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Straight does play ATMOS. Receiver shows it and also if I mute floor speakers, I can hear sound coming from ceiling. Issue isn't with sound not coming. It has to do with how loud it comes.

I have an RX-A3040 and when I put it to STRAIGHT I 1005 definitely lose my overhead speakers - maybe my unit is faulty ??
I know the HDMI board is faulty as some inputs and one output doesn't work but I wouldn't think that would affect the sound modes in that way ?



 

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Source is not Atmos.

Source is definitely Atmos. I have also just noticed that in DSU mode all the speakers are showing on the display panel but it only plays in stereo but only when playing YouTube from my Xbox - all other stereo source upmix OK :confused:


My HDMI board is faulty with a couple of inputs and one output not working and occasionally it completely locks up and I have to do a master reset. So assuming that is also causing these other problems it looks like I have no choice but to replace my HDMI board - for a mere $750AUD plus labour to install:mad:





 

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Unfortunately you cannot activate SS1 and SS2 without first activating Side Surrounds (they are prerequisites, just like Front L/R are prerequisites for activating the Centre speaker). SS1 and SS2 do not get any channel information, only object info.
I would think Rear Surrounds couldn't be possible without Side Surrouds either, but 5.1 + FW does sort of work that way.

I offcourse have no experience with a Trinnov, but I thought with it's speaker remapping tools it may be possible to create a virtual Side Surround in between two real Side Surround speakers. That way they would both play the Side Surround bed and object content, but still might play they're own object information individually.
 

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I would think Rear Surrounds couldn't be possible without Side Surrouds either, but 5.1 + FW does sort of work that way.
The fact that the rear surround channels are combined with the side surrounds channels to create the surround feeds of a 5.1 config, doesn't make those surround speakers suddenly rear surround speakers. It's true that the home Atmos decoder also copies surround info to the wides in a 5.1+wides config, but that info is not completely removed from the surrounds.

I offcourse have no experience with a Trinnov, but I thought with it's speaker remapping tools it may be possible to create a virtual Side Surround in between two real Side Surround speakers. That way they would both play the Side Surround bed and object content, but still might play they're own object information individually.
That is correct. If you have three pairs of side surround speakers assigned to respectively SS1, SS, and SS2, you can subsequently physically reposition the SS speakers to a very different location, and the remapping function of the Altitude will try and create a virtual SS speaker in-between SS1 and SS2, using predominantly those two speakers.

PS If you would put the SS speakers at locations where you do not expect they will used by the remapping function (e.g. below the listeners' level), you could in theory physically remove them from your room after the calibration and optimization (a process during which the Altitude needs to "see" them).

It might be an interesting suggestion for those with an Altitude that are employing two pairs of side surround speakers, and do not mind using two extra outputs on their processor for this 'trick'. :)
 

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The fact that the rear surround channels are combined with the side surrounds channels to create the surround feeds of a 5.1 config, doesn't make those surround speakers suddenly rear surround speakers. It's true that the home Atmos decoder also copies surround info to the wides in a 5.1+wides config, but that info is not completely removed from the surrounds.
Exactly. The side surround is thereby in fact phantomed betweed the wides and surround speakers.

That is correct. If you have three pairs of side surround speakers assigned to respectively SS1, SS, and SS2, you can subsequently physically reposition the SS speakers to a very different location, and the remapping function of the Altitude will try and create a virtual SS speaker in-between SS1 and SS2, using predominantly those two speakers.
Which would create a side surround array of two speakers right?
 

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I thought Atmos Wides were only used for objects, and that what you describe above pertains to the DTS NeuralX upmixer.
An Atmos speaker layout with 5.1+Wides in the base layer will send object audio to the Wide speakers and Rear channel audio to the Surround speakers while Side channel audio will be split to the Wide speakers & Surround speakers (causing it to phantom image at your sides, where the Side speakers would have been in a traditional 7.1 layout). This is part of the native remapping that happens during Atmos decoding.
 

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I thought Atmos Wides were only used for objects, and that what you describe above pertains to the DTS NeuralX upmixer.
No, as Sanjay described the situation changes when you drop the back surrounds. The renderer now assumes the Surrounds are further back (not 90 degrees but ~120 deg AFAIK) so objects at Y=0.5 (90 deg) will be phantomed between adjacent speakers (surround + wide). Remember what we've learned recently that even the "beds" are converted into objects as part of spatial coding, they become "static" objects with fixed cardinal coordinates (Y=0.5 for side surrounds) so the renderer will reproduce the audio signal for that "bed" with the available speakers based on the object metadata, vs. locking them to a single "channel" output.
 

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I'm looking for advice on placing ATMOS ceiling speakers. The attached diagram shows current speaker placement and seating. The two MLP positions are the most important. Sometimes I use the center SLP seat for a 1.85 movie, but I'm not too worried about the front row. I think I'll be doing 4 ceiling speakers, but possibly 6. If I do 6, I'm assuming that two would go above or in front of the front row, which would then require rethinking the ceiling sound absortion, but that is doable. I'm also wondering about moving the two rear speakers closer to the center. There is a window between them now, but I have finally gotten WAF approval to remove that, so I have the opportunity do it at that time, and would like opinions on whether that's worth doing. Thanks.
 

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I have asked Trinnov about the feasibility of this arraying beds, and their answer is clear and conclusive. In short: Arraying of bed channels is not possible with consumer Atmos. This is not a limitation of the decoder but of the way it is encoded. The spatial coding mechanism merges bed and objects into dynamic objects. There is no way to differentiate one from the other from the encoded content, the information simply is lost.
According to Cortex VIP Cinemas, the Dolby CP850C will array the bed channels for consumer Atmos. I am not clear on how this is accomplished, and I haven't yet seen anything official from Dolby on the 850C. Has anyone seen an 850C in the wild, or know of anyone installing them apart from Cortex?
 

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I'm looking for advice on placing ATMOS ceiling speakers. The attached diagram shows current speaker placement and seating. The two MLP positions are the most important. Sometimes I use the center SLP seat for a 1.85 movie, but I'm not too worried about the front row. I think I'll be doing 4 ceiling speakers, but possibly 6. If I do 6, I'm assuming that two would go above or in front of the front row, which would then require rethinking the ceiling sound absortion, but that is doable. I'm also wondering about moving the two rear speakers closer to the center. There is a window between them now, but I have finally gotten WAF approval to remove that, so I have the opportunity do it at that time, and would like opinions on whether that's worth doing. Thanks.

I have six Atmos speakers which I believe is overkill and my room is a bit longer than yours.

Based on my experiments and in my room with 9.5’ ceilings I would recommend that you use two rows with the front row very slightly (two feet maximum) in front of the MLP. My front row of ceiling speakers is based on Dolby recommendations and is too close to the LCR even though it is still 8’ 10” from LCR. My ceiling speakers are not angled toward the MLP but they are controlled dispersion Procella speakers with an 80 degree high frequency coaxial driver and waveguide.

What happens is that if just the front row is engaged the sound gets lost in the LCR.

So I placed my middle row right over the MLP and those are the ones I feel give me the best envelopment.
Terrible pic of my middle and front row Atmos ceiling speakers:




Sent from my iPhone using Tapatalk Pro
 

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According to Cortex VIP Cinemas, the Dolby CP850C will array the bed channels for consumer Atmos. I am not clear on how this is accomplished, and I haven't yet seen anything official from Dolby on the 850C. Has anyone seen an 850C in the wild, or know of anyone installing them apart from Cortex?

Cortex was making similar claims at CEDIA and saying the 850C did something "special" that no other Atmos processor was able to do for consumer home Atmos tracks. I don't know if they're confused about the product or if they know something Dolby is not readily divulging (I noticed too many marketers and industry reps at the expo were ill informed about their own products, especially since the bulk are just US reps or distributors and the products are made by foreign companies - so take it as you will).
 

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I don't know if they're confused about the product or if they know something Dolby is not readily divulging.
Confused probably. It surely is possible to array selected audio sub-streams over multiple speakers, while keeping those speakers individually addressable for other sub streams, whether being single objects or spatial coded clusters. But, if such selected audio sub-stream happens to be a cluster itself (e.g. containing original cinematic bed channel info + one or more original cinematic objects), the whole cluster will be spread over the speaker array. The home Atmos encode simple contains no metadata to “dissect” a spatial encoded cluster into its separate components. And while @Roger Dressler believes that theoretically there might be sufficient bread crumbs in the bitstream to let a new renderer implementation do just that, software engineers at Trinnov have seriously been looking for them and concluded that they are just not there ...
 

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With reference to the diagram we have seen before
the 4th substream does indeed carry audio essence plus metadata when we're talking about Blu-ray (TrueHD) coded audio or MAT 2.0.

I would like to thank you for this note. Of course each TrueHD sub-stream includes audio signal. But I woudl like to check it in another side
1). This diagram above is a little bit incorrect. In accordance with classic TrueHD structure the main sub-stream should be full stereo downmix 2.0 (not 5.1). Decoder reconstructs 5.1 from the main stereo downmix 2.0 plus the 3.1 channel extension A (re-matrixing). The same for 7.1 - the decoder uses the reconstructed 5.1 and reconstructs 7.1 with the next 2.0 channel extension B.


2) In theory the 4th sub-stream (with objects) could be used as next extension for this "re-construct & re-matrixing". And in this case it could be possible to present beds+objects Home Atmos looks like the Cinema Atmos, i.e. to extract the independent beds and objects from the bitstream. But it does not work like that.


I assume that I found the answer in old white paper - Dolby Atmos for the Home Theater, August 2014. This edition is not available at Dolby website (it has modified edition from 2016) but you will find it at http://www.kef.com/uploads/files/en/series_pdf/Dolby-Atmos-for-the-Home-Theater.pdf


Page 13.
Dolby Atmos in Dolby TrueHD
Dolby has extended the Dolby TrueHD format, used in Blu-ray discs, to allow the format to carry Dolby Atmos content. Before Dolby Atmos, Dolby TrueHD included lossless support for channel-based audio, such as 5.1 and 7.1. We have added a fourth substream for Dolby Atmos sound.
This substream represents a losslessly encoded fully object-based mix.




I can interpreter this that 4th sub-stream is totally independent, and includes all 12-16 atmos elements/objects (full mix). As well as old decoder ignores 4th sub-stream, the new Atmos decoder ignores the 3 sub-streams (main mix, extensions A and B) and uses only 4th sub-stream for Atmos playback. Only one problem with this idea, the size of this TrueHD track should be (estimated) 2 times more, but it is not.
 

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Page 13. Dolby Atmos in Dolby TrueHD
Dolby has extended the Dolby TrueHD format, used in Blu-ray discs, to allow the format to carry Dolby Atmos content. Before Dolby Atmos, Dolby TrueHD included lossless support for channel-based audio, such as 5.1 and 7.1. We have added a fourth substream for Dolby Atmos sound.
This substream represents a losslessly encoded fully object-based mix.

I can interpreter this that 4th sub-stream is totally independent, and includes all 12-16 atmos elements/objects (full mix). As well as old decoder ignores 4th sub-stream, the new Atmos decoder ignores the 3 sub-streams (main mix, extensions A and B) and uses only 4th sub-stream for Atmos playback. Only one problem with this idea, the size of this TrueHD track should be (estimated) 2 times more, but it is not.
This size of 4th sub-stream could IMO be reduced by using the reconstructed 7.1 information. That would mean that this 4th sub stream only has to carry the audio objects (including its positional metadata) that are NOT part of the 7 main speaker feeds after the home Atmos decoder has done its work. The information carried by the 4th sub stream is used to extract those audio objects from the 7 main speaker feeds of the 7.1 reconstruct, after which the Atmos decoder repositions those extracted audio objects according to the available Atmos speakers. However, extracting those selected objects from the 7 main speaker feeds does not necessarily recover the cinematic bed channels, as they still contain object information when they are part of a spatial coded cluster.

2) In theory the 4th sub-stream (with objects) could be used as next extension for this "re-construct & re-matrixing". And in this case it could be possible to present beds+objects Home Atmos looks like the Cinema Atmos, i.e. to extract the independent beds and objects from the bitstream. But it does not work like that.
Because of my theory above ... ?
 

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This diagram above is a little bit incorrect. In accordance with classic TrueHD structure the main sub-stream should be full stereo downmix 2.0 (not 5.1). Decoder reconstructs 5.1 from the main stereo downmix 2.0 plus the 3.1 channel extension A (re-matrixing). The same for 7.1 - the decoder uses the reconstructed 5.1 and reconstructs 7.1 with the next 2.0 channel extension B.
You are quite correct. I'm not sure where that diagram originated -- but apparently not Dolby. ;)

2) In theory the 4th sub-stream (with objects) could be used as next extension for this "re-construct & re-matrixing". And in this case it could be possible to present beds+objects Home Atmos looks like the Cinema Atmos, i.e. to extract the independent beds and objects from the bitstream. But it does not work like that.

>>Dolby has extended the Dolby TrueHD format, used in Blu-ray discs, to allow the format to carry Dolby Atmos content. Before Dolby Atmos, Dolby TrueHD included lossless support for channel-based audio, such as 5.1 and 7.1. We have added a fourth substream for Dolby Atmos sound. This substream represents a losslessly encoded fully object-based mix.
 

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I would like to thank you for this note. Of course each TrueHD sub-stream includes audio signal. But I woudl like to check it in another side[/FONT]
1). This diagram above is a little bit incorrect. In accordance with classic TrueHD structure the main sub-stream should be full stereo downmix 2.0 (not 5.1). Decoder reconstructs 5.1 from the main stereo downmix 2.0 plus the 3.1 channel extension A (re-matrixing). The same for 7.1 - the decoder uses the reconstructed 5.1 and reconstructs 7.1 with the next 2.0 channel extension B.


That diagram was drawn based on the info from this thread and TrueHD papers from Dolby.

In the Channel Extensions, Downmixing, and Dolby TrueHD section, you can read:
One channel extension technique is the method by which MLP Lossless, Dolby TrueHD, and MPEG-2 LII deliver compatible downmixes for soundtracks with expanded channels. In these codecs, a 7.1-channel soundtrack is first downmixed to create a 5.1 mix, which is supplemented by a two-channel extension (which we’ll call “extension B”). The 5.1 mix is then further downmixed to a two-channel stereo mix, and another supplemental stream is created that carries the 3.1-channel “extension A.
Immediately after this paragraph, the paper forgets about the 5.1 downmix and states:
So the 7.1-channel program is delivered in three separate components: a two-channel mix, the 3.1-channel extension A, and the two-channel extension B.

You are quite correct. I'm not sure where that diagram originated -- but apparently not Dolby. ;)
True, not by Dolby, but by me.


Thus, the 4th substream is fully comprised of objects, but only those objects that are necessary to reconstruct the spatially coded Atmos version of the soundtrack.
True, if the 4th substream would contain full bed+objects the core 5.1/7.1 bed extraction would be more difficult, the spatial coding is used just to limit the bandwidth by mixing objects together in time (waveform) and space (by metadata), and the resulting object mix is used to cancel the objects from the legacy substreams.
So instead of a maximum of 118 objects - spatial coding clumps (mixes) together the objects in time and space. Near (in space) and simultaneous playing objects are mixed in the same waveform (cluster), other objects separated by space get another waveform (cluster), reducing the need to store a maximum of original 118 objects/waveforms to very few waveforms (clusters).

But things are a little more complicated than that, the TrueHD+Atmos format supports the following combination of content when the TrueHD container is set as "Meridian Lossless Packing FBA with 16-channel presentation" - very common on 4K UHD BluRays:

1. 16-ch presentation consists of loudspeaker feeds
2. 16-ch presentation consists of Intermediate Spatial Format (ISF) audio
3. 16-ch presentation consists of loudspeaker feeds followed by Intermediate Spatial Format (ISF) audio
4. 16-ch presentation consists of loudspeaker feeds followed by dynamic objects
5. 16-ch presentation consists of Intermediate Spatial Format (ISF) audio followed by dynamic objects
6. 16-ch presentation consists of loudspeaker feeds followed by Intermediate Spatial Format (ISF) audio followed by dynamic objects
So, the TrueHD container can carry ISF clusters AND objects besides legacy channels (loudspeaker feeds), or other combinations.
In Dolby's above document, dynamic objects are defined as "objects with potentially varying properties such as position" that are not to be confused with ISF audio (clusters).
ISF audio can be used as bed channels but not necessarily, the document shows that you can have ISF's that "emulate" channels and at the same time ISF's that are separate from bed channels, along with dynamic objects (non-ISF).

Example using MediaInfo:

Zombieland 2009 4K UHD BluRay TrueHD 7.1
Audio #1
ID : 2
Format : MLP FBA 16-ch
Format/Info : Meridian Lossless Packing FBA with 16-channel presentation
Commercial name : Dolby TrueHD with Dolby Atmos
Codec ID : A_TRUEHD
Duration : 1 h 27 min
Bit rate mode : Variable
Maximum bit rate : 4 956 kb/s
Channel(s) : 8 channels
Channel layout : L R C LFE Ls Rs Lb Rb
Sampling rate : 48.0 kHz
Frame rate : 1 200.000 FPS (40 SPF)
Compression mode : Lossless
Title : Atmos 7.1
Language : English
Default : Yes
Forced : No
Number of dynamic objects : 11
Bed channel count : 1 channel
Bed channel configuration : LFE
 
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