MQA Deep Dive - I published music on tidal to test MQA

[amirm]

Yes, we have been harmed in the consumer sense.
We bought music, that: (1) They claimed was lossless, (2) Came directly with special care from the artist, (3) Undid some artifacts from bad AD conversion, etc. etc. And it was all a lie. That is the definition of consumer harm.

Which album did you buy? And why do you say "we?" You can't speak for yourself?

 

[jensgk]

Which album did you buy?

I have written about it here:
https://www.audiosciencereview.com/...n-tidal-to-test-mqa.22549/page-90#post-763455
and here:
https://www.audiosciencereview.com/...n-tidal-to-test-mqa.22549/page-94#post-763958

And why do you say "we?" You can't speak for yourself?

Read the threads about the subject on the internet. I am obviously not the only one feeling deceived.

 

[PierreV]

Which album did you buy? And why do you say "we?" You can't speak for yourself?

This is really what I don't understand. What justifies a reflex snarky response to @jensgk who, as a legitimate customer, was obviously disappointed and even got an answer from the artist's side... and not an insignificant artist either?

 

[Mountain Goat]

Something you didn't mention but I value is elegance in efficient coding of music. I have always considered PCM format to be highly wasteful. As a person who has spent decades optimizing technology, it seems like such a poor solution. Going from 44.1 kHz to 88.2 kHz doubles the data rate yet there is hardly any musical information to be gained from that doubling. In that regard, MQA's approach of noticing the statistical aspects of music and encoding that is appealing to me. It is simply neat!

Folks expect me to operate from their vantage view, but I can't. I have to operate from my own with all of my experiences and sense of fairness and evenhandedness about the topics being discussed.

I'm trying to learn here, MQA is better than PCM at higher sampling rates?

 

[muslhead]

This is really what I don't understand. What justifies a reflex snarky response to @jensgk who, as a legitimate customer, was obviously disappointed and even got an answer from the artist's side... and not an insignificant artist either?

Totally unnecessary and disrepectful but i guess what owning the website allows you to do. Sad, really

 

[dmac6419]

This is really what I don't understand. What justifies a reflex snarky response to @jensgk who, as a legitimate customer, was obviously disappointed and even got an answer from the artist's side... and not an insignificant artist either?

He brought a album from bandcamp,not from a major label,maybe he didn't know how to ask for the non mqa version

 

[dmac6419]

Totally unnecessary and disrepectful but i guess what owning the website allows you to do. Sad, really

It has nothing to do with owning the forum, grow up

 

[muslhead]

It has nothing to do with owning the forum, grow up

Thank you for your intellectual reply, your mommy must be proud

 

[Doodski]

This thread is going further into a spiraling mess with near every comment now. ( This thread and the other MQA thread combined.)

 

[levimax]

On a more positive note I did learn 2 things about MQA today:

1. MQA is a cool lossy codec (even though it is not needed for anything)

2. MQA's plans for world domination will most likely go down in flames (Not sure Mr. Dorsey believes that though)

 

[Raindog123]

I'm trying to learn here, MQA is better than PCM at higher sampling rates?

No - from the information capacity point of view - MQA is significantly worse, as at higher sampling rates (ie after its core unfold) MQA can represent only a small fraction of higher-frequency (‘ultrasonic‘) spectrum. While a higher-sampling-rate PCM does it fully, naturally. And even the feasibility of this ‘small fraction of spectrum’ is questioned by signal-processing algorithm experts. (Pointing out that while MQA’s ‘triangular’ spectrum is a nice visual illustration in frequency domain, performing such PSM decoding in time domain is not feasible in the near-real-time of playback.) But those are ‘opinions’, meanwhile - if exists - the encoding/decoding algorithm is kept secret, and its performance test results are not offered…

At the same time, MQA’s position is that this - the diminished ability of MQA encoding to carry ultrasonic information - is irrelevant and even by-design, as ‘only a small amount of music information exists at ultrasonic frequencies - due to significantly reduced level and dynamic-range of real music there.’ This might be true - but it makes MQA’s algorithm (again, if it actually works) at best equal to PCM.

 

[Hai-Fri. Audio]

I must admit, I've probably enjoyed this food fight a little too long... but I think this soap has gone on long enough and I'm starting to scream at the characters on screen so I'm going to say my piece and... peace.

I've been lurking on here for a long time. Ok, not that long... But long enough to be in possession of an okto dac8 stereo. That's right, slow pokes...

Anyways, my gosh... where do we start?

1. the entitlement of some commenters

This is really what I don't understand. What justifies a reflex snarky response to @jensgk

Really? Have you waded through all the cr*p that Amir has had to put up with the last few days/weeks? I'm surprised he still insists on trying to educate people so hellbent on being reactionary instead of understanding the details and the respecting the very consistent methodology used on this forum to arrive at scientifically grounded conclusions invaluable to all of us gear-heads, and which is essentially FREE.

Please, go through this forum and really understand what kind of service Amir has provided all of us. Now, put yourself in his shoes... Imagine building your career, reputation, resume, knowledge for decades, then sharing that wealth of knowledge and expertise ESSENTIALLY FOR FREE. People like @jensgk have been commenting with pure snark through out this thread and elsewhere, and still Amir responds with factual corrections where they are deserved. That is a supreme amount of patience compared to yours truly.

2. the refusal of some commenters to see each point/claim as being independent and nuanced. so many people just want to construct a false dichotomy and then bash on the opposing team.

I hear you and read the criticism elsewhere from time to time. Given a choice of making a few detractors happy and being on the right side of correct technology understanding, I take the latter. My ethics in upholding what science and engineering say is far more important than getting people to like me/ASR.

It seriously hurts me to have to see Amir having to defend himself in this manner after all he's done for us. He even has to clarify his well documented position on MQA to reactionaries who clearly have not gone through enough of the material in this forum before deciding that Amir is the bad faith actor. Rational commenters like @Jimbob54 have been trying to nudge the discussion in the right direction but keep getting trampled over and dismissed by defensive reactionaries... What an unfortunate mess.

And why?
Here's my hot take: Because so many of them, like me, were so seduced by OP's fancy looking graphs and high-falutin manners that we completely abandoned any notion of critically assessing their methodology. And now our insecurities are causing some of us to not accept we had been misled.

Maybe OP did arrive at correct conclusions. Maybe MQA is not lossless at all - personally I'd like to hear more from Amir about the distinction between mathematical and perceptual lossless. Maybe MQA is *ss and they're right it should be binned. But, arriving accidentally at a correct assertion does not mean your methodology was correct. I feel so bad for Amir, a certified insider expert, who keeps on having to beat that point into the ground for snarky know it alls more interested in defending their own egos than constructing a fact based, logical discussion.

Seriously, if people weren't so invested in their own pride, they'd have all immediately realized who OP truly is after the revelation of the slander they had been spreading in other forums... which bring us to

3. THE FRIGGIN SLANDER. HOW THE HELL IS THERE SO MUCH ANGER HERE TOWARDS AMIR FOR BEING SNARKY AND NOT NEARLY THE SAME LEVEL OF VITRIOLE FOR OP's PETTINESS AND SELFISHNESS??

I know Amir is a big boy and he has no worries about his professional reputation being ruined by some up start bad faith actor. What I see as being so egregious though is that this dingbat has done a potentially massive disservice to anyone who has come across this food fight and arrived at the wrong conclusion that Amir is the one with selfish intentions. Amir has done his utmost to create a space where objectivity can exist in this snake-oil world, he's done this while balancing the forum's independence alongside policing misinformation. And now many having adopted the view that ASR is a dictatorship and Amir its tyrant... Seriously, am I the only one heartbroken for Amir here??

Essentially, OP has sowed distrust for and discord within the ASR community... reducing its efficacy and reach as a voice of truth and reason... just so they can get one over the people who called them out for having no technical nous... now they have a legion of angry fanboys destroying Amir's reputation... they've done every audiophile/gear-head who puts any value in scientific objectivity a disservice. and for what? sigh...

Initially, when OP's methodology was called out, I was willing to believe that OP had approached their experiment in good faith but was just unqualified and ignorant - things which NO ONE should be vilified for. We are, most of us, ignoramuses here... let's be real.

But after the revelation of such despicable actions I find it harder, by the minute, to believe that any of OP's actions were in good faith to begin with... Hearing them describe the sonic differences and qualities of different DACs has also compounded my skepticism.

@amirm Professor M, (may I call you professor M?) I wish us smoove-brained audio people you've educated so much could do more to help you stem this tide of nonsense but we are of limited value against such single minded hatred. In spite of all the time lost on this tangent, I'm sure truth and reason will win out in the end. Thanks for all you do, professor : D

 

[amirm]

I have written about it here:
https://www.audiosciencereview.com/...n-tidal-to-test-mqa.22549/page-90#post-763455

You think you got harmed? No, *I* just got harmed to the tune of nearly $20!!! Read on.

I looked up the album you bought on Tidal. It is available and it is indeed in MQA. I went to capture its spectrum as it played and was very surprised to see the brick wall above 22 kHz! So I got curious as to what the original 96 kHz version looked like. Fortunately one of my favorite high-res stores, Prostudiomasters had it:

Notice how they sell both the MQA and non-MQA versions. Cough up the money and buy the album. The non-MQA is indeed, non-MQA:

This is what the spectrum of the third track looks like (similar to tracks 1 and 2):

Son of gun! The actual (live) recording is at 44.1 kHz but is somehow mixed into a high-res envelop. We know this because some noise has been added there including that one peak at nearly 48 kHz.

The most shocking part is who mastered this: the famous Bob Ludwig!!! From the credits: "Mastered by Robert C. Ludwig "

Un.... believable. This is like buying a $1000 DAC from a famous designer and finding an Apple dongle in there!

You see where the real battleground is? We need to get the masters cleaned up and have them released without loudness compression. That is the battle we should put our energy toward. Not these little squabbles over MQA.

I am going to go on hot dogs and water dinners for the next few days to make up for the $20 loss on this....

 

[ebslo]

(emphasis added)

Eh, no. MQA in that graph is saying that will encode and deliver everything that is in that music clip as defined by its peak signal at every frequency. And they even encode more than they need with that guard band.

That they don't encode empty space (CD rectangle or otherwise) that is not used by said music is of no concern to any unless you want to burn bits to hold nothing.

Does everybody understand this? It is key to their response. They are saying that their format is "lossless" because they encode the music and give it all the bits it needs including its ultrasonic spectrum.

The only argument against them then is that they are not lossless because they don't encode empty space. Which is what OP attempted to do (filled the empty space and then wondered why it couldn't encode it).

No, I don't quite understand that yet. I think I understand the part about only storing the small region of the ultrasonic information space that is occupied by music that fits their statistical model, but am still unclear about the region in which they store it. In your video you showed that the noise floor in the upper extent of the audible band was raised in the MQA encoded file. That analysis was on the non-unfolded content. Do you know whether the full unfolding/decoding process restores the original noise floor and musical data in this region of the audible band along with the ultrasonic musical data, or only the ultrasonic musical data?

 

[amirm]

(emphasis added)

No, I don't quite understand that yet. I think I understand the part about only storing the small region of the ultrasonic information space that is occupied by music that fits their statistical model, but am still unclear about the region in which they store it. In your video you showed that the noise floor in the upper extent of the audible band was raised in the MQA encoded file. That analysis was on the non-unfolded content. Do you know whether the full unfolding/decoding process restores the original noise floor and musical data in this region of the audible band along with the ultrasonic musical data, or only the ultrasonic musical data?

I do not as I have not done any testing of decoded MQA content. Hope to do that soon.

 

[ebslo]

You think you got harmed? No, *I* just got harmed to the tune of nearly $20!!! Read on.

I looked up the album you bought on Tidal. It is available and it is indeed in MQA. I went to capture its spectrum as it played and was very surprised to see the brick wall above 22 kHz! So I got curious as to what the original 96 kHz version looked like. Fortunately one of my favorite high-res stores, Prostudiomasters had it:

View attachment 132505

Notice how they sell both the MQA and non-MQA versions. Cough up the money and buy the album. The non-MQA is indeed, non-MQA:

View attachment 132507

This is what the spectrum of the third track looks like (similar to tracks 1 and 2):

View attachment 132506

Son of gun! The actual (live) recording is at 44.1 kHz but is somehow mixed into a high-res envelop. We know this because some noise has been added there including that one peak at nearly 48 kHz.

The most shocking part is who mastered this: the famous Bob Ludwig!!! From the credits: "Mastered by Robert C. Ludwig "

Un.... believable. This is like buying a $1000 DAC from a famous designer and finding an Apple dongle in there!

You see where the real battleground is? We need to get the masters cleaned up and have them released without loudness compression. That is the battle we should put our energy toward. Not these little squabbles over MQA.

I am going to go on hot dogs and water dinners for the next few days to make up for the $20 loss on this....

Have you any idea what "(source)" might mean next to the MQA option? Could it mean the MQA version is the source from which the other encoding options are derived?

 

[amirm]

Have you any idea what "(source)" might mean next to the MQA option? Could it mean the MQA version is the source from which the other encoding options are derived?

No, I think it means that the source file was 24/96 but that the MQA version is different. MQA is not a recording format anyway. They would have had to capture it in analog domain and then back to digital.

 

[amirm]

Figured out what is going on. The filtering depends on what segment of the track you are playing! Clearly some of the instruments are recorded with limited bandwidth, and others not. What a mess....

 

[voodooless]

Would be interesting to see what the spectrum of the MQA core decoded version looks like, or do you have us hanging is suspense until you make a video out of it ?

How could this have been encoded anyway? Music does not behave like this.. so the encoder should definitely have thrown a tantrum

 

[amirm]

Would be interesting to see what the spectrum of the MQA core decoded version looks like, or do you have us hanging is suspense until you make a video out of it ?

I tried but it is hard because the stupid mix switches constantly from limited bandwidth to full. So asynchronous capture using Audio Precision doesn't work. I need to get a loopback driver and capture that output. Too tired tonight but will try to tomorrow.