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MQA trying to get the anti compression crew on side.


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The article looks to me as if Stereophile are finally admitting that there are issues with MQA   

This is the same stereophile that said; "I come away feeling that I was present at the birth of a new world" (Atkinson)

 

I'd like to think they are now taking a more reasoned approach but I wonder what's really happened in the background??

Edited by Sir Sanders Zingmore
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The deblurring component was always part of MQA but now they're pointing that out as its greatest benefit. Looks like their (Stereophile's) bull finally got called out by this modern communication world. This could spell some slightly more reasoned articles in the future with a little less instant glowing praise for unblinded science-less claims (haha yeah right :\)

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On 14/03/2018 at 9:26 AM, Ittaku said:

The deblurring component was always part of MQA but now they're pointing that out as its greatest benefit.

It's not that the "deblurring component' is "un-compressing" music that was compressed when "originally recorded", that's impossible to do back to a natural state. Only dynamic range expander's can "try" do that, and we all know what they sound like!

It's trying to fix what MQA itself does to the music itself.

 

Cheers George 

Edited by georgehifi
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I keep seeing the subject of MQA come up, so I get interested and do some reading each time.    I am left wondering "Why MQA?".     I am seeing it as a niche product where better (than MP3) quality audio from smaller data is absolutely required.  Meanwhile, for nearly every other purpose, Flac is better.   Then there is the whole  proprietary thing...

 

Here's a couple of interesting links (might have been posted before) that I just looked at

 

http://www.hifiplus.com/articles/highresaudio-to-stop-offering-mqa/

 

https://www.xivero.com/blog/hypothesis-paper-to-support-a-deeper-technical-analysis-of-mqa-by-mqa-limited/#6

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On 14/03/2018 at 9:26 AM, Ittaku said:

The deblurring component was always part of MQA but now they're pointing that out as its greatest benefit.

THIS.

 

 

MQAs biggest marketing hurdle right now, are people who are claiming the "format is not lossless".

 

Lossless is very strong word.   Any "loss" by definition means "not lossless".

 

However.... most people who are claiming that "MQA is not lossless" are IMVHO misguided.   There's no loss worth any attention....   and if we "ague against MQA" based just on this "I don't want lossy", then a bigger picture is potentially being missed.

 

On 19/03/2018 at 5:03 PM, georgehifi said:

It's not that the "deblurring component' is "un-compressing" music that was compressed when "originally recorded", that's impossible to do back to a natural state. Only dynamic range expander's can "try" do that, and we all know what they sound like!

It's trying to fix what MQA itself does to the music itself.

 

You seem to have misunderstood.

 

20 minutes ago, aussievintage said:

I am left wondering "Why MQA?". 

Distribute lossless music using less bandwidth.

 

Allow the capabilities of different players (eg. 16/44, 24/96, 24/386, etc.) be met, without resampling the audio at playback  (eg. if your content is 24/192, but you DAC only does 24/48, there is no (traditional) "resample" at playback to take the 192 -> 48.

 

To authenticate the "authenticity" of the content you are playing, by using encryption.  (ie.  you know the content hasn't "changed" since it left the studio)

 

Potentially many other things which the MQA system allows, which they haven't discussed openly yet.

 

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24 minutes ago, davewantsmoore said:

However.... most people who are claiming that "MQA is not lossless" are IMVHO misguided.   There's no loss worth any attention....   and if we "ague against MQA" based just on this "I don't want lossy", then a bigger picture is potentially being missed

to further my understanding... am I correct in saying that any losses are above 20kHz (or thereabouts)?

If that is correct, and these are not "worth attention", then what is the benefit of streaming hi-resolution music in the first place?

 

Or have I missed something (the most likely explanation !)

Edited by Sir Sanders Zingmore
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From the second link I posted

 

"

  1. MQA is in fact “lossy” because it alters the bit-depth and frequency response (magnitude & phase) and therefore time domain appearance of the original high resolution audio file by applying none-linear-phase filters impacting the critical audio spectrum (e.g. 4dB attenuation at 40kHz)."
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3 hours ago, davewantsmoore said:

You seem to have misunderstood.

I don't think so, MQA are not claiming that their deblurring  component magically" uncompresses compressed albums like Adel's  21, Skyfall and others, which have no dynamic range whatsoever.

http://dr.loudness-war.info/album/list?artist=adele+&album=

 

Cheers George   

Edited by georgehifi
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3 hours ago, davewantsmoore said:

You seem to have misunderstood.

I don't think so, I don't think MQA are claiming that their deblurring component "magically" uncompresses compressed albums like Adel's  21, Skyfall and others, which have no dynamic range whatsoever.

 

http://dr.loudness-war.info/album/list?artist=adele&album=21

 

http://dr.loudness-war.info/album/list?artist=adele&album=Skyfall

 

Cheers George

 

 

Edited by georgehifi
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Quote

If you're an audiophile who dislikes anything that smells of compression, MQA has added a "deblurring" feature. 

The author is incorrect to infer that the "deblurring" feature is somehow related to, or undoes the "MQA compression"  (ie.  representing everything above a certain sample rate in an encoded form ... and using the noise floor to repsent that data)

 

MQA "deblurring" does not do anything to undo "MQA compression".   Nothing.

 

 

It seems the claims of "lossy" are made mostly by people who don't understand well what is going on.... and are treating lossless and lossy as almost a binary, black/white thing.   

 

Rather than considerig MQA compression (in isolation from all the "benefits" the claim to bring, like "deblurring") to being even close to audible....  I'd consider that the output of an MQA decoder IS effectly the identical article to what is in the studio vault.

 

 

One intersting thing here is, also that while sighted/placebo can markedly help MQA  (I'm expedcting an improvement) ....  the fear of "lossy" can also run the other way for them  (I'm expecting this to sound bad).

Edited by davewantsmoore
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19 minutes ago, Sean84 said:

 

Hi Dave, is this really true though. Not according to Jussi, the HQ Player Developer:

 

https://www.computeraudiophile.com/blogs/entry/466-some-analysis-and-comparison-of-mqa-encoded-flac-vs-normal-optimized-hires-flac/

 

Yes, but it is a v. complicated discussion.

 

This post essentially has it.

 

https://www.computeraudiophile.com/blogs/entry/466-some-analysis-and-comparison-of-mqa-encoded-flac-vs-normal-optimized-hires-flac/?tab=comments#comment-1554

 

 

MQA rely on a couple of things with what they are doing:

 

1) The noise floor is not audible.   Replacing it with dither is ok.   Audio does not require high bit rates to sounds good.    For example, the coment from 2L themselves about the recordings used as some of the MQA demos, which was that 14bit was they highest amount of  dynamic range (content above the noise) that they had ever been able to present on a recording in practise  (this is more than 84dB above the noise floor of the recording environment)

 

2) Frequencies above ~20khz are not audible.... but there is a purpose to having them available in reconstructing the data in the audible range.    Actual SPL at >~20khz is inaudible.

 

 

If people don't agree with these things (especially 1), then they will not like the idea of MQA.

 

 

 

 

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34 minutes ago, Sean84 said:

 

Hi Dave, is this really true though. Not according to Jussi, the HQ Player Developer:

 

https://www.computeraudiophile.com/blogs/entry/466-some-analysis-and-comparison-of-mqa-encoded-flac-vs-normal-optimized-hires-flac/

 

 

However.   Jussi is is spot on about one big thing.   FLAC is a perfectly reasonable alternative to all of this from the perspective of data rates.

 

FLAC doesn't satisfy the use case of avoiding a (potential) resampling at playback, where the DAC doesn't support the specific rate... or where the DAC chooses to resample internally.    ie.  MQA say they can do a better job of rendering the audio, than you DAC can do resampling to it's preffered rate.  MQA contend that this resampling harms the audio.      Is this use case by MQA contentious?!   I think so - others do not.

 

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7 minutes ago, Sir Sanders Zingmore said:

But then what is MQA adding that requires hi resolution streaming ?

 

Did you misread #2?

 

There IS a purpose to having those high sampling rates (time precision) .... just no point in pumping out sound waves that oscillate faster than you can hear.

 

Which is why for example, some roll off, or noise in the reconstructed audio at > 20khz is no issue.

Edited by davewantsmoore
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15 minutes ago, davewantsmoore said:

Yes, but it is a v. complicated discussion.

 

This post essentially has it.

 

https://www.computeraudiophile.com/blogs/entry/466-some-analysis-and-comparison-of-mqa-encoded-flac-vs-normal-optimized-hires-flac/?tab=comments#comment-1554

 

 

MQA rely on a couple of things with what they are doing:

 

1) The noise floor is not audible.   Replacing it with dither is ok.   Audio does not require high bit rates to sounds good.    For example, the coment from 2L themselves about the recordings used as some of the MQA demos, which was that 14bit was they highest amount of  dynamic range (content above the noise) that they had ever been able to present on a recording in practise  (this is more than 84dB above the noise floor of the recording environment)

 

2) Frequencies above ~20khz are not audible.... but there is a purpose to having them available in reconstructing the data in the audible range.    Actual SPL at >~20khz is inaudible.

 

 

If people don't agree with these things (especially 1), then they will not like the idea of MQA.

 

 

 

 

 

Noted, but I meant to ask about your point about MQA's goal to "Distribute lossless music using less bandwidth."

 

From the link I showed it looks like MQA uses higher bandwidth? 

 

Unless I'm missing something about your last reply - apologies in advance.

 

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7 minutes ago, davewantsmoore said:

Did you misread #2?

Cmon dave you are usually more patient when explaining things :)

 

I read #2 but don't understand. How does higher sampling rates result in better time precision in the audible spectrum. 

Also, from the Archimago post on computer audiophile it looked to me as if time precision was worse (apologies if I've misunderstood that bit of his post)

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3 hours ago, Sean84 said:

Noted, but I meant to ask about your point about MQA's goal to "Distribute lossless music using less bandwidth."

From the link I showed it looks like MQA uses higher bandwidth?

 

From the link:

 

382.8/24 as FLAC = 69MB

382.8/24 resampled to 44.1/24 FLAC = 14MB

382.8/24 encoded with MQA to 44.1 FLAC = 16MB

 

MQA is 2MB bigger, because it's noise floor compresses less (because that's where MQA stores it data)

 

 

Jussi then says that to encode the original, you need ~120/18, and the FLAC encoding is 13MB.   (3MB smaller than the MQA encoded file).   This would require a resample at playback.    HQPlayer and MQA can do that without penalty, but most other players/DACs would not.

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Interesting. I'm really struggling to see what real world benefits MQA is holding over high sample rates. Pretty much the only thing I can see is the preringing of filtering which could be done with any other filters. Again the compression side is laughable in the modern bandwidth world, especially when the un-decoded MQA file is actually noisier than the redbook data based on the hqplayer article referenced above. Come to think of it, if the extra data is encoded into the existing data it has to be noisier, but then the question is whether it's audible or not. It probably isn't but if there's a way to add data without adding noise, what's the advantage? Again only bandwidth.

Edited by Ittaku
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10 hours ago, davewantsmoore said:

 

 

Jussi then says that to encode the original, you need ~120/18, and the FLAC encoding is 13MB.   (3MB smaller than the MQA encoded file).   This would require a resample at playback.    HQPlayer and MQA can do that without penalty, but most other players/DACs would not.

 

What are the perceived downsides of resampling/upsampling other than the  cpu power required?  

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