• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required as is 20 years of participation in forums (not all true). Come here to have fun, be ready to be teased and not take online life too seriously. We now measure and review equipment for free! Click here for details.

Spatial Audio -- warning from a producer/engineer

DeLub

Member
Joined
Jun 16, 2020
Messages
79
Likes
112
Location
The Netherlands
My understanding is that Apple stores, depending on the source files they get delivered, multiple versions of the same track. During playback it decides which version to stream to you depending on your settings and device capabilities.
The available versions:
  • Compressed AAC file, stereo (a subset of which have been marked 'Apple Digital Master'); these ar the 'traditional' files
  • Lossless ALAC file, stereo, 16 or 24 bits, 44.1 or 48kHz
  • Hires Lossless ALAC, stereo, 16 or 24 bits, > 48kHz
  • Compressed ATMOS file, at least playable through Apple TV on Atmos capable AVR
  • Compressed pre-rendered ATMOS file, downmixed to stereo, playable on any device, meant to be listened to on headphones
 

DeLub

Member
Joined
Jun 16, 2020
Messages
79
Likes
112
Location
The Netherlands
Tidal has an issue where Atmos tracks are around 20db more quiet then stereo tracks which is a big problem.
Might this be because Dolby files are normalised to -31dB by Apple TV? And normal Tidal files are either too loud (cf. loudness wars), or normalised to -14dB (or something around that value).
 

polmuaddib

Active Member
Forum Donor
Joined
Mar 1, 2020
Messages
250
Likes
299
Might this be because Dolby files are normalised to -31dB by Apple TV? And normal Tidal files are either too loud (cf. loudness wars), or normalised to -14dB (or something around that value).
Whatever the reason, it's been some time, people have complained and still Tidal can't correct that for their Apple TV app? I am no coder, but I suppose it would be a simple line of code: If play atmos file on apple tv - make volume normal.
 

Sal1950

Master Contributor
The Chicago Crusher
Forum Donor
Joined
Mar 1, 2016
Messages
9,265
Likes
9,014
Location
Central Fl
Whatever the reason, it's been some time, people have complained and still Tidal can't correct that for their Apple TV app?
Along with that sneeky excuse for DRM called MQA, that's one more great reason to
JUST SAY NO
to Tidal. Flip a $100 for a Gen 2 Apple TV 4K box and get some of the best immersive and hi-def music you've ever heard streamed to you for a lousy $10 a month.
 

Soundmixer

Active Member
Joined
Mar 8, 2021
Messages
250
Likes
133
I think people are confusing bad mixes with a limitation of the stereo format. The format is not limited. If the desire is to have the audio image sound "bigger" without making them sound far away, a good engineer can easily do that in stereo. Putting the reverb behind your head is not going to help a bad mix.
Actually, the stereo format is limited...at least spatially. What makes Atmos and multichannel in general better than stereo in many ways is to be able to position things correctly and naturally within a 360-degree vertical and horizontal soundfield. If you are recording live, you can properly place the audience and reverberation where it should be. You can't do that with stereo. In stereo, you have to equalize the hell out of phantom imaging between the speakers to compensate for a presence dip. With multichannel and Atmos, you have a solid center channel to work with, which makes it easier to mix with less processing.

I've been mixing with Atmos since 2015, and when done well, music mixed and encoded in Atmos can sound extremely good, much better than stereo IMO.
 

Spocko

Addicted to Fun and Learning
Forum Donor
Joined
Sep 27, 2019
Messages
990
Likes
1,811
Location
Southern California
Actually, the stereo format is limited...at least spatially. What makes Atmos and multichannel in general better than stereo in many ways is to be able to position things correctly and naturally within a 360-degree vertical and horizontal soundfield. If you are recording live, you can properly place the audience and reverberation where it should be. You can't do that with stereo. In stereo, you have to equalize the hell out of phantom imaging between the speakers to compensate for a presence dip. With multichannel and Atmos, you have a solid center channel to work with, which makes it easier to mix with less processing.

I've been mixing with Atmos since 2015, and when done well, music mixed and encoded in Atmos can sound extremely good, much better than stereo IMO.
In terms of speaker count, what is the optimal number of speakers to capture accurately every intended spatial nuance of a well done Atmos mix: 7.1.4 or 9.1.6, or more?
 

Soundmixer

Active Member
Joined
Mar 8, 2021
Messages
250
Likes
133
In terms of speaker count, what is the optimal number of speakers to capture accurately every intended spatial nuance of a well done Atmos mix: 7.1.4 or 9.1.6, or more?
It depends on the size of the room and the number of seats you have to cover (and your budget of course). The larger the room, the more speakers it takes to properly reproduce the spatial qualities of Atmos and X. The reality in the market is that 7.1.4 gets immersive in more rooms than 9.1.6 because the former can be found in a bunch of AVR's and Pre-pro's, but not the latter. If you want 9.1.6, you have to pay some coin to get it.
 
Last edited:

sarumbear

Major Contributor
Forum Donor
Joined
Aug 15, 2020
Messages
1,757
Likes
1,574
Location
Southampton, UK
It depends on the size of the room and the number of seats you have to cover (and your budget of course). The reality in the market is that 7.1.4 gets immersive in more rooms than 9.1.6 because the former can be found in a bunch of AVR's and Pre-pro's, but not the latter. If you want 9.1.6, you have to pay some coin to get it.
I‘m confused. You said 7.1.4 gets more immersive than 9.1.6. Have I misunderstood you or you mean less speakers are more immersive?
 

Soundmixer

Active Member
Joined
Mar 8, 2021
Messages
250
Likes
133
I‘m confused. You said 7.1.4 gets more immersive than 9.1.6. Have I misunderstood you or you mean less speakers are more immersive?
Read what I said again.

"The reality in the market is that 7.1.4 gets immersive in more rooms than 9.1.6 because the former can be found in a bunch of AVR's and Pre-pro's, but not the latter."

Translation....there are more AVR's and Pre-pro's sold with 7.1.4 than 9.1.6.
 

sarumbear

Major Contributor
Forum Donor
Joined
Aug 15, 2020
Messages
1,757
Likes
1,574
Location
Southampton, UK
Read what I said again.

"The reality in the market is that 7.1.4 gets immersive in more rooms than 9.1.6 because the former can be found in a bunch of AVR's and Pre-pro's, but not the latter."

Translation....there are more AVR's and Pre-pro's sold with 7.1.4 than 9.1.6.
Thank you for clarification. I was confused as you were using the adjective ‘immersive‘ as a noun.

However, as Dolby Atmos is channel indipendent why would you differentiate between the number of speakers
 

Soundmixer

Active Member
Joined
Mar 8, 2021
Messages
250
Likes
133
Thank you for clarification. I was confused as you were using the adjective ‘immersive‘ as a noun.

However, as Dolby Atmos is channel indipendent why would you differentiate between the number of speakers
Easy answer. Atmos is channel independent from a mixing and reproduction perspective, but it does require a certain amount of speakers to accurately reproduce the immersive/pinpoint-like effect. In a very small room, 5.1.2 may suffice. Dolby recommends 7.1.4 at the minimum, but I found I got great results in a small room with 7.1.2. As the room gets larger and larger, and you have more seats to cover, you logically need more speakers to accurately reproduce Atmos. If I followed your logic, I could install a 5.1.2 system in a large room, and it should work - but it doesn't.

Atmos is a scalable system in that it works in large rooms with 64 speakers all the way down to very small rooms with 8 speakers.
 

sarumbear

Major Contributor
Forum Donor
Joined
Aug 15, 2020
Messages
1,757
Likes
1,574
Location
Southampton, UK
Easy answer. Atmos is channel independent from a mixing and reproduction perspective, but it does require a certain amount of speakers to accurately reproduce the immersive/pinpoint-like effect. In a very small room, 5.1.2 may suffice. Dolby recommends 7.1.4 at the minimum, but I found I got great results in a small room with 7.1.2. As the room gets larger and larger, and you have more seats to cover, you logically need more speakers to accurately reproduce Atmos. If I followed your logic, I could install a 5.1.2 system in a large room, and it should work - but it doesn't.

Atmos is a scalable system in that it works in large rooms with 64 speakers all the way down to very small rooms with 8 speakers.
Thank you. I finally understand what was your post meant. I have a 11.4.4 home theatre, but I still prefer listening music in stereo on my music room. I know, I'm old. :)
 
OP
A

Ata

Senior Member
Forum Donor
Joined
May 6, 2021
Messages
304
Likes
242
Location
Adelaide, Australia
An interesting and relevant article on Apple and Atmos: https://scobleizer.blog/2021/09/30/dolby-atmos-and-apples-rewritten-audio-stack

"What impressed me is that Apple totally rewrote its audio stack on all of its devices, and put two AI chips in its headphones to enable Atmos in headphones. Apple’s audio renderer is the best in the business, Sean Olive, head of R&D at Harman, who makes JBL, told me. He should know, he’s one of the few humans who has built a double-blind audio testing lab, among other feats."
 

JJB70

Major Contributor
Forum Donor
Joined
Aug 17, 2018
Messages
2,436
Likes
5,207
Location
Singapore
I think that when properly done spatial audio is great, better than stereo. Putting aside the issue of poor mixes which is hardly unusual for new-ish formats the big barrier remains the hassle of setting up a speaker system. As well as the hassle of buying and positioning them all, wiring is expensive unless you are happy with wires everywhere. Wireless should be a godsend and transformative technology for multi-channel audio but it doesn't seem to have really taken off. The other barrier is that while it may be better, the sound experience of regular stereo and even mono is very good. When most people found that sound bars with sub-woofers offered most of the sound improvement of a full home theatre set-up with a lot less hassle and cost sales of AV receivers and speaker packages collapsed, for most people I don't think the benefits justify the effort.
 
OP
A

Ata

Senior Member
Forum Donor
Joined
May 6, 2021
Messages
304
Likes
242
Location
Adelaide, Australia
When most people found that sound bars with sub-woofers offered most of the sound improvement of a full home theatre set-up with a lot less hassle and cost sales of AV receivers and speaker packages collapsed, for most people I don't think the benefits justify the effort.

I think this statement somewhat conflates sound quality with convenience and pricing. Soundbar + mediocre sub offers the right mix of convenience and price, but sound quality-wise even a basic 2.1 setup will be noticeably better. The abysmal sound from today's flatscreen TVs makes it a must to upgrade the sound, and the delta from TV sound to soundbar+sub sound is both noticeable and available in the same shop that sells TVs. In most cases, you'd need to go to a large specialised electronics store to obtain a better than entry level multichannel setup in the same transaction as the TV.
 

JJB70

Major Contributor
Forum Donor
Joined
Aug 17, 2018
Messages
2,436
Likes
5,207
Location
Singapore
I think this statement somewhat conflates sound quality with convenience and pricing. Soundbar + mediocre sub offers the right mix of convenience and price, but sound quality-wise even a basic 2.1 setup will be noticeably better. The abysmal sound from today's flatscreen TVs makes it a must to upgrade the sound, and the delta from TV sound to soundbar+sub sound is both noticeable and available in the same shop that sells TVs. In most cases, you'd need to go to a large specialised electronics store to obtain a better than entry level multichannel setup in the same transaction as the TV.
I think we have to differentiate between audio enthusiasts and the mainstream. I don't think sound bars are as good as a well set up true AV surround system but many sound bars now are very good. Most people aren't interested in chasing ultimate sound quality, they want something that sounds good and gives a kick in the low end when necessary. Whether or not something is better is often a slightly pointless question, what matters is whether something meets the expectation and needs of the user. And sound bars deliver that to most people. We have a Samsung soundbar, I honestly can't remember the model but it is a pretty good one, apparently it made use of some fancy Harman know how. Is it the ultimate in sound quality? No, but that's not why I bought it. Is it good enough for TV and movies? Yes. What surprised me slightly was it is actually more than acceptable for music, I listen to classical music on it sometimes and really do not feel short changed or that I am losing anything significant.
 
OP
A

Ata

Senior Member
Forum Donor
Joined
May 6, 2021
Messages
304
Likes
242
Location
Adelaide, Australia
Apple don't own schitt,so far Apple the lastest player in the Atmos, spacial audio streaming game.

Apple own their software codebase, and the claim in the article is that their Atmos implementation has been redone and is (one of) the best in the industry.

Of course, by default Apple do not own any Atmos content, the publishers get to create and own that. I am not aware of Apple publishing any music on its own, ergo you are right if you are speaking specifically content ownership.
 

dmac6419

Major Contributor
Joined
Feb 16, 2019
Messages
1,235
Likes
729
Location
USofA
Apple own their software codebase, and the claim in the article is that their Atmos implementation has been redone and is (one of) the best in the industry.

Of course, by default Apple do not own any Atmos content, the publishers get to create and own that. I am not aware of Apple publishing any music on its own, ergo you are right if you are speaking specifically content ownership.
Apple implementation is no better than the the two streaming platforms before them nor will it be better than who comes after them.thank you my friend for your wise words you are a sage,lol
 
OP
A

Ata

Senior Member
Forum Donor
Joined
May 6, 2021
Messages
304
Likes
242
Location
Adelaide, Australia
Apple implementation is no better than the the two streaming platforms before them nor will it be better than who comes after them.thank you my friend for your wise words you are a sage,lol

Hey mate,

What are you trying to say? I have the feeling we are talking about entirely different things. That'd be very helpful.

Cheerio
 
Top Bottom