MQA is Vaporware

[Samuel T Cogley]

12 minutes ago, Ishmael Slapowitz said:

Jim Austin:

 

"When I played an MQA file through each of two grouped zones to both MQA-enabled DACs, both indicated that they were decoding MQA, which, according to both Roon and MQA experts I talked to, is a clear indication of bit-perfect playback. Indeed, dCS writes in the Bartók manual, "MQA decoding is not possible if the original MQA data has been changed." 

 

https://www.stereophile.com/content/dcs-bartok-da-processorheadphone-amplifier-page-2#QFfvFtGjlKGVc3zS.99

 

???? @mansr

 

 

I thought it was @FredericV who showed that changing certain bits of the payload would alter the sound, but the blue light would remain on (MQA's "authentication" effectively circumvented).  Apologies if I'm mistaken.

[Samuel T Cogley]

6 minutes ago, The Computer Audiophile said:

I agree for the most part, but almost any technology can be altered by someone in a lab, thus making the advertised "benefit" untrue. 

 

It can be objectively stated that the "authentication" can be easily circumvented.  The practicality of this is not relevant to the fact that the "authentication" is weak.

[Samuel T Cogley]

Just now, The Computer Audiophile said:

I can also easily change your 4K tv stream to 3.999K, so Netflix should stop advertising 4K?

 

Non sequitur.  Netflix isn't advertising "authentication" of the stream.

[Samuel T Cogley]

4 minutes ago, The Computer Audiophile said:

Tell me a practical, non-lab, scenario where this could occur. 

 

Doesn't matter.  The authentication has been broken.

 

EDIT: If you alter the file, and the blue light still comes on, the "authentication" is bogus.

[Samuel T Cogley]

6 minutes ago, The Computer Audiophile said:

You better call Dolby as well because the same thing can be done for DTS etc...

 

Don't recall Dolby heralding their "authentication" scheme.  Detecting encoded material (even if it's intentionally adulterated) is a far different thing than advertising your "secure authentication" as a guarantee of "what the artist intended", only to demonstrate that the "authentication" light will still illuminate when the file has been altered.  Apples and oranges.

[Samuel T Cogley]

Just now, The Computer Audiophile said:

I think attacking MQA based on the fact that someone in a lab can change the file and make the blue light shine even though the file has been altered is rather dumb. 

 

I guarantee that you're browsing this site via SSL and your communication is encrypted if you see the pad lock in your browser. All people saying SSL is secure and people who show the padlock should immediately cease saying this is secure because this can be defeated in a laboratory. 

 

Makes no sense to me. 

 

Assuming you're not revealing an SSL vulnerability with your site(s), change just one bit of the data in the encrypted stream, and the alteration detection mechanisms will do their job and you'll know something's amiss.  And by the way, editing binary data in a file does not require a "laboratory" or even a white coat.  🙂

 

And I'm not "attacking" MQA.  I'm simply stating that the "authentication" has been effectively circumvented.  This is a fact.

[Samuel T Cogley]

5 minutes ago, The Computer Audiophile said:

You must have missed Edward Snowden's data dump. The capability is there. 

 

Those vulnerabilities are a few years old and have been addressed.  There's no doubt that SSL has its problems (not the least of which is the unknowns around possible backdoors in AES), but you can't compare it with the utterly broken "authentication" of MQA.  They're completely unrelated.

[Samuel T Cogley]

2 minutes ago, mansr said:

You guys are talking at cross purposes. Look at what Jim Austin wrote again (emphasis mine):

"After I'd finished with my listening, dCS alerted me to a possible error in my methodology: Grouped zones in Roon may not be bit-perfect. If the two DACs aren't both receiving the same, unaltered data, the test is invalid. But in my case, the data apparently were bit-perfect: When I played an MQA file through each of two grouped zones to both MQA-enabled DACs, both indicated that they were decoding MQA"

 

This isn't about authentication or possible ways of faking it. It's simply a quick test to see if Roon is messing with the data. Since the DACs still detect the streams as MQA, the top 16 bits have not been touched. Yes, if Roon had zapped the low 8 bits without using dither, the DACs would still indicated MQA. Is there any reason to believe Roon would be doing this or something even more convoluted in order to trick an MQA DAC into turning on the blue light? I don't think so. It is therefore a reasonable, if not bomb proof, test of bit-perfect transport.

 

The strength of the authentication isn't relevant here since, presumably, nobody is actively trying to trick it.

 

I was talking just about that the authentication does not detect certain kinds of of tampering.  I don't think there's any dispute about that.

[Samuel T Cogley]

21 minutes ago, Ishmael Slapowitz said:

It really bogged the mind why Stereophile, and dCS, for that matter, would waste so much time on MQA when it is available from one source, Tidal, and it has been soundly rejected by Qobuz and Amazon HD.

 

Can we really characterize high-end HiFi as a growth sector?  I'm thinking that luxury manufacturers like dCS need to check the "we decode everything" box just to maintain sales.  I've listened to a Vivaldi DAC (playing PCM) and liked it.  No way it was worth the outlay, but it was pleasant to listen to.

 

The Old Guard audiophile publications must at least appear to cater to the luxury sector.  So their interest in MQA is logical.  Is it pro-consumer? No way!

[Samuel T Cogley]

22 hours ago, Tintinabulum said:

Content on this thread doesn’t improve. Keep it going though.... by any means possible. 

 

I might be mistaken, but I'm pretty sure your subjective estimation of the quality of content in this thread is utterly irrelevant.

 

 

[Samuel T Cogley]

55 minutes ago, Tintinabulum said:

 

It obviously does. I think "hanging out" isn't a good description, I just "pop in" to see if there is anything new and what sort of stuff the gang are going on about to keep the topic interesting.

 

"All things Bob Stuart" is another poor term, I suppose it's meant to be a sort of insult. Meridian make some good gear, you'll never know about it, you simply dislike by association. Nobody is interested in me anyway, I'm not interesting.

 

I'm not really bothered about MQA. Other motivations exist in life...

 

Deflection and dissembling.

[Samuel T Cogley]

I just went and looked at the last 20 posts in that Roon thread.  The first comment I'll make is that Danny, in my experience as a Roon user and occasional contributor to that forum, never admits he's wrong about anything.  He always digs in and doubles down.  That's just who he is.

 

My other comment is that I thought @The Computer Audiophile did a great service to this community by framing the MQA debate from the perspective of someone who loves recorded music.

 

You'll never convince those people (I used to be one back in the HDCD days) who just want a light to illuminate.  Those people will always want the "latest and greatest" and they are, as @crenca might say, the primary "marks" of the Audiophile Confidence Game.

 

I admit I use Roon for one thing: getting the Qobuz stream to my DAC with as little adulteration as possible.  The product and its user base have evolved into a bit of a cult IMHO.  I'm also an Audirvana+ user and perhaps it's time to cut Roon loose.  I probably don't even need it anymore.

 

 

 

 

[Samuel T Cogley]

Roon radio drives me nuts and there's no way to disable it globally.  It always does a horrible job at guessing what I want to hear after my playlist ends.  Some people love it.  ¯\_(ツ)_/¯

[Samuel T Cogley]

12 minutes ago, firedog said:

 

Roon Radio also bugs me, so I limit it to my library only. And you can turn it off, in the "queue" sidebar. 

 

Agreed, but it's per "zone", unless they've changed that.  I have several "zones", so it's always been a pain.

[Samuel T Cogley]

52 minutes ago, KeenObserver said:

Jay-Z has returned his music to Spotify.  Tidal must not have been doing it for him.

 

Wow, I guess the bloom is off the Tidal rose.  Who could forget the pageantry of this event?

 

 

More details here on that event in case anyone forgot.

[Samuel T Cogley]

I can't help noticing that @ARQuint seems to be in this thread a lot more since Lee Scoggins became his new boss.  I'm sure it's a pure coincidence.  🙂

[Samuel T Cogley]

4 hours ago, Ralf11 said:

"By all appearances, the MQA revolution is poised to ruin the music industry just as the latest Star Wars blockbuster is ruining movies"

 

The "starwarsification" of Hollywood is an actual thing.

[Samuel T Cogley]

3 hours ago, christopher3393 said:

Those of you that have been strongly anti-MQA ( which ,depending on what form, makes good sense!), do you have any regrets regarding any posts you made, some of which, while literally may have been "on topic" may have derailed more genuine conversation? I'll readily say that, imo, Lee Scoggins acquitted himself very poorly here and elsewhere for reasons that were laid out best by firedog and tmtomh among others. And there were at least a couple of others that struck me as zealots of a hobby fanatic or die-hard advert type.

 

Regarding Scoggins, I believe that disingenuousness is just as rude as "go f your mother".  So regrets?  No.  I appreciate that some might think that disingenuousness is more intellectually refined than "go f your mother" and somehow deserves more respect.  So we'll just have to agree to disagree on this.

[Samuel T Cogley]

6 hours ago, ARQuint said:

 

Even at this late date, I'm not certain what to make of Rt66indierock—he is such a puzzling mash-up of contradictory impulses. His style of expressing himself is elliptical and sometimes demonstrates less than a complete mastery of the English language. As Chris has pointed out, he can be awfully grandiose and, even though he's hanging with a crowd that angrily calls for deep-sixing the Old Guard, he never misses a chance to name an "industry insider" he's chatted up for ten minutes at an audio show.

 

If only you could have devoted this much time and effort to actually join in the discussion about MQA.  Your talent for ad hominem is impressive.  Your subtle suggestion that English may not be @Rt66indierock 's first language is particularly skillful.

 

But please let's keep focus on MQA and not let the content of this thread be dictated by the Old Guard.

[Samuel T Cogley]

40 minutes ago, fas42 said:

 

Probably, because the people with the expertise to do uncrushing aren't business people! I've done a number of experiments over the years that demonstrates, to me, that expanding poor dynamic range is not that hard - and could be turned into a largely automatic process, with some time time and effort put into it - what's hard is revving up the whole business machinery apparatus, to make it worthwhile for the individuals to go through the steps of making it happen.

 

John's work on changing the structure of tracks is an example of what can be done - and I consider the complexity of what his processing does as being significantly greater than that needed for dynamic range expansion ...

 

While you can use DSP to add dynamic range to previously compressed recordings, I hope you're not suggesting that the output of that process bears a significant resemblance to what the recording was before being compressed.  At best, it will be a facsimile of an uncompressed version.

 

Comparing material that was previously encoded in Dolby A is a little bit misleading, because there is dynamic range compression as part of the encoding process and the restoration of the original dynamic range was/is possible because of the encoding.

 

[Samuel T Cogley]

20 hours ago, Ishmael Slapowitz said:

More utter nonsense from Stereophile's 75 year old fossils.

 

Fossils can't type.  They're geezers. 🙂

[Samuel T Cogley]

On 4/2/2021 at 7:34 PM, ARQuint said:

 

Cookie Marenco is a respected engineer and producer with 5 Grammy nominations. She has recorded Brad Mehldau, Ladysmith Black Mambazo, and Mary Chapin Carpenter and uses her real name. It's highly doubtful that "Ishmael Slapowitz" has any qualifications as an audio professional and has exactly one criterion for who is worthy in the field and who isn't. Most, me included, recognize that Slapowitz gets his jollies by riling people up and is here for his entertainment value. But I also feel it doesn't reflect well on AS for an especially conscientious and generous member of our industry like Marenco to be subject to preadolescent name-calling.

 

It also doesn't help the case of more thoughtful critics of MQA.

 

Andy Quint

 

 

 

Any recording professional that puts forth the notion that "DRM sounds great" should be ashamed.  You would be ashamed of your MQA support as well.

[Samuel T Cogley]

4 hours ago, JoshM said:

Not sure whether this is better placed in this thread, the thread on @GoldenOne’s video, or the ASR thread, but:

 

1) Over at ASR, John Atkinson is claiming that Golden’s test is invalid since everyone knows a lossy encoder (we’re now apparently conceding that MQA is lossy) can’t handle the signals Golden encoded. This is the same claim Amir made, and if you look at John’s “likes” at ASR, he’s “liking” every post criticizing Golden’s test and defending MQA. 
 

2) Amir has just given a response that completely negates the point of every measurement he’s ever done:

 

 

 

 

Ok, so let me see if I'm following this logic:

 

• Amir literally makes a name for himself by...... using test signals to test DAC performance.  Not music, TEST SIGNALS
• But test signals are suddenly not suitable to evaluate the performance of an audio CODEC

 

I call shenanigans!!!  We know a lot about the performance of CODECs such as MP3 and AAC because..... TEST SIGNALS!!!

 

 

[Samuel T Cogley]

Since we're talking about Roon, I just wanted to pass along something that I discovered in the IT security realm.  Roon uploads a file to the Roon mothership called "kartpostable.tgz", which Danny at Roon describes as:

 

Quote

The most important thing is that it contains the publisher IDs for the lyrics you download and information about how often you view those lyrics. We pay licensing costs based on that information. It contains some other information as well, like the capabilities of your OpenGL driver and library statistics.

 

It's important to note that I'm not suggesting anything is untoward in Roon uploading this file behind the scenes.  But I am suggesting that preventing this file from being uploaded could allow you to decode MQA without Roon knowing about it, therefore not generating additional revenue for MQA.

 

 

[Samuel T Cogley]

4 hours ago, The Computer Audiophile said:

Does anyone know the relation of Roon's Sarah Stuart to MQA's Bob Stuart?

 

"Sarah works on music editorial and research as part of Roon’s Music Team." https://blog.roonlabs.com/author/sarah/

 

https://uk.linkedin.com/in/sarah-stuart-7889b1150

 

 

She shares a last name with Mr. Stuart.  I'm a little surprised you seem to almost be asking the forum for help doxing someone.  Bad form for the forum owner, and potentially more ammo for MQA to throw hate at this forum.  I'm perplexed, to say the least.