NextGen Audio: Tempest Engine, Project Acoustics, Windows Sonic, Dolby Atmos, DTS X

It's being said they wont support it in games, snippets from post:

More annoyingly, they AREN'T going to be supporting Dolby Atmos natively on their hardware. Microsoft are (and indeed already do on XBOne in a limited fashion).​

Atmos is a major change in how we encode and output audio from the hardware, that allows a more accurate surround experience from whatever speaker setup you have. It requires multiple speakers around you and an Atmos decoder amp, which 99% of people don't yet have but it is a growing market.​

Due to the nature of game audio engines, Atmos is a natural fit for it anyway - we have been positioning hundreds of emitters in 3d space for decades, so Atmos simply put allows us to position those into your speakers rather than that information be added to a generic 5.1 or 7.1 downmix.​

What we really want, those of us making multi-platform titles, is parity between consoles - so that we can make the game once and not have to mix differently for each platform. The lack of hardware Atmos support is bad because it means if we want to do it, it will have to be added by software and incur a CPU cost that the Xbox won't.


I find it hard to belive when there must be a Dolby Atmos decoder in there, but I do not know how that work for games. I thought you just fed the game audio stream through the decoder. How is it done today with the Dolby Digital and DTS decoders?.Anyway I do not see this post as a confirmation. We need it from the horses mouth. Just added to all the details that is still not talked about by Sony.
 
I have two 5.1 setup (one gaming room and one living room) and have not bothered to add height speakers, so I would be interested to know if any of the two virtual height channels (DTS virtual x and Dolby Atmos Height Virtualization) are supported.
 
I have two 5.1 setup (one gaming room and one living room) and have not bothered to add height speakers, so I would be interested to know if any of the two virtual height channels (DTS virtual x and Dolby Atmos Height Virtualization) are supported.
They should be yea for games that support it. I would love to have a similar setup. I don't know games that support DTS:X though. Dolby Atmos games there are only a handful.
 
Why is it a concern that next-gen consoles can't output Dolby Atmos?

If you have a home theater surround system, then it supports LPCM though HDMI. There's no need to compress the source.
And if the game works on Atmos, then decompress on the PC/console and send the LPCM.
Just like what happens in PS4 games with "Dolby" or "DTS" sound processing but you select LPCM as audio output.
 
I find it hard to belive when there must be a Dolby Atmos decoder in there, but I do not know how that work for games. I thought you just fed the game audio stream through the decoder. How is it done today with the Dolby Digital and DTS decoders?.Anyway I do not see this post as a confirmation. We need it from the horses mouth. Just added to all the details that is still not talked about by Sony.

But not an encoder. You would first need a pathway for a game to output a Dolby Atmos or DTS:X bitstream and then, to use even their 50% allocation of Tempest audio, they'd have to use/develop an implementation of a Dolby Atmos/DTS:X that runs on the hardware. In this scenario the system allocation would sit idle since it's HRTF function would not be being used (in favor of Dolby and DTS's).
 
Why is it a concern that next-gen consoles can't output Dolby Atmos?

If you have a home theater surround system, then it supports LPCM though HDMI. There's no need to compress the source.
And if the game works on Atmos, then decompress on the PC/console and send the LPCM.
Just like what happens in PS4 games with "Dolby" or "DTS" sound processing but you select LPCM as audio output.

Because your receiver (where the ATMOS decoding is being done) knows what speakers you have, where they are and how loud they are (assuming Audyssee or some other calibration was used) and can do a better job positioning sounds in your specific configuration. There's a reason Atmos and DTS:X are their own things as opposed to just 9.1(+) versions of the existing codecs.
 
I prefer bitstream over LPCM and use the decoders in the AVR's, because they normally are of higher quality.

If you get anything other than identical output from a decoder than the decoder isn't lower quality, it's broken. Any difference in sound would be down to the sound information taking a different pathway through the circuitry in the endpoint device.
 
If you get anything other than identical output from a decoder than the decoder isn't lower quality, it's broken. Any difference in sound would be down to the sound information taking a different pathway through the circuitry in the endpoint device.

He he, placebo you know :D, anyway it would feel bad to not use the decoders in the 2000 dollar AVR:yes:
 
Because your receiver (where the ATMOS decoding is being done) knows what speakers you have, where they are and how loud they are (assuming Audyssee or some other calibration was used) and can do a better job positioning sounds in your specific configuration. There's a reason Atmos and DTS:X are their own things as opposed to just 9.1(+) versions of the existing codecs.
Room calibration works for any source, LPCM or even analog inputs included. They adjust phase and volume over what should considered "ideal".
And if the new consoles decide to offer height channels, then I'm pretty sure it shouldn't be hard to define in the system which of the 32 LPCM virtual placements for 3D audio the height speakers correspond to.
 
Room calibration works for any source, LPCM or even analog inputs included. They adjust phase and volume over what should considered "ideal".
And if the new consoles decide to offer height channels, then I'm pretty sure it shouldn't be hard to define in the system which of the 32 LPCM virtual placements for 3D audio the height speakers correspond to.

I'm unaware of any implementation of this. AFAIK, both source and sink device manufacturers have preferred to stick to using the proprietary (but fully realized) Dolby and DTS implementations instead of rolling their own. There's a difference between a sink device getting data that says "play these waveforms on these speakers at this loudness" and "put this sound here in the soundfield". That's why no one even supports a mechanism for a source to direct sound to those speakers outside of a bitstream.
 
Why is it a concern that next-gen consoles can't output Dolby Atmos?

If you have a home theater surround system, then it supports LPCM though HDMI. There's no need to compress the source.
And if the game works on Atmos, then decompress on the PC/console and send the LPCM.
Just like what happens in PS4 games with "Dolby" or "DTS" sound processing but you select LPCM as audio output.
LPCM only supports up to 8 channels over HDMI. That's fine for a traditional "flat" 7.1 setup, but doesn't scale to a proper Atmos setup with height speakers (ideally 7.1.4).
 
I'm unaware of any implementation of this. AFAIK, both source and sink device manufacturers have preferred to stick to using the proprietary (but fully realized) Dolby and DTS implementations instead of rolling their own. There's a difference between a sink device getting data that says "play these waveforms on these speakers at this loudness" and "put this sound here in the soundfield". That's why no one even supports a mechanism for a source to direct sound to those speakers outside of a bitstream.
What I'm saying is once you're sending the audio through LPCM, it should be easy for a console to just trick any 7.1 A/V receiver to work as 5.1.2 (or a 9.1 as 5.1.4). Just send the 2/4 height channels into the receiver as if they were side speakers and physically place them as such.
If you use LPCM on games, you don't really need Dolby Atmos or DTS:X encoding.

LPCM only supports up to 8 channels over HDMI. That's fine for a traditional "flat" 7.1 setup, but doesn't scale to a proper Atmos setup with height speakers (ideally 7.1.4).
That's only for HDMI 1.4 and below.
HDMI 2.0 and 2.1 support up to 32 LPCM channels at up to 24bit 192KHz.
For games coming from a game console, you don't really need atmos to reach 7.1.4. You just need an AV receiver with 11 amplified speaker outputs plus a subwoofer preamp output.


All the Dolby / DTS compressed technologies are important for video streaming and optical disks to save bandwidth on the first and storage on the second. In a game your're creating the final output on the fly, so this doesn't matter.
 
So the blurb on Spatial Audio basically confirms that XBSX has hardware acceleration for HRTF as well as 3D positioning in game space.

I'm guessing Project Acoustics is to handle the physical sound characteristics and modeling of the world and geometry (how sound interacts with the world around you before it reaches your ears) while Spatial Audio is there to handle more dynamic sound sources as well as the location of the sound sources in the 3D soundscape.

Obviously a very naïve and simplistic description of what is going on as Project Acoustics will alter and modify the sound such that by the time the sound reaches your ear, it may not be coming from the direction where it originated (obstruction, for example) or from multiple directions (reflection, for example) with appropriate delays due to sound propagation (like echoes).

Regards,
SB

The HRTF calculations, from what I understand, are essentially the same as the reverb calculations, just with far shorter impulse response times. The only opportunities I see for meaningful hardware acceleration are convolution reverb/HRTF and potentially hardware decoding of their compressed lookup table that's produced by project acoustics. I'm expecting something like a typical audio dsp. I'm expecting PS5's audio processor to be considerably more powerful because their focus is on real-time, where Microsoft's focus seems to be on baking offline. Project Acoustics is a very smart optimization, and it's something that would serve PS5 well. With project acoustics, you have a way of massively reducing the amount of calculations you need for all kinds of audio simulations, and probably at much higher quality than at doing it real-time. In the end, you still have a number of audio effects in your scene, and the audio processor will need to take the impulse response project acoustics provides and perform the reverb calculations. So it becomes a question of how many audio sources the processor can handle to know how many you can put in your scene.
 
What I'm saying is once you're sending the audio through LPCM, it should be easy for a console to just trick any 7.1 A/V receiver to work as 5.1.2 (or a 9.1 as 5.1.4). Just send the 2/4 height channels into the receiver as if they were side speakers and physically place them as such.
If you use LPCM on games, you don't really need Dolby Atmos or DTS:X encoding.

Standard speaker layouts exist for a reason. Arbitrarily moving speakers around to enable one specific non-standard implementation to work while simultaneously breaking everything else is a terrible idea. And I still don't accept the premise that an object-oriented bitstream sent to a decoder conveys no benefit over just sending some number of LPCM channels. Why does the 3D audio spec you reference even exist then? Wouldn't it be redundant?
 
Standard speaker layouts exist for a reason. Arbitrarily moving speakers around to enable one specific non-standard implementation to work while simultaneously breaking everything else is a terrible idea.
Who's going to change what layout?
The PS5 will probably output Dolby Atmos to a receiver if you're using it for Netflix or watching a UHD Bluray. If you have a 5.1.2 configuration, then your AV Receiver together with Atmos already knows where the speakers are and provides the sounds accordingly.
But if you're playing a game with a 3D audio engine, there's no need to encode it into Atmos and spend precious compute power on that, just to decode it on the receiver. Just send the 2 top channels as if they were surround back channels on a 7.1 configuration through LPCM and the receiver will just forward the audio to the top speakers.

Have you seen how an A/V Receiver with Atmos names the height speaker outputs? The surround back speaker outputs are the same as the top speaker ones, and they also triple as bi-amplifiers to the main speakers:

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The reason why the 2013 consoles had Dolby Digital encoding is probably because they figured a lot of people were still using old surround systems without HDMI, and the only way they'd get surround sound would be with Dolby Digital sent through Optical SPDIF. That's going away this gen, since as you've seen the SeriesX has no optical output anymore, and I'd bet the PS5 won't have it either.
For this gen they assume most people with surround sound setups will have:
- At least a HDMI 1.4 receiver with ARC, through which they can send stuff encoded into Dolby Digital Plus for typical 5.1/7.1 setups.
- A HDMI 2.0 equipped receiver that supports Atmos sitting between the console and the TV, through which they can send the height channels through the LPCM surround back channels.
- A HDMI 2.1 TV and a receiver that supports eARC, through which they can send the same audio streams as if the receiver was sitting between the consoles and the TV.
The beauty of eARC is that now we can use the same AV Receiver forever. By supporting LPCM through eARC, we're never going to be limited by a new format or a new HDMI version that provides more video bandwidth. We'll always be able to use the 24bit 192KHz per channel of LPCM and use a standard HDMI cable from the TV to get it.




And I still don't accept the premise that an object-oriented bitstream sent to a decoder conveys no benefit over just sending some number of LPCM channels.
Absolutely no one wrote that. At least I didn't.
First of all, there's the benefit of compression. If it weren't for Dobly / DTS we wouldn't have multichannel surround on optical disks and streaming video.
Secondly, a video using object-oriented audio means it's supposedly agnostic to amount of speakers, which is very welcome addition to home theater setups. A 11 channel receiver wouldn't know what to do with an old Dolby Digital 5.1 audio stream, other than place the front+center+rear+sub on their respective places and do something like an average output of two channels for the channels in between. With Dolby Atmos you can theoretically have dozens of speakers and all of them will have a distinct output based each virtual source.

What Atmos doesn't bring benefit for, in a home theater surround system, is for games, because games have been using object-based bitstreams created by their 3D audio engines for decades.
If you can use LPCM through HDMI (and with eARC you can use LPCM in pretty much any situation), there's very little reason to bother encoding your videogame audio engine's output into Dolby Atmos just to send it through HDMI and decode it on the other receiver. Unless you're using a very tightly integrated solution like a soundbar but those wouldn't do any decent surround sound anyways.
 
@ToTTenTranz So, I think his point was the receiver is able to render the sound objects into the correct positions in the channels because the receiver can be aware of the physical locations of the speakers relative to the listener. For example, you'd record the physical distance of each speaker to the listener and provide those to the receiver so it can balance the mix correctly based on your exact speaker layout. I don't mess with home theatre, but my understanding is these room calibrations are common now, and a console that was mixing the audio into channels before sending it to the receiver would lose the benefit of receiver mixing the sound objects for your particular setup. Of course, the console could support the same type of room calibration.
 
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