MQA is Vaporware

[Jud]

12 minutes ago, Shadders said:

Hi Fokus,

Thanks. It was bugging me about the pre-ringing in a filter - and the apodizing filter description. I am new to the DSP area - also found some more information as well as your link. :

https://mrapodizer.wordpress.com/2011/08/16/technical-analysis-of-the-meridian-apodizing-filter/

https://www.stereophile.com/content/meridian-8082808i2-signature-reference-cd-playerpreamplifier-measurements

This is something i was not aware of - that a linear phase FIR filter had pre-ringing for an impulse response.

I have some catching up to do....

Regards,

Shadders.

 

I’ve always liked Mr. Apodizer’s explanations.

 

For a visual appreciation, have a look at impulse tests for the various filters at http://src.infinitewave.ca.

 

You’re going to have pre-ringing in a linear phase FIR filter.  First of all, you’re going to have ringing; the filter’s phase just tells you where the ringing will be.  You can minimize the ringing with a less steep filter, but that means more aliasing.

 

This is why there is oversampling (or hi res): more headroom in which to play with the aliasing-vs.-ringing parameters.

[Jud]

44 minutes ago, mansr said:

The regular and MQA versions of The Nightfly on Tidal are clearly from different masters. Comparing track 2, there are a number of differences:

• The sample rates differ, 44.1 kHz vs 48 kHz for the MQA version.
• The MQA version is 7 seconds longer.
• The MQA version is 2 dB louder, even clipping a few times.
• The polarity of the MQA version is inverted.
• The actual speeds don't quite match. In other words, they are not simply different digital downsamples from a common source.
• The speed difference fluctuates throughout the track.

I'd be inclined to say these two versions came from different tape transfers, except it's an all-digital production.

 

To think that what got music company execs off their rear ends to allow better masters of these files was MQA!  What a waste.

[Jud]

Discogs shows first CD versions in 1983.  I counted 36 digital versions (albeit these were mostly just different countries), but still, there have been at least several versions, so good luck trying to figure out the provenance of these.

[Jud]

8 minutes ago, mansr said:

That's all well and good. You still haven't given a clear answer to my question. The album was supposedly recorded digitally using some 3M equipment. Multiple tracks and overdubbing were involved. Somehow this was turned into a stereo mix that ended up on various formats including CD. Are you saying the authoritative master is an analogue tape? At the time, that would certainly be reasonable.

 

Roger Nichols, the engineer:

 

From rogernichols.com

3M Digital Mastering System
The Ry Cooder Bop Till You Drop album was the first digitally recorded pop album. It was recorded on the 3M 32-track digital recorder at Amigo studios in North Hollywood California. We booked the Village Recorder in 1981 to cut tracks for Nightfly and decided to try the 3M digital machine. We ran a Studer A-80 24-track analog machine in parallel with the 3M for the test. After the band laid down a take we performed an a-b-c listening test. The analog and digital machines were played back in sync while the band played along live. We could compare the analog machine, the digital machine, and the live band. The closest sound to the live band was the 3M digital machine. We re-aligned the Studer and gave it one more chance. The 3M was the clear winner. We rolled the Studer out into the street, (just kidding) and did the rest of the recording on the 3M 32-track machine. When it came time to mix, we mixed to the 3M 4-track machine.

The 3M 32-track used 1” digital tape and the 4-track used 1/2” digital tape. They both ran at 45 ips. I guess 3M wanted to sell you lots of tape. The digital audio was recorded at 50kHz 16bits. There were no 16bit converters in 1981, so the 3M system used a 12 bit Burr-Brown converter and 4bits of an 8bit converter as gain-ranging to produce the 16bit results. The “brick wall” analog filters on the 3M machine hand-wound coils and took up most of a circuit board. They sounded good.

The biggest drawback to the 3M system was the minimal error correction. After a couple of months working on the same piece of tape, the error count started to rise above the correctable level. There were adjustments on the front of the machine to fine tune the decoding of the data recorded on tape. You could adjust each track for the least amount of correctable errors and then transfer the tape digitally to another 3M machine. You now had a clean error-free tape to work on for a couple of months.

[Jud]

2 hours ago, mansr said:

It's still interesting due to the weird differences between the regular and MQA versions of the album. The simplest explanation is that they are different transfers from analogue tape, and we're seeing the effects of slightly different ADC clocks and fluctuations in tape speed. If no analogue master tape was involved, something much stranger has been done.

 

Either someone did a lot of work just for an MQA master, or the MQA came from one of the several existing masters.  I wonder whether, if we were to do a little more research into the various versions listed on Discogs, we would find the master MQA used among them.

 

Track lengths for SACD, DVD-A, and SHM-CD versions might show something.

[Jud]

7 minutes ago, mansr said:

The sudden jump at 182 seconds is a bit odd.

 

Restoring content that was edited out?

[Jud]

8 hours ago, firedog said:

I and some others actually did get free upgrades to higher resolution versions of some albums when they became available.

 

Yup, me too.

 

I think Charles’ point about “an otherwise well run company” is a good one.

 

The other bug for me was that the PC software they tried to incorporate into the Pono ecosystem wasn’t terribly intuitive for me to use.  Just a regular download and dragging and dropping was much simpler for adding music.

[Jud]

31 minutes ago, Bob Stern said:

The only constraint is that the ISP's realize that if they get too greedy too quickly, the public will pressure Congress to enact an net neutrality law.

 

Public pressure, that should work against corporate advertising and donors, right?

[Jud]

7 hours ago, Oddio said:

How well do you understand the MQA process, particularly the "deblurring" as they call it?

 

Rather well.  No magic.  It faces the same choice all filtering methods do: Balancing time domain and frequency domain response.  It isn't a very sophisticated filtering method, meaning that choice, that balance, is a pretty stark one; if it does well with one, it's going to do badly with the other.  The MBA folks have chosen to throw the balance way towards doing better in the time domain, meaning frequency domain performance is lousy.  This in turn means potentially audible levels of intermodulation distortion.

 

So MQA is possibly going to sound different from filtering methods that do a better job of this balance.  Many people may hear something different and be wowed, but in fact MQA stands a very good chance of producing a different but *less accurate* sound.

 

Now everything I've said so far is based on "all else being equal." However, in instances where the MQA master is a different and better master, then the quality of the master will trump any difference in filtering methods.

[Jud]

3 minutes ago, mansr said:

That's a nonsensical thing to say. Time and frequency are equivalent through the Fourier transform. What is good in one is good in the other. Some characteristics are more easily studied in the time domain, others in the frequency domain, that is all.

 

What I was trying to describe was that the sharper the cut the filter makes, and thus the less aliasing (imaging?), the more ringing occurs, and vice versa.  I have seen this described in terms of time domain vs. frequency domain response by the folks who developed the ESS chips.  Is there a way of expressing this that would make more sense?

[Jud]

Yep, I realize this.  Just that as mentioned I've seen (by more folks than ESS) "time domain artifacts" used to describe ringing, and "frequency domain artifacts" used to describe aliasing/imaging.  Thinking of time and frequency domain performance as having to be balanced also (for me at least) helps get at the concept of conjugate variables, where optimization of one necessarily means less optimization of the other.

[Jud]

12 hours ago, Charles Hansen said:

For example in every case (using mostly Redbook sources - high res sources were extremely rare back in 2009 - just a hand ful of DVD-Vs and DVD-As which were used to double-check) I found that regardless of the other filter parameters that minimum phase sounded better than linear phase. This was just one of eight or ten different filter parameters tested.

 

Hi Charles - This raises a couple of topics of interest to me.

 

I find that in my system, with the Vandersteens, I tend to favor linear phase filters.  Perhaps 25+ years of owning Vandys (yes, I would have strongly considered Avalons had I been looking at that price range ) has gotten me accustomed to a particular type of imaging that comes with linear phase throughout the chain.  Or maybe I'm just accustomed to something in linear phase filters (having owned one of the early Theta DACs for quite a while).

 

You, as you say, have long experience listening to filters.  And I very much liked the QB-9 (listening at a friend's) and Pono Player (which I still own) which I assume both resulted from your listening process.

 

Now humans are very very bad at storing sounds in memory for more than a few seconds, so any time someone does listening comparisons, that's a rather fraught sort of thing.  We might well ask what really is being compared.

 

But one thing humans are really, really good at is pattern matching. We build up recognition of these patterns with long experience and/or training.  So we can legitimately say we may be able to recognize familiar patterns in sound.

 

When I recognize a familiar pattern of sound that for me includes linear phase filters, and for you includes minimum phase filters, as what sounds "right" to us, are we recognizing accuracy, some inborn preference, or simply what fits a familiar pattern?

 

And when listeners hear MQA or something else they think is new and great, are they recognizing greater accuracy, some inborn preference, or something that breaks out of the familiar pattern of what they've heard before?

[Jud]

@Charles Hansen - Completely agree regarding "system matching."

 

Something that interests me greatly right now, that I touched on briefly in my last comment, is how we each form our notions of what makes good or accurate sound.

 

About the TADs - I've heard TADs, as well as other speakers designed by Andrew Jones, and think he is a very smart man.

[Jud]

43 minutes ago, Charles Hansen said:

I think that the thing that would actually make them the most money is to do exactly as Neil Young suggests and sell all music for the same price, regardless of resolution. It's not as if music from great artists ever cost more than music from mediocre artists. Or that music recorded by great engineers with great sound quality in great studios cost more than music recorded in someone's basement "studio" using ProTools. So why charge more for high-resolution files?

 

I think it was just because it was proven that audiophiles would pay extra for re-issued LPs or re-mastered CDs or SACDs. But that is exactly why high-res will never achieve mainstream success - unless they introduce price parity. The definition of an audiophile is a person who will pay more for better sound quality. It is a fact that only 1 person in 1000 is willing to do so. Therefore the existing high-res paradigm is simply pissing in the wind.

 

Sometimes what can appear complicated is explained so simply.  Thanks.

 

Of course hopes of this happening are nil.  The industry constantly tries to maximize profit per unit rather than looking to the health of the overall market.  If Apple hadn’t dragged them into it, the industry would still be labeling many of their biggest potential customers pirates instead of - hey! - making it convenient and cheap for people who love music to buy it.  Crazy idea, eh?

[Jud]

2 hours ago, ShawnC said:

I wish you would share more of this. 

 

To be quite fair (or even just reasonable), thousands of A+ and SoX users benefit every day from mansr’s knowledge and work bringing DSD resampling capabilities to those pieces of software.

 

I sometimes share your wish that he might lean a little more toward the helpful and a little less toward the acerbic.  But overall I must say his participation here has been much to my benefit and that of many others.

[Jud]

7 minutes ago, mansr said:

I might be more motivated to do so if I weren't so often ridiculed on the grounds of being an engineer.

 

On that score I think you give as good as you get, or to put it slightly differently, you set the terms of discussion. Many non-engineers perceive what they say as being attacked by you, and attack back.  There are certainly engineers on the site who manage to convey engineering information in a fashion that doesn’t raise hackles personally.

[Jud]

52 minutes ago, mansr said:

Sure, I too could couch established facts of maths and physics as personal opinion and play along with the notion that everything, and then some, is audible. I'm just not willing to do that since I consider such behaviour dishonest.

 

It isn’t that at all.  Both you and Charles Hansen (an engineer not shy about saying what is on his mind when it’s in disagreement with what most folks on the forum here are saying about a topic) raised the question of whether Chris should adopt a different editorial stance regarding MQA.  Charles’ way of doing so led to discussion on the matter.  Your way of doing so led to discussion of who should be taking personal offense.

[Jud]

5 minutes ago, Melvin said:

Michael nicely highlights the latest here: https://www.audiostream.com/content/mqa-ifa-2017-updates

 

The last words in that article are “Choice is good.”  I fervently hope choice remains available.  (If there are many viable choices, I personally don’t care if MQA is one of them, though their commercial viability will have to be on someone else’s dime.)

[Jud]

50 minutes ago, Miska said:

 

I personally consider MQA a DRM system very similar to how dual-layer SACDs worked. Without certified and pre-approved decoder you can only listen severely quality degraded version. Just like RedBook layer of SACD. Only with the certified and pre-approved decoder you can fully utilize the content.

 

Also SACD player digital output was limited to allow only the RedBook quality, so the hires version could only be listened through analog outputs, or sent to another decoder over protected, certified and pre-approved digital link.

 

I'm seeing the same approach pattern still. Even though MQA claims that "you can still listen to the content without decoder" is only the quality degraded version. On purpose. That doesn't remove the DRM aspect. MQA encoding doesn't save bandwidth compared to comparable quality standard FLAC either, in fact it increases bandwidth usage because for the FLAC encoder, large portion of the data becomes just plain noise due to the embedded encrypted (DRM protected) stream.

 

And DSD really only took off after it was freed from SACD's DRM. I'm quite sure record companies make more by selling plain DSD downloads instead of SACDs.

 

 

P.S. Meridian has long history on audio content DRM, starting with MLP for DVD-Audio and continuing to Blu-ray audio... There's probably still not much on the market to rip MLP encoded multichannel audio from old DVD-A discs.

 

The difference is I actually wanted to hear what was on the DSD layer of the SACD.

 

 I would not be certain record companies make more by selling downloads, although it is not unlikely.  There has been a long time to attain cost efficiencies with the distribution system for discs, not so long for downloads.  (I recall reading an analysis of the music business’s 2015 or 2016 figures that showed how much more the industry made per unit from discs vs. the equivalent amount - a dozen or so - downloads.  That of course is dealing with companies like Apple, which isn’t a factor in DSD downloads.)

[Jud]

20 hours ago, Charles Hansen said:

 

Hi Rt66,

 

Especially when the DVD-A remixes were so god-awaful. I think Mickey Hart (or whomever did those) forgot to take enough acid. They made the Grateful Dead sound like the Osmond Brothers.

 

Cheers,

Charles Hansen

 

Horses for courses - I liked that DVD-A (while thinking DVD-A versions of Tommy and Gaucho, for example, were indeed godawful).  I haven’t yet heard an MQA version I preferred to a hi res version unless the mastering was obviously different (different instrument locations, that sort of thing).  But I know folks who have, and that’s fine with me.  Why should I have a say about what they like?

[Jud]

42 minutes ago, Shadders said:

 

If it is never to be used - then why build it in ?

 

A possible reason (how probable I’ll leave for others to discuss) is legal protection.  Getting past copy protection is a big no-no under US copyright law, so even a little goes a long way in protecting your intellectual property.

 

It would be possible to employ the DRM in MQA for this purpose without regard to whether record labels or streaming services would want to use it exclusively in the market.

[Jud]

7 minutes ago, mav52 said:

" Formats like MQA make it more portable, so it’s easier to have it yourself, in your car and outside the home. So I think that’s a great opportunity,” said Morvan Boury, VP of global digital development for Sony Music.   Yep they drank the cool aid and didn't ask to see the little fine print..

 

To the contrary - in these sorts of dealings, the record companies hold the economic power, and consequently they *write* the fine print.

[Jud]

17 hours ago, Shadders said:

This is my point - DRM is in MQA since MQA want control. DRM is not there to suffice the US Government.

 

Of course.  It’s there so MQA can maintain control of *their IP*.  But that could be the less significant part of the story for the music industry and most consumers.

 

Audiophiles are a blip on the radar for the industry.  What MQA offers the industry is something perhaps better sounding than mp3 that isn’t the hi res master.  All else is icing on the cake.  

 

It will be interesting to see to what extent the industry will market MQA as something not needing special hardware for better sound, and to what extent hardware manufacturers will market MQA-ready stuff as getting you the very best sound.

 

Of course most interesting of all will be seeing how the big streaming companies, Apple, and the music buying public react.

[Jud]

5 hours ago, mcgillroy said:

 

 

So CDs now are high-rez in label talk...

 

Makes strategic sense to frame anything above MP3/AAC like that. Divide and conquer, create leverage for price differentiation when negotiating with the entities that actually bring the music to consumers.

 

Cause with all the broohah about "High-Rez not being niche" anymore it's important not to forget where the real action is:

 

"Facebook has offered music rights-holders “hundreds of millions of dollars” to permit its users to play with copyrighted tracks as soon as possible."

 

To put that in context the combined payments of all video-streaming services like Youtube, Vimeo etc to labels in 2016 were $553m.

 

https://www.musicbusinessworldwide.com/facebook-offers-music-biz-hundreds-millions-dollars-labels-publishers/

 

MQA is just another hedge by the labels in this game. They will either drop it the moment somebody like Apple/Facebook/Google/Amazon offers them a better deal with higher royalties. Not least since none of this companies will ever let MQA and it's licensing baggage + DRM into their ecosystems.

 

Else they will leave the distribution of <16/44.1 to the platformers and >=16/44.1 to streaming services they directly or indirectly control - like Deezer, Spotify and others. 

 

I think control is the point, and why the industry would only drop MQA in favor of some Silicon Valley connection if they were forced into it economically by an apathetic reaction on the part of the music buying public.

 

For years the industry has chafed under Apple’s control of the download business, and they don’t control the streaming business to nearly the extent they would like.  MQA offers a contractual situation the industry can control, since MQA doesn’t have the size to exercise any economic leverage in contract negotiations.

 

So the music industry can be expected to try to push MQA to try to free itself from Apple and gain more leverage over the big streaming services, while Apple and the big streaming services will either wait this out or develop their own alternatives.  And that appears to be exactly what’s happening.

 

Meanwhile, MQA has no economic power and controls exactly nothing other than their own IP.

[Jud]

@Michael Lavorgna, Charles and mansr and others here have some excellent technical points to make, though I agree some Internet “debate” is extremely unlikely to provide a venue where greater understanding can take place.