Everything you wanted to know about MQA

[KeithL]

Not really.

What we're talking about here are oversampling filters.... which mostly determine pre-ringing and post-ringing.....
In general, those are most obvious as a subtle difference in how transients sound.
(So, for example, cymbals may sound more or less harsh, and instruments which produce high frequency harmonics may sound "sharper" or "blurrier".)
In some cases, certain filters do affect the audible frequency response, but usually in the form of a subtle (or not so subtle) rolloff or boost of high frequencies.
(These are NOT the sort of filter you would use as "an EQ preset" and that's not really what they're for.)

On some DACs that offer multiple filters, one or more choices may roll off high frequencies, but that's more of a side effect than an intended adjustment of the frequency response.

Sept 22, 2017 16:06:27 GMT -5 brutiarti said:

KeithL the filters on some dacs can be equivalent to some sort of equalization presets?

[novisnick]

Oct 5, 2017 15:13:01 GMT -5 mgbpuff said:

Oct 5, 2017 12:56:20 GMT -5 novisnick said:

Just rewatched again, your seeing and hearing things! Please share with the rest of us.

1:57 " that's Trump like mean"

2:08 "the truth is, followed by may, is how populists do business"

Wow! Rather thin my friend.

[DYohn]

Partly because it aligns with my opinion, but mostly because it is from Mike Moffat, the "father" of audio DACs, founder of Theta Digital and co-founder and chief designer of Schiit Audio, I'd like to repost something he wrote on Head-Fi:


I hate to validate MQA by even answering this question, but once a year or so ain’t bad. Read the Wiki on MQA. Read it again.

1. It is lossy. It throws away perfectly good audio data.
2. There has never been an apples to apples demo of MQA vs non MQA using the same master. Ever.

The high end audio press are the only proponents of MQA
1. Face it, there is not much exciting going on in audio.
2. Perhaps due to #1 above, they in the past have advocated such unsuccessful standards as quadrophonic records, elcasets, mini discs, HDCD, DVD Audio, and most recently DSD. Why should MQA be different? Because it is lossy? Because it only appeals to the High End? Oh, you can stream I it on Tidal? How about Amazon? Spotify?

Read their patent. Google is your friend.
1. It is nice to be free to enjoy the music, right? So you could get an MQA Dac that phones home. Great, huh!
2. Oh and what about denial of playback rights?
3. You must be a huge fan of DRM, huh?

Feel a little denial of freedom? What about the musician who also pays them to record stuff their way, in technological secrecy? What about when they come out with the even more expensive Mk II model next year? Guess it even costs the artist more. Oh, and everyone on the playback end then needs a new DAC.

Oh, and I want to be the high-end press’ good little boy?
1. Oh, boy - I can send MQA my DAC with a complete engineering explanation so I may offer tithes and receive their permission to sell my DACs at their convenience and on their time? Oh, I forgot - I get their lossy tech.
2. I also get to compete with their Meridian products.

Wow - the recording artist and the engineer give up money for the MQA high end experience? The problem is it is not just a shakedown. It is an obsessive shot at controlling an entire industry. Not for me. They can suck my DAC.

You want a MQA Dac? Go buy a phuckin’ Mytek. Enjoy. Because I will never, ever, but never make one. Ever. Any questions?

[novisnick]

Oct 7, 2017 9:44:33 GMT -5 DYohn said:

Partly because it aligns with my opinion, but mostly because it is from Mike Moffat, the "father" of audio DACs, founder of Theta Digital and co-founder and chief designer of Schiit Audio, I'd like to repost something he wrote on Head-Fi:


I hate to validate MQA by even answering this question, but once a year or so ain’t bad. Read the Wiki on MQA. Read it again.

1. It is lossy. It throws away perfectly good audio data.
2. There has never been an apples to apples demo of MQA vs non MQA using the same master. Ever.

The high end audio press are the only proponents of MQA
1. Face it, there is not much exciting going on in audio.
2. Perhaps due to #1 above, they in the past have advocated such unsuccessful standards as quadrophonic records, elcasets, mini discs, HDCD, DVD Audio, and most recently DSD. Why should MQA be different? Because it is lossy? Because it only appeals to the High End? Oh, you can stream I it on Tidal? How about Amazon? Spotify?

Read their patent. Google is your friend.
1. It is nice to be free to enjoy the music, right? So you could get an MQA Dac that phones home. Great, huh!
2. Oh and what about denial of playback rights?
3. You must be a huge fan of DRM, huh?

Feel a little denial of freedom? What about the musician who also pays them to record stuff their way, in technological secrecy? What about when they come out with the even more expensive Mk II model next year? Guess it even costs the artist more. Oh, and everyone on the playback end then needs a new DAC.

Oh, and I want to be the high-end press’ good little boy?
1. Oh, boy - I can send MQA my DAC with a complete engineering explanation so I may offer tithes and receive their permission to sell my DACs at their convenience and on their time? Oh, I forgot - I get their lossy tech.
2. I also get to compete with their Meridian products.

Wow - the recording artist and the engineer give up money for the MQA high end experience? The problem is it is not just a shakedown. It is an obsessive shot at controlling an entire industry. Not for me. They can suck my DAC.

You want a MQA Dac? Go buy a phuckin’ Mytek. Enjoy. Because I will never, ever, but never make one. Ever. Any questions?

This comes to mind, and anytime someone takes an absolute stand it bothers me.

                                        

[monkumonku]

As Dyohn's recent post stated based on what is written in Wikipedia:

There has never been an apples to apples demo of MQA vs non MQA using the same master. Ever.

That is what puzzles me. The starting point from which everyone talks about is the MQA version of the music. The version that they made from the original master. Was that remixed? I assume it was. If so, then comparing the original master to the MQA remix already invalidates any comparison because it is no longer apples to apples. Anything you do from the MQA version forward has already been a modification of the mix of the original.

What is needed is to use the same master but compare it having been processed into a different format using MQA Hoodoo-Voodoo Shazam, versus not using it and then determine what differences there are. Because isn't MQA supposed to be an innovation in processing and conversion, which supposedly improves the sound? If you "improve" the sound by doing a remix of the original then that is not the same thing. And everything I have read so far is based on comparing the MQA remixed version to some other version.

Now, it can very well be that the remix MQA does is superior to the original. That's fine. But if that is the case then what is the point of doing all this nebulous additional processing down the line? If you ask me, it's a marketing ploy, no different than how Bose operates. If you do a remix or remaster of something you can make money when people buy it. But think of all the extra money you can make if you tie it in with processing hardware and software that has to be licensed - that really expands the scope of revenue generation.

People try and lend credibility to MQA by pointing out how many companies have embraced their "technology" but what does that really say? They all embraced THX, too. They will embrace anything that they think will improve their bottom line regardless of the actual technological benefits.

You can say don't knock it until you've heard it, but my beef is not with whether these MQA versions sound better, it is with whether that is because they are remixes or because the actual MQA conversion process (whatever that may be since it still seems vague) improves the sound. Those are two distinctly separate issues.

[novisnick]

I get that everyone wants to see if there’s magic, (doubtful ) or some Secret sauce, doubt that too. But Im into liking what I hear and NOT the technology behind it.

I like what I hear for the most part! And thats all that matters in the end. 😁🎶👍🥓  

Did you buy Emotiva products because of the pretty blue lights OR because it sounded good?

[hemster]

Oct 7, 2017 11:36:27 GMT -5 novisnick said:

...Did you buy Emotiva products because of the pretty blue lights OR because it sounded good?

Both!  

[novisnick]

This is a better place to start. IMHO
Its in two parts and well worth investing in the time to watch. He has included closed captioning for those that may have trouble following his English.

                      

[Casey Leedom]

You know, at this stage, even if MQA were everything it claimed I wouldn't take it. It's an intellectual property land grab for every single stage of the pipeline from production to consumer. I don't want to reward this kind of cynical evangelism. I'm voting with my wallet. The answer is no.

Casey

[geebo]

Until a meaningful comparison of MQA vs non-MQA is done using the same exact masters then there is no reason for me to buy into it. Why after all this time has it not been done? Is it something MQA doesn't want us to know ie there is no difference or the non-MQA version actually sounds better? No one knows except perhaps the MQA people.

[LCSeminole]

Oct 7, 2017 9:44:33 GMT -5 DYohn said:

1. It is lossy. It throws away perfectly good audio data.
2. There has never been an apples to apples demo of MQA vs non MQA using the same master. Ever.

I'll never buy into MQA because of #1. For me, lossless is the only way to go, period. #2 just adds to my skepticism of MQA.

[monkumonku]

Oct 8, 2017 9:27:00 GMT -5 geebo said:

Until a meaningful comparison of MQA vs non-MQA is done using the same exact masters then there is no reason for me to buy into it. Why after all this time has it not been done? Is it something MQA doesn't want us to know ie there is no difference or the non-MQA version actually sounds better? No one knows except perhaps the MQA people.

And they ain't talkin'!!! It's as if they had some sort of restrictive filter put on them that compressed the explanation. It seems to have lost something.

[novisnick]

Have all,of you seen how it’s actually triple folded and decoded?

[monkumonku]

Oct 8, 2017 14:41:55 GMT -5 novisnick said:

Have all,of you seen how it’s actually triple folded and decoded?

Let's say that I have a picture (picture A). I then use Photoshop to alter that picture, to make picture B. It looks better than the original picture B because of the alterations made.

Then I fold picture B once, twice, then three times so that it has been triple folded. Then I unfold the picture back to how it originally was, so it has been triple folded and then triple unfolded.

Then I compare picture B to picture A and picture B looks better.

So it follows that it must be the triple folding and unfolding I did that makes picture B a better picture, right? The folding process is great!

***

What it SHOULD be is that I take picture A, make an exact copy of it that hasn't been altered in Photoshop, then take that and fold it once, twice, three times then I unfold it back to the original. And then I compare it to the one that hasn't been folded at all. Then if the folded one looks better than the original, it follows that the folding process made it look better.

[novisnick]

Oct 8, 2017 15:04:21 GMT -5 monkumonku said:

Oct 8, 2017 14:41:55 GMT -5 novisnick said:

Have all,of you seen how it’s actually triple folded and decoded?

Let's say that I have a picture (picture A). I then use Photoshop to alter that picture, to make picture B. It looks better than the original picture B because of the alterations made.

Then I fold picture B once, twice, then three times so that it has been triple folded. Then I unfold the picture back to how it originally was, so it has been triple folded and then triple unfolded.

Then I compare picture B to picture A and picture B looks better.

So it follows that it must be the triple folding and unfolding I did that makes picture B a better picture, right? The folding process is great!

***

What it SHOULD be is that I take picture A, make an exact copy of it that hasn't been altered in Photoshop, then take that and fold it once, twice, three times then I unfold it back to the original. And then I compare it to the one that hasn't been folded at all. Then if the folded one looks better than the original, it follows that the folding process made it look better.

I love ya like a broha! But im calling BS
you havent spent any time looking into how its done, your ass/u/me  ing!fact and assumptions.

                                      

[garbulky]

Actually there is a place to compare the MQA and non MQA versions of the same file. It was posted in this thread. It was a free file site too

[Casey Leedom]

Interesting commentary on MQA from Bruno Putzeys Linkwitz Lab's blog quoted from Bruno's Facebook posting on October 21, 2017.  Bruno is the inventor of the Ncore Class D Amplifiers at Hypex, founder of Mola Mola, Kii Speakers, etc.

This isn't a prelude to suddenly becoming active on FB but I felt I had to share this.

Yesterday there was an AES session on mastering for high resolution (whatever that is) whose highlight was a talk about the state of the loudness war, why we're still fighting it and what the final arrival of on-by-default loudness normalisation on streaming services means for mastering. It also contained a two-pronged campaign piece for MQA. During it, every classical misconception and canard about digital audio was trotted out in an amazingly short time. Interaural timing resolution, check. Pictures showing staircase waveforms, check. That old chestnut about the ear beating the Fourier uncertainty (the acoustical equivalent of saying that human observers are able to beat Heisenberg's uncertainty principle), right there.

At the end of the talk I got up to ask a scathing question and spectacularly fumbled my attack*. So for those who were wondering what I was on about, here goes. A filtering operation is a convolution of two waveforms. One is the impulse response of the filter (aka the "kernel"), the other is the signal.

A word that high res proponents of any stripe love is "blurring". The convolution point of view shows that as the "kernel" blurs the signal, so the signal blurs the kernel. As Stuart's spectral plots showed, an audio signal is a much smoother waveform than the kernel so in reality guess who's really blurring whom. And if there's no spectral energy left above the noise floor at the frequency where the filter has ring tails, the ring tails are below the noise floor too.

A second question, which I didn't even get to ask, was about the impulse response of MQA's decimation and upsampling chain as it is shown in the slide presentation. MQA's take on those filters famously allows for aliasing, so how does one even define "the" impulse response of that signal chain when its actual shape depends on when exactly it happens relative to the sampling clock (it's not time invariant). I mentioned this to my friend Bob Katz who countered "but what if there isn't any aliasing" (meaning what if no signal is present in the region that folds down). Well yes, that's the saving grace. The signal filters the kernel rather than vice versa and the shape of the transition band doesn't matter if it is in a region where there is no signal.

These folk are trying to have their cake and eat it. Either aliasing doesn't matter because there is no signal in the transition band and then the precise shape of the transition band doesn't matter either (ie the ring tails have no conceivable manifestation) or the absence of ring tails is critical because there is signal in that region and then the aliasing will result in audible components that fly in the face of MQA's transparency claims.

Doesn't that just sound like the arguments DSD folks used to make? The requirement for 100kHz bandwidth was made based on the assumption that content above 20k had an audible impact whereas the supersonic noise was excused on the grounds that it wasn't audible. What gives?

Meanwhile I'm happy to do speakers. You wouldn't believe how much impact speakers have on replay fidelity.
________
* Oh hang on, actually I started by asking if besides speculations about neuroscience and physics they had actual controlled listening trials to back their story up. Bob Stuart replied that all listening tests so far were working experiences with engineers in their studios but that no scientific listening tests have been done so far. That doesn't surprise any of us cynics but it is an astonishing admission from the man himself. Mhm, I can just see the headlines. "No Scientific Tests Were Done, Says MQA Founder".

Casey

[Loop 7]

Nov 9, 2017 13:52:06 GMT -5 Casey Leedom said:

Interesting commentary on MQA from Bruno Putzeys Linkwitz Lab's blog quoted from Bruno's Facebook posting on October 21, 2017.  Bruno is the inventor of the Ncore Class D Amplifiers at Hypex, founder of Mola Mola, Kii Speakers, etc.

Yeah, very interesting.

He brings up an issue that seems to be all but ignored, loudness and MQA. The MQA champions don't seem interested in discussing it.

Many of the MQA encoded albums I've heard on TIDAL are compressed to heck and really loud. Sure, they sound slightly less fatiguing but, come on! Since so many remastered and new recordings are brick-walled, why waste a moment of time encoding them? Until some ethics are in play for re-releasing albums, it seems like a huge waste.

There are, of course, exceptions. I've been listening to some of the remasters mixed by Steven Wilson and some are just incredible.

[novisnick]

Nov 9, 2017 21:12:03 GMT -5 Loop 7 said:

Nov 9, 2017 13:52:06 GMT -5 Casey Leedom said:

Interesting commentary on MQA from Bruno Putzeys Linkwitz Lab's blog quoted from Bruno's Facebook posting on October 21, 2017.  Bruno is the inventor of the Ncore Class D Amplifiers at Hypex, founder of Mola Mola, Kii Speakers, etc.

Yeah, very interesting.

He brings up an issue that seems to be all but ignored, loudness and MQA. The MQA champions don't seem interested in discussing it.

Many of the MQA encoded albums I've heard on TIDAL are compressed to heck and really loud. Sure, they sound slightly less fatiguing but, come on! Since so many remastered and new recordings are brick-walled, why waste a moment of time encoding them? Until some ethics are in play for re-releasing albums, it seems like a huge waste.

There are, of course, exceptions. I've been listening to some of the remasters mixed by Steven Wilson and some are just incredible.

Ill read any and all information I can find about MQA, no matter what! With that said, I like what I hear!  Loudness wars are long gone IMHO. 
SO, Whats to discuss? 

[mgbpuff]

I agree with novisnick. I'm reading all I can about the MQA process. It is very steeped in esoteric mathematics and hard to follow (especially for a person who had his last mathematics courses some 45 years ago). It seems to me that Bruno Putzey is an Edison type and Bob Stuart is a Tesla type. Never shall the twain agree! That said, my go to recordings to evaluate different systems are some of Sinatra's better albums because of the familiarity with the character of his voice. The MQA versions I heard from Tidal (Wee Small Hours Of The Morning) are the clearest most natural sounding I have ever heard. This is on my Cary AIOS / NHT 2.5 system, a minimum stereo system with older, but competent speakers.