33 thoughts on “MQA: The Day After

  • December 5, 2014 at 11:49 am
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    ‘Another critically important factor (and one that I’ve failed to acknowledge in previous posts) is the resolution of human hearing in the time domain. There is new information that accuracy in the time domain is multiple times more important than the frequency domain. I’m not sure where the cutoff is for this level of accuracy but I’ve read and heard that 5 to 10 microseconds is the range. This requires a sampling rate of 192 kHz…according to this new information 96 kHz/24-bits is not sufficient.’

    I fail to comprehend this in the context of the Nyquist-Shannon theorem. I will need more theory to convince me. All this sounds (i.e. the youtube stuff and the announcement) like science interspersed with marketing mumbo jumbo. I have no problems accepting that this compression method provides excellent quality with reduced bandwidth requirements / file size. I just feel the whole thing is presented in marketing speak. Is it lossless or isn’t it? Is ot psychoacoustics or not? Frequency vs Time domain??? We will need more time to tell and distinguish fact from fiction. There we go again…

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    • December 5, 2014 at 11:55 am
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      Forgot to mention that last time I checked I was studying digital speech processing thus it was looooong ago, frequency domain and time domain were just two different ways for expressing the same thing. Well, maybe things have changed since then but somehow I doubt it.

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      • December 5, 2014 at 2:07 pm
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        You’re right they are related…very closely related, which is why I’ve always focused on the frequency side.

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        • December 5, 2014 at 10:00 pm
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          I’m not saying they are just related. I’m saying they are exactly the same thing expressed differently. You just look at the same thing from a different point of view. You can convert from the one to the other using mathematical transformations (one usually chooses to deal in the freq domain since the mathematics are easier). Now, whether engineering problems (i.e. introduced errors = noise) arise during implementations, which partly invalidate this tautology lies beyond my knowledge domain. This might well be the case, which might explain why frequency vs time may need to be tackled differently in order to represent the one rather than the other with better accuracy. But all this is engineering not theory as far as I understand it. It may well be the case that I’m mising some fundamental thing here so I’m all ears (sic).

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      • December 5, 2014 at 5:48 pm
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        If a signal has a rise or fall time of 5 microseconds, that represents a bandwidth of 68 kHz for that content. It makes sense that a sampling rate of 96 kHz is too low.

        The frequency and time domains are related by using Fourier transforms or Laplace transforms. I’ve spent my engineering career working with both on a regular basis.

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        • December 6, 2014 at 1:04 pm
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          Thanks Dick…I’m not ready to throw in the towel on 96 kHz/24-bit PCM…if the rise or fall time is 10 microseconds that would be 38 kHz and 96 kHz handles that just fine. Right?

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          • December 6, 2014 at 4:08 pm
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            You mean 34 kHz. The relationship is linear.

          • December 6, 2014 at 4:12 pm
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            Of course! I should use a calculator! Thanks.

        • December 6, 2014 at 11:17 pm
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          Of course. Talking about time domain as if it was a different thing than frequency domain makes no sense to me. The 5ms = 68kHz signal is, after all, a 68kHz signal which just happens to last for just one cycle! Yes, one the same xxkHz signals we have already spent years debating(?) whether they are audible or not…

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          • December 7, 2014 at 9:39 am
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            Nik…the higher sample rate benefits more than just the higher frequencies…less trouble with filtering, less pre-ringing (and post-ring) on transients.

        • December 7, 2014 at 2:14 pm
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          Interesting, Laplace transforms are a simple way of solving some ODE’s, nothing special otherwise. Surprised they’re being mentioned in the same breath as Fourier, maybe you should clarify.

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          • December 8, 2014 at 8:25 am
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            Dave, I can’t pretend to be a math expert…I learned about Fourier and Bessel functions in grad school when I studied computer music but not in great depth. I’ll have to investigate.

          • December 8, 2014 at 2:47 pm
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            Apologies Mark, the question was aimed at Dick James. BTW, what were you using Bessel functions for; I used them for partially solving PDE’s.

    • December 5, 2014 at 2:07 pm
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      There is undoubtedly marketing speak on the website and in the videos…however, the paper and the patent documents are chock full of compelling information.

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  • December 5, 2014 at 12:49 pm
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    Apparently even people like Robert Hartley of Absolute Sound, with all of his critical listening experience and hundreds of thousands of dollars of listening equipment are not immune to the placebo effect — witness his description of the earth shaking revolutionary sound quality of the new MQA technology. To be honest, I don’t understand how a sophisticated listener like this can imagine that a technology which does not improve on the source material but only the packaging of that material somehow sounds transformationally better than the original CD or LP. What is going on here, and what does this say about all the other reviews in his magazine?

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    • December 5, 2014 at 2:10 pm
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      Robert is a very good writer, knows a lot about audio engineering, and is the head of a successful magazine, however he’s somewhat stuck in the trap of writing about audio. It’s the same flowery language and overblown descriptions…and about a recording done 50 years ago.

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      • December 6, 2014 at 4:10 am
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        To be fair that recording was probably subject to a lot less processing than a modern recording and, despite the limitations of the equipment of the time, might have benefited from a “simpler is better approach”.

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        • December 6, 2014 at 1:09 pm
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          The MJQ recording is a terrific recording done when analog and simple ruled the day. My point is that it didn’t improve when processed through MQA. You got the same fidelity ast he original analog tape played on a great deck and system…and a high-resolution PCM transfer using great conversion etc would equal the analog tape or MQA version. The only advantage the MQA offers is a smaller footprint.

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          • December 7, 2014 at 4:04 am
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            ….and it the great question, whether this ‘small footprint’/the smaller size will engage more people for downloading/paying/listening to higher res’ed files?

          • December 7, 2014 at 9:41 am
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            If MQA is a completely transparent process of encoding and decoding, then it will make high-resolution files more accessible. The key question still remains whether anyone will care and whether the artists and labels will start making better sounding recordings.

    • December 19, 2014 at 6:14 pm
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      Isn’t there the possibility that their ADC is producing a better result than what is used today? Hasn’t ADC had vast improvements since the introduction of the CD? Is that what Robert Harley is hearing?

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      • December 20, 2014 at 3:51 pm
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        I doubt it. I don’t think Robert is actually hearing anything new…he’s writing about the sound quality when MQA is not about sound quality. It’s about making files smaller without any loss. Yes, ADC have gotten better. But they’ve been good enough to handle analog recording fidelity for a long time.

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  • December 5, 2014 at 2:40 pm
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    I was always told that the human heard sounds as coincident if they were separated by 18ms or less. And that 27ms was the threshold for easy distinguishment. What has changed?

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    • December 5, 2014 at 3:32 pm
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      I can’t honestly say that I’ve done extensive reading on this…but the new numbers I hear are 5-10 ms.

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  • December 5, 2014 at 3:26 pm
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    Isn’t FLAC “small enough to download or to stream today” ?! That format is only just becoming established in a mainstream sense: a new format war could have more people choosing neither, rather than buying into it.

    Much is made of Hi-Res involving frequencies above the range of human hearing. However, have there been any proper tests as to whether some of these high frequency sounds can sympathetically affect much lower ones, even in the bass?

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    • December 5, 2014 at 3:34 pm
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      It depends on the specs of the audio that is placed in the FLAC container. There have been some proper tests that establish that there are very real benefits to higher sample rates…whether we “hear” the ultrasonics or not is another thing.

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  • December 5, 2014 at 4:49 pm
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    If they mention “psychoacoustics”, then it means the format is not lossless. I’ll pass in favor of ALAC and FLAC, thank you very much. Then again, I have zero interest in streaming.

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    • December 5, 2014 at 5:08 pm
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      This is a lossless encoding/decoding process…and the nature of the scheme was informed by studying psychoacoustics and neuroscience…according to the information I have read.

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  • December 5, 2014 at 6:05 pm
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    It’s dang near 2015 and bandwidth speeds – storage space are no longer major issues for the majority of us.
    What is a problem is industries profits. Besides the software the hardware people need a new “got to have” product to sell. So now we have a new compression system you’ll just have to buy.
    Stewart asks about Stereophiles Robert Hartley’s comments that the new system makes huge audible improvements when we know this is technically not possible. Just more snake oil my friend, Stereophile has to support its advertisers if they expect the advertisers to support them.
    It’s sad that a fantastic advance in audio like digital has led to the biggest explosion
    in BS and snake oil that this industry has ever seen..

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    • December 6, 2014 at 1:06 pm
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      Clearly, the MQA development is important. If Meridian has really figured out a way to stuff 11 pounds in a 10 pound bag within existing formats, then we’re closer to streaming HD-Audio. I think that ultimately where we’re headed. But the whole think hinges on better quality to start with and that’s simply not happening.

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      • December 7, 2014 at 4:14 am
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        Having to buy new hardware/new licences just because Meridian can ‘stuff 11 pounds in a 10 pounds bag’ – no way!

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        • December 7, 2014 at 9:42 am
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          If you’ve already got download from HDtracks or others that you like in PCM, there is not need to adopt MQA.

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  • December 29, 2014 at 3:48 pm
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    “I can still vividly recall the delicacy, ease, and resolution of the cymbals in the MJQ piece. I was also struck by the precision of their placement and how they appeared to float in the air against a completely silent background. The treble was totally unlike any other digital I’d heard, completely free from the metallic hardness and artifacts we assume are part-and-parcel of digital audio. Instrumental timbres were so naturally rendered to be almost eerie in their realism. Voices had a stunning palpability and immediacy that were all the more realistic for their compact image size and the sense that they were surrounded by a natural acoustic.”

    Sincere congratulations, you’ve just re-invented the yeast-grown sounding Upsampled MP3s which, as long as I listen to them, feature real-world sound sharpness & density, absolutely silent background {while being played through a very advanced Class B power amplifier}, 120 dB dynamic range, precisely focused 3D soundstage, nearly extreme detail & a degree of refinement {gloss} somewhat higher than DVD-A. Well, actually, there should be much to improve upon them.

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