Dolby Atmos® FAQ

[Sal1950]

Sometimes there is an obvious difference when the bitrate between two sources is so great.

Someone always claims to hear obvious differences between things. People all over the print and web media say the same things about Nodozz $25,000 power cords. LOL

 

[par4ken]

My Atmos question is how do I get my large heavy four foot tall speakers on the ceiling?

 

[Sal1950]

My Atmos question is how do I get my large heavy four foot tall speakers on the ceiling?

Call David Banner for help!

 

[himey]

Someone always claims to hear obvious differences between things. People all over the print and web media say the same things about Nodozz $25,000 power cords. LOL

Personally, in this specific case, the difference is pretty obvious between the compressed, streaming versions and the ones that have made it to blu-ray. To tell a relatively new member how he should be testing the two, especially when you didn't bother to give your own serious opinion, is a bit unfair to him.

 

[himey]

My Atmos question is how do I get my large heavy four foot tall speakers on the ceiling?

Don't let ANYONE tell you bass isn't directional!

 

[ted_b]

Someone always claims to hear obvious differences between things. People all over the print and web media say the same things about Nodozz $25,000 power cords. LOL

That's quite a freaking stretch from a forum member listening to two pieces of the same music and saying one is clearly better to likening it to selling $25,000 power cords! DBT is not always needed when the differences are so obvious. You didn't beat up Edisonbaggins when he basically said the same thing.

 

[MidiMagic]

Call David Banner for help!

He just blew my speakers.

 

[Sal1950]

Personally, in this specific case, the difference is pretty obvious between the compressed, streaming versions and the ones that have made it to blu-ray.

Well if we're really talking about 2 different masters then all bets are off. But if Apple is streaming the same master it should sound the same unless it's being resampled to sub 16/44.1 Redbook data rate.
Take the 2 outputs and plug them into Audacity. If there are audible differences they will show up in the measurements there.

 

[himey]

Well if we're really talking about 2 different masters then all bets are off. But if Apple is streaming the same master it should sound the same unless it's being resampled to sub 16/44.1 Redbook data rate.
Take the 2 outputs and plug them into Audacity. If there are audible differences they will show up in the measurements there.

With that logic, DTS CDs and High resolution blu-ray's "should sound the same".
Spoiler Alert...They don't.

 

[Sal1950]

With that logic, DTS CDs and High resolution blu-ray's "should sound the same".

DTS CD's are highly compressed, different deal.

 

[himey]

DTS CD's are highly compressed, different deal.

So is streaming. Same deal.

 

[Sal1950]

So is streaming. Same deal.

AFAIK, Not according to the streamers.
Can you prove that with measurements?
If so then you would be correct.

 

[marcb]

AFAIK, Not according to the streamers.
Can you prove that with measurements?
If so then you would be correct.

Apple Music surround is Dolby Digital+ upconverted to 24/48 PCM.

 

[Sal1950]

Apple Music surround is Dolby Digital+ upconverted to 24/48 PCM.

And appears to possibly only get worse.

https://learning.dolby.com/hc/en-us/articles/4406039180564-Appendix-C-Dolby-Atmos-Delivery-Codecs-
Dolby AC-4 IMS (Immersive Stereo) is a next generation audio Codec. Dolby AC-4 IMS is used to carry Dolby Atmos at extremely low bit rates. Dolby AC-4 IMS uses Binaural metadata created during the Dolby Atmos mastering process to create a bitstream that is compatible with standard stereo playback devices as well as a virtualized immersive Dolby Atmos experience on mobile devices using headphones or speakers.


Spatial coding is not used in the AC-4 IMS encoding process.


As the AC-4 IMS adoption rate increases, it is important for the mixer to also monitor with headphones using the onboard binaural render in the Dolby Atmos Renderer.

 

[humprof]

And appears to possibly only get worse.

https://learning.dolby.com/hc/en-us/articles/4406039180564-Appendix-C-Dolby-Atmos-Delivery-Codecs-
Dolby AC-4 IMS (Immersive Stereo) is a next generation audio Codec. Dolby AC-4 IMS is used to carry Dolby Atmos at extremely low bit rates. Dolby AC-4 IMS uses Binaural metadata created during the Dolby Atmos mastering process to create a bitstream that is compatible with standard stereo playback devices as well as a virtualized immersive Dolby Atmos experience on mobile devices using headphones or speakers.


Spatial coding is not used in the AC-4 IMS encoding process.


As the AC-4 IMS adoption rate increases, it is important for the mixer to also monitor with headphones using the onboard binaural render in the Dolby Atmos Renderer.

I think that's the core codec for "Dolby Atmos for Headphones" (and mobile devices), though. It wouldn't--shouldn't--be used to deliver Atmos to multi-channel systems.

 

[Sal1950]

I think that's the core codec for "Dolby Atmos for Headphones" (and mobile devices), though. It wouldn't--shouldn't--be used to deliver Atmos to multi-channel systems.

From your lips to Gods ear

 

[humprof]

Here's a sort of "Dolby Atmos 101" podcast:

Dolby Atmos Immersive Audio | Podcast

David Gould, Director of Audio Content Solutions at Dolby Labs, talks to Hugh Robjohns about immersive audio and how Dolby Atmos works.

www.soundonsound.com

 

[~dave~~wave~]

Sweetwater, the giant online music retailer, released this Atmos music production primer today.
Real world examples of hardware prices. (Not for the faint of heart.)

This would seem to mark another inflection point toward more recording studios inquiring about it.

What Is Dolby Atmos Music? - inSync

 

[Mr. Afternoon]

Don't let ANYONE tell you bass isn't directional!

Especially when I'm mixing!
Bass guitar in the rears we go!

 

[alansanchez86]

Question for this beloved forum.
Can a .m4a file contain Dolby Atmos? This is what the file is showing...