Brinkman Ship Posted August 14, 2018 Share Posted August 14, 2018 Zen & the Art of A/D Conversion: "In a series of recent feature articles for Stereophile, Jim Austin has examined how the controversial MQA codec works: "MQA Tested, Part 1," "MQA Tested Part 2: Into the Fold," "MQA Contextualized," "MQA, DRM, and Other Four-Letter Words," and, most recently, "MQA: Aliasing, B-Splines, Centers of Gravity." I doubt there is a Stereophile reader who is unaware of the fracas associated with MQA, and I have been repeatedly criticized on web forums for describing its underlying concept as "elegant." But elegant it is, I feel. MQA Ltd.'s Bob Stuart has described the goal of MQA as being to reduce to "plumbing" everything between the original analog signal fed to the analog/digital (A/D) converter and the analog signal output by the digital/analog (D/A) converter, other than routing the signal from the original event to the end-user's system. In other words, the A/D conversion of the output of the microphone preamps (in a purist recording) or the mixing console (in a conventional recording), the transmission, storage, and subsequent D/A conversion will be transparent, except for an ultrasonic rolloff equivalent to a signal path of a few feet in air." https://www.stereophile.com/content/zen-art-ad-conversion#bf4kky2Hi5SiOKXP.99 Link to comment
Popular Post Indydan Posted August 14, 2018 Popular Post Share Posted August 14, 2018 Oh FFS! Stereophile just can't leave it alone. They are still plugging MQA. Thuaveta, lucretius, tmtomh and 2 others 4 1 Link to comment
Popular Post kumakuma Posted August 14, 2018 Popular Post Share Posted August 14, 2018 26 minutes ago, Indydan said: Oh FFS! Stereophile just can't leave it alone. They are still plugging MQA. https://www.logicallyfallacious.com/tools/lp/Bo/LogicalFallacies/173/Sunk_Cost_Fallacy http://changingminds.org/principles/consistency.htm MikeyFresh, esldude, lucretius and 2 others 4 1 Sometimes it's like someone took a knife, baby Edgy and dull and cut a six inch valley Through the middle of my skull Link to comment
Popular Post crenca Posted August 14, 2018 Popular Post Share Posted August 14, 2018 1 hour ago, Brinkman Ship said: But elegant it is, I feel. MQA Ltd.'s Bob Stuart has described the goal of MQA as being to reduce to "plumbing" everything between the original analog signal fed to the analog/digital (A/D) converter and the analog signal output by the digital/analog (D/A) converter, other than routing the signal from the original event to the end-user's system. Is John Atkinson the Bill Clinton of Audiophiledom? ? He (and all the rest of the MQA shill trade publications) have a problem with the distance between what MQA claims and what it actually IS. From the secret sauce A/D correction at the beginning, through to the supposed authentication, the bandwidth savings, all the way to the consumers DAC and digital ecosystem MQA is an empty promise. It does not actually do any of the things for which it would be "elegant". The only thing that it actually does is provide Meridian/MQA/Bob Stuart with a closed proprietary rent seeking system, and a bit of DRM for the labels. If a consumer really does like the sound of MQA's leaky min phase DAC filtering scheme, they can easily (and for free!) reproduce it themselves. It is anything but "elegant" to force the entire music reproduction and delivery chain into this controversial definition of "original signal". Why trade publication editors continue to shill MQA is conjecture, but the fact that they are not actually interested in what is good for the Audiophile consumer (their customers are their advertisers, not their readers) obviously plays a large part. Of course everyone around here already knows this, but I thought a summary might be helpful to any new readers. adamdea, MikeyFresh, Hugo9000 and 4 others 4 3 Hey MQA, if it is not all $voodoo$, show us the math! Link to comment
Popular Post Brinkman Ship Posted August 14, 2018 Author Popular Post Share Posted August 14, 2018 Um. do you mean to say that despite the fact it is lossy, proprietary, includes aliasing and distortion, and is NOT a true representative of the master, and an empty fee generator..it is WAY COOL elegant?? ? esldude, MikeyFresh and MrMoM 2 1 Link to comment
Popular Post mansr Posted August 14, 2018 Popular Post Share Posted August 14, 2018 44 minutes ago, crenca said: Is John Atkinson the Bill Clinton of Audiophiledom? That depends upon what the meaning of the word is is. Avenging Fool, lucretius and Nordkapp 1 1 1 Link to comment
Popular Post mansr Posted August 14, 2018 Popular Post Share Posted August 14, 2018 1 hour ago, kumakuma said: https://www.logicallyfallacious.com/tools/lp/Bo/LogicalFallacies/173/Sunk_Cost_Fallacy http://changingminds.org/principles/consistency.htm Argumentum ad nauseam. Nordkapp, kumakuma and Indydan 1 2 Link to comment
Popular Post mrvco Posted August 15, 2018 Popular Post Share Posted August 15, 2018 Elegant in a Divine sort of way. lucretius, Thuaveta, miguelito and 1 other 2 1 1 -- My Audio System Link to comment
DarwinOSX Posted August 15, 2018 Share Posted August 15, 2018 MQA rocks. Loving it on Tidal. Link to comment
Brinkman Ship Posted August 15, 2018 Author Share Posted August 15, 2018 15 minutes ago, DarwinOSX said: MQA rocks. Loving it on Tidal. miguelito 1 Link to comment
Popular Post esldude Posted August 15, 2018 Popular Post Share Posted August 15, 2018 You want to know about elegance. How about this? Have an ADC which can convert an analog input to digital with 20 bit accuracy, flat response, and distortion so low as to be negligible and completely inaudible in any way shape or form. Send digital signal to a DAC that can convert input to analog with 20 bit accuracy, flat response, and distortion so low as to be negligible and completely inaudible in any way shape or form. This second part elegantly being a direct mirror image of the first conversion. Elegantly making the conversion disappear from the signal when all is said and done. Why it is as if the original signal has passed thru a very short wire directly unadulterated to you across space and time. Just simple plumbing of the signal for real. Robert Stuart even wrote a paper investigating and decided such a system is fully blameless at either 18 or 19 bit accuracy levels. Less with good dither. Such a system is of course well done PCM. It is simple, and unencumbered by gate keeper corporations. We already have the real elegance. MQA is like the ugly vile disgusting evil toad that looks into a mirror and sees some illusion of beauty and elegance. Everyone else without the magic mirror looks and sees an ugly vile disgusting evil toad that is either delusional or trying to put one over on us. In this case I think it is both. So where are the journalists getting their magic mirrors? I think they must have a small one in their wallets. lucretius, bachish, Nikhil and 1 other 2 2 And always keep in mind: Cognitive biases, like seeing optical illusions are a sign of a normally functioning brain. We all have them, it’s nothing to be ashamed about, but it is something that affects our objective evaluation of reality. Link to comment
NOMBEDES Posted August 15, 2018 Share Posted August 15, 2018 A new audio term: Ugly, Vile, Disgusting, Toad. (UVDT) So: MQA = UVDT Got it, thanks! In any dispute the intensity of feeling is inversely proportional to the value of the issues at stake ~ Sayre's Law Link to comment
Popular Post firedog Posted August 15, 2018 Popular Post Share Posted August 15, 2018 So I skimmed through JA's new article. The point was that MQA and Ayre get to a similar result with different methodology? Both managed to reproduce the signal with almost no ringing? I'm not sure how this makes points for MQA, which is what JA seems to be trying to do. If I understood the article correctly, Ayre managed to create basically a perfect ADC/DAC conversion with low distortion and virtually no ringing. Even if MQA did the same, isn't that more proof of how unnecessary MQA is? Isn't that proof it isn't needed for "de-blurring"? crenca, Avenging Fool, Dr Tone and 4 others 3 4 Main listening (small home office): Main setup: Surge protector +>Isol-8 Mini sub Axis Power Strip/Isolation>QuietPC Low Noise Server>Roon (Audiolense DRC)>Stack Audio Link II>Kii Control>Kii Three (on their own electric circuit) >GIK Room Treatments. Secondary Path: Server with Audiolense RC>RPi4 or analog>Cayin iDAC6 MKII (tube mode) (XLR)>Kii Three . Bedroom: SBTouch to Cambridge Soundworks Desktop Setup. Living Room/Kitchen: Ropieee (RPi3b+ with touchscreen) + Schiit Modi3E to a pair of Morel Hogtalare. All absolute statements about audio are false Link to comment
mansr Posted August 15, 2018 Share Posted August 15, 2018 7 hours ago, NOMBEDES said: A new audio term: Ugly, Vile, Disgusting, Toad. (UVDT) Maybe if you kiss it, it'll turn into a prince. Link to comment
miguelito Posted August 15, 2018 Share Posted August 15, 2018 10 hours ago, Brinkman Ship said: Oh please, not the dotard here as well!!! NUC10i7 + Roon ROCK > dCS Rossini APEX DAC + dCS Rossini Master Clock SME 20/3 + SME V + Dynavector XV-1s or ANUK IO Gold > vdH The Grail or Kondo KSL-SFz + ANK L3 Phono Audio Note Kondo Ongaku > Avantgarde Duo Mezzo Signal cables: Kondo Silver, Crystal Cable phono Power cables: Kondo, Shunyata, van den Hul system pics Link to comment
Popular Post pkane2001 Posted August 15, 2018 Popular Post Share Posted August 15, 2018 7 hours ago, esldude said: So where are the journalists getting their magic mirrors? I think they must have a small one in their wallets. They are desperately trying to hold on to the belief in magic. They don't want anyone telling them that Santa isn't real. And this applies to more than journalists. Shadders, Ralf11 and lucretius 3 -Paul DeltaWave, DISTORT, Earful, PKHarmonic, new: Multitone Analyzer Link to comment
Popular Post miguelito Posted August 15, 2018 Popular Post Share Posted August 15, 2018 "Elegance"? Really? WTF? Let me list the lack of "elegance" MQA entails: 1- Throw information away when you don't need to at the encoding stage 2- Attach all sorts of untrue claims to your product 3- Design that makes DAC implementations extremely hard and limiting 4- Requirements for licenses If at least Bob Stuart dressed well from all this money - but he looks like a bum. Like Coco Chanel once said: "Dress up, then take one piece off." Lets take MQA off. crenca, MikeyFresh, Hugo9000 and 1 other 1 3 NUC10i7 + Roon ROCK > dCS Rossini APEX DAC + dCS Rossini Master Clock SME 20/3 + SME V + Dynavector XV-1s or ANUK IO Gold > vdH The Grail or Kondo KSL-SFz + ANK L3 Phono Audio Note Kondo Ongaku > Avantgarde Duo Mezzo Signal cables: Kondo Silver, Crystal Cable phono Power cables: Kondo, Shunyata, van den Hul system pics Link to comment
psjug Posted August 15, 2018 Share Posted August 15, 2018 7 hours ago, NOMBEDES said: A new audio term: Ugly, Vile, Disgusting, Toad. (UVDT) So: MQA = UVDT Got it, thanks! SQAM MQA denotes the lossy process with phase anomalies Link to comment
james45974 Posted August 15, 2018 Share Posted August 15, 2018 There seems to be some cadence to these articles on MQA. Just when things have quieted down and gone silent all of a sudden a brand new article appears. They almost seem desperate to keep MQA in the public conscience. MikeyFresh 1 Jim Link to comment
Jud Posted August 15, 2018 Share Posted August 15, 2018 1 hour ago, firedog said: So I skimmed through JA's new article. The point was that MQA and Ayre get to a similar result with different methodology? Both managed to reproduce the signal with almost no ringing? I'm not sure how this makes points for MQA, which is what JA seems to be trying to do. If I understood the article correctly, Ayre managed to create basically a perfect ADC/DAC conversion with low distortion and virtually no ringing. Even if MQA did the same, isn't that more proof of how unnecessary MQA is? Isn't that proof it isn't needed for "de-blurring"? Well, "perfect," who knows? Nicely done and preferred by many, sure. The reason the Ayre filter doesn't ring is because it isn't very steep, so it may let through some frequencies that create aliasing, imaging, and higher THD numbers. (Not sure I'm remembering correctly, but Ayre DACs may at least at one time have had different "Listen" and "Measure" filters.) Similar thing applies to MQA - doesn't ring because the filters aren't steep, which allows for aliasing, imaging, and increased THD. One never knows, do one? - Fats Waller The fairest thing we can experience is the mysterious. It is the fundamental emotion which stands at the cradle of true art and true science. - Einstein Computer, Audirvana -> optical Ethernet to Fitlet3 -> Fibbr Alpha Optical USB -> iFi NEO iDSD DAC -> Apollon Audio 1ET400A Mini (Purifi based) -> Vandersteen 3A Signature. Link to comment
mav52 Posted August 15, 2018 Share Posted August 15, 2018 If Charles Hansen was still with us, I would bet he would have a counter argument to JA's article. Indydan 1 The Truth Is Out There Link to comment
Popular Post FredericV Posted August 15, 2018 Popular Post Share Posted August 15, 2018 16 hours ago, Brinkman Ship said: "MQA: Aliasing, B-Splines, Centers of Gravity." I doubt there is a Stereophile reader who is unaware of the fracas associated with MQA, and I have been repeatedly criticized on web forums for describing its underlying concept as "elegant." I can clearly hear the difference between standard minimum phase upsampling, and minimum phase upsampling where the post-ringing is reduced to one cycle + aliasing. So this test is very stupid: Quote Stuart: In all cases the aliasing heard by a listener with an MQA decoder will be well below that implied in the quoted patent claim and will be, we claim, either inaudible or nonexistent. [To test this claim, beginning with a FLAC file containing white noise at –10dBFS peak, I pasted in 20 seconds from Talking Heads' "Girlfriend Is Better" at the 20s mark, 50dB below the noise, repeating the music and increasing the level by 10dB every 20 seconds. I can detect very faint drums at the one-minute mark, 30dB below the noise level and at least 30dB louder than the aliased-content level allowed by the MQA specification. By 20dB below the noise—40dB above the spec—I could hear the music clearly. My conclusion: The specified level of aliasing is not audible, with a safe safety margin. The use of white noise instead of a 1/f, music-like signal makes this a very conservative test. The reason why is very simple: MQA's aliasing is correlated to the music signal, while in the above simulation, we compare uncorrelated noise with an attenuated music signal. There are even youtube video's where you can see this correlated aliasing in action. Hans Beekhuyzen is another MQA influencer who use the same simplified "fake" tests where he fails to disclose how he created his listening samples, like in the time smear video. When someone then asks the more technical questions, he answers his channel is not scientific but for lay persons. crenca, MikeyFresh and lucretius 1 2 Designer of the 432 EVO music server and Linux specialist Discoverer of the independent open source sox based mqa playback method with optional one cycle postringing. Link to comment
Jud Posted August 15, 2018 Share Posted August 15, 2018 25 minutes ago, mav52 said: If Charles Hansen was still with us, I would bet he would have a counter argument to JA's article. If his take on DSD was any indication (he seemed to me to still be pretty pissed at Sony's poor attempt to take over the market with copy-protected SACDs, and thus had no time for anything related to SACD, including DSD), I can just imagine. mav52 1 One never knows, do one? - Fats Waller The fairest thing we can experience is the mysterious. It is the fundamental emotion which stands at the cradle of true art and true science. - Einstein Computer, Audirvana -> optical Ethernet to Fitlet3 -> Fibbr Alpha Optical USB -> iFi NEO iDSD DAC -> Apollon Audio 1ET400A Mini (Purifi based) -> Vandersteen 3A Signature. Link to comment
Brinkman Ship Posted August 15, 2018 Author Share Posted August 15, 2018 34 minutes ago, Jud said: If his take on DSD was any indication (he seemed to me to still be pretty pissed at Sony's poor attempt to take over the market with copy-protected SACDs, and thus had no time for anything related to SACD, including DSD), I can just imagine. Not entirely true... Hansen became much more neutral about DSD as a recording medium..yes he was not happy about DRM'd SACDs, but began to realize the appeal of DSD..very analog, slightly softer transients...altthough he still preferred 24/192 PCM himself. IN FACT, he published his own DSD/PCM comparison with the Ayre ADC- Unfortunately, the link no longer works, but here is a link from this forum. You find it interesting that if I remember correctly, it was basically a 50/50 split on preference. I personally preferred the DSD files. MikeyFresh 1 Link to comment
Popular Post mcgillroy Posted August 15, 2018 Popular Post Share Posted August 15, 2018 Boy oh boy, @John_Atkinson outdid himself with this one. I am not sure what I find more insidious: a.) his ignorance of all the proven shortcomings of MQA - reduced bitdepth, leaky filters, DRM - in order to safe his "elegant" claim. Which he solely rests on the ringing-phenomenon - where MQA adds nothing new beyond existing approaches. or b.) robbing a dead man of his dignity making him all but ventriloquising arguments in favour of MQA. A dead man who critiqued MQA up to his very last moment.On top of it Stuart is given a whole page for his claims - leaving us to imagine what Hansen would have answered. MQA-journalism knows no limits. Even worse it leaves no depth unprobed. I might be overreacting but I am truly appalled. MikeyFresh, lucretius, NOMBEDES and 2 others 4 1 Link to comment
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