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post #1 of 3 Old 05-11-2020, 03:43 PM - Thread Starter
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Atmos object calculations

Can someone point to a right direction how to go about understanding how the Atmos audio placement is created/calculated. I would like to understand how the movie content audio (typically say 7.1 atmos) becomes something like 16 channel atmos. Are the processors just averaging neighboring atmos channels across the ceiling or doing something much more elaborate?
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post #2 of 3 Old 05-11-2020, 07:03 PM
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The wikipedia page has a brief description under "Implementation and differences from commercial implementations"
https://en.wikipedia.org/wiki/Dolby_Atmos

Dolby has a doc that tries to explain
https://www.dolby.com/us/en/technolo...me-theater.pdf

In short, Dolby Atmos supports up to 24 "floor" speakers, a subwoofer LFE channel, and 10 elevation speakers. The most we've seen in a mainstream AVR is 13 channels (Denon AVR-X8500H or Marantz sibling).
Besides these channels, dolby Atmos can describe up to 118 "object" channels with data to support how the sound should pan across the speakers known by the system.
It implies that the AVRs are limited by the number of speakers "described"/implemented in the specific models, with logical names and expected positions prescribed by Dolby.

Dolby's layout guide only goes up to 11.1.8, again implying that there are other logical speaker names we haven't seen implemented yet.
https://www.dolby.com/us/en/speaker-...des/index.html

DTS:X and/or Auro3D probably do something similar, all derived from movie theater setups.

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Originally Posted by 104av View Post
Can someone point to a right direction how to go about understanding how the Atmos audio placement is created/calculated. I would like to understand how the movie content audio (typically say 7.1 atmos) becomes something like 16 channel atmos. Are the processors just averaging neighboring atmos channels across the ceiling or doing something much more elaborate?
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post #3 of 3 Old 05-15-2020, 12:23 PM
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Quote:
Originally Posted by 104av View Post
Can someone point to a right direction how to go about understanding how the Atmos audio placement is created/calculated. I would like to understand how the movie content audio (typically say 7.1 atmos) becomes something like 16 channel atmos. Are the processors just averaging neighboring atmos channels across the ceiling or doing something much more elaborate?
Atmos sound is rendered by your audio processor (think of it as computer graphics). The audio container (Dolby TrueHD/Dolby Digital Plus) contains the 7.1 base channels and on top of that meta data describing where all or some of that should be placed in the 3D space around your room as objects. Your processor know which speakers you have available and use the ones closest to where the sound object is intended to be played back.

Home Atmos supports up to 34 channels in a 24.1.10 configuration. These are all available if you have a Trinnov Altitude processor.

The more channels you have the more precise the sound objects can be rendered.
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Tower Cinema - 9.1.6 in a 12'x12' room
Input : Nvidia Shield TV, Panasonic DMP-UB400
Magic : Marantz SR7010, Marantz SR6010, 2x NAD T743
Output : Panasonic TX65EZ952B, SVS PB13 Ultra, Monitor Audio GSLCR 2xGS20 2xGS10 4xGSFX 6xBX1

Last edited by Mashie Saldana; 05-15-2020 at 12:28 PM.
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