Problems with including the "Wide" channels of a Dolby Atmos 9.1.6 configuration

I admit that the wording of my concern and the title line gave me quite a headache. So I will describe our problem in a bit more detail:

We have equipped our UHD/BD authoring studio with a Dolby Atmos 7.1.4 speaker system. We have decided to use Nuendo as our DAW. We want to give ourselves an additional way to make small corrections to the Atmos mix before authoring. The delivery from our main sound studio is usually in 9.1.6, which is a problem because Nuendo doesn’t allow for monitoring beyond 7.1.4 channels. So we decided to only output Channel Based Immersive (CBI) mixes to the authoring studio. Now for my problem: When the Atmos mix is saved again after editing, the 9.1.6 configuration must of course be preserved.
What I managed to do is that the six treble speakers (Ltf / Rtf / Ltm / Rtm / Ltr / Rtr respectively Tfr / Tfl / Tsl / Tsr / Tbl / Tbr) are correctly written to the ADM file. However, the Left wide (Lw) / Right wide (Rw) channels cause me difficulties. Since Steinberg only has 7.1.4 in mind for Dolby Atmos in Nuendo, there is unfortunately no corresponding 9.1.6 template which would fit. Although this would be a really very helpful thing for a CBI mix. The 9.1.6 template available in Nuendo unfortunately has the wrong speaker configuration. And even with the higher formats (e.g. 22.2) I can’t select speakers that would correspond to the Lw / Rw position.
I would define the two “Wide” channels as objects. But since they are positioned so close to the front and side speakers, there is constant crosstalk to the front and side speakers respectively when I do this. And unfortunately, the selectable object zones are not fine enough to prevent this crosstalk. That’s why I was hoping to solve this with the “bed mode”, because I can completely disable speakers there.

So my question: Has anyone faced a similar problem and found a solution for it? Or has exact object coordinates at hand that only address the Lw / Rw speakers? I am also enthusiastic about unconventional ideas. (After all, our whole 9.1.6 workflow is rather unorthodox).

And to Steinberg I would have the request to provide with one of the next updates also a Dolby Atmos compliant bed layout, where the speakers correspond to the configuration L / R / C / LFE / Ls / Rs / Lrs / Rrs / Lw / Rw / Lfh / Rfh / Ltm / Rtm / Lrh / Rrh. Where each speaker can also be displayed in the sound field and decided on or off. We may be an exception with this request. Nevertheless: Such a bed layout would be extremely helpful. And this is independent of whether the integrated Atmos renderer can render this or not.

I appreciate any tip or suggestion that doesn’t call for directly editing the metadata. Because we already had this in mind as a last resort. :grin:

I thank you already very much for your interest and your answers.

I have now found a possible solution. In the first step, we use WaveLab to remove the metadata from our ADM file, which we previously exported from Nuendo. We then get a nested 16 channel file. This is accepted as input by the Dolby Encoder Engine.
However, we can only encode in E-AC-3 JOC. TrueHD with Atmos does not work. As a result we get an E-AC-3 JOC file with a bed channel count of 16 channels (9.1.6).

We still have to experiment with the settings, because the volume is not right and also the order of the channels is wrong. Not ideal, but at least it works in principle.

However, it would be better if we could route the channels Lw/Rw specifically as “DirectSpeakers”. But there I haven’t found a solution yet. Also as objects it does not work yet. Unfortunately, they can’t be positioned in such a way that the signal really only comes from the Lw/Rw speakers.

So if you have any ideas, please feel free to share them. :grinning:

Perhaps for testing and calibration purposes, you can try to encode with the Dolby Atmos AWS-Service (link is posted somewhere here in the forum). It allows 16x discrete WAV files to be uploaded. From what I have heard, also ADM-Files can now be uploaded. But this service gives back only DD+ with Atmos and no TrueHD.

Further background: Was thinking to extend my equipment from 7.2.4 to 7.2.6 (plus top side) or even 7.2.7 (plus Top Center) to have a more homogeneous playback. Gave it up after some thinking, since N12 and its Dolby Atmos Renderer is limited to 7.1.4.

Other issue is, that there are not many consumer AVRs available, which go beyond 7.1.4 Dolby Atmos processing. From what I know, only the quite pricey Trinnovs can do it. Perhaps there are som others too.

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Thank you very much.
As written, we are already realizing this with the Dolby Encoding Engine (DEE). With this we can encode our interleaved 16-channel files to E-AC-3 JOC ourselves.
For our Blu-rays, however, we would like to have TrueHD with Atmos. But as soon as we want to encode an interleaved 16-channel file to this format, the DEE rejects the file saying “too many channels”.
So to encode 9.1.6 in TrueHD with Atmos, we absolutely need an ADM file. But there we are faced with the problem, which I have already described above.

Whereby this is an “artificial” restriction that only affects monitoring in Nuendo. Not mixing.
We were able to determine this using the ADM files from our main sound studio. Its speaker configuration is 9.1.6. And when we edit the ADM files from there in Nuendo and then output them again, the result is still 9.1.6. (While we are working in Nuendo, however, we can only monitor in 7.1.4. But the ADM file does not care about the set channel configuration of the renderer. :wink: )
We therefore want to work channel-based immersive (CBI) for special cases. And if Nuendo had a Dolby-compliant 9.1.6 layout, we could route each channel to the right speaker. No matter if Nuendo’s built-in renderer can only do 7.1.4.

Unfortunately, with Nuendo, I’ve only been able to get 7.1.6 to work so far. To address the two Lw/Rw channels, a corresponding template is missing. (I’m still trying my luck with objects. Maybe I can still find coordinates which outputs the signal exclusively to the Lw/Rw channels.)
I realize, of course, that this workflow is only suitable in certain cases. Not everyone wants to mix based on channels. Or can’t mix without being able to immediately monitor the result in 9.1.6 as well. But for us, a Dolby-compliant 9.1.6 template would help. (Even better, of course, would be if Nuendo’s built-in Atmos renderer allowed monitoring in 9.1.6. But Dolby will probably want to reserve that for its own renderer.)

That’s true. There are not many AV receivers that can play back this channel configuration. This is probably why Dolby recommends 7.1.4 as the default configuration.
We mix with 9.1.6 because it works and doesn’t hurt anyone. :slight_smile: Also, 9.1.6 is the maximum possible configuration when encoding an ADM file into a consumer format (E-AC-3 JOC /TrueHD with Atmos). We don’t want to leave this potential unused.
But basically, with an object-based audio format, channel configurations shouldn’t really matter anymore. But they will probably accompany us in the future as well. :wink: