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Atmos finally decoded in PC/Mac

voodooless

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Yes, but not only: if you find an AVR that accept more than 8 channels (PCM) by HDMI (it would be absolutely possibile, as per HDMI 2.0b and 2.1 specs), you win a Caraibic holiday...
But if the idea is to bypass the AVR, that is irrelevant.

Why would Windows have this limitation? How do these multichannel audio interfaces work then, that have more than 8 channels? Something like Behringer UMC1820 has 20 outputs. Basically, al DAWs have no issues with this.
 

VoidX

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No, the issue with audio from streaming providers is that audio is dynamic compressed in the master, as I've written.
That's Disney like you said, there's no way to fix their tracks, but I've got a few samples I can show you the waveform of with and without DRC enabled, they're really different.

This is interesting, can you recommend any links or articles on it?
On other codecs or Dolby's suffering?

Ah, is that just a Windows limitation then?
Yes, you can't tell the OS that you need more channels than 8, it won't grant you an output, even if there are way more channels. This is only possible on very low level.

Yes, but not only: if you find an AVR that accept more than 8 channels (PCM) by HDMI (it would be absolutely possibile, as per HDMI 2.0b and 2.1 specs), you win a Caraibic holiday...
And there's no standard channel order. PCs use L R C LFE RL RR SL SR, some media players (like Dune) use L R C SL RL RR SR LFE...
 

VoidX

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Why would Windows have this limitation? How do these multichannel audio interfaces work then, that have more than 8 channels? Something like Behringer UMC1820 has 20 outputs.
Because there's no standard beyond 8 channels, only Atmos, which Windows supports via bitstreaming. The studio interfaces are handled directly from the DAW, with a custom layout. Using a layout editor is complicated for the average user. There are also licensing issues.
 

voodooless

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Because there's no standard beyond 8 channels, only Atmos, which Windows supports. The studio interfaces are handled directly from the DAW, with a custom layout. Using a layout editor is complicated for the average user.
Yeah, obviously there is no layout because you can use these channels arbitrarily. That's what your decoder can do as well I would guess?

For true Atmos, one would expect that you just set up speakers in 3D space, and that it will then render the input soundtracks to these speakers, no matter how many, or where they are placed.

As for complicated for the user: any endeavor to make a PC a full-fledged AV processor will make it a complex matter. Adding one more thing to configure doesn't seem too much to ask to come closer to the goal.
 

VoidX

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Yeah, obviously there is no layout because you can use these channels arbitrarily. That's what your decoder can do as well I would guess?
Yes, with a complete 3D editor in the Driver, but after user reports, it was dumbed down to a preset selection for the converter. In the case of Atmos, where most content have static objects, making them basically channel-based, this is a fool-proof approach, that's why AVRs also don't allow free channel placement.
 

voodooless

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Yes, with a complete 3D editor in the Driver
That's fantastic :cool:
but after user reports, it was dumbed down to a preset selection for the converter.
Hopefully, it still supports both options.
In the case of Atmos, where most content have static objects, making them basically channel-based
That defeats the whole purpose of Atmos, doesn't it?
this is a fool-proof approach, that's why AVRs also don't allow free channel placement.
I know the Yamaha's at least measure the speaker distances, angles, and height in 3D space. I guess they should be able to do the proper rendering. Speakers al almost never set up perfectly in the right spot unless there is a dedicated room, and most people don't have that. It should be a very valuable feature.
 

VoidX

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Hopefully, it still supports both options.
In different programs, but yes.

That defeats the whole purpose of Atmos, doesn't it?
It's a compromise for space. Home Atmos is not ready for true 3D, only height. Barely anyone wanted more, and Dolby wouldn't want to work for those 10 users. All development is guided by what the majority can/want to do.

I know the Yamaha's at least measure the speaker distances, angles, and height in 3D space. I guess they should be able to do the proper rendering. Speakers al almost never set up perfectly in the right spot unless there is a dedicated room, and most people don't have that. It should be a very valuable feature.
Even if you use the editor, it won't be close to the real soundstage because of the reflections. I don't know what Yamaha does, but that is only possible with very specific and guided microphone placement. I wanted to work on this without compromising the easy setup, but that's mathematically impossible, too many variables for too few equations.
 

voodooless

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Even if you use the editor, it won't be close to the real soundstage because of the reflections. I don't know what Yamaha does, but that is only possible with very specific and guided microphone placement.
That's exactly what they seem to do. They also claim to get rid of the first reflections.. But the better bet is the new Dirac Spacial Room correction.
 

VoidX

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That's exactly what they seem to do. They also claim to get rid of the first reflections.. But the better bet is the new Dirac Spacial Room correction.
The first reflections shouldn't be removed as you also hear the distorted speaker position because of them. I would say the leader in this aspect is Duran, they can reproduce the room in 3D just by sound, nobody comes close to this.
 

Digimaster

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It's a compromise for space. Home Atmos is not ready for true 3D, only height. Barely anyone wanted more, and Dolby wouldn't want to work for those 10 users. All development is guided by what the majority can/want to do.
It's absolutely true. The "real" Dolby Atmos is the Theatrical version. The Home version loses many 3D data. That's it.
 

VoidX

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It's absolutely true. The "real" Dolby Atmos is the Theatrical version. The Home version loses many 3D data. That's it.
It's a downmix, it doesn't lose data on the targeted small systems. Why keep all objects, if it sounds exactly the same rendered to 16 channels? Yeah, it won't allow free speaker placement, but it's versatile enough for most users.
 

prerich

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Those are hardly ever controlled tests. Let's exclude MP3 here because it's known to be not transparent and obsolete anyway. We're talking Dolby Digital Plus specifically here. You can add high bitrate AAC as well if you like. Ever blind-tested that?

The same people also claim to hear differences in cables and DAC's that sound worlds apart, so how much should I rely on these subjective opinions?
There was a statistical test performed in 2007 when the Blu-Ray vs HD-DVD wars were being raged. I have the link but the graphs seem to be removed
The reason I mention HD-DVD is the fact that streaming is using the DD+ Codec that HD-DVD used. In that test it was proven that there was a discern-able difference between BD (lossless TrueHD,PCM,etc) and HD-DVD (lossy DD+). I actually have the Ghostbusters Afterlife on Vudu and I have the physical media as well. You can tell the difference in sound - and its no contest, BD has been proven to have more dynamic range than HD-DVD. This is part of what people are hearing (or should I say not hearing) when they stream. I also had a magazine (out of print) that had performed tests I forget which one it was, that tested a BD that had the same title in HD-DVD and the BD won due to its audio. I'm going to see if I can find it in the historical archives on line. DD+ = HD-DVD audio
 

voodooless

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There was a statistical test performed in 2007 when the Blu-Ray vs HD-DVD wars were being raged. I have the link but the graphs seem to be removed
This is just based on subjective reviews. it's meaningless.
The reason I mention HD-DVD is the fact that streaming is using the DD+ Codec that HD-DVD used. In that test it was proven that there was a discern-able difference between BD (lossless TrueHD,PCM,etc) and HD-DVD (lossy DD+). I actually have the Ghostbusters Afterlife on Vudu and I have the physical media as well. You can tell the difference in sound - and its no contest, BD has been proven to have more dynamic range than HD-DVD.
Where is the proof then? It can't be in the format. Because they all encode 24 bit audio just fine. There is no reason that DD+ would have less dynamic range, other than that it is a different mix or different metadata applied.
 
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VoidX

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proven to have more dynamic range
Yes, this is the issue. My testing had DRC disabled, you can't do this with an AVR. The codec has no issue, the studios who set the metadata have.

I have a codec comparison tool on my site called Nuance under microprojects, you can give it a try. It converts any WAV content to many codecs in real time and performs a double blind test.
 

voodooless

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I have a codec comparison tool on my site called Nuance under microprojects, you can give it a try. It converts any WAV content to many codecs in real time and performs a double blind test.
You may want to do something about your website though, the download will take about a 1 day :facepalm:

Edit:.. and now it's suddenly done. Curious.

Edit2: Sadly It doesn't want to run properly in Crossover:
1664547337330.png
 
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voodooless

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This is a known Unity bug, resizing the window (maybe after Alt + Enter) could fix this.
It starts full screen, and when I make it windowed, I can't change the size ;)
 

Digimaster

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That's Disney like you said, there's no way to fix their tracks, but I've got a few samples I can show you the waveform of with and without DRC enabled, they're really different.
No doubt that DRC make his job. But the real issue is that the soundtrack with no DRC sounds even so dynamic compressed respect to the Theatrical version. Disney, at this time, is the only Major that do this in streaming and Disc.
 

krabapple

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There are 2 reasons to prefer Atmos in TrueHD:
1) TrueHD is lossless, the difference when you listen in High quality HT is really big.

I rather doubt that. When tested fairly, I mean.
Lossy compression is lossy. In this word, there's all you need to know.

An incredibly ignorant thing to claim. Psychoacoustic modelling works. Codecs matter. Compression quality options matter.
 

VoidX

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It starts full screen, and when I make it windowed, I can't change the size ;)
You could try different resolutions, but I'd prefer a full Windows installation.

No doubt that DRC make his job. But the real issue is that the soundtrack with no DRC sounds even so dynamic compressed respect to the Theatrical version. Disney, at this time, is the only Major that do this in streaming and Disc.
Are dubbed versions released by different copyright holders normal? If they are, then Spleeter can come to the rescue, mixing foreign, dynamic versions with the speech from English, DRC versions.
 
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