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The official Dolby Atmos thread (home theater version) – Check out post 1 first

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#1 · (Edited)
Last update: 02.04.2023



Official Dolby Atmos at home website

Dolby on Atmos for the home
Dolby Atmos Speaker Setup
Ceiling-firing speakers ("Atmos-enabled speakers")
http://www.dolby.com/us/en/technologies/dolby-atmos/dolby-atmos-enabled-speaker-technology.pdf
Speaker installation guidelines
http://www.dolby.com/us/en/technolo...tmos-home-theater-installation-guidelines.pdf
If you're more the visual type of guy here's a good video explaining the basics of placing your Atmos speakers:

Insights from a recording and mixing engineer


Technical specification for studios wishing to employ a 7.1.4 home entertainment Dolby Atmos monitoring setup
Dolby Atmos Home Entertainment Studio
Certification Guide


Blog posts
Dolby Atmos: Coming soon to a living room near you - Lab Notes
Dolby Atmos for home theaters: FAQ - Lab Notes


Dolby Patent Application
http://www.freepatentsonline.com/WO2014036085A1.html


Dolby on Atmos for movie theaters
Wayback Machine

Specifications for movie theaters
Wayback Machine


How Atmos content is created
Wayback Machine


How Atmos is encoded into TrueHD and Dolby Digital Plus
https://professional.dolby.com/site...on/dolby-atmos/dolby_atmos_renderer_guide.pdf


avsforum.com Members Atmos & Auro Configuration Spreadsheet (at Google Docs, maintained by user kokishin)


Atmos test tone downloads (E-AC-3 audio in .mp4 container)
https://www.dolby.com/us/en/guide/test-tones.html

Other Dolby trailer downloads
 
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#922 ·
Rich. A counterpoint and some clarification

Atmos for the theater works incredibly well because Dolby approves and certifies all installations. While this adds cost, it makes for a better consistency of the product.

But they don't do any kind of speaker remapping...

It isn't part of the feature set for theatrical Atmos today.

So to imply it will be an omission isn't factual... It doesn't exist in the theatrical world, so it's not being left out. (I might be misinterpreting your comment...)
This is probably my unartful wording, but the benefit of is that audio objects are encoded with position information.
When played back in a particular theater, the sounds using the speakers and positions present the sounds in the proper locations.

Initially, I and others thought that the home Atmos would know the speaker layout in the home and perform the same function for the X.1 channels present.
Some home theaters diverge from ideal placement, so it might be possible, to use positional information improve existing sound tracks as well.
Now I'm confused!
 
#923 ·


I hope you can give us some impressions regarding AccuuEQ..

No LR or Sub eq? Am I misinterpreting the literature? I know you have contacts and access at Onkyo but the ditching of audyssey makes this a no go for me....

Maybe you can talk to your insiders for some insight into their new solution. Timbre marching will be more important with Atmos and not correcting the mains or sub seems like heresy.

EDIT..

Did some digging on AccuEQ..

I wasn't wrong...

Straight from the horses mouth...

http://forums.onkyousa.com/viewtopic.php?t=5753&p=21276

"AccuEQ: There are advantages and disadvantages to any room calibration system.

Many calibration systems apply equalization to all channels. This in turn results in your speaker producing an “Equalized Sound” not necessarily the natural sound of your speakers.

The main benefit of AccuEQ is that it does not apply an Equalized effect to Front channels and Subwoofer. This allows the natural sound of your speakers to be heard while taking into consideration things such as room furnishings, speaker distance and speaker type.

We will continue to refine AccEQ as we move forward to make it the best calibration system available.
"
Trust me. I am not happy with the loss of Audyssey. To me it would be like having a McIntosh MX151 without Room Perfect. Of course I am very curious how Atmos will work. Of course no matter what I will be wondering if it could have sounded better with XT32 or a newer version. Most likely.
 
#924 ·
Now I'm confused!
Let me take a stab at this.

The Atmos format is object-based, and the objects do contain metadata that positions the objects in 3-dimensional space. The rendering engine knows what your speaker layout is, because you told it so when you set it up, and maps the objects to the best combination of speakers to render that object in your home theatre. But the rendering engine is *approximating* your speaker layout based on Dolby's guidelines - if you tell it you have a 5.1.2 system, it is assuming L,C,R, Left Surround, Right Surround, Left Top, Right Top (or Atmos-enabled reflective speakers to simulate those last two). It does not know if your Left Surround is at 90 degrees or 110 degrees, how high up the wall you've placed your surrounds, or where exactly on your ceiling your height speakers are.

What we've learned from FilmMixer is that Atmos in the cinema environment works much the same way - the rendering engine is making assumptions about speaker placement, assumptions based on Dolby guidelines. Presumably if a theater designed an Atmos auditorium with 64 speakers, but scattered them randomly around the room, Dolby would simply say no, not gonna certify that as an Atmos system.

In other words, the speaker remapping that many people are lamenting the absence of was never a part of the system to begin with.
 
#926 ·
Rich. A counterpoint and some clarification



What I think will be the next step after this initial launch is a product with 9.1.4. Front wides will really enhance the way objects move off the screen and into the room. I think one of the manufactures confirmed they will have a 9.1.2 setup at launch however.
I am interested in Dolby's approach to the front wides, since they've never been utilized by Dolby in a home theater environment (the only home theater use for wides to date is with DTS Neo:X, Audyssey DSX and probably some other up mixing algorithms I'm not familiar with).

In the theatrical implementation of Atmos are the side surround speakers up near the screen toed back towards the audience? Hypothetically speaking do you think additional side surround speakers in an Atmos home theater would be in the same spot as the wides in a Neo:X setup?

And an unrelated question, but one that I think will be beneficial to all reading - can you confirm what the 9.1 channel beds are for theatrical Atmos?
 
#927 ·
I am interested in Dolby's approach to the front wides, since they've never been utilized by Dolby in a home theater environment (the only home theater use for wides to date is with DTS Neo:X, Audyssey DSX and probably some other up mixing algorithms I'm not familiar with).

In the theatrical implementation of Atmos are the side surround speakers up near the screen toed back towards the audience? Hypothetically speaking do you think additional side surround speakers in an Atmos home theater would be in the same spot as the wides in a Neo:X setup?

And an unrelated question, but one that I think will be beneficial to all reading - can you confirm what the 9.1 channel beds are for theatrical Atmos?
Last one first: it's the 7.1 configuration just like before with two additional channels for the top left/right.

It's hard to know yet if the front wides will need to be positioned like the cinema white papers suggest or more like DTS Neo:X (what little we have to go on seems to focus on the top surrounds). In the cinema, they're side wall speakers that are placed between the regular side surround arrays and the front screen speakers to fill in the gap. They're aimed towards the main listening area of the theater.
 
#928 · (Edited)
Just remember this.. Atmos is a proprietary format... studios aren't going to have the choice of what codec to use for films already mixed in Atmos but not MDA. In the end a big part of the success of either format will come down to the software and titles available for each one..
The producers of TV shows like Game of Thrones presumably face an interesting and on-going question about how and when to add immersive audio to their product production (but not yet broadcast!) so as to maximize potential rerun revenue once ATSC 3.0 TV is deployed. The problem would seem to be complicated by the fact that--so far as I know--there is as yet no decision as to which immersive audio 'codec' will be implemented with ATSC 3.0. That might suggest that they should mix 'now' with an open vs closed platform to maximize flexibility once real ATSC 3.0 audio format decisions are made.

In the meantime, there remains the opportunity to use any TV content mixed with immersive audio to boost post season BD sales: "Watch the last season again at home, this time with improved, immersive audio NOT AVAILABLE IN THE BROADCAST VERSION!"

I'm sold! :D
_
 
#929 ·
I am interested in Dolby's approach to the front wides, since they've never been utilized by Dolby in a home theater environment (the only home theater use for wides to date is with DTS Neo:X, Audyssey DSX and probably some other up mixing algorithms I'm not familiar with).

In the theatrical implementation of Atmos are the side surround speakers up near the screen toed back towards the audience? Hypothetically speaking do you think additional side surround speakers in an Atmos home theater would be in the same spot as the wides in a Neo:X setup?

And an unrelated question, but one that I think will be beneficial to all reading - can you confirm what the 9.1 channel beds are for theatrical Atmos?
Yes the front surrounds are toed towards the center of the theater.

The 9.1 is standard 7.1 (L C R LSS RSS LSB RSB ARRAYS) + two overhead arrays (OH L AMD R).

If you want access to the now available Left and Right Extra screen channels, you have to use an object.
 
#930 ·
In the theatrical implementation of Atmos are the side surround speakers up near the screen toed back towards the audience? Hypothetically speaking do you think additional side surround speakers in an Atmos home theater would be in the same spot as the wides in a Neo:X setup?
Like the additional screen speakers, the first two or three surround speakers just outside the screen (added for Atmos) are for objects. Rearward of these speakers is where the side surround array starts and those are the speakers that playback the surround channel beds.

The speakers just outside the screen correlate with wides at home. Maybe not in precise angle, but they're outside the screen and located between the fronts and surrounds, just like wide speakers are.
 
#931 · (Edited)
Let me take a stab at this.

The Atmos format is object-based, and the objects do contain metadata that positions the objects in 3-dimensional space. The rendering engine knows what your speaker layout is, because you told it so when you set it up, and maps the objects to the best combination of speakers to render that object in your home theatre. But the rendering engine is *approximating* your speaker layout based on Dolby's guidelines - if you tell it you have a 5.1.2 system, it is assuming L,C,R, Left Surround, Right Surround, Left Top, Right Top (or Atmos-enabled reflective speakers to simulate those last two). It does not know if your Left Surround is at 90 degrees or 110 degrees, how high up the wall you've placed your surrounds, or where exactly on your ceiling your height speakers are.

What we've learned from FilmMixer is that Atmos in the cinema environment works much the same way - the rendering engine is making assumptions about speaker placement, assumptions based on Dolby guidelines. Presumably if a theater designed an Atmos auditorium with 64 speakers, but scattered them randomly around the room, Dolby would simply say no, not gonna certify that as an Atmos system.

In other words, the speaker remapping that many people are lamenting the absence of was never a part of the system to begin with.
That's what I was afraid was being said by FilmMixer. Looking back at his posts I can see he was trying to tell people this all along. Doesn't seem probable, to me at least, that future generations would include a whole new set of code aimed at actual "remapping." Frankly, I had gotten the impression from some here that such a "feature" was missing only because of processing limitations of current chips. Seems there was a lot of misunderstanding about Atmos all around.
 
#932 ·
In other words, the speaker remapping that many people are lamenting the absence of was never a part of the system to begin with.
Not speaker re-mapping, like what Trinnov does, just mapping channels and objects to actual speaker locations. Are you saying that the theatrical version of Atmos doesn't render to measured speaker locations but instead has pre-defined locations that theatre owners have to conform the speakers placement to? And here I thought that was a limitation of the initial home version.
 
#933 ·
Not speaker re-mapping, like what Trinnov does, just mapping channels and objects to actual speaker locations.
Do we know how mapping for channel-based content will work?

Are you saying that the theatrical version of Atmos doesn't render to measured speaker locations but instead has pre-defined locations that theatre owners have to conform the speakers placement to? And here I thought that was a limitation of the initial home version.
Not dschulz but from what I've read, yes channel-based audio post Atmos still has the same requirements as channel-based audio pre Atmos :)
 
#934 ·
Do we know how mapping for channel-based content will work?
Don't know about how the home version will address more speakers than channel beds, but the theatrical system apparently maps channels to only some speakers on the front and side walls, not all speakers (some are for objects only).
Not dschulz but from what I've read, yes channel-based audio post Atmos still has the same requirements as channel-based audio pre Atmos :)
My question wasn't limited to channels.
 
#936 ·
That's what I was afraid was being said by FilmMixer. Looking back at his posts I can see he was trying to tell people this all along. Doesn't seem probable, to me at least, that future generations would include a whole new set of code aimed at actual "remapping." Frankly, I had gotten the impression from some here that such a "feature" was missing only because of processing limitations of current chips. Seems there was a lot of misunderstanding about Atmos all around.
Interesting; since in the end the sound, object-based or not, is still reproduced by speakers in fixed locations, I suppose there's no reason to have expected Dolby to be more demanding of actual vs. recommended speaker locations.
 
#937 · (Edited)
Not speaker re-mapping, like what Trinnov does, just mapping channels and objects to actual speaker locations. Are you saying that the theatrical version of Atmos doesn't render to measured speaker locations.....
No... it does... the RMU and 850 will accurately render objects to the available speakers based on the room configuration file for each room, and the uses the positional metadata to accuracy place the sound where intended in relation to the center of the room.

.... but instead has pre-defined locations that theatre owners have to conform the speakers placement to?
Yes.. Dolby has specifications for where you should place and install speakers in a theater for what they consider optimal playback of an Atmos mix... and won't certify the theater, or sell you a CP-850, unless they approve the design and installation. For better or worse that's the model they chose...

I appreciate it because I've now heard Atmos in 11 different venues and the experience has been fairly consistent.

Realistically in a majority of situations, the variance in theater design is low.... Some are wider, taller or longer... but almost all are rectangular or squarish in shape and can be counted on to conform to the proper playback of 5.1 and 7.1 channel based mixes.

It's a fairly common denominator.

So when you rely on 5 or 7 speakers to create a 360 degree sound field from both channels and object, I don't know how much flexibility can be expected to still get really stable imaging without creating a tiny sweet spot...

The kind of processing to move the audio into the proper positions based on measured information about where the speakers actually are does appear to be absent in these first products... is that true for all of these upcoming AVR's? I don't know.

If it is, is that coming down the road for 5.1 and 7.1 setups?

That's the question... and when >7.1 processors become available and the number of available speakers exceeds the number of channels in the bed (7 in this case) they are going to have to have tools to properly calibrate multiple speakers being used as surrounds (i.e. playback of beds vs. objects...)

For us, and because you have many more array speakers in a theater setting, you can adjust how you want to present the bed arrays in the 850/RMU.

We will also have to wait and see how this is integrated into these first avr's that support 9.1.2....

Even without it today in the home, I can assume that level trims and delays will compensate for a great deal of variance in most rooms...

This might be something Dan and Roger would have much more insight into... I'm purely thinking of it coming from "my world..."

Not an expert on these matters, and definitely not as well versed as you on acoustics and the like.
 
#938 ·
I am in the middle of wiring my HT in a 9.2 set up. Considering the room is wide open, would you wire the room for 9.2.4? The wire is no big deal. (4) more backer boxes is really the only work involved.
 
#939 ·
I still can't believe we don't have real time monitoring from any avr manufacturer.
I'd happily throw in 2/3/4 mic's to gain that last 1% of SQ.

I'd also like to use it to controll an absolute volume cap. I dread turning down the kids movies when I leave the room, if there was a cap I'd be all over it.

Guess its time to turn/adjust the dynamic range to normal. Might be for the best anyways.
 
#940 ·
I am in the middle of wiring my HT in a 9.2 set up. Considering the room is wide open, would you wire the room for 9.2.4? The wire is no big deal. (4) more backer boxes is really the only work involved.
Definitely!

Way easier to do it now than later - I'd even think of 11.2.4, just in case......
 
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