MQA is Vaporware

[John Dyson]

21 minutes ago, Jud said:

 

It varies with people and systems.  I've always thought my Vandersteens (which have linear phase crossovers, and are designed to be time/phase-aligned) sound best with linear phase filters.  Obviously different speakers could change that.

This is an *interesting* discussion to me (about linear phase/minimum phase/etc filters.)  One reason is that the 'ringing' associated with truncating the spectrurm isn't quite the same manifestation as true ringing.  Think about this -- run a sine frequency sweep on a linear/minimum/etc phase FIR filter -- what is the result? (as long as it is desinged to be flat with a cutoff) -- it is flat!!!   Run the same test with a filter that  has true ringing -- it is NOT flat (or has been weirdly compensated -- usually ignore that situation.)  I mention this below -- but going to head off some comments about the mechanism -- SOME OF THE MATH IS SIMILAR, but Gibbs is due to 'waves not cancelling anymore', and 'ringing' is due to resonance.

 

The 'Gibbs effect' ringing is actually a mirage in a way -- the 'ringing' resulting from an LPF  filter is not due to resonance, but is due to residual pseudo-sine waves not being mathematically cancelled due to missing higher frequency components.  IF you don't have a coherent square wave, and remove the higher frequency components, you'd probably not even notice the frequency cutoff (other than the missing higher frequency information and an imponderable difference in the peak value.)  Of course, changing the frequency response changes the peak amplitude of a signal -- in fact, a low pass filter can definitely & counterintuitively  increase or decrease the peak signal level.  The peak level depends on many things, including the relative phase of the components.

 

Where is the 'ringing' coming from then? -- it results from the removal of frequency components where there are residual components left over because the higher frequencies no longer add-in to compensate for the remaining lower frequency components.  This phenomenon is called the 'Gibbs effect' and isn't really ringing due to a peak and resonance.  (Some of the math can be similar, but the actual process is different.)

 

So, what is the difference between the left over residual frequency components moving from different places in the square wave?  It is beause the phase vs frequency is varied, so the apparent locations of the residuals move around.  The energy hasn't changed.  The timing difference is due to a phase difference.  In the case of linear phase, all of the constituent frequencies are delayed the same.  With different kidns of filters, the delays are skewed vs frequency.  In processing of audio -- linear phase filters can be a godsend, because the delay is totally fixed from the lowest to the highest frequency.  This is MUCH nicer than the good old linear filters, IIR, and other kinds of filters which require work to avoid/manage that phase shift (various kinds of things like group delay.)  The BAD thing about linear phase filters is that they have long delays -- minimum phase filters have variable delays, but can be much shorter.  All kinds of FIR filters are also much more CPU intensive than an IIR (e.g. analog filter emulation or magical filter unrealizable in HW) which can get by with a much lower filter order, and much less CPU.

 

What about this thing called a 'square wave', how do you get 'ringing' with the square wave, but there is no peak or resonance?  As I explained above, the 'ringiing' (which it really isn't) is just a left over residual of missing higher frequency components not cancelling the residual away.

 

Why should we care about how the residual components manifest?   I don't know -- I won't make judgements about what someone else hears, but one thing for sure -- electronics acts differently with differing peak signal levels.

 

John

 

 

[John Dyson]

15 hours ago, crenca said:

 

According to Bob S and his supporters such as John Atkinson, you should care because this "ringing" effects "transient behavior".  They don't explain the how/why - they just assert it and then go on to design MQA/DACS/systems around the assertion.

 

 

but but but:  there is NO ringing!!!   That is the frustrating thing, they are basing their idea on something that doens't really exist...  It is a mirage, and have a full ecosystem on mistaking a series truncation for ringing.   So, that is another mark against MQA and the theory behind some of the aspects

 

When doing the series truncation (brickwall LPF), the so called 'ringing' frequencies were in the signal BEFORE the filtering.  The so called 'ringing' happens because of the higher frequencies being excluded, and the 'undulations' that you see  are a residual effect that were ALWAYS in the signal.

 

The signal associated with the Gibbs effect WERE NOT CREATED BY THE LPF!!!  They were made apparent by the removal of higher frequency components.

 

sqwave = x + x^3/3 + x^5/5 + x^7/7..., where x=2*pi*f*t

*Above, I ignored the 4/pi constant multiplication factor, unimportant for this discussion.

 

When you chop off the series above a certain point point -- removing frequencies above a certain point in the series, then you get those weird things that look like oscillations, but NOTHING HAS BEEN CREATED, and has only been removed.

 

John

[John Dyson]

9 minutes ago, Jud said:

 

Nice - I'd read about this before (including one prior comment from you in this thread), but didn't quite understand what you were driving at until now.

It is so very easy to take the idea that Gibbs is the same as 'ringing'.  Everyone (including I) call it 'ringing.'  But, when it comes down to designing DSP software or circuitry, it isn't really ringing -- so needs to sometimes be looked at differently.  For example, it has SOME of the same characteristics that can be created by ringing.  If one looks at it in a different way -- 'ringing' in the correct circuit can massively increase the signal level -- but Gibbs is limited to a few percent (AFAIR about 9% -- I could be wrong -- I get things confused like everyone does.)  I promise you -- even EEs get tripped up by this one, mostly because it is often called 'ringing'.

 

This effect is one reason why  sometimes on digital systems it is a good thing to leave some wiggle room when normalizing a signal.  If there is a subsequent LPF, then the overshoot will cause fewer problems.   Ringing can still cause problems, but allowing for a linear phase overshoot is probably a good 1st cut rule.

 

The REAL problem with Gibbs is if there is a conversion to analog or the digital signal hard limits (or wraps around) at full scale, then a multitude of evils can happen.  Analog electronics can be susceptable to increases in distortion also.

 

John

[John Dyson]

39 minutes ago, crenca said:

 

 

Devil's advocate says:

 

You say potato, I say potato.  Whatever the definition and source of said "ringing", Bob Stuart, @John_Atkinsonand @Jim Austin maintain that it is relevant, and effects in band sound quality through "transient behavior".  Who are you?  Your not a recognized authority.  As AQuint has explained, your understanding is political.  Indeed, as @Jim Austinexplicitly said, your part of a herd and "nasty" (his word) forum mentality.  If only the @The Computer Audiophile would reign in this thread, forum, and consumers in general your misinformation and silly explanations would not cause and baseless and unneeded controversy around a perfectly good product like MQA.

 

in other words, of course ringing effects transient behavior...

 

Who am I -- the only person who has written (successfully and reviewed by audio pros) a DolbyA decoder.  Much more tedious than even compression routines -- working from ancient HW schematic designs -- NO SPEC!!!  Being a full practicing EE & Software & DSP person for many years makes me an appropriate person to do these kinds of projects. 

 

I am an engineeer and SW developer with 40yrs experience,  at least 1/2 at AT&T Bell Labs, an OS developer (wrote a big part of the original FreeBSD kernel -- refer to the copyrights in the source), and also a DSP developer who knows what they are doing.  As EE's go, I am pretty good also -- one of the few left who can ACTUALLY DESIGN, not just mimick temperature compensated and stable circuitry with what ever transistor kind of device that you might give me to work with.  Also, I do have a background (somewhat fuzzy) in vacuum tube design, but find little use any more other than as a curiosity.

 

So much for the introduction:

 

All you need to do -- look at the series, and see what happens when it is truncated.  It is technically NOT RINGING, but is a residual from a truncated series expansion...  Simple as that.  Think about what happens when a brickwall LFP does its thing...

 

As I wrote above, I informally call it 'ringing' also, but it is NOT RINGING.  Hearing effectively does a spectrum analysis -- hears something like sine waves, and when you hear a square wave, you hear the fundamentals and the harmonics -- NOT A SQUARE WAVE. 

Your hearing doesn't hear 'SQUARE WAVES', rather it is a kind of spectrum analyzer (I hesitate calling it a fourier transform, because it is not.)  So, a truncated spectrum only takes away spectrum that one cannot hear much of the time anyway.

 

It is NOT a resonance, but a truncated spectrum.  It is called Gibbs.   Yes, there is some math in common -- but there is a LOT of math that has common roots, but are different things.

 

John

 

[John Dyson]

BTW -- I do not like to toot my own horn.  I have a very minimal ego -- just enough too keep me from needing to compensate for an inferiority complex. :-).  I use the pronoun 'I' A LOT, not because of an ego thing - -simply because of all of the fun things that I can do -- I suck badly at writing.   WRT producing written text, I am barely literate.  Thank God for my project partner -- he is exquisitely literate, and is excellent at bridging the deep technical details.

So -- I DO APOLOGIZE for using 'I' too much.   It is a matter of limited composition skills.

 

John

[John Dyson]

10 minutes ago, crenca said:

 

Why John do you think that Bob S, John Atkinson, Jim Austin, Stereophile, TAS, and almost all of the lessor audiophile press were so easily able to convince with their "ringing effects transient behavior" narrative? Even before MQA this narrative was very common and, mostly, assumed to be real and correct, though debates were to be seen occasionally here and there.  

 

Again, playing devil's advocate:  While I believe what you say is true, I don't see how this truth matters.  It's just common sense, everybody knows that ringing is a significant factor and that MQA is a (even if not "the") solution.  

 

My answer to the question:  Audiophiledom is not about the truth.  It's a myth based culture, and the culture has authorities.  Your not one of them, and John Atkinson is.  

First -- I DO MAKE MISTAKES, and I am just as susceptible to myths as anyone else.  Geesh -- I used to believe that 'Gibbs' is really ringing for many many years -- until I put my EE/DSP hat on instead of my 'just me' hat.  It is so easy to be mistaken in these highly technical fields, and one thing that I have learned to say (or write):  yes, my statement was wrong, I was wrong in my beliefs, etc...  (I am not wrong about Gibbs, but I have been wrong about A LOT of things. 🙂)   Threw the stupid part of ego away -- once I did that, it was so much easier to be intellectually honest and accept the truth.

Another thing -- gotta give up on trying to convince those who don't want to admit the truth.  I remember an old co-worker, a little long in the tooth, telling me that he was a real expert in this or that field.  In fact, he said:  I can't be taught anything!!!   He really said that, I was incredulous and kindly kept my mouth shut :-).

Stupid arguments are not worth throwing away friendships or even kind correspondents.

 

John

[John Dyson]

11 minutes ago, The Computer Audiophile said:

 

 

 

I'm having a hard time following you here. Are you really going after John Dyson or are you joking? 

I can tell -- he is pretty much accepting, but also trying to figure out if I am full of manure.  I saw it as a kind jab, not an insult.  At first it took me back a little, but I truly can understand questioning 'this stranger' here :-).

 

There are charltans out there -- and frankly, I could just as well be one (how can you tell?)  I respect it when people try to figure things out.

 

 

John

 

[John Dyson]

1 hour ago, mansr said:

The music labels are part owners of MQA. Part of the licence fees paid by the hardware manufacturers thus goes to them. Post edited to clarify.

I agree that is part of the whole picture -- it is pretty clear that it is all about the Benjamins...   Another revenue stream isn't all bad for the record labels, along with a bit of a siphon for the MQA license patent holders.   Transferring more 'Benjamins' from the music lover to the intellectual property owners (without increasing the quality or quantity) is all bad for the music lover/consumer.

There is ZERO upside to MQA for the consumer.  There is even some upside for the propagandists (whoever they might be.)

[John Dyson]

2 minutes ago, tmtomh said:

I have to say, I largely agree with @John_Atkinson here. I hope MQA remains a niche product (or better yet, dies out quickly). But as long as it's here as a format in the audiophile world, it's to be expected that MQA files will show up among those used and mentioned in equipment reviews.

 

Should Stereophile have an editorial policy forbidding reviewers from using MQA files to audition digital source components that do not have MQA support? I would say so - although the fact that non-MQA equipment still can play MQA files (as opposed to DSD files on PCM-only equipment) makes it a grey area. And I am guessing the culture at Stereophile is one in which editors prefer to give reviewers latitude and autonomy and don't typically issue flat-out prohibitions like that to the reviewers.

 

But while reasonable people can disagree about the above question, the notion that Atkinson is quietly pursuing an agenda to promote the benefits of MQA by slipping MQA files into reviews of non-MQA-capable equipment, with the idea that the non-MQA gear will be viewed as deficient in features or the MQA files will be called out as not sounding as good as they do when played through MQA-capable equipment, is IMHO ridiculous. 

 

And as I've said many times before, what makes such conspiracy scenarios particularly silly is that they're not even necessary in order to support the opinion that Stereophile and other audiophile publications have not been sufficiently clear or balanced in highlighting and attending to the flaws in MQA's technology, the misleading nature of MQA's PR and listening demonstrations, and the predatory implications of MQA's business model/aspirations.

 

Frankly, my only interest in MQA is as a curiosity that tries to sell itself as something superior, while it is inferior (or equal at the very best.)  It is only a distortion mechanism, and an anachronism -- who cares about a few percent of space savings -- and getting a lower quality result at best? The manure about the 'blurring' or whatever technically unsupportable claims of 'advanced' technique or technology is only meant to astound or confuse those who haven't spent their lives understanding what is really going on in digital processing.  The claims about MQA certainly confound those who know that the 'spew' about MQA is nonsense...  How can a competent/honest engineer even advocate this mess?  Money, right?  Claiming one thing, and knowing another just isn't a nice thing to do.  (First time I hear about Gibbs ringing in a serious technical discussion -- not in casual communications -- I know that the person just doesn't understand or is purposefully deceiving.)

 

The only 'blurring' with a linear phase LPF is the fact that it is an LPF, and has a fixed time delay...  Period.   There is a blurring of a kind when not using linear phase, but it is only because of the time skew vs. frequency (phase shift vs. frequency.)

There just is ZERO purpose to MQA for the consumer who wants quality, and it seems that fact gets lost everytime there is a discussion.  Turn us back 10-15yrs, then there might be a benefit of moderately low distortion compression -- but who cares nowadays?   For more casual situations using cheap transducers, then mp3 can probably work well enough (many of my own processing software  results (pro use only) TOTALLY blowsaway the capabiliites of mp3 at 320k -- that doens't mean that mp3 isn't good enough for casual listening.)  mp3, aac, opus (or the lossless flac) seem to fit all of the various kinds of compression needs -- without limiting access to the recording.  For my project/product, I cannot get by with dishonesty of any kind -- the pros are not easily misled (at least for very long at all.)  The consumer realm is ripe for being misled.

 

So where does MQA have a marginal benefit?  Certainly not at home, where higher quality is desired &space not important, for casual listening?  nope, no real reason for MQA there either.  Maybe MQA is good for the (short) walk between the front door and the car? :-).

 

What is the real reason for MQA -- revenue -- more Benjamins drained from the consumer...  Those advocating MQA obviously have some kind of occult (as in hidden) interest -- there just isnt'  a useful consumer technical benefit anymore.  There is a benefit, but not to the consumer.

 

John

 

[John Dyson]

16 hours ago, tmtomh said:

 

Well-said - and amen!

 

I would only suggest one partial qualification, in regards to your "occult" comment: I have no doubt that MQA's interests are mercenary (especially given the major labels' reported 20+% ownership stake). And Stuart et al's way of promoting MQA does indeed seem to be deceptive and misleading, regardless of the specific psychological and financial motivations behind it.

 

 

I admit that using 'occult' or 'hidden' might imply a conspiracy that doesn't exist.  Maybe I have assumed the MQA community to be more organized than it really is.  The continual repeating of the same gobbledy-gook made me think that there is more coordination than there really is.  The similarities are probably not due to hidden communications, but often due to incorrect 'common knowledge' and damaging memes.  

It IS the responsibility of publishers to go the extra mile to be skeptical when distributing information represented as fact, when it is actually mixed with opinion or (common knowledge.)  An incorrect fact can be mistakenly passed amongst the press (back and forth) until it becomes an incorrect common knowledge*.

 

*  BTW -- not everything stated about some of MQA's technology is wrong, but some 'facts' are so far off, that they worry me about some of the rest of the 'technical know-how' in areas where I am NOT well versed.  I certainly DO NOT know everything, so -- unlike some 'experts', I TRY not to represent things that I do not factually know as an accurate fact.  Even though I am FAR from perfect, this thing called 'integrity' is important to ALL of us.  We do sometimes forget and DO make mistakes.  There is room for forgiveness.

 

John

[John Dyson]

1 hour ago, Currawong said:

 

I can't edit my post to fix this for some reason, but it looks as if this was a bug, as it now syncs without issue.

Windows has regularly frustrated me in trying to create demo CDs (not to be distributed) -- but I have ways around it.  However, when not even violating the fair use, they clamp down too much.  Pretty soon, we will be paying something like 10 cents every time we play a song for our own enjoyment. (might be exaggerated -- but in essence it is the reality.)

 

There are already 'helpful' broadcast protection schemes, and that should be enough.  The non-fair-use advocacy is trying to destroy every bit of freedom to get every last dollar (pound, Euro, etc) that they can get from us.

 

John

[John Dyson]

46 minutes ago, John_Atkinson said:

 

More misstatements. No-one at Stereophile is paid by the word. In addition, as Art Dudley is a fulltime Stereophile employee, he gets paid regardless of how much or how little he writes.

 

And on the sound quality of MQA, a manufacturer was delivering a product for me to review recently. Once we had installed his product, he asked to hear some music. I played some of his files with the dCS Rossini DAC but then played him 3 versions of the same song (peak levels were identical): the original 24/88.2k master of one of my recordings; the MQA version unfolded by the Rossini; and the CD-resolution version from the commercial release. His ranking was the same as mine: CD was okay but somewhat uninvolving compared with the hi-rez master, with a less deep soundstage; the MQA version was tonally identical to the master but better resolved the soundstage with the acoustic objects within the stereo image having somewhat greater palpability.

 

 

Who cares about CD for the best quality -- just get 24bit at least 48k sample rate -- no need for recording obfuscation?  No need for excessive control/royalties for patents/stifling innonvation, etc.  No need for more centralized control.  There are already broadcasting protections, and a few schemes to impede common folk to copy while using their favorite communications sites.

My current bandwidth is 90Mbps download -- fast enough to grab anything that I want.  My upload is 12Mbps --low enough to keep me from much broadcasting much directly from my machine (not that I would ever wish to do that.) (I guess I could write a cloud app -- but really

SO, why mess with the audio, to save some space, when it isn't needed.  If the CUSTOMER wants to save space, there are adequate methods.

Again, why MQA?  Answer:  Benjamins (or is it Benjamines :-)).

john

[John Dyson]

1 hour ago, Shadders said:

Hi,

If possible, can you comment on the impact of MQA on the blossoming market of DSP room correction, and other technologies, where the removal of access to the digital audio data stream means that those products are rendered useless.

 

 

I think that you are describing a very important opportunity that is destroyed by MQA (unless resolved to analog/convert to digital/process/convert back.)  That is an audiophile's h*ll..  MQA simply restricts options, takes away usefulness, takes away casual/legal forms of freedom, takes away whatever amount of money, take take take take, limit limit limit.  The 'goodness' in MQA  would mostly be anachronistic.

Well, MQA would also make unpleasant long discussions between technophobes, technophiles, and the technically very competent.    Those discussions are usually very frustrating, mostly useless, and sometimes antagonistic (even grownups can let themselves get trapped in those messes...)

Bottom line -- it just isn't for today -- maybe yesterday, but not today.  If MQA was done yesterday, today we might have had a much more restrictive, limiting audio world.  Certainly the audio quality would be no better than it is today either.

 

John

[John Dyson]

17 minutes ago, John_Atkinson said:

A search on the Stereophile website for the phrase "this stuff works" didn't throw up anything to do with CD StopLight, so I looked in the back issue archive and found this about CD StopLight in the October 1992 "Recommended Components": "'This stuff works' reports JE [Jack English], PvW [Peter van Willenswaard], and JA [John Atkinson] . . ."

 

 

Kind suggestion -- please dont' let yours (or any) publication to be used for political/raw profiteering purposes (unless it is a paid advert.)  Opinions are okay, if appropriately labeled.  It is SOOO difficult nowadays, because opinions are so often conflated with accuracy (sometimes opinons are accurate, but even then should be appropriately labeled.)

I don't know how to make sure that people are 'straight' (I mean in the truthful, integrity, knowledge sense, not in personal attributes), or confused.  I guess that is where expertise in editing and double checking comes into play.  (The major news media in particular hasn't been very good about having/practicing with integrity lately -- and I hope it doesn't get worse.)

 

John

[John Dyson]

1 hour ago, mav52 said:

r

 

1 minute ago, firedog said:

Why not, I thought it was established that it increased (apparently) euphonic jitter? 

Unlike laserdisk, there is no jitter from the platter that can be propagated.  It is similar to the jitter in the internet.  Internet 'jitter' can be seconds, yet we all can listen.  The 'jitter' or speed variations are taken care of by buffering.  Then only actual jitter is in the last D/A in the chain (whatever clock noise, D/A noise, ground noise that there might be.)

The data is effectively purely digital without slight differences when the timing changes (as long as the data stays in the detectoin window.)  Laserdisks on the other hand were analog, and the speed variations (without time base correction) would be reproduced on the TV screen.

Laserdisk timing wasn't good enough to directly connect to my super duper high quality D9 decks, I used a DPS290 TBC to convert the unstable laser disk to stable broadcast timing.

CDs, on the other hand, are 'time base corrected' (effectively.)  The jitter in the system is associated with your last D/A (or grounding/etc as I mentioned above.)

It is SOOOO easy to fool oneself with listening comparisons...  I also fool myself with audio comparisons from time to time.  IT is incredibly difficult to do correctly.

 

John

[John Dyson]

3 hours ago, mansr said:

Was it though? I'll I've ever seen is a grainy video with a blurry photo of a fuzzy scope image with no scales on the axes and no explanation of what was being measured. That is hardly proof of anything.

Sometimes -- if there was reallly noise, there can be ground noise that is mistaken for jitter.  It is a really difficult problem -- mixing analog circuitry (esp high precision analog) with digital.  It is very easy to create myths to explain away all kinds of behaviors.  The biggest problem for non-technical people (I don't mean non-audio people, I mean people who aren't the EEs who really understand) is that there is a LOT of misinformation, and a lot of misinformation feeding on misinformation.  Eventually all of the mistaken falsehoods become true?  Well, I dont't think so.  However, there are apparently a lot of people solving the 'jitter problem' (which if really solved, is keeping grounds properly separated , making sure that the clock isn't noisy (which can be caused by noisy ground), and good quality components.)  Jitter doesn't have very much to do with the digital signal -- it lives in the analog world and directly in the conversion process.  Of course, when clocks jitter -- the process of creating the digital clock IS analog, and ground noise can modulate the clock (PM/AM type noise.)

Then, after the board is properly designed, bypassed, etc -- finally the noise source is the same kind of thing that creates hiss in any amplifier -- the oscillator (usually high frequencies) will be modulated by the transistor (and other circuit) noise sources.  Sadly, usually high frequency transistors have poor low frequency noise performance -- so it is an interesting challenge to produce a low AM/PM noise oscillator.  There ARE some tricks, but the bottom line is that after all of the outside physical noise sources are resolved, then the transistor noise itself becomes an issue.  JFETS are a little better in this regard (LF noise) because usually a JFET has good HF and LF noise, while high frequency BJTS tend to have high LF noise.  (TOO MUCH REAL TECH HERE!!!) :-).

This clock noise thing does legitimize a separate clock device (if it is done correctly.)  Separating the ground is crucial, and if the circuit board(s) aren't designed right, then the digital world (as noise) will interfere with the analog (but not-so-much the other way around.)

 

John

[John Dyson]

1 hour ago, The Computer Audiophile said:

Come on archimago, sandyk admits to major hearing damage yet still hears differences between bit perfect MD5 identical rips 😄

Ask sandyk how well I passed his evil test :-).  It was tricky, but apparently I did pretty well.   (The difference was something like what I deal with on the DA decoder, so I just happened to be tuned to the sort of difference that was in the test.)

 

[John Dyson]

43 minutes ago, Currawong said:

 

Myself, and others, have been saying this for years. I think this is where much of the problem lies. If the baseline quality had been this to begin with, I reckon most of the arguments over digital wouldn't have come about in the first place.

 

 

"According to legendary musician and record producer Don Was, now president of Blue Note Records, "what record producers and artists intend for the audience to hear is the first commercially released issue—not some hypothetical master tape or enhanced later version. By that sensible measure, every remastering, reissue, or change in format—whether from 78 to 331?3rpm, mono to stereo, LP to CD, CD to hi-rez, or hi-rez to MQA—is simply a lower-fidelity interpretation of the original. That's why I've never felt comfortable with remasterings."

 

T

When I test my decoder with ABBA, I use original vinyl rips for a reference.  (The DHNRDS still sounds much better without vinyl processing -  but I try to make sure that it sounds plausibly the same.)  I agree with trying to sound like the original release.  (Direct DolbyA decodes don't always sound like something that you'd want to release to a consumer, however.)

 

[John Dyson]

50 minutes ago, Currawong said:

 

Myself, and others, have been saying this for years. I think this is where much of the problem lies. If the baseline quality had been this to begin with, I reckon most of the arguments over digital wouldn't have come about in the first place.

 

That is partially true, but honestly -- a lot of material is released without DolbyA decoding.  Ask sandyk about some examples that I demoed.  He didn't like all of them, but I think that anyone (incl him) would say that there was a rather substantial improvement.  The biggest problem when demoing, is that playing through the DolbyA with raw material is NOT all of what mastering needs to do.

 

Undecoded stuff, with a little EQ is sold as consumer material (retch!!) (Compressed highs, flat spatial relationships -- sound famiilar?)

 

Take the HDtracks Carpenters album, do a bit of EQ (to recover original material), and do a DolbyA decode -- sounds really nice.  (I think that album needs +3dB@3kHz/Q=0.707...  I don't remember, it might be +5dB instead.

 

It is heartbreaking that some amount of this digital hatred comes from non-mastering (playout of master tape with EQ is a lot cheaper than doing a DolbyA decode.)

 

John

[John Dyson]

4 hours ago, shtf said:

 

You're right, Archimago.  Listening skills are important to discuss.  And yet, for the last few decades it's the one thing most taken for granted in this audio-only industry.  In fact, I've little doubt it's the number 1 reason why not a single industry controversy can ever be put to rest because everybody is all over the map.  Hence, whenever a new thread pops up comparing formats or analog vs digital or tube vs SS, etc  it's just deja vu all over again without a consensus ever being reached.

 

1.  It seems these days many/most believe that listening skills are inherited at birth rather than a skill that develops over time.  But that would be like saying we're all born to be connoisseurs of fine art because most of us were born to see and we've all visited an art gallery or two.  I don't get out much these days but even when I did, I can only think of a handful of professionals and enthusiastics who possesed well-enough trained ears. 

 

Training is SOOO important.  Just as an example -- 3yrs ago, I could barely detect many kinds of distortion, barely detect the sound of compressiion (the AGC style) & expansion, and probably needed much more than 1dB frequency response variation to detect a difference in frequency balance.  I wasn't deaf, but close to it :-).

Because of raw motivation, I had to learn to listen -- even 1yr ago, I was too insensitive to cr*p in the audio.  Does this ability take away some joy in listening?  YES.

IMO, it is best to be blissfully ignorant, and enjoy the music.  Being very picky and knowing the 'bad sound' does'nt create happiness.  Think about the garden of Eden...

My guess it that even though training is important to actually detect defects, there is an element of natural talent (I used to have REALLY perfect pitch, could name notes from just the sound, but I was never into playing instruments or singing really.  The ability to detect pitch was a natural gift.)  I lost that after high school -- apparently I had the 'equipment', but fell into disuse

Some people MIGHT not have the abliity, but maybe it IS all training.  All I know is that training made a huge difference for me.

John

[John Dyson]

1 hour ago, mansr said:

What test are you referring to?

There was a test with a contrived checksum.  It was meant to confound.

 

1 hour ago, mansr said:

What test are you referring to?

No test -- I was fooled.  This is exactly one of the problems with comparisons -- even someone who can hear differences will sometimes hear differences when they do not exist.

 

I admit a screwup!!! :-).

John

[John Dyson]

8 minutes ago, mansr said:

Differing files crafted to have an md5 collision, or identical files with headers/padding altered to produce different checksums?

I was wrong -- I was told something and believed it (after thinking that I heard something different -- I fooled myself there, and do it all of the time, must be very careful.)   I ran a complete check of the file, and both versions were 150% identical.

Mark one up for my own lack of being careful.

 

John

[John Dyson]

1 hour ago, kumakuma said:

 

I'm confused. Alex appears to be saying that you heard differences between two identical files.

Don't be confused -- that is correct.  It was the mindgame problem that I have written about before.  Even though I can hear real differences, there is something that makes me hear a difference when there isn't one.  Probably because the way that I focus on individual aspects of the sound -- and when it isn't ignored, then I hear the difference.

This is one of the reasons why a statistical way of comparing is much better (but much more tedious.)  I only did a casual comparison, and because of perception issues -- I DID HEAR A DIFFERENCE THAT WASN"T THERE.

 

John

[John Dyson]

2 hours ago, shtf said:

 

But how can you be certain this time the difference wasn't there?  What about the times there was a difference and you didn't hear it?

 

Just askin'  

I tend to focus on individual aspects of the sound.  Since I have been working on the DA decoder, I have to listen for each kind of distortion or 'problem' every time that I listen.  I cannot hear all of the problems at once -- often I will play a bad section of a recording at least 3 - 5 times listening to various aspects.  For example -- on a percussion test, there are some bongos.  I have to make sure that the sound of the slap is correct (including tone and impulse) along with the ambiance after the slap.  There are a few time periods of ambiance -- immediate and longer term.  The decay must also be correct.

I do not have the luxury of listening for enjoyment, but listen for analysis.  Sometimes I do make mistakes, for example I find that evening my results are almost random.  Also when doing serious evaluations, I check several times -- sometimes over a few days.

As I implied before -- DO NOT RUIN YOUR HOBBY.  Don't worry about every last bit of frequency response error, distortion from DolbyA (which will cause unpleasant loss of detail),  or damage from any other kind of processing.  A compressor can REALLY screw up the sound, not just the dynamic range, but also creates dynamic distortions that are simply ugly.

I NEVER implied my hearing is perfect, and in fact -- I know that it is very imperfect, very variable, and very dependent on my mood.  In the case of the test that I did an 'amazing' thing finding something that isn't there -- par for the course. :-).

 

PS:  my listening has eventually been succesfull -- take a listen to the decoded versions of three songs over in the test recordings discussion.  (I limited the examples to be short enough not to be a bad citizen -- wish that they could be longer.)  If you listen to the original versions of So Long (for example) both on vinyl and the CD versions that I have heard -- there is a serious loss of HF transients and the vocal 's' sibilance is weak on the originals.  The DHNRDS decoded versions are much cleaner (but also show more defects in the recordings.)  There are heroic efforts in the DHNRDS to avoid IMD -- the big bugaboo in things like DolbyA.

 

 

 

John

 

[John Dyson]

7 minutes ago, sandyk said:

 

J

One thing I'd like to have some day -- is a 96k master of it.  With the master, and the apparent clipping of the high end on her voice, I am wondering if the brickwall needed for the 44.1k sample rate might be exciting some of the evil Gibbs effect.  This effect might make the hardness of the vocal even worse like what we might be hearing.  This harshness in Carly's vocal is potentially one reason for using a softer rolloff than the typical brickwall when doing downconversion (these is all conjecture.)

 

I might check HDtracks and see if they have a Carly Simon recording...  The only risk (for me) is if it isn't DolbyA encoded...  I only want to purchase leaked material because of limited funds.

Oh well -- yes,  your ESR version does sound better to me.

Sorry again for taking so long to respond.  In the midst of mental decompression right now.

 

John

 

On Friday, March 22, 2019, 7:50:09 PM EDT, John Dyson

 

I removed a large section of a conversation that was intended to be personal.  But it does show how hearing can be fooled, doesn't it?  Please listen to the demos on the 'test recordings' subforum -- AFTER A LOT OF INTENSIVE WORK, even after getting all of the easy to measure details correct -- things like attack/decay are incredibly difficult to make correct.

 

 

I know about depression -- it is a really terrible problem.  It is silly to say please feel better -- because depression is something that is often impossible to control.  No matter what, my intention is that I hope you do feel better.

 

 Anyway -- when I did the comparison check, on the non-B and the B versions, of Carly's recordings -- earlier today,  I did a bit for bit comparison of the entire file.  They were identical.   I was fooled!!  No biggie, I never claim to be perfect!!!

 

It is SOO easy for hearing to be confused.

 

John