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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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#3,802 ·
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.

If there really is "Atmos Secret Speaker Sauce" in the speakers--rather than say just clever acoustic throw+focus technology to accommodate the distance from transducer to MLP, and "via ceiling" bounce--then the question becomes: Will there be a problem using these same add-on Atmos speakers with a DTS-UHD decoder in your next AVR? or similarly with an Auro-3D decoder?
_
 
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#3,803 · (Edited)
I got the chance to attend the Dolby Labs Home Atmos demo yesterday.

I went in with the idea that the ceiling mounted speakers were going to be the better sounding option..but after listening to the demos and switching back and forth...I preferred the Dolby Atmos Enabled speakers over the ceiling mounted. I felt that the Dolby Atmos Enabled speakers sounded like a larger over head space and just more enveloping to me.

I was able to take some pictures of the demo room we were in ... I will be posting those later today.
That I can understand. As NorthSky explained it, beaming upwards effectively quadruples (2 x as wide and 2 x as deep) the surface covered by the speakers vs ceiling mounted.

But that is not all what Atmos is about. It is also about up to 128 sound objects being precisely rendered in the hemisphere. if that object is large, like a car or a plane, then the upwards will work. But I think a Robin in the woods could sound so "enveloping" that it's more like the size of a Turkey, no? ;) So, that's one concern.

There's a second concern: no way are the ceilings in my HT going to be as flat and shiny as in that Hong Kong demo here: https://www.facebook.com/RickyChanw...10152634741779188.1073742091.783714187&type=1

Also traditional 2-way speakers are probably not ideal, as we discussed here before. Please post those pics, so we can see.

So, the question is what will give the best overall sound quality? Upward firing 30 watt capable add-on speakers in a space with untreated ceilings? Or ceiling mounted 300 watt coaxials with a fully acoustic treated ceiling? BTW, the ceiling is by far the ideal spot to treat, as it is large, we don't walk on it (except you, Lionel Richie) and we don't hang paintings on it...
 
#3,804 ·
Is that information provided by Dolby?
Yes, they told us yesterday that height modules could be placed close to the speakers rather than directly on top.

On a related note, there is a 3rd white paper coming out that is intended as an installation guide with best practices for custom installers (and the rest of us) that Dolby intends to release at CEDIA.

Personally, I would hold off on mounting any speakers until I've at least perused that white paper. At that point, I would decide how closely I want to stick to their recommendations.
 
#3,805 ·
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


Is that information provided by Dolby?
I also read this on the Onkyo web site in the description of the atmos modular speakers.
 
#3,806 ·
Yes, they told us yesterday that height modules could be placed close to the speakers rather than directly on top.

On a related note, there is a 3rd white paper coming out that is intended as an installation guide with best practices for custom installers (and the rest of us) that Dolby intends to release at CEDIA.

Personally, I would hold off on mounting any speakers until I've at least perused that white paper. At that point, I would decide how closely I want to stick to their recommendations.
Thanks, will wait.
 
#3,807 ·
Is that information provided by Dolby?
Yes - they can be up to 3 feet away from the main speakers they relate to.

From the Dolby Atmos FAQ:

"You can place these add-on modules on top of your current speakers or on another nearby surface.

"If you’re using add-on modules, place them either on top of your front and surround (ideally, rear surround) speakers or within 3 feet (0.9 meter) of those speakers."
 
#3,808 ·
#3,810 ·
But that is not all what Atmos is about. It is also about up to 128 sound objects being precisely rendered in the hemisphere. if that object is large, like a car or a plane, then the upwards will work.
That's what Atmos is all about for you, but not necessarily for others. I've heard imaging so precise, it made a singer appear to have a head the size of a golf ball. Yeah, it was pinpoint, but unrealistic.

Same with the Atmos demo yesterday. Instead of 4 precise spots overhead, the upward firing drivers sounded more like a seamless ring above the listening area. Part of the problem might have been that the 4 Tannoys mounted overhead were pointing straight down. How much better would they have sounded had they been toed in, even cross toed to the person furthest away (energy trading)? We'll never know.
So, the question is what will give the best overall sound quality? Upward firing 30 watt capable add-on speakers in a space with untreated ceilings? Or ceiling mounted 300 watt coaxials with a fully acoustic treated ceiling?
You left out the part where the upward firing speaker had its driver sliced up and was connected with 24 gauge lamp cord.
 
#3,812 · (Edited)
I got the chance to attend the Dolby Labs Home Atmos demo yesterday.
Looks like FilmMixer and sdurani have pretty much touched on most of what we saw and heard, and the only thing I can really add is my personal opinion.

I went in with the idea that the ceiling mounted speakers were going to be the better sounding option..but after listening to the demos and switching back and forth...I preferred the Dolby Atmos Enabled speakers over the ceiling mounted. I felt that the Dolby Atmos Enabled speakers sounded like a larger over head space and just more enveloping to me.

I was able to take some pictures of the demo room we were in ... I will be posting those later today.

Sorry to have such a brief writeup..but FilmMixer and sdurani have pretty much covered the better part of the technical aspects.

Just my $.02
RayJr
This, is the most interesting post so far. ...I will be monitoring very closely all the developments, because me too I want the very best surround envelopment. And in my room with cathedral ceilings this is great news as it is much more simpler. ...Installation and all.
And even if I would have the perfect reflective ceiling @ 9 feet, I would still go with floor up-firing Dolby Atmos speakers @ this point.

I love the simplicity of it all for home. ...Simply add four small Dolby Atmos satellite (coaxial) speakers atop your two front mains and two rear surrounds (in a 7.1-ch setup), and aim them properly (a la Andrew Jones), connect them to your new unit, et voila. ...No holes, no complication, no ladder, no wires concealment to take care of, just like normal surround business with wires on the floor alongside the walls, or under the floor. ...The ceiling remains as it is, the wife is happy, and the surround effect is greater. ...A win-it-all situation.

I love this idea so much much much more, and I am so happy of what people have found so far, like you just said it above. Thank you, you made my day. ...Now, waiting for DTS-UHD ,,, :)
 
#3,813 ·
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?
Or a variation on a Mirage Omnipolar with a coldspot on axis.
 
#3,814 ·
#3,815 ·
I'd like to take a moment to thank the "heavy lifters and thinkers" here for pushing the envelope wrt to "understanding" D: All of the above


I went ahead with the overhead trestle project , it penciled out to only about $100 because I already had most of the stuff (dude, you got WAY TOO MUCH STUFF)!), the time and patience and wanted to follow thru on the discussion I had had with Sanjay.


The attached picture is the "on ceiling" thing. there is no speaker attached, obviously,
My measurements from the center of that bracket to which the SLX attaches to the center of the speaker to the right or behind is about 88 inches, and subtracting for the 4" depth of the speaker puts all four in about a 7 foot square wrt to MLP. (42" ahead, behind, left and right)
The angle "up' is about 35 degrees or less.
The distance from the TF's to the plane of the LCR is also about 80 inches, so using the 35-50 degree option for repositioning of the FH's, there's room for the other 2 SLX sitting around, could also be hung horizontally. think 9.x.4
WRT to the vertical/horizontal argument, I think that for my one-man gets his own MLP theory (?), the notion mentioned earlier about "walking in a circle" to hear the sound change is an interesting possibility. But what if I could just sit there and get that effect and a few others . . . yeah baby, lock and load . . . in the money seat . .
I'll run the wires and will make them all equal length, about 40 ft max if I go up thru the wall and across the attic, it needs some more pencil work . . .So...
Any suggestions about how to deploy/experiment with/enjoy
this set up while we wait? I have an extra amp that will let me do another 6 channels of amplification


p.s. Everything is Rustoleum 2X satin "Granite" and mostly matches the speaker color and is near invisible in extreme low light/darkness.


And a box holing the "right" co-axial is not out of the question


standing by


and one more time
TY
 

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#3,816 · (Edited)
While most of you will be drilling holes in your ceiling, and playing with harnessing the wiring,
me I'll be putting some blu tack atop four of my speakers (lucky me they are flat on top - all four are 44" high - perfect height, I think - because I won't be hearing sound coming directly from them - my ears are @ 33" height). ...And my ceiling is all made of perfect reflective wood surface to expand that Dolby Spatial sauce.
...Starting @ 8.25 feet @ the walls and up to 11.0 feet @ center. ...I feel I have the ideal room to retire in higher "elevation".

Man I love this hobby! ...Do you too?
 
#3,817 · (Edited)
How do you EQ speakers that are designed to bounce the audio off of the ceiling over a wide area?
I guess we don't.

And the AVR (SSP) would know how far they are from the ceiling, and the main listening position.
From that the receiver would know what just to do with its Auto Room Correction & EQ system as implemented by its manufacturer and working in tandem with the Dolby Atmos chip decoder.

My best guess is that they won't be massaged/EQued as they are already designed with a 180Hz crossover and Dolby Atmos spatial effects going through them.

But my guess could be proven wrong; if some expert is in the know. ...Because they could be EQued as well to give that ideal target curve with that upper tilt in the bass and gently descending towards the treble region for that desired smooth sound that all of us aspire to.

Who's going to be good @ it best? ...Audyssey? ...AccuEQ? ...MCACC? ...YPAO?
...Datasat? ...Trinnov Altitude? ...Dirac Live (Amarra - Audirvana)? ...Room Perfect? ...XTZ? ...ARC? ...Acourate? ...Audiolense? ...jriver? ...And there are many more...(but the first four above are the main ones which we are concerned with so far @ this point in time.)

And each year they will implement further improvements to their bass management system and all.
EQ is a perpetual work in progress; science is improvement, not rules.
 
#3,819 ·
#3,820 ·
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?
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?
♦ Touche.
 
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