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

[raistlin65]

I am not worried about sending him traffic. If traffic helps advance the topic, so be it. People look to me for consistency, constantly asking why I am not at war with MQA. I want them to know that they themselves are championing a pure subjectivist that puts little to no value to objective audio testing and research.

I don't think anybody's wondering why you aren't "at war with MQA."

At this point, I imagine people are wondering why you appointed yourself MQA's proxy?

This has gone beyond just a technical critique of what Golden One has said about MQA. Now you're doing a hit job on him.

Meanwhile, you've repeatedly stated how MQA works as if it is fact, even though many of their claims remain unverified by independent measurements. A lot of people consider ASR as the place where manufacturer claims are greeted with skepticism until they can be verified.

You've been dismissive of the notion that MQA's marketing is misleading. You've shown apathy for the closed format concerns. Oh, and then there's the untenable claim that MQA is free to users.

So no. I don't think people are wondering why you aren't fighting with MQA. You've been been busy taking on almost every critique of MQA.

On the other hand, I do think people are probably wondering why you didn't decide to stay more neutral? Showing skepticism of a manufacturer's claims until they are verified is not "going to war."

 

[DimitryZ]

No. If his ONLY talks about MQA not being mathematically lossless there would be NO drama.
He managed to dragged MQA themselves, TIDAL, Topping, SMSL, Amir under the water. Insanely amount of BS claims, accusations without any evidence.
He uses MQA not being lossless as a shield to defend anything not related to MQA being lossless or not.
People just can't comprehend the fact we can agree on something while not agree on something at the same time?
We all agree that MQA is not mathematically lossless. Everything being discussed here is anything other than that.

You are so right.

This has been known since MQA's inception and certainly since Archimago's analysis in 2017.

That this is news at all in 2021 is rediculous.

 

[DimitryZ]

I don't think anybody's wondering why you aren't "at war with MQA."

At this point, I imagine people are wondering why you appointed yourself MQA's proxy?

This has gone beyond just a technical critique of what Golden One has said about MQA. Now you're doing a hit job on him.

Meanwhile, you've repeatedly stated how MQA works as if it is fact, even though many of their claims remain unverified by independent measurements. A lot of people consider ASR as the place where manufacturer claims are greeted with skepticism until they can be verified.

You've been dismissive of the notion that MQA's marketing is misleading. You've shown apathy for the closed format concerns. Oh, and then there's the untenable claim that MQA is free to users.

So no. I don't think people are wondering why you aren't fighting with MQA. You've been been busy taking on almost every critique of MQA.

On the other hand, I do think people are probably wondering why you didn't decide to stay more neutral? Showing skepticism of a manufacturer's claims until they are verified is not "going to war."

Stop.

Amir's explanations re MQA are just fine.

Most of your misconceptions should have been laid to rest by Archimago's 2017 analysis.

There's no technical controversy here, except in your mind and GO's botched tests. None of this is actually real. This is a four year old nothing burger.

Accusations of paid shilling are wrong, scurrilous and disgusting. I have been accused of such on PFM (with moderators acceptance and bans of my responses) and I I'm in defense/aerospace business, FCS! I literally don't need the money - not that I would accept it if offered (wasn't).

 

[amirm]

I don't think anybody's wondering why you aren't "at war with MQA."

Then you haven't read this thread, the one before it and the same one on every other forum!

At this point, I imagine people are wondering why you appointed yourself MQA's proxy?

Those people can't read. I have not advocated MQA in any form or fashion. As I have said 1000 times, I am here to correct misinformation posted about it. If something is wrong, it needs to be corrected. That is what objectivity is about. Caring about truth and reality. You can't turn a blind eye to someone saying wrong things about MQA just because you hate it too.

You've been dismissive of the notion that MQA's marketing is misleading. You've shown apathy for the closed format concerns. Oh, and then there's the untenable claim that MQA is free to users.

I have never seen so many people lose sight of what is relevant and what is not. Two major content distributors have announced high-res audio without MQA and you still worry what marketing this little company has done? You have been manipulated into becoming foot soldiers to fight someone else's battle and you don't even realize it.

As to closed formats, you all consume it a million times a day so don't come complaining about that. You use an iPhone? Can you download your favorite apps and pay for it how you want? You can't right? You play netflix? It has DRM and encryption. You watch cable to Satellite TV? Ditto wih their conditional access and closed terminals. So don't tell you care about closed formats. You could care less if you weren't agitated to have this fight over MQA.

 

[amirm]

Adding on, there is also serious confusion regarding closed formats. Closed formats can be dangerous if they are persistent. With MQA, almost all of it is consumed using streaming via Tidal. It is all transient. I have no stored content in Tidal. If MQA goes away, I have no exposure. Tidal would switch to non-MQA and all of my playlist and library items in Roon will play using whatever their new format is. Since all MQA DACs also play non-MQA content as well, there is no exposure there either.

This is all also very threatening to MQA. They could be wiped out of existence with one decision in a boardroom at Tidal. There is no "stickiness" to drive continued adoption. One jolt and the format is done.

 

[DimitryZ]

Adding on, there is also serious confusion regarding closed formats. Closed formats can be dangerous if they are persistent. With MQA, almost all of it is consumed using streaming via Tidal. It is all transient. I have no stored content in Tidal. If MQA goes away, I have no exposure. Tidal would switch to non-MQA and all of my playlist and library items in Roon will play using whatever their new format is. Since all MQA DACs also play non-MQA content as well, there is no exposure there either.

This is all also very threatening to MQA. They could be wiped out of existence with one decision in a boardroom at Tidal. There is no "stickiness" to drive continued adoption. One jolt and the format is done.

True enough and it would be sad. We will revert back 40 years with no lessons learned.

 

[KSTR]

You partially answer your own question there. There are two misunderstandings here:

1. That the encoder needs to handle all cases perfectly. It does not. The lossy codec that was used to encode that video likely went nuts and distorted that clip. But either that doesn't matter in this kind of content. Or falls in the category of, "yes, it doesn't produce good quality in 0.0001% of the clips. So what?"

A true mathematical lossless codec could fail on this as well and just spit out the source instead of compressing anything. That would be a failure to do its job but people don't notice.

OP wants such pathelogical clips to produce correct output. That is not in the cards for any compression algorithm.

2. That something that sounds noise like to a human, must be the same as test signals used by OP. You just can't make such a determination by ear or intuition. You need to measure. I just did that with the clip you post in youtube. I recorded about a minute of it and did a full analysis of it:

View attachment 133047

We see that the spectrum nicely drops off as frequencies increase -- precisely what MQA algorithm is counting on. We have 50 dB reduction in level at 20 kHz that we have at lowest frequency.

The start of this clip is far more noise like so let's analyze that:

View attachment 133048

Again, the same trend. There is no equal spectrum and certainly not one that extends beyond 20 kHz. I don't care what you synthesized I am pretty sure you did not use one that filled the ultrasonics with same level.

Remember, if you had flat response, you would blow up your tweeter and your ears instantly at any decent listening level! So if you could listen to it with the little tweeters in your speakers relative to the massive size of the woofer, you were not generating "pure white noise." If you do create such content, it will not be playable or listenable. What MQA then does to it is not material. It could pump a bunch of noise of its own and you wouldn't know the difference.

Conclusion
It is OK to have corner cases where an encoder can't handle the content. This is the case with just about any compression algorithm. Pathological cases are called that for a reason. If a test signal falls in this category, then it cannot be used to judge the quality of the codec if it doesn't represent 99.999% of the music out there.

Second, you need to analyze the spectrum to know. What appears noise-like is not what it seems. And if you did create such crazy signals, it would be damaging to many things with MQA being the least of your worries.

We already know that MQA can handle full-scale high-frequency content as long as it is below 22.05/24k. Otherwise it would not be capable of being compatible to 44.1/48k-LPCM (16 or 24bit).

The interesting question therefore is how it handles the folded content exactly and where the limits are. The "Triangle" is misleading and not applicable as it is long-term average spectrum and thus only seems to show general channel capacity, not transient capabilities.
I would think the maximum allowable burst level for HF signals is a gentle slope from 22/24k downwards because if it weren't, MQA could not even handle a hard cymbal hit in a modern recording with SR >= 88.2k, assuming mics have been used that don't brickwall at 20k (and no mic does except the few ones with built-in ADC). OTOH, 40kHz at full blast cannot be handled.

Summing it up, what is missing (or at least I haven't found it, not looking that hard I admit) is a clear engineering description of what signal is really allowable, basically the corner points of the algorithms used to catch problematic content, time-energy stuff. As mentioned, the Triangle is not showing this.

 

[DimitryZ]

And now you’re simply jealous, my friend! We absolutely do! Unless the offer carries a confidentiality clause, of course.

And that’s how some of us have grown from a car allowance twenty-some years ago to a personal helo, corporate jets, and Mediterranean-based corporate yachts (did your VP mentioned those to you?)… As for my name, it’s Bond, James Bond. James H. Bond.

But what any of it has to do with “I published music on tidal to test MQA”!? So, I’ll let it hang here for a bit - ‘for your eyes only’, and then self-moderate it away…

You need to speak to your therapist...on your yacht or helicopter or spaceship or whatever.

And you need a conversation with your spellchecker.

 

[DimitryZ]

We already know that MQA can handle full-scale high-frequency content as long as it is below 22.05/24k. Otherwise it would not be capable of being compatible to 44.1/48k-LPCM (16 or 24bit).

The interesting question therefore is how it handles the folded content exactly and where the limits are. The "Triangle" is misleading and not applicable as it is long-term average spectrum and thus only seems to show general channel capacity, not transient capabilities.
I would think the maximum allowable burst level for HF signals is a gentle slope from 22/24k downwards because if it weren't, MQA could not even handle a hard cymbal hit in a modern recording with SR >= 88.2k, assuming mics have been used that don't brickwall at 20k (and no mic does except the few ones with built-in ADC). OTOH, 40kHz at full blast cannot be handled.

Summing it up, what is missing (or at least I haven't found it, not looking that hard I damit) is a clear engineering description of what signal is really allowable, basically the corner points of the algorithms used to catch problematic content, time-energy stuff. As mentioned, the Triangle is not showing this.

They posted it recently. Please refer to their answer.

 

[amirm]

The interesting question therefore is how it handles the folded content exactly and where the limits are. The "Triangle" is misleading and not applicable as it is long-term average spectrum and thus only seems to show general channel capacity, not transient capabilities.

Spectrum they post is peak values, not average. So if they accommodate the worst case situation, they should be good.

 

[KSTR]

Spectrum they post is peak values, not average. So if they accommodate the worst case situation, they should be good.

As I've shown in a previous post, pretty much any modern mastering shows spots where the signals are way outside the Triangle. At 10kHz only some -20dBFS would be allowed according to that, which is obviously not correct.

 

[KSTR]

They posted it recently. Please refer to their answer.

Care to share a quick link?

 

[lucretius]

All of this has been addressed repeated in this thread including in the last few days. Read them before repeating myths about dynamic range. Or at least watch this video of mine:

Thank for the Video. Ineresting. It addresses how loud sound can be. Now I Just need to figure out how loud the noise floors are (of equipment, of a typical room etc.)

 

[DimitryZ]

Care to share a quick link?

It has been posted upthread multiple times. Google is also helpful here.
And OP is getting paid by your click.

 

[Slayer]

As I some what eluded to in an earlier post. This is, or should I say has, fully turned into and standoff of Ego's going round and round. No one want's to admit they may be wrong, or might be misinterpreting things being said, or the manner in which they are written, nor taking things out of context for which they were intended.

This thread now seems to be nothing more than a battle of wit's ( which i assume many are at their ends) ( which up to a point is fine, eventually one should be able to bow out gracefully ). Some are still stuck with my example or explanation is better than yours and if you can't or don't understand my explanation then you just don't get it and your explanation makes no sense. GRRRRRRRR . Yet many people are pretty much saying the same thing,( over and over and over ) only choosing to word it differently yet with the same inference. Things are now turning into petty little squabbles that have nothing to do with the topic of this thread or they find it incomprehensible that they could possibly be wrong.

Maybe it's time we all take a breather and step back for awhile. Hopefully, maybe, doubtfully, someone from MQA has the courage to step-up and post a comprehensive response ( detailed and precise, that leaves no room for misinterpretations ) that will put an end to all this bickering.

 

[amirm]

Thank for the Video. Ineresting. It addresses how loud sound can be. Now I Just need to figure out how loud the noise floors are (of equipment, of a typical room etc.)

See the references in my article here: https://www.audiosciencereview.com/forum/index.php?threads/dynamic-range-how-quiet-is-quiet.14/

 

[DimitryZ]

As I some what eluded to in an earlier post. This is, or should I say has, fully turned into and standoff of Ego's going round and round. No one want's to admit they may be wrong, or might be misinterpreting things being said, or the manner in which they are written, nor taking things out of context for which they were intended.

This thread now seems to be nothing more than a battle of wit's ( which i assume many are at their ends) ( which up to a point is fine, eventually one should be able to bow out gracefully ). Some are still stuck with my example or explanation is better than yours and if you can't or don't understand my explanation then you just don't get it and your explanation makes no sense. GRRRRRRRR . Yet many people are pretty much saying the same thing,( over and over and over ) only choosing to word it differently yet with the same inference. Things are now turning into petty little squabbles that have nothing to do with the topic of this thread or they find it incomprehensible that they could possibly be wrong.

Maybe it's time we all take a breather and step back for awhile. Hopefully, maybe, doubtfully, someone from MQA has the courage to step-up and post a comprehensive response ( detailed and precise, that leaves no room for misinterpretations ) that will put an end to all this bickering.

The only controversy is in your mind.

This has long been settled by Archimago's analysis from 4 years ago.

Today, it's a nothing burger on top of a nothing burger.

 

[KSTR]

It has been posted upthread multiple times. Google is also helpful here.
And OP is getting paid by your click.

What exact keywords should I google for? This is real and serious question.
In search of a graph that plots maximum allowable level in the source content vs. frequency. And no, not the triangle....

 

[Raindog123]

This has long been settled by Archimago's analysis from 4 years ago.

As tonight is the night of demystifying everything at once, can you have a shot at my three long-overdue questions? Here they are:

MQA Deep Dive - I published music on tidal to test MQA | Page 93 | Audio Science Review (ASR) Forum

Hopefully, they will help us to knock-off that final one "Why do consumers need MQA (both 24/48 and 'MQA-CD') if we already have 24/48 (and can have 20/96) open-standard PCM/FLAC"?

Thanks in advance, @DimitryZ. Or should we call you 'Bob'? (Sorry, Twin Peaks is still my all-time favorite!)

 

[DimitryZ]

What exact keywords should I google for? This is real and serious question.
In search of a graph that plots maximum allowable level in the source content vs. frequency. And no, not the triangle....

https://bobtalks.co.uk/a-deeper-look/all-that-glitters-is-not-golden/#