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Loudness wars are over - with lossy Dolby Atmos

Soniclife

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If they mixed it as loud digitally as they would stereo we're talking about instant complete hearing loss, +150 dBSPL.
They have volume controls in mastering suites, they are not producing these crushed CD mixes at max volume.
 

goat76

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I wouldn't celebrate just yet. For most mastering engineers Atmos is still a relatively new delivery format which means they end up sticking to the guidelines. But as your numbers for the Weeknd release show, Dave Kutch is already working on breaking the equal loudness rules. All the Weeknd tracks have the same LUFSi, and so will pass a simple loudness scan, but he's working on compensating for this by changing the way he limits the audio. This is most obvious for Sacrifice, which has a true peak down at -8dB (!) leading to a miserable crest factor. We'd need to actually look at the audio waveforms to work out precisely how he's mangling the audio for the other two though.

iTunes tried to discourage hard-limiting by refusing to certify audio that clipped at 0dB. Mastering engineers just evaded that by limiting at -0.3dB instead, leading to the same crappy flat-topped clipping distortion, only at a very slightly lower level. I have no doubt that if Atmos becomes a reasonably popular delivery format then engineers will work on ways to break its rules in the same manner.
I can’t see how they will get around the loudness limit of -18 LUFS set for Dolby Atmos. They can of course limit the music as much as they want, but never get around the LUFS normalization level that is based on average volume. At least they will get more headroom for sure. :)
 
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Music1969

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The ‘Atmos’ you get via a USB DAC on Apple music is nothing but a binaural downmix of the whole thing which sounds really bad on stereo speakers.

Looking a bit more into it.

Apple's Atmos is crapper than Amazon's and Tidal's.

I just measured Apple vs Amazon - same high DR but Amazon sounds like stereo version but with much higher DR.

Apple's does sound really bad as you said. The explanation is given here below.

Dua Lipa's Levetatin (which I measured in OP) is a great example of how crap it sounds on Apple Music with USB DAC.

But then Amazon Music app resamples everything to PCM192kHz in 'Exclusive Mode' lol

I'm using headphones by the way - I haven't listened on stereo speakers.


1647002304295.png
 

abdo123

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Looking a bit more into it.

Apple's Atmos is crapper than Amazon's and Tidal's.

I just measured Apple vs Amazon - same high DR but Amazon sounds like stereo version but with much higher DR.

Apple's does sound really bad as you said. The explanation is given here below.

Dua Lipa's Levetatin (which I measured in OP) is a great example of how crap it sounds on Apple Music with USB DAC.

But then Amazon Music app resamples everything to PCM192kHz in 'Exclusive Mode' lol

I'm using headphones by the way - I haven't listened on stereo speakers.


View attachment 191705
I don’t personally find the binaural downmixes bad when you listen to them on headphones.
 
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Music1969

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I wouldn't celebrate just yet. For most mastering engineers Atmos is still a relatively new delivery format which means they end up sticking to the guidelines. But as your numbers for the Weeknd release show, Dave Kutch is already working on breaking the equal loudness rules. All the Weeknd tracks have the same LUFSi, and so will pass a simple loudness scan, but he's working on compensating for this by changing the way he limits the audio. This is most obvious for Sacrifice, which has a true peak down at -8dB (!) leading to a miserable crest factor. We'd need to actually look at the audio waveforms to work out precisely how he's mangling the audio for the other two though.

iTunes tried to discourage hard-limiting by refusing to certify audio that clipped at 0dB. Mastering engineers just evaded that by limiting at -0.3dB instead, leading to the same crappy flat-topped clipping distortion, only at a very slightly lower level. I have no doubt that if Atmos becomes a reasonably popular delivery format then engineers will work on ways to break its rules in the same manner.

Amazon Atmos:

1647193674062.png


Amazon Lossless (same as Apple Music Lossless) - loudness norm. obviously off here. Turn on, no clipping but same DR.

1647193719327.png
 

charleski

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Unfortunately the clipping markers obscure the waveform (turn off View->Show Clipping). It would be helpful to see what the Lossless file looks like with loudness norm turned on to match the output from Atmos. I suspect he might be using a leaky compressor that crushes most of the peaks but lets a few stray ones through.
 
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Music1969

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Unfortunately the clipping markers obscure the waveform (turn off View->Show Clipping). It would be helpful to see what the Lossless file looks like with loudness norm turned on to match the output from Atmos. I suspect he might be using a leaky compressor that crushes most of the peaks but lets a few stray ones through.
This is with Apple Music's SoundCheck enabled

I think you're right - crushed peaks compared to Atmos version.


1647196931960.png
 
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Music1969

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Unfortunately the clipping markers obscure the waveform (turn off View->Show Clipping). It would be helpful to see what the Lossless file looks like with loudness norm turned on to match the output from Atmos. I suspect he might be using a leaky compressor that crushes most of the peaks but lets a few stray ones through.

Amazon Lossless (no loudness normalisation) with clipping markers turned off

1647197117492.png
 
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Music1969

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Atmos version (Amazon's) for the win with this album. And I don't even like Amazon itself.

And the Dua Lipa album. And several more I've looked at since.

Lossy but much better DR.
 

charleski

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Yeah, Kutch is just shaving off all the peaks. The TPL numbers you got before are probably just a result of the program trying to interpolate the insane clipping, but it doesn’t look like he’s doing anything sophisticated.
 

Sancus

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The ‘Atmos’ you get via a USB DAC on Apple music is nothing but a binaural downmix of the whole thing which sounds really bad on stereo speakers.
I just want to point out that this is apparently not the case if you have a multi-channel USB DAC. If you have that, MacOS will actually output Atmos to your multiple speakers, without the use of an external hardware decoder like an AVR.

This, to my knowledge, is unique, though if the other information in this thread is correct it's probably using Apple's Spatial Audio Renderer and not the Dolby one, which would explain how they can do this because normally Dolby says 'hell no' to providing a software renderer. It would be interesting to compare the results in this case to the real Atmos Renderer.

AppleTV will bitstream Atmos to a hardware renderer like an AVR so it would be possible to A/B test. Rather a pain to set up since you'd also need a Mac, a multi-channel DAC, and some way to switch all channels between an AVR and DAC.
 
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Music1969

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I just want to point out that this is apparently not the case if you have a multi-channel USB DAC. If you have that, MacOS will actually output Atmos to your multiple speakers, without the use of an external hardware decoder like an AVR.

This, to my knowledge, is unique, though if the other information in this thread is correct it's probably using Apple's Spatial Audio Renderer and not the Dolby one, which would explain how they can do this because normally Dolby says 'hell no' to providing a software renderer. It would be interesting to compare the results in this case to the real Atmos Renderer.

AppleTV will bitstream Atmos to a hardware renderer like an AVR so it would be possible to A/B test. Rather a pain to set up since you'd also need a Mac, a multi-channel DAC, and some way to switch all channels between an AVR and DAC.

It's a shame Amazon Music app and Tidal Desktop app on macOS can't play Atmos yet.

Those 2 don't do any weird and funky Spatial Audio crap that Apple does.

Apple does their Spatial Audio crapola to suit their headphones of course but not great for any 2-channel with non-Apple headphones.
 
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Music1969

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Yeah, Kutch is just shaving off all the peaks. The TPL numbers you got before are probably just a result of the program trying to interpolate the insane clipping, but it doesn’t look like he’s doing anything sophisticated.
Just one more. Another mainstream release.

Much better DR with Atmos version on Amazon Music - proper binaural version without Apple's Spatial audio crap which with Apple Music makes it sound weird on non-Apple Spatial gear.


1647226137950.png


Amazon Lossless, normalization off

1647226370965.png


Amazon Loss, normalization ON

1647226411949.png



Amazon Atmos (much better !!)

1647226433275.png



My wishes:

1. Apple updates their Atmos codec and allows proper binaural with non-Apple gear. Per mastering link I shared above. Maybe unlikely because Apple spatial audio gear is selling like hotcakes and will continue to. Their VR headsets coming too. They want to control that entire Spatial Audio experience with their gear.

2. Amazon and Tidal Desktop apps support Atmos playback

3. Unlikely but TrueHD Atmos comes to all those streaming services, instead of Lossy

In everything I look at, loudness wars are over with these Atmos versions.

Much much better dynamic range even with the really popular stuff you wouldn't expect to have good DR.
 
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Music1969

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One more datapoint.

Different album. Again this is mainstream music, not targeted at people that really care about DR.

And again the lossy Atmos version has much better dynamic range than the LOSSLESS versions, no matter if normalization is on or off.

1647227252520.png


Amazon Atmos version (best dynamic range):

1647227045118.png


Amazon Loss - with normalization ON:

1647227190206.png



Amazon Lossless with normalization OFF:


1647227146618.png
 
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Music1969

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I wasn't prepared for this.

Amazon's lossy Atmos absolutely smokes the 24/96 versions on Apple Music, Qobuz etc

1647353514104.png


1647353526029.png
 

kongwee

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Because of LUSF, DR isn't that important for streaming for pure loudness than enjoyment.
 
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Music1969

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Because of LUSF, DR isn't that important for streaming for pure loudness than enjoyment.

Not sure what you mean. Have you seen the wave forms above, even with normalization enabled? Comparing with disabled.
 
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