Dolby Atmos® FAQ

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Apocalypse Now, Saving Private Ryan & Fury are all outstanding.
Dumbo and the Fantastic Beasts movies too.

Just watched APOCALYPSE REDUX on an older blu ray, and would love to see it in 4K Ultra (although I did stream it a couple of years ago off Netflix or somewhere like that).

However, it was apparently recorded in stereo, and later back surround channels were added (up-mixed? reverbed?). On my old blu ray, at least, the sound was good but not terribly discrete.

How was it handled for the Atmos mix? Does it say?
 
Just watched APOCALYPSE REDUX on an older blu ray, and would love to see it in 4K Ultra (although I did stream it a couple of years ago off Netflix or somewhere like that).

However, it was apparently recorded in stereo, and later back surround channels were added (up-mixed? reverbed?). On my old blu ray, at least, the sound was good but not terribly discrete.

How was it handled for the Atmos mix? Does it say?
The Atmos is awesome.
Here is some history on the 5.1:
 
What Is Dolby Atmos?
Dolby Atmos is an Object Based audio surround system (similar to competing DTS:X and Auro 3D systems). Object based systems are a combination of raw audio channels and metadata that describes the spacial position (in 3D space) and other properties of audio objects. Atmos (and DTS:X & Auro) add height speakers to create a true 3D sound field (5.1 is a 2D sound field).

So Atmos objects are not always locked to a specific channel (speaker), for example, an object can be set to appear in a 'phantom position' (between speakers), or can appear to move between any speakers in the speaker array in any direction. Atmos supports up to 128 simultaneous independent audio objects in a mix.

Furthermore, the intended spacial position can be rendered fairly accurately regardless of the actual speaker position based on the actual Atmos speaker setup during installation, which will include a microphone and software in the AVR to measure speaker distances and gain (volume). The actual individual amplifier output is created during playback based on a combination of encoded mix and the speaker configuration (installation). However, more speakers will provide a better resolution of sound movement.

Dolby Atmos for Home, as delivered on Blu-ray and streaming services, are limited to 16 amplifier channels (similar an 'old' system 15.1 - However, as stated above, unlike traditional multichannel audio systems each channel is not sent to a separate speaker).

View attachment 42420

Dolby intro from their website:
http://download.dolby.com/us/en/technology/dolby-atmos-core-explainer.mp4
Dolby Atmos Objects explained:
https://drive.google.com/file/d/1Tb4uZQ6KwER_kOaH6bDoWxKLtLQWA4Eu/view?usp=sharing

Why was Atmos created?
The three competing Object Based audio systems were primarily created to add rich, realistic sound for movies. With Atmos an audio engineer can ensure a sound can follow an object on the screen, a helicopter circling overhead etc. Hundreds of movies are now available on Blu-ray and 4K UHD blu-ray with Atmos and DTS:X soundtracks. Many movie theaters have one of these systems installed.

Obviously, there are many surround music enthusiasts around the world. So the natural progression is to release Atmos music too. There are already several concerts and audio albums with Atmos mixes, with more coming.


Is Atmos backward compatible with existing equipment?
Atmos content does not require a new codec. It is implemented as an extension within the original Dolby TrueHD (lossless) and Dolby Digital Plus (lossy) codecs. Much like how DTS-HD was an extension to DTS.

Atmos can be delivered along with Dolby TrueHD, typically on blu-ray (BDV and BDA) at around 4000 to 7000kbps or along with Dolby Digital Plus, typically at 640kbps or less for streaming by Netflix, Itunes, Prime, Soundcloud and similar services.

If your AVR does not have an Atmos decoder: If it has a Dolby TrueHD decoder it will decode the TrueHD 'core' to provide 5.1 or 7.1 channels (depending on your setup). In this situation you can playback an Atmos track, but its played back as 5.1 or 7.1 TrueHD. You will not hear the Atmos mix.

Although you need a new AVR to decode these Atmos extensions (older models will simply play the base TrueHD/Digital Plus content), Blu-ray players that fully conform to the Blu-ray specification will support
Atmos without requiring a firmware update.

Modern Media Players with HDMI will also playback Atmos tracks via HDMI pass-through to an Atmos, TrueHD or Dolby Digital Plus compatible AVR.


Do I lose anything by listening to an Atmos mix on a non-Atmos system in 5.1?
The raw musical information is sent to the 5.1 or 7.1 channels from the TrueHD or Dolby Digital Plus mix during Atmos track decoding, so you won't lose the base/core mix. However, the spacial information (location is 3D space) and possibly height Audio will be lost. You may not hear movement/panning or positioning as intended by the Atmos audio mixer.

This will be confirmed once we get more information. I will do more testing shortly but it’s probably release/mix dependent not a generic rule for all.


What is the minimum system requirement to hear a 'real' Atmos mix?
Requirements:
1. An AVR or Surround Processor that has a Dolby Atmos decoder. (All Atmos AVRs I've seen also have DTS:X decoders too. Many also include Auro 3D decoders)
2. A traditional 5.1 or 7.1 speaker layout PLUS at least 2 ceiling or height enabled speakers. Preferably 4.
3. Having enough amplifier channels to drive all the above speakers. Most Atmos AVRs will have 9 or more channels (The Denon AVR-8500 has independent 13 amplifiers).
4. A playback device (e.g. Blu-ray Player, PC or Media player) with HDMI output.

If your existing 5.1 AVR has analog inputs, its also possible to buy a new AVR with 11 or 13 channel pre-amp outs and use that to drive your old 5.1 AVR as an amp only, thus limiting the size/cost of the new AVR.


What are my Atmos Speaker Options?
Dolby Atmos Speaker Configuration Options for Home are listed below, but first, here's the Object audio naming convention:

View attachment 42421

Typical Object Speaker configurations:
  • 5.1.2: A standard 5.1 setup with a pair of “middle” in-ceiling/ceiling-mounted speakers.
  • 5.1.4: A standard 5.1 setup with a front and rear pairs of in-ceiling/ceiling-mounted speakers.
  • 7.1.2: A standard 7.1 setup with a pair of “middle” in-ceiling/ceiling-mounted speakers.
  • 7.1.4: A standard 7.1 setup with a front and rear pairs of in-ceiling/ceiling-mounted speakers.
  • 9.1.2: A 9.1 setup utilizing front wide channels and a pair of “middle” in-ceiling/ceiling-mounted speakers.
A typical 5.1.4 system floor plan (from the Dolby website):
View attachment 42422
1. Seating position
2. Left and right speakers*
3. Center speaker*
4. Subwoofer*
5. Left and right surround speakers*
6. Left and right top front overhead speakers
7. Left and right top rear overhead speakers

* Denotes traditional 5.1 floor speakers

In addition to the number of channels, there’s also two options for additional height speakers: Discrete in-ceiling/ceiling-mounted speakers or 'Dolby Atmos-enabled' speakers utilizing what they call 'reflective speaker technology':

1. Traditional speakers - Advantages: Better sound Disadvantages: Need to run new cabling within ceiling (and up walls)

2. Dolby patented 'Dolby Atmos Enabled' speakers. These are upward-firing drivers positioned on the front and/or rear speakers, they bounce the sound off the ceiling of your living room, giving the impression
that sounds are coming from above you. Advantages: Easier installation Disadvantages: Only suitable for Dolby Atmos, Sound is compromised vs traditional speakers

Typical Atmos Enabled/Upfiring system (from the Dolby website):
View attachment 42424

Typical Atmos system with ceiling speakers:
View attachment 42426


Do Atmos Enabled Speakers Really Work?
Here's an interesting article:
https://www.audioholics.com/frequent-questions/atmos-enabled-speakers

What music is available in Atmos now?
There have been several Atmos music releases as of August 2019, both concerts and albums:

Notable Concerts on Blu-ray:
Imagine Dragons - Smoke & Mirrors Live
KISS - Kiss Rocks Vegas
Michael Schenker's Temple of Rock: On a Mission - Live in Madrid 4K
Mumford & Sons - Dust and Thunder
Roger Waters - The Wall

Notable Albums on Blu-ray:
Booka Shade - Galvany Street
INXS - Kick: 30th Anniversary Edition (includes some Music Videos in Atmos)
Kraftwerk - 3D The Catalogue (Includes Concert and Video in Atmos)
R.E.M. - Automatic For The People (25th Anniversary Edition)
Schiller - Morgenstund
The Beatles - Abbey Road (Sept. 2019 - 50th Anniversary Super Deluxe)

Here's the offical Dolby Atmos Music list (it's not a complete list):
https://www.dolby.com/us/en/experience/dolby-atmos/dolby-atmos-music-titles.html

What music will be available in Atmos soon?
Dolby have recently teamed up Universal Music Group and announced 'several hundred' songs will be mixed and released in Atmos (soon).
https://www.billboard.com/articles/business/8512853/universal-music-group-dolby-atmos-sound-mixing
As of August 2019 it is unclear how the UMG Atmos songs will be distributed, although it seems there will be at least a streaming/download option. Expect more information soon.

Artists mentioned as of August 2019 in various press releases:
Beck, R.E.M. LL Cool J, Wu-Tang Clan, R.E.M., Marvin Gaye, Public Enemy and Snoh Aalegra.

The Beatles’ Sgt Pepper has been mixed in Dolby Atmos for theatrical release to celebrate the groundbreaking album’s 50th anniversary. And more recently David Gilmour returned to Abbey Road Studios in 2017 for an Atmos mix of his Pompeii Live In Concert. Both mentioned here:
https://www.abbeyroad.com/news/abbey-roads-new-mix-stage-2243
Miles Davis’ - Kind of Blue mentioned here:
https://www.mixonline.com/the-wire/pmc-demonstrates-dolby-atmos-music-at-high-end-munich
INXS - Live Baby Live in 4K and Atmos for theatres here:
https://newmusicweekly.com/inxs-wembley-concert-to-hit-movie-theatres/
Atmos seems to be the market leader in object based audio, dominating the Movie space, there are also many DTS:X movies, Auro 3D has a few classical music only releases.


What about Atmos Upmixing stereo and quad music?
New AVRs with Atmos decoders also provide an onboard Atmos upmixer. This is more advanced than previous Dolby upmixer generations. The Atmos operates on stereo, quad, 5.1 and latest 7.1 Dolby TrueHD mix.

The system is capable of steering individual frequency bands from each channel to create up a matrixed Atmos environment based on your speaker configuration. Atmos upmixer will not send redirected content
to speakers between the front left, center, and right speakers in order to minimize the impact on the front stage.

These Atmos enables AVRs typically also do DTS Neural:X upmixing too.


Are there Atmos test files or Demos available?
Atmos Channel Test files in MKV format for the following:

5.1.2, 5.1.4, 7.1.2, 7.1.4 and 9.1.6

There is also a short Atmos demo from Dolby with an interesting couple of 3D graphics explaining the difference between 'conventional' 5.1 mixes and Object mixes)

Link: https://drive.google.com/drive/folders/1NjSmU8j-G7be_shGoT2L0yeikeHsfWhe?usp=sharing

The Kodi Wiki also has quite a few HD Audio samples, including Atmos/DTS:X:
Link: https://kodi.wiki/view/Samples


Can I convert Atmos to FLAC to play in my car, on PC or Media Player?
FLAC is limited to 8 channels. It is possible to convert an Atmos track’s legacy TrueHD to 5.1 or 7.1 FLAC but this will not contain the Atmos extensions (height and special metadata) so it can never reproduce the true Atmos mix during playback.

It is possible to copy the Atmos codec audio track (unconverted original) in its original container (m2ts for BDA) or into another container that supports TrueHD (MKV, MKA, MP4) to play back via HDMI Passthrough to an AVR for Atmos decoding. (Most content will have DRM so ripping/conversion software will be required, the usual suspects that support TrueHD will support Atmos).

There are no known Atmos decoders except for those within Atmos licensed AVRs and Surround Processors. So Atmos playback must always include HDMI from an external ‘player’ to bitstream to your Atmos AVR/Processor.

Atmos playback from a PC or Media Player is poosible with HDMI bitstreaming using Foobar (with ffmpeg plugin), Kodi and Jriver software.

Playback of Atmos files in Kodi:
https://www.quadraphonicquad.com/fo...hd-and-dts-x-dts-hdma-audio-only-files.26799/

More Reading?
https://www.audioxpress.com/article/object-based-audio-and-sound-reproductionhttps://www.soundonsound.com/techniques/dolby-atmos-ministry-sound

DISCLAIMER: Fair use is claimed on all images and test files, as their purpose is only for the promotion of Dolby Atmos music, testing and technical evaluation for our members. QuadraphonicQuad is a non-profit, non-sponsored website.

LAST EDITED: 2019-8-13
Wonderful explanation. I'm wondering about frequency range of the Atmos channels. From my listening I've only noticed mid-range & highs. Not sure how it would sound with some mid bass.
Might not be realistic for home use ???
 
Oh brother, I can't believe I am even thinking about Atmos but here goes. I love my 5.1.
I will be taking a 12' X 14' bedroom in my house and making it a designated listening room with TV of course. I will be looking at the 12' wall so the sound field will be rectangle.
I know that if there ever was a time this is it.
I have 5.1 as of this writing and always enjoyable..
Garry's first post is so awesome.
It looks like 4 in the ceiling is best?
Can you do the ceilings without the 7.1 on the floor?
Can you do 2 in the ceiling, where at front, middle or rear?
I am not intimated with the floors as when setting up on the final day, moving speakers a little here and a little there for proper imaging is not hard.
When they are in ceiling they cannot be moved around, what if after awhile I want to move the listening spot a little front or a little rear? Easy to change the floors, but what about ceilings?
Ditch the thought of Atmos and focus on 7.1?
Ever since I was 10 years old I always winged it with audio placement more or less, but this likely will be my final resting place so I don't want to blow it.
 
Oh brother, I can't believe I am even thinking about Atmos but here goes. I love my 5.1.
I will be taking a 12' X 14' bedroom in my house and making it a designated listening room with TV of course. I will be looking at the 12' wall so the sound field will be rectangle.
I know that if there ever was a time this is it.
I have 5.1 as of this writing and always enjoyable..
Garry's first post is so awesome.
It looks like 4 in the ceiling is best?
Can you do the ceilings without the 7.1 on the floor?
Can you do 2 in the ceiling, where at front, middle or rear?
I am not intimated with the floors as when setting up on the final day, moving speakers a little here and a little there for proper imaging is not hard.
When they are in ceiling they cannot be moved around, what if after awhile I want to move the listening spot a little front or a little rear? Easy to change the floors, but what about ceilings?
Ditch the thought of Atmos and focus on 7.1?
Ever since I was 10 years old I always winged it with audio placement more or less, but this likely will be my final resting place so I don't want to blow it.
I know the official Dolby Atmos site has all the configuration diagrams on it. I also believe the system software adjusts for speaker placement.
 
Would you do it J-Pup? I guess the built in correction is like Audessy or similar? You see I am still in manual mode.;)
Oh man, it’s never just cut and dry with this audio stuff is it! Let the silicon tell me where my sweet spot is- uh probably not:D I feel an up-mix of Zappa’s Cyborg coming on:LOL:
 
I have a 7.2 setup in my home with an Atmos capable amp but no height speakers installed. Does anyone know if there is a benefit to playing an Atmos encoded track without them? Do you gain anything as opposed to the "regular" 7.1 mix, or is it pointless unless you have height speakers? Does it vary from album to album?
 
I am not intimated with the floors as when setting up on the final day, moving speakers a little here and a little there for proper imaging is not hard.
When they are in ceiling they cannot be moved around, what if after awhile I want to move the listening spot a little front or a little rear? Easy to change the floors, but what about ceilings?
do you have to open up walls and ceilings to install the heights? I guess i'm asking why you cant set up for 5.1, find your sweet spot, then install the heights?
 
do you have to open up walls and ceilings to install the heights? I guess i'm asking why you cant set up for 5.1, find your sweet spot, then install the heights?
If I did add the ceilings whether they be in ceiling (flush mount) or the ceiling hanging down kind, don't know what they are called, would have to be done before. I would dread the thought of bringing in all that equipment and have a room full of sheet rock dust.
 
I have been reading and you tubing , also went to audio store and I am going to take the DOLBY ATMOS
plunge with 4 flush mount in ceiling speakers, this will likely be a couple months from now.
With all the research I have been doing I have come to some conclusions:
1. Your 5.1 system needs to be perfect, this is where all the energy needs to be as it is the foundation of Atmos. Additional speakers will not make a shitty 5.1 sound better.
2. My expectation is if done well and correct there will be an added audio feature but it won't be a jump like 2.0 to 5.1, that still is your biggest improvement.
3. Up firing speakers are, well, I'm not going to do it, I will only consider doing it in discrete fashion.
4. All these speakers are a drain on the AVR, there is too much power being taken from the AVR. In my case I have a 3 channel amp and a 2 channel amp for my 5.1. As I am in my thought process I believe I will be adding a smaller pre amp/amp for the additional 4 height speakers, not sure of the watts yet, but probably something low key.
5. Placement is important in the height speakers so I will be thoughtful in advance before I cut the holes, but again, they are not as important as the 5.1.

Kind of reminds me when in the early 90's I got my first 5.1 system by Phillips, all in the box. A little exciting, didn't know what to except but when I put on that Jurassic Park Laser Disc, wow ee..
 
I have been reading and you tubing , also went to audio store and I am going to take the DOLBY ATMOS
plunge with 4 flush mount in ceiling speakers, this will likely be a couple months from now.
With all the research I have been doing I have come to some conclusions:
1. Your 5.1 system needs to be perfect, this is where all the energy needs to be as it is the foundation of Atmos. Additional speakers will not make a shitty 5.1 sound better.
2. My expectation is if done well and correct there will be an added audio feature but it won't be a jump like 2.0 to 5.1, that still is your biggest improvement.
3. Up firing speakers are, well, I'm not going to do it, I will only consider doing it in discrete fashion.
4. All these speakers are a drain on the AVR, there is too much power being taken from the AVR. In my case I have a 3 channel amp and a 2 channel amp for my 5.1. As I am in my thought process I believe I will be adding a smaller pre amp/amp for the additional 4 height speakers, not sure of the watts yet, but probably something low key.
5. Placement is important in the height speakers so I will be thoughtful in advance before I cut the holes, but again, they are not as important as the 5.1.

Kind of reminds me when in the early 90's I got my first 5.1 system by Phillips, all in the box. A little exciting, didn't know what to except but when I put on that Jurassic Park Laser Disc, wow ee..
Oh I believe you'll be fine Mark given you already have great gear; and aren't some of those in-ceiling speakers adjustable as to directionality, at least able to be rotated with a 45 degree downward angle?
 
I really want to take the leap to Atmos, DTS-X, etc., and from my research, I've pretty much decided to get a factory refurbished avr, probably Denon or Marantz from accessories4less, and some high quality outdoor speakers for the 4x ceiling speakers. I don't want to cut into my ceiling, plus the outdoor style speakers come with their own built in brackets for mounting into a ceiling joist, with easy on-the-fly angling capabilities and adjustments built right in. Seems like it would be much simpler to install and more flexible for fine tuning.

AVR: $700+
Outdoor Speakers (x4): $200~$400+
= $900~$1100++
 
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Found an used Denon AVR 4100W from some years back for a good price.Already had some high mounted speakers in front.Bought some outdoor speakers for rear hight 2 + 25 m speaker cable and now have Atmos 5.1.4. :cool: I use preout for 5.1 to my P7's second 5.1 input and pre out from Height 2 to spare amp.The only amps I use in the AVR are Height 1.
Total cost $600.Sounds great!:)
 
Well, the audio room (as well as the entire lower level finishing project) is well under way and I've wired the 5.1.4 ATMOS ceiling speaker wire (as well as smurf tubes for the surround cabling, etc). Insulation (and drywall outside of audio room) is done and I'm in a "no turning back" mode now. :) I am excited to be reporting this (especially given the at-home quarantines being the new normal) but worried the trades will be told to stay home too...and wondering if this thing will be done anytime in the next 18 months. First world problems.....stay tuned.

Anyway...ATMOS is now in my near future. Yea!
 
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