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Post by novisnick on Feb 17, 2017 12:29:13 GMT -5
I'll continue with this state of the art system! Only my approval required.
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Post by Loop 7 on Feb 17, 2017 12:42:02 GMT -5
I'll continue with this state of the art system! Only my approval required. Hmmm... Maybe someone will conceive a special LP mastering scheme that would require vinyl pressing plants and turntable manufacturers to license their products.
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Post by monkumonku on Feb 17, 2017 12:46:30 GMT -5
Seems to me that MQA is kind of like the Affordable Health Care Act.
No one really understands it but they're just supposed to sign on the dotted line anyway.
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Post by Casey Leedom on Feb 17, 2017 13:52:06 GMT -5
Thank you KeithL for your many fine detailed posts on this. So let me see if I can decompose this pedagogically: Basic Analog to Digital and Digital to Analog: - The Analog to Digital process introduces errors. Effectively it's a Lossy Transcription and has to be.
- But those errors can be characterized and attempts can be made to "reverse" them in the Digital to Analog process. (And, in fact, many DACs have a variety of filters for various reconstruction profiles.) But, there's no way around the fact that this is another Lossy Transcription.
It appears that MQA is claiming that they have a way of handling the Analog to Digital -> Digital to Analog Conversion process which results in a better Aggregate Analog Error than current techniques. This seems to center around the idea of understanding the error created by the two Lossy Transcriptions, and also knowing what Digital Data can be thrown away without affecting the error in a significant fashion (as far as human perception is concerned). Now, if the above were true, I'd want to see the scientific papers which backed up those claims. Casey
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Post by goodfellas27 on Feb 17, 2017 14:05:53 GMT -5
I am not sure where people are getting to hardware design "approval" process from. Last time I checked they submit their DAC specification and MQA would provide a custom firmware code for that DAC "profile". The specification is to make sure there's enough compute power to decode MQA and bypass that DAC "secret" sauce. MQA is an Analog-to-Analog process. I guess Pioneer, Mytek, Onkyo, Bluesound, Meridian, Cary Audio, Brinkmann, NAD, Technics, Audioquest and others love getting their design approved www.stereophile.com/content/mqa-questions-and-answers#YD5X4IwHUE8Fd4hT.97The reason many hardware DAC manufacturers aren't buying into this is quite simple. MQA wants to have "approval" on every DAC design that carries the logo - which means that you have to get every design approved by them before you can sell it. (In other words they're asking every manufacturer to subject his products to "outside approval" by them.) This would only be even vaguely reasonable if there was a huge amount of customer interest (read that as +$$$) involved. Imagine what would happen if Exxon demanded approval on every new car design...... I assume Dolby and DTS do not require approval before a manufacturer can sell an AVR or pre/pro? If not, this is a MAJOR difference.
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KeithL
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Post by KeithL on Feb 17, 2017 14:13:27 GMT -5
That's EXACTLY the way I read it. And what we currently seem to have is that a lot of people claim that at least some of the MQA processed content sounds subjectively better. But what we're entirely missing is any actual study comparing the analog originals to the final output (since it's analog we can't just do a bit-compare). None of the people who like MQA so far have had any opportunity to actually compare it to the analog originals..... (So all we have so far is that we have different re-mastered copies that sometimes better and happen to have been MQA processed.) The other thing that everyone seems to gloss over is the provenance of the content they're comparing. Are they comparing a CD to the exact same content from that CD processed through MQA..... Or are they comparing the CD version to an MQA version created from a different 24/96k original? If the latter, then how can we know how much of the difference to credit to the re-mastering itself? and how much to the fact that it's 24/96k? and how much to the MQA processing? (After all, I've heard plenty of 24/96k remasters that weren't MQA processed but still sounded a lot better than the CD.) I'll be waiting to compare 24/96k MQA versions to 24/96k PCM versions of the same master. (And I have to interject, just to rain on the parade of analog fans everywhere...... that every step in the analog reproduction chain is also lossy - just in different ways.) Thank you KeithL for your many fine detailed posts on this. So let me see if I can decompose this pedagogically: Basic Analog to Digital and Digital to Analog: - The Analog to Digital process introduces errors. Effectively it's a Lossy Transcription and has to be.
- But those errors can be characterized and attempts can be made to "reverse" them in the Digital to Analog process. (And, in fact, many DACs have a variety of filters for various reconstruction profiles.) But, there's no way around the fact that this is another Lossy Transcription.
It appears that MQA is claiming that they have a way of handling the Analog to Digital -> Digital to Analog Conversion process which results in a better Aggregate Analog Error than current techniques. This seems to center around the idea of understanding the error created by the two Lossy Transcriptions, and also knowing what Digital Data can be thrown away without affecting the error in a significant fashion (as far as human perception is concerned). Now, if the above were true, I'd want to see the scientific papers which backed up those claims. Casey
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KeithL
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Post by KeithL on Feb 17, 2017 14:32:44 GMT -5
Yes.... but the uncertainty lies in how much each step matters... and what you'll miss by skipping one or the other. The initial "correction" or "improvement" occurs at the ENCODING step. And they claim you will hear an improvement even if no further decoding is done and you play it back on ordinary equipment. The first decoding step "decodes" or "better reproduces" more of that difference. (This can be software or hardware.) The second decoding step must be done in hardware - because it is customized/optimized for the specific hardware involved. This is the part that's unclear. For example, claiming that the content is "unfolded to 192k" is somewhat specious when the output is ANALOG. (I interpret this to be a claim that the oversampling and filtering normally found in all DACs is somehow optimized in MQA DACs to work better with MQA content.) The overall claim is that, in order to get the best performance, every device and every step of the process itself must be "MQA certified" (and you pay for each one). They keep rearranging and restating the details - but that overall assertion seems rock solid The current reorganization seems to be moving in the direction of allowing you to buy parts of the whole enchilada..... so, for example, instead of paying a lot for an MQA DAC, you can buy an MQA software player and an MQA renderer..... The logical assumption would be that they will be able to demonstrate an audible improvement at each step, to convince you to come back and buy the next step. Of course, the sinister aspect of it would come about when someone tells you that, in order to really get a benefit from that MQA content you already bought, you're going to have to buy just... one... more... little box. There's also another unstated bit of confusion..... MQA can only be an analog-to-analog process if you're starting with an analog master. In that situation you can actually do an end-to-end MQA process. However, with current existing masters that are digital, you're substituting "repair existing damage as well as we can" for "starting with the original". (In that situation there is no analog original... and I'm not aware of any "full MQA mastered originals" yet... although there may be some out there. ) This is all a tactful way of saying that you can't listen to "a full MQA production" yet because there aren't any yet..... (I would also point out that analog tape masters are themselves quite flawed..... which would be one of the things this whole process is supposed to help eliminate.) SO MUCH FOR MQA DACS......
According to the latest press releases, the next version of Audirvana (the popular music player for Apple computers) will do FULL MQA DECODING IN SOFTWARE. I would expect to see similar support to appear in other major players sometime soon.
This is confusing! Do you need or not an MQA dac to get the "full effect"?
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Post by KeithL on Feb 17, 2017 14:57:21 GMT -5
You seem to have found different wording that what I saw. The way I saw it described was that they had to validate your design, approve it in terms of meeting certain of their requirements for temporal accuracy, and "correct your design for you if necessary". Then, after agreeing that you have a DAC which meets their requirements, they must then measure it (which is how they create their profile of it). Then, having that profile in hand, they will develop and customize the firmware for your specific product. And, of course, if you ever want to change the design of your DAC at all, you'll have to go through the whole approval and profiling process again. (This was from one of their earlier press releases or interviews.) Now, of course, I wouldn't be surprised if they're willing to forego certain otherwise "necessary" steps - for enough money. Note that I'm getting this information from their public statements of what would be involved. (I haven't seen the actual contract, which may have turned out to be nothing like what they said it was at all.) Incidentally - regardless of whether MQA is "an analog to analog process" in the overall sense. From the point of view of the DAC it is simply a "decode according to the specs" process. And to answer Loop 7.... Dolby Labs and DTS do both require you to buy a license, then to have your products that use their technologies tested and validated by them. (Although they may allow some large customers to "self validate" under some circumstances... which is not unusual in the industry.) But, then, to be blunt, Dolby and DTS bring a few tens of millions of customers to the table to justify the aggravation. Now, I'll ask you an interesting question...... If MQA approval will ensure a specific and very high level of performance.... And both the $99 Dragonfly and the $2k Mytek Brooklyn have been properly profiled, optimized, and corrected.... Then are we saying that, since they both are MQA approved, they both sound the same? Or are we saying that MQA approval DOESN'T mean they'll sound the same after all? (If so, then it makes one wonder why anyone would spend more than $100 on a DAC). Note that such an idea would especially depress big box manufacturers like Marantz.... (However, you may be shocked to know that some DAC designers, who charge a lot of money for their "secret sauce", don't WANT it bypassed - or replaced by MQA's secret sauce.) But it does make you wonder why Mytek would want their nice $2k DAC put in the same class as the little DF. Or are we really saying that all that MQA stuff is just one more technology to add some improvement to whatever performance your DAC already delivers? (It is rather confusing - isn't it?) I am not sure where people are getting to hardware design "approval" process from. Last time I checked they submit their DAC specification and MQA would provide a custom firmware code for that DAC "profile". The specification is to make sure there's enough compute power to decode MQA and bypass that DAC "secret" sauce. MQA is an Analog-to-Analog process. I guess Pioneer, Mytek, Onkyo, Bluesound, Meridian, Cary Audio, Brinkmann, NAD, Technics, Audioquest and others love getting their design approved www.stereophile.com/content/mqa-questions-and-answers#YD5X4IwHUE8Fd4hT.97I assume Dolby and DTS do not require approval before a manufacturer can sell an AVR or pre/pro? If not, this is a MAJOR difference.
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Post by Boomzilla on Feb 17, 2017 14:57:32 GMT -5
Mr. Levkof -
Correct me if I'm wrong, please:
To my understanding, if MQA knows the A-to-D device that was used to originally transcribe an analog master to digital, then (and only then) does the MQA remastering process compensate for the phase damage done by that original A/D conversion.
As a second part of the "MQA-remastering" process, the original digital conversion is upsampled to higher bit depth and sampling rate.
The third part of the "MQA-remastering" involves using a lossy CODEC to repackage the high treble of the MQA-remastered music for smaller file size.
At this point, the MQA file is a "Studio-Master" quality copy of the original analog file (per MQA).
Upon playback, however, the MQA-compatible DAC not only "unfolds" the MQA file, but also restores the high treble to its proper place in the file.
Additionally, IF (and only if) the MQA DAC knows the specific make, model, and filter implementation of its D to A converter, then the MQA program ALSO compensates for the distortion and high-frequency truncation expected from the playback A/D conversion.
At this point, what comes out of the DAC should, in theory (and according to MQA) be a virtually exact copy of the original analog recording that started the whole process, and in full "studio master" quality.
Per my understanding, all the above are MQA's claims.
Do I have it right so far, or have I mangled or missed anything?
Thanks - Boom
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Post by KeithL on Feb 17, 2017 15:11:53 GMT -5
Both Dolby and DTS require testing and licensing.... and it is a bit of a nuisance. HOWEVER, to put things into perspective there...... Support for Dolby and DTS surround sound are virtual requirements for a surround sound processor. (We wouldn't sell very many if they were missing one or the other.) In contrast, there are about a half dozen people here on the forum who seem especially worried about MQA. And I've talked to a total of a dozen or so on the phone (most of whom were curious or confused rather than worried about it). (And there are plenty of more people who are waiting to see if it catches on.) Major manufacturers are always on the lookout for one more logo to put on the front of their box. I'll bet that, if you look at the logos on a typical low-cost Pioneer AVR, you couldn't even tell me what half of them are. (I certainly don't know what a good few of them are for.) Even among smaller product makers extra features have value..... It will remain to be seem how much value being "the first sub $200 DAC to have MQA" has for the company who claims it. (And, now that everybody's joining the bandwagon, how much value being "one of the half that have it" carries.) As you probably know by now, Emotiva isn't big on jumping on bandwagons (unless they're well occupied). I assure you that, as soon as we get the idea that a significant number of our customers actually care about MQA, we'll seriously consider adding it. The reason many hardware DAC manufacturers aren't buying into this is quite simple. MQA wants to have "approval" on every DAC design that carries the logo - which means that you have to get every design approved by them before you can sell it. (In other words they're asking every manufacturer to subject his products to "outside approval" by them.) This would only be even vaguely reasonable if there was a huge amount of customer interest (read that as +$$$) involved. Imagine what would happen if Exxon demanded approval on every new car design...... I assume Dolby and DTS do not require approval before a manufacturer can sell an AVR or pre/pro? If not, this is a MAJOR difference.
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Post by Axis on Feb 17, 2017 15:26:06 GMT -5
Mr. Levkof - Correct me if I'm wrong, please: To my understanding, if MQA knows the A-to-D device that was used to originally transcribe an analog master to digital, then (and only then) does the MQA remastering process compensate for the phase damage done by that original A/D conversion. As a second part of the "MQA-remastering" process, the original digital conversion is upsampled to higher bit depth and sampling rate. The third part of the "MQA-remastering" involves using a lossy CODEC to repackage the high treble of the MQA-remastered music for smaller file size. At this point, the MQA file is a "Studio-Master" quality copy of the original analog file (per MQA). Upon playback, however, the MQA-compatible DAC not only "unfolds" the MQA file, but also restores the high treble to its proper place in the file. Additionally, IF (and only if) the MQA DAC knows the specific make, model, and filter implementation of its D to A converter, then the MQA program ALSO compensates for the distortion and high-frequency truncation expected from the playback A/D conversion. At this point, what comes out of the DAC should, in theory (and according to MQA) be a virtually exact copy of the original analog recording that started the whole process, and in full "studio master" quality. Per my understanding, all the above are MQA's claims. Do I have it right so far, or have I mangled or missed anything? Thanks - Boom I'm not Keith, but Boom get in there and find out. This is right up your alley Boom. I am not buying it. I am not re buying any music that has been folded like origami so it needs to be unfolded. You guys remember this thread when the price of music goes up because you buy into everything they sell you. Get a grip on what the original recording is. There is no going back and magic that can make it better.
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Post by pedrocols on Feb 17, 2017 15:28:57 GMT -5
Mr. Levkof - Correct me if I'm wrong, please: To my understanding, if MQA knows the A-to-D device that was used to originally transcribe an analog master to digital, then (and only then) does the MQA remastering process compensate for the phase damage done by that original A/D conversion. As a second part of the "MQA-remastering" process, the original digital conversion is upsampled to higher bit depth and sampling rate. The third part of the "MQA-remastering" involves using a lossy CODEC to repackage the high treble of the MQA-remastered music for smaller file size. At this point, the MQA file is a "Studio-Master" quality copy of the original analog file (per MQA). Upon playback, however, the MQA-compatible DAC not only "unfolds" the MQA file, but also restores the high treble to its proper place in the file. Additionally, IF (and only if) the MQA DAC knows the specific make, model, and filter implementation of its D to A converter, then the MQA program ALSO compensates for the distortion and high-frequency truncation expected from the playback A/D conversion. At this point, what comes out of the DAC should, in theory (and according to MQA) be a virtually exact copy of the original analog recording that started the whole process, and in full "studio master" quality. Per my understanding, all the above are MQA's claims. Do I have it right so far, or have I mangled or missed anything? Thanks - Boom So basically all DACs should ultimately sound the same?
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Post by Bonzo on Feb 17, 2017 15:31:29 GMT -5
I'm gonna kick back and wait for you guys to figure this all out and have a full understanding of it. And then ask for you to report what you find in 5 sentences. As of right now I'm VERY confused.
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Post by Axis on Feb 17, 2017 15:34:31 GMT -5
I'm gonna kick back and wait for you guys to figure this all out and have a full understanding of it. And then ask for you to report what you find in 5 sentences. As of right now I'm VERY confused. Bonzo, Actually that is your brain working right. Stand back and watch is a very smart move with stuff like this.
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Post by Jim on Feb 17, 2017 15:35:23 GMT -5
MQA is good. It's job stability for all the people that have to oversee the re-encoding process for millions of songs!
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Post by goodfellas27 on Feb 17, 2017 15:39:15 GMT -5
It wouldn't sound the same since the power supply and analog path would alter the sound. In theory, if you have two closely similar DACs specs/design it would sound the same. Manufacturers like Schiit don't like this because a $800 DAC could potentially sound like their top end $$$$$ DACs . Assuming in has closely similar/identical designs. MQA would bypass their DSP coloration "secret sauce" and hit the analog path; hence, they don't support MQA. Mr. Levkof - Correct me if I'm wrong, please: To my understanding, if MQA knows the A-to-D device that was used to originally transcribe an analog master to digital, then (and only then) does the MQA remastering process compensate for the phase damage done by that original A/D conversion. As a second part of the "MQA-remastering" process, the original digital conversion is upsampled to higher bit depth and sampling rate. The third part of the "MQA-remastering" involves using a lossy CODEC to repackage the high treble of the MQA-remastered music for smaller file size. At this point, the MQA file is a "Studio-Master" quality copy of the original analog file (per MQA). Upon playback, however, the MQA-compatible DAC not only "unfolds" the MQA file, but also restores the high treble to its proper place in the file. Additionally, IF (and only if) the MQA DAC knows the specific make, model, and filter implementation of its D to A converter, then the MQA program ALSO compensates for the distortion and high-frequency truncation expected from the playback A/D conversion. At this point, what comes out of the DAC should, in theory (and according to MQA) be a virtually exact copy of the original analog recording that started the whole process, and in full "studio master" quality. Per my understanding, all the above are MQA's claims. Do I have it right so far, or have I mangled or missed anything? Thanks - Boom So basically all DACs should ultimately sound the same?
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Post by Bonzo on Feb 17, 2017 15:41:20 GMT -5
I'm gonna kick back and wait for you guys to figure this all out and have a full understanding of it. And then ask for you to report what you find in 5 sentences. As of right now I'm VERY confused. Bonzo, Actually that is your brain working right. Stand back and watch is a very smart move with stuff like this. Wha-da-ya-know. All the stars are aligned today. Only happens once in a blue moon.
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KeithL
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Post by KeithL on Feb 17, 2017 16:40:37 GMT -5
I believe you're pretty darned close.... with a few minor adjustments. On your first statement.... They originally specifically claimed, as you said, that they could correct for damage caused by known A/D converters in the original conversion process. They have now expanded that somewhat in light of the fact that the original converter may not be known, or that multiple tracks may well have been digitized by different converters before being mixed together. They now claim that their encoder is able to identify certain types of damage directly, and then fix it, without knowing specifically what caused it. Presumably, just as you can often look at a photo and recognize parts that are out of focus, they are able to recognize certain types of "temporal blur" or "ringing" directly. For example, perhaps they pick out pre-ringing as something that never occurs in nature and remove it when they identify it. I've read hints that suggest that the encoder works this way, but that more precise "hand corrections" can be achieved if you do know, for example, the original equipment used. They don't talk about the process in explicit detail - but they seem to be suggesting two levels of correction - automatic and premium. Another thing is that they don't characterize the "high frequency temporal detail" they claim to restore and reproduce better than anyone else as simply high frequency treble. They're claiming this includes both high frequency content (like ultrasonic harmonics) and short-duration time errors (which presumably include both ringing and slight phase shifts). This is one of those finer points that provokes endless arguments. For example, let's assume I have a 10 kHz sine wave in both channels. Assuming that those channels were 36 degrees out of phase, the time difference between the two would amount to about one wavelength at 100 kHz, and would presumably affect where my brain believes the bell to be located in space. Now, many people misunderstand the fact that, even though a CD cannot reproduce a 100 kHz tone, it could still accurately reproduce that phase relationship... but only if we were talking about continuous 10 kHz sine waves. How accurately that 36 degree phase difference at 10 kHz could be reproduced becomes much more uncertain if we were talking about a tiny little bell tone that only contained one or two cycles at 10 kHz. (And that error might manifest itself as a slight shift in the position of the bell, or as it's sounding slightly blurred, rather than as a tiny distinct bell at a point location). THIS is the sort of detail that they're claiming to handle more accurately. In non-mathematical terms they're claiming that they can make the bell sound more natural. And, finally, there's no IF about the DAC knowing the details (*) ... In order for any DAC to be MQA certified, it has to be profiled, and the firmware MQA implementation is then customized to go with it. (On that "second unfold level" there's no such thing as a generic implementation... you either get customized firmware or none...) The exact steps as you've listed them seem to agree with what I've seen claimed - although the exact details seem to vary slightly in different explanations. (For example, I'm not sure that it's even relevant whether they upsample as part of the encoding process.... all that matters is the final sample rate they deliver at.) Mr. Levkof - Correct me if I'm wrong, please: To my understanding, if MQA knows the A-to-D device that was used to originally transcribe an analog master to digital, then (and only then) does the MQA remastering process compensate for the phase damage done by that original A/D conversion. As a second part of the "MQA-remastering" process, the original digital conversion is upsampled to higher bit depth and sampling rate. The third part of the "MQA-remastering" involves using a lossy CODEC to repackage the high treble of the MQA-remastered music for smaller file size. At this point, the MQA file is a "Studio-Master" quality copy of the original analog file (per MQA). Upon playback, however, the MQA-compatible DAC not only "unfolds" the MQA file, but also restores the high treble to its proper place in the file. * Additionally, IF (and only if) the MQA DAC knows the specific make, model, and filter implementation of its D to A converter, then the MQA program ALSO compensates for the distortion and high-frequency truncation expected from the playback A/D conversion. At this point, what comes out of the DAC should, in theory (and according to MQA) be a virtually exact copy of the original analog recording that started the whole process, and in full "studio master" quality. Per my understanding, all the above are MQA's claims. Do I have it right so far, or have I mangled or missed anything? Thanks - Boom
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Post by Casey Leedom on Feb 17, 2017 17:25:15 GMT -5
So KeithL, I'm curious, One of my concerns regarding the MQA Hype Factor is: where are the scientific papers describing the justification for their claims? But is that reasonable for me to want to see? I'm a scientist [at heart] myself, so that's the first Truth Grounding State that I reach for. But maybe in the Black Magic Audio Industry it's okay for a company to hold something as Trade Secret and simply claim that they've discovered the Fountain Of Youth — and, "stop complaining about the bad taste kid", you're ruining my pitch? I guess what I'm asking is, what's the history of other companies developing fundamental new processes and publishing them? (Quite likely after patenting them of course.) Is this done in general or does everyone just trust the Carnival Barker? Casey
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Post by Boomzilla on Feb 17, 2017 17:42:23 GMT -5
I believe you're pretty darned close.... with a few minor adjustments...The exact steps as you've listed them seem to agree with what I've seen claimed - although the exact details seem to vary slightly in different explanations. Thank you, Mr. L - The details may well change more because some bozo like me is trying to explain it rather than getting the exact stuff from the MQA designers. There's LOTS of "MQA garbage" floating around the internet, with lots of folks interpolating and interpreting what they've read. Some confusion is normal as for any complicated new technology. Some is surely the result of people reading accounts from second or fiftieth hand. There's also plenty of curmudgeons about saying that there's just NO WAY that you can make something sound as good as it was originally, and that every successive modification MUST take you farther from the truth. That is highly unlikely to be true. In theory, yes, one CAN retro-engineer back to "better than the original" (which was never the original to start with, but rather some 44.1 KHz sample of same). Now even the original master tape itself could, theoretically, be retro-engineered back to "better than the master." All it would take is knowledge of exactly what distortion, jitter, signal-to-noise ratio that the original recorder had (and what tape characteristics). In short EVERYTHING can be "truer to the original" than we previously thought possible - at least in theory. How well MQA realizes those theories (or not) is still up for debate. What they're trying to do does make sense (in theory). Is it possible with today's MQA technology? I don't know. But if MQA doesn't do the job, certainly some future technology WILL. If it's possible (and it IS), then someone will figure out how to do it. So back to the thread topic. Mr. Collinson of Linn doesn't like the MQA business model. Tough. We all have right to be skeptical of MQA's claims. Fine. But whether or not MQA succeeds as a business, and whether or not the (fully implemented) MQA experience lives up to its theoretical potential, the "better than the master tape" recording IS coming somewhere down the road. And the future's so bright I gotta wear shades! Boomzilla
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