Rear height placement to work with Auro 3D and Atmos

[Dj7675]

Atmos isn't a mess. Dolby has been consistent about their overhead speaker placement since Atmos was released to the public. They have been as consistent about their speaker setup as Auro has been about theirs.

That overhead spec conforms with how an Atmos studio with a 7.1.4 monitoring system is to be set up. This ensures some sort of conformity between the production and reproduction of the content.

It is always nice to hear from something that does this for a living to get their perspective. In your setup(s) do you follow the Atmos Studio guidlines. Reading through them, they seem to have different/more specific guidlines. Hopefully this is related enough to this thread in regards to atmos placement…

 

[hemiutut]

 

[DutchJay]

Thanks, great video!

 

[napfkuchen]

This will be very helpful for setting up height speakers, thank you!

 

[wseroyer]

This video is such bad advice, Dolby's system is very different in how it processes sound from AURO's. Set the Speakers up at the 45 degree angle 30 degrees apart from each other if you doing a Atmos system.

 

[napfkuchen]

This video is such bad advice, Dolby's system is very different in how it processes sound from AURO's. Set the Speakers up at the 45 degree angle 30 degrees apart from each other if you doing a Atmos system.

For me his explanations were quite convincing. Also according to this comprehensive guide 45° angles will result in the sound losing "[...] its vertical coherence which means that the sound coming from the two speakers [meaning ground layer and height layer] are perceived as two different sources, even if there is a natural coherence in the source material". In my living room 30° is easily achievable, I also plan on using an AVR with Auro 3D upmixing ability to (hopefully) have the best of both - Atmos and Auro 3D - worlds. In the end it all comes down to compromises, at least for us poor peasants without dedicated home cinemas.

 

[hemiutut]

This video is such bad advice, Dolby's system is very different in how it processes sound from AURO's. Set the Speakers up at the 45 degree angle 30 degrees apart from each other if you doing a Atmos system.

If that video is bad advice, you can tell him on his YouTube channel since here he surely won't be able to refute it.

Greetings

 

[wseroyer]

If that video is bad advice, you can tell him on his YouTube channel since here he surely won't be able to refute it.

Greetings

I have, and I talk to Channa quite often on live streams and facebook. I've personally tried 30 - 45 - 55 degree set ups, and for atmos I believe that having them a 55 degrees works the best, it has the most convincing sound that stuff is above my head.

I personally am going by Steven Smiths guidelines and they line up best with what I'm hearing, to me 30 degrees just didn't sound good I got almost no height effect they just seemed to make the sound slightly taller, but it didn't have Helicopters above me or anything like that going 45 put objects above me, but they still seemed to be muddied by the front stage 55 degree's is where I got really good channel separation I could really discern things above me.

 

[Reverend Slim]

For me his explanations were quite convincing. Also according to this comprehensive guide 45° angles will result in the sound losing "[...] its vertical coherence which means that the sound coming from the two speakers [meaning ground layer and height layer] are perceived as two different sources, even if there is a natural coherence in the source material". In my living room 30° is easily achievable, I also plan on using an AVR with Auro 3D upmixing ability to (hopefully) have the best of both - Atmos and Auro 3D - worlds. In the end it all comes down to compromises, at least for us poor peasants without dedicated home cinemas.

Except that vertical coherence is an Auro conceit that their underlying tech relies upon, not something Atmos is based around. The heights aren't in-line with the mains in Atmos, so you don't need to worry about the vertical stereo coherence that Auro uses to get good results. Think more vector-based amplitude panning than vertical stereo coherence. An argument can be made for lining up Atmos top front/rear in an arc so you're getting equivalent alignment of the heights and their corresponding adjacent ear-level speakers, which might work better in a home space... but isn't something taken into consideration in a theatrical space. We generally don't start losing sense of elevation steering between speakers until about 50-60 degrees, and we don't hear elevation on the vertical until amplitude is roughly equal between speakers, so a 30 degree placement per Auro can result in a much smaller effective range of precision for sounds between layers (15 degrees vs. about 23 for a stock 45 degree top front/rear placement).

But yeah, it's all about compromises. If you want to support Auro, they have a much narrower window for placement which won't be ideal for Atmos but will certainly work. If you disregard Auro, placement per Dolby's mix room standards (or planned using Dolby's Atmos room design tool) is ideal. Likewise, if you're better at hearing elevation than overhead, you may prefer the Auro-style layout anyway. If you're better at hearing overhead, a tighter spacing (like the aforementioned 55 degrees) of the heights may give you better results. The 45 degree top front/rear is meant to strike a reasonable balance between the two.

 

[just1n]

Nah, the poster above is correct. That's what it shows -- and it will use the front heights for Atmos, but it will not use Surround Heights for Atmos, only Rears. I've tested it, you don't get audio out of them.

Considering that Auro3D is almost exclusively used for upmixing, this means you should just run your heights as Rear Heights regardless of their positioning. There is really not much, if any, difference in the upmixed output for those channels, but the Atmos sound field is improved significantly by having the extra 2 height channels.

In your case, the speakers will be behind the listeners anyways so I would put them high up on the walls and set them as Rear Heights for sure.

While preparing to add 4 height speakers to my setup I found this thread because I’m eager to try upmixing for stereo content. I checked the Denon X3800h manual just now and found something that may be different. Looks like you can now set the speakers to surround heights since the March 2023 firmware update, too.

Changes to the speakers compatible with Dolby Atmos and Auro-3D playback

manuals.denon.com

Maybe it was brought up in this thread and I haven’t gotten to the post yet. Apologies if it has and this is know information.

 

[sarumbear]

Hi all,

I am just looking for some advice. I'm going through quite a few changes to my setup, I got an Arendal 1723S center channel coming in soon and in few days will have Denon X4700H. I am working towards a full Atmos 5.2.4 / Auro 3D 9.1 set-up.

As far as the front goes I think everything is fine and meets both the Auro 3D and Atmos requirements:

However I am not sure what to do when it comes to the back.
As sadly I do not have much space at all, since there is window and radiator. The sofa is already 20" from the back wall and can't move it any further into the room:

For a simple Atmos set-up I could just place speakers right above on the ceiling (red) pointing down BUT that will not work properly with Auro 3D, so I'm wondering if placing speakers on the walls angled down just above the surrounds (blue) would work for both?

Any advice highly appreciated

My suggestion would be ignore Auro 3D and setup for Atmos 5.1.4 which will fit to your room well.

5.1.4 Overhead Speaker Setup

Learn how to set up Dolby Atmos 5.1.4 overhead speakers for an immersive Dolby Atmos experience. Get professional tips and guidance for optimal speaker placement.

www.dolby.com

Unfortunately, Auro 3D has no future. They are still in bankruptcy; you will not find many films that comes with only Auro 3D soundtracks. I had a combined Auro 3D / Atmos layout managed by a Trinnov Altitude-16 but after never once heard any sound coming from the God channel or the front heights (on the films that offered Auro 3D soundtracks) I changed my setup to Atmos only.

 

[keenly]

Set up Atmos, and listen to Auro that way, I do. I have about 10 Auro 3D music blu rays, some also have atmos mixes. The Atmos and Auro mixes are always identical, thus an atmos set up is fine.

 

[Nyanko]

Hi, I need some help to get my RH speakers position right for AURO 3D. Auro guideline is based on angles (between 25 and 40 degrees) to get a Bed and Heigh Layer. I've drawn a cone in the LP with both limit angles to have an idea of the "recommended area" to install the speakers. Later I projected the cone into a parallel plane to get the cut edges of it and define the area that may contain the speakers (yellow lines in the draft). As you can see the LP is farther away from the front speakers than the rear speakers and it forces me to install the rear speakers at a lower elevation than the front ones in order to keep the angles in range. The obvious consequence is that the height layer is not parallel anymore to the bed layer. The area in back of the LP is compressed compared to the area in the front of it. My questions are: (1) Should I prioritize angles (back speaker at lower position) or layers parallelism and separation (back speakers at higher position but out of angle)? If the bed layer and the top layer are not parallel planes then will this affect the perceived dome of sound and sound source location? In which way? Thanks a lot.