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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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#3,781 ·
Timbre matching was really important back in the day. Now we have EQ...

EDIT: LOL. I see I was comprehensively beaten to it by others. But yes, timbre matching was important when we didn’t have EQ at home. But those days are long gone and we can now EQ our speakers to bring them into tonal balance with each other.


How do you EQ speakers that are designed to bounce the audio off of the ceiling over a wide area?
 
#3,782 ·
Why not see what the manufacturers of your current speakers are going to do in answering the needs of the Atmos format?
My speakers are all M&K or the later MK Sound versions (S150 LCR and M7 surrounds). It is highly unlikely that MK would introduce a coaxial speaker, (my preferred design for ceiling speakers for reasons recently stated) as this would be totally out of line with the design concepts which have been M&K's hallmark for decades. Nothing is impossible of course, but to wait would possibly mean waiting for years.

And given that I am a firm believer that EQ can address tonal differences very well indeed, and certainly well enough for the beneficent incorporation of surround speakers into a system (which is what the Atmos speakers are, really), then I am not concerned with timbre matching for now.
 
#3,783 ·
How do you EQ speakers that are designed to bounce the audio off of the ceiling over a wide area?
I won't be using speakers that bounce the audio off the ceiling, so it is of no concern to me how they would be EQd.

Surely my earlier posts made it clear what kind of speakers I will be using, even down the the model name and number and a provided link to the manufacturer's web site?
 
#3,784 ·
Speaking more genericaly about EQing bounced audio, I think we'll just have to wait to find out how well it's handled. To a certain extent, I'd expect it to depend on the design of the Atmos-enabled speakers. So long as the mic can't detect a significant amount of direct sound from them, I'd expect it to work just as well for the reflected audio coming from the Atmos-enabled speakers as it does for the direct audio from the other speakers.
 
#3,785 ·
I won't be using speakers that bounce the audio off the ceiling, so it is of no concern to me how they would be EQd.

Surely my earlier posts made it clear what kind of speakers I will be using, even down the the model name and number and a provided link to the manufacturer's web site?


Instead of the self centered "you", how about the more general "you", meaning those who will use speakers that bounce the audio off of the ceiling?
 
#3,787 ·
Here was the only picture I could find which demonstrates the effect:



So, as along as the on-ceiling tweeter/woofer speakers are mounted upright, what would be the other mounting considerations?
Is this a picture of two different speakers? If not, I don't understand how this works. If gravity is not involved how would rotating the speaker 90 degrees suddenly change the radiation.

I mounted Boston Voyager speakers. These are speakers with two drivers and the owners manual shows them mounted sideways. I did mount them so the Low would point to the wall and the tweet points to the center away from the closest wall. While testing the speakers i could really hear no difference while changing the speakers position. I do understand that a speaker is best placed for what it was designed for but I don't understand how lobing can be introduced when a speaker is rotated. If it really is an issue, than it would also make a difference where one is seated in relation to a single two way ceiling speaker. People sitting more to the left from the rear left ceiling speaker that is mounted 90 degrees of its designed position should hear a different sound than people seated right of that same speaker. I will do some more hearing tests later on to confirm or deny this in real life (not in theory) in my own theater. I can see how mounting the speaker in it's designed position would not introduce this problem.

If it turns out to be a huge difference in hearing experience, I can Always buy new speakers:D
I did go for those so that I atleast didn't have Timbre matching issues.
 
#3,789 ·
It doesn't change the radiation, only whether the radiation anomalies are perceived. If you mount the speaker vertically, and assuming your seated listening height doesn't change vertically, you will hear the same sound as you move left to right in the seating area. If you mount the speaker horizontally, the sound will change as you move left to right in the seating area. This is due to having the same sounds coming from two different drivers whose distances to the various seating positions, relative to each other, change.

If you mount the speaker vertically, and if you have people sitting with ear heights at 2', 4' and 6', you will have the same problem. That's just not very common though (although different rows of seating would be somewhat affected).
 
#3,790 ·
It doesn't change the radiation, only whether the radiation anomalies are perceived. If you mount the speaker vertically, and assuming your seated listening height doesn't change vertically, you will hear the same sound as you move left to right in the seating area. If you mount the speaker horizontally, the sound will change as you move left to right in the seating area. This is due to having the same sounds coming from two different drivers whose distances to the various seating positions, relative to each other, change.

If you mount the speaker vertically, and if you have people sitting with ear heights at 2', 4' and 6', you will have the same problem. That's just not very common though (although different rows of seating would be somewhat affected).
OK, I understand it correctly than. I do however change my ear height to the speakers because my seats can be in an upward or a realx position. Right now it doesn't really matter where you sit. All seats appear to sound the same after I introduced Audyssey in 2010. The Boston Voyagers are relatively small speakers so the distance between the two drivers is not very big. By mounting them the way I did, I can angle the speakers toward the seats whereas I could not have done that any other way while using the same mounting brackets. So I am probably a bit off of perfect but by looking at my sistuation, it is a still a good solution. My ceiling could host in ceiling speakers but I would have to invest a lot of time to make them custom fit which by the way is a nice way to spend time.. If I am not blown away in october after installing the Denon 5200 I will start my search for another solution. Right now I am ready to install and start testing which could be in a few weeks already because Onkyo still wants to come and prove their AccuEQ against Audyssey in my theater.
 
#3,791 ·
Instead of the self centered "you", how about the more general "you", meaning those who will use speakers that bounce the audio off of the ceiling?
I assumed that as you were replying to me, and not asking a general question of the thread, that you were in fact addressing, well, me. How silly of me.
 
#3,792 ·
Is this a picture of two different speakers? If not, I don't understand how this works. If gravity is not involved how would rotating the speaker 90 degrees suddenly change the radiation.
The dispersion pattern of the speaker will change in relation to your ears when you rotate it (or you for that matter).
 
#3,793 ·
The dispersion pattern of the speaker will change in relation to your ears when you rotate it (or you for that matter).
Walking in circles underneath my ceiling speakers is also going to be very easy to test if only I were home from holiday:cool: In all of these cases (speaker higher or lower, orientation etc) I am not so interested in the theory. I can understand why one thing is better than the orher but I am interested in how it sounds like after a good calibration. Knowing that it could probably sound even better when done right but right would costs aesthetics or time and obviously money.
Many things to do next saturday..
 
#3,794 · (Edited)
Interesting feedback from the Burbank Dolby demo regarding their preference of Atmos enabled front/rear speakers over the ceiling installed height speakers. This surprised me since everything I've ready from Dolby has stated that the sweet spot for home Atmos is having 4 ceiling speakers installed.

Since all agreed that the reflecting sound from the Atmos enabled speakers produced a more enveloping 3d sound field than direct firing ceiling speakers, wouldn't bipole/dipole ceiling speakers be the trick for creating this similar type enveloping 3d sound field? Even if you use min 90 degree dispersion monos, a diffused omni-directional bi or di pole should do the trick better, right?
 
#3,795 ·
Walking in circles underneath my ceiling speakers is also going to be very easy to test if only I were home from holiday:cool: In all of these cases (speaker higher or lower, orientation etc) I am not so interested in the theory. I can understand why one thing is better than the orher but I am interested in how it sounds like after a good calibration. Knowing that it could probably sound even better when done right but right would costs aesthetics or time and obviously money.
Many things to do next saturday..
I wonder if you walk around the room during an atmos movie you could actually pinpoint the location of the sounds...like if you heard something in the center of the room, would you be able to walk around it? If you were on the right side of the room, the sound would come from the left of you, and if you were on the left side of the room, the sound would be on your right.
 
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#3,796 ·
I wonder if you walk around the room during an atmos movie you could actually pinpoint the location of the sounds...like if you heard something in the center of the room, would you be able to walk around it? If you were on the right side of the room, the sound would come from the left of you, and if you were on the left side of the room, the sound would be on your right.
No, Atmos does not reconstruct a wave field, it is based on stereo instead.
 
#3,797 ·
Is it possible some of you, in your understandable enthusiasm, are jumping the gun by purchasing new, mis-matched speakers right now?

Why not see what the manufacturers of your current speakers are going to do in answering the needs of the Atmos format?

There is a little something called timbre matching that would probably be a lot more critical with object based surround. ;)


That's exactly what's going through my head, you seem to be the fist one on here to mention it :wink:
 
#3,798 ·
Is it possible some of you, in your understandable enthusiasm, are jumping the gun by purchasing new, mis-matched speakers right now?

Why not see what the manufacturers of your current speakers are going to do in answering the needs of the Atmos format?

There is a little something called timbre matching that would probably be a lot more critical with object based surround. ;)
No, that's why I want a pair of add-on atmos speakers opened up and any component network deconstructed... So I can add the same function to a timbre-matched speaker of my choice. (Or if there isn't any components at all - to know that.)
 
#3,799 ·
No, that's why I want a pair of add-on atmos speakers opened up and any component network deconstructed... So I can add the same function to a timbre-matched speaker of my choice. (Or if there isn't any components at all - to know that.)
A little bit of reverse engineering to see some of Dolby's "secret speaker sauce" (sans added post processing). :) Not a bad idea at all.
 
#3,800 ·
So we can keep our speakers Sanjay and use external speakers ( modules )?
Sure, no one has ever said otherwise. And height modules don't have to be physically placed on top of your current speakers, as long as they hit the correct location on the ceiling.
Another question is if I have heights already can I angle them towards the ceiling ?
Aren't they already on the ceiling?
 
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