it mentioned yet. John Lennon - Imagine (The Ultimate Collection) was added in Atmos yesterday. On quick initial listen the mix sounds better than before.
https://music.apple.com/us/album/imagine-the-ultimate-collection/1428571018
The Long And Winding Road was also added to Let It Be (2021 Mix).
https://music.apple.com/us/album/the-long-and-winding-road-2021-mix/1582219768?i=1582225929

 

[EricKalet]

A whole bunch of albums and singles out the past 48 hours or so!! Apple Music is really 'delivering on Atmos!!

 

[humprof]

Review of Atmos on Apple Music at IAA. The byline may look familiar. (I think he gets it right!)
https://immersiveaudioalbum.com/202...k-media-player-apple-music-streaming-service/

 

[beerking]

One style of music that I'm now listening to more than before, is Country Music.

One example being this excellent recording...

https://music.apple.com/gb/album/time-tequila-therapy/1580902692?ls
Soz this should be in Listening in Atmos....

Just reading the excellent article by our very own sjcorne, on why Apple's streaming of Spatial Audio is the dogs bollix.

 

[Bob Romano]

There is a new update for the 4k box but the problem is still there

 

[sjcorne]

Has the Atmos mix of Tom Petty's Wildflowers & All The Rest disappeared for anyone else? It's no longer in my library, and I only see the lossless 'Super Deluxe Edition' when searching.

 

[Stupy]

Review of Atmos on Apple Music at IAA. The byline may look familiar. (I think he gets it right!)
https://immersiveaudioalbum.com/202...k-media-player-apple-music-streaming-service/

This is interesting. I thought the bitrate was the same for Apple and Tidal streaming atmos - is this correct? If the bitrate is the same; what is the story with the volume? Are the files fundamentally different?