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208.58.2.83
In Reply to: RE: That clears up a lot! posted by EBradMeyer on September 21, 2007 at 21:24:25
...there's an immense body of uncontradicted evidence -- just read the hundreds of posts on Prophead and other AA boards -- that CD-Rs made from Redbook CDs sound quite a lot better. That raises the vexing issue, Which is the real CD?
Also, if one reads the literature, it appears that various CD players produce vastly different sounds. Which one is real?
Then we have the Memory Player (or equivalent, if any), which reinterprets the data off a Redbook CD and produces a sonic result (according to all reviewers thus far) superior to any other, even to the CD-R remakes.
So, again, which of those is the CD that "would have sounded the same"?
Even more to the point, which of the above does the aforesaid "bottleneck" sound like? Isn't that worth our knowing?
Had you not yielded to the temptation of "quick and easy comparisons", the above questions might have been addressed.
And then: "I realize you may still believe that the disc itself changes the sound, on the basis of your own unsupported perception." Again, even a casual perusal of these boards, or almost any audio forum, will show that I am hardly alone in my "perception", rather I have been joined by thousands.
"Anecdotal", you say? But what's the plural of "anecdote"? Data!
The rest -- "You always refuse such requests (skepticism is so unbecoming in one's acolytes, isn't it?), so there seems no point in discussing it." -- is beneath you, so I won't touch it except to explain to other readers that no "such requests" have been received at my place.
clark
Proof positive of illiteracy: you've misunderstood even what Uncle Charlie said. He said it's a ripoff.
TL
“…there's an immense body of uncontradicted evidence… that CD-Rs made from Redbook CDs sound quite a lot better. That raises the vexing issue, Which is the real CD?... "Anecdotal", you say? But what's the plural of "anecdote"? Data!”
I you really think thousands of people can’t be wrong, I give you The Church of the Latter Day Saints, the fastest-growing organization on the planet. We’re talking tens of millions here.
So no, the fact that many people seem to hear something doesn’t mean it exists. And if CD players sounded “vastly different” the people writing about those differences in such florid detail would be able to tell one from another without peeking. They can’t.
None of this affects the outcome of our experiment either way, though. What we did was prove that, if high-bit audio sounds better, it isn’t the extra bits that are doing it. It doesn’t matter what particular player we used. I say that’s because it sounds the same as all the others, while you say no, they all sound different. If whatever we used had a characteristic sound, our subjects would have heard it. Over the course of about 550 trials, they didn’t.
As for the Memory Player, whatever that is, if it sounds different from our codec, it’s making a euphonic error, since ours is indistinguishable from the source. You asked what our bottleneck sounds like, and we’ve proven the answer quite well: It sounds like the signal that went into it.
You say you’ve never been asked to test your perceptions, but that’s not true. I asked you to take a blind test to demonstrate that you can hear absolute polarity years ago, but you never responded. So let me propose one again: I’ll make a bit-for-bit copy of a CD – your choice – on a CD-R. I’ll stand in your control room and on the basis of a coin flip I’ll decide which disc to put in the player, ten times. You tell me which disc is playing, ten times. You should get 10/10 with no trouble. Maybe while we’re there I can switch my polarity inverter box in and out of the circuit, and you’ll tell me when it’s active. How about it?
As you may know, I did the polarity test with a local recording engineer who insisted he could hear the effect every time, even through a car radio. His results were random. He then decided that changing the polarity at the preamp level somehow didn’t sound the same as switching the speaker wires. I decided that he couldn't hear the effect as well as he thought. – E. Brad
"If you really think thousands of people can’t be wrong", *I* give you -- the vile Compact Disc. Thousands, millions, *tens* of millions love it!
"The fact that many people seem to" like it "doesn’t mean it" is any damn good!
"And if CD players sounded 'vastly different' the people writing about those differences in such florid detail would be able to tell one from another without peeking. They can’t." You got proof for that assertion? Preferably, DBTs published in a (this time) reputable journal? Put 'em up! Or...
"...while you say no, they all sound different." A common, albeit useful to you, and blatant exaggeration. No one ever has said they "all" sound different. Myself, I simply drew attention to the *fact* that a wide variety of sonic results is available off any given CD depending on the player, and I asked for enlightenment on where the "bottleneck" stood within this range. No reply was forthcoming, save for, "You asked what our bottleneck sounds like, and we’ve proven the answer quite well: It sounds like the signal that went into it." What *that* sounds like, is circular reasoning... or worse, begging the question.
"As for the Memory Player, whatever that is..." I see three monkeys...
"You say you’ve never been asked to test your perceptions, but that’s not true. I asked you to take a blind test to demonstrate that you can hear absolute polarity years ago, but you never responded." Oh geez Luiz, that was *decades* ago. But numerous DBTs (or better) have proven polarity's undeniable audibility -- why don't you believe the DBTs?
You don't have to answer that!
clark
Oh, yeah. I almost forgot:
RCJ: "I simply drew attention to the *fact* that a wide variety of sonic results is available off any given CD depending on the player, and I asked for enlightenment on where the "bottleneck" stood within this range. No reply was forthcoming, save for, "You asked what our bottleneck sounds like, and we’ve proven the answer quite well: It sounds like the signal that went into it." What *that* sounds like, is circular reasoning... or worse, begging the question."
Do you really not get this? The device we were using is a recording system, which passes a signal *through* it. We were testing for whether it made any audible change to the input signal. Except for a broadband hiss at -92 dBA re full scale, it didn't; and it turns out this noise level was below that of virtually all the high-bit recordings we found. This means that on music at normal levels, and on most recordings at any playback level... careful now, this is heretical... it has no sound of its own.
Is it possible that someone out there can spot this device in the signal chain on normal high-bit recordings at normal gain settings? Could be. We tried with a lot of good people on several good systems* for over 500 trials, and didn't find any. That's all. If that's not enough for you, go in peace, or take the test yourself and teach us all how it's done. -- E. Brad
* Lurkers: An equipment list and musical selections should be ready this week; just email me if you want one. It has also been claimed that no Boston-area college offers a recording program; we went to UMass Lowell, where they've built a fine-sounding large listening room with a pair of the best SLS ribbon-tweeter monitors.
That's good to know. Very informative. Now, back to the question: Since the paper inferred results about CD from these experiments, how did said "bottleneck" make things sound compared to the rather wide variety of results available off CD players and DACs? Was it even like a CD at all? Enquiring minds etc.
"Go in peace, or take the test yourself and teach us all how it's done." What is it I detect a note of there? Could it be...??
As I've explained from the start, the objections everyone has to the paper ("a crock" / forum moderator) do not concern the test procedures themselves, particularly, rather 1) the sweeping conclusions drawn from an inadequate rig, and 2) the mysterious nature of the "CD sound" obtained from a still-unspecified apparatus.
clark
[Meyer claims reviewers can't hear CD player differences] "You got proof for that assertion? Preferably, DBTs published in a (this time) reputable journal? Put 'em up! Or..."
It's not up to me to prove reviewers can't hear the huge differences between CD players that they write about; it's up to them to take a blind test, at least once, and prove they can. For all these years, after all this argument, all they do is avoid the issue. Has my statement been proven? Nah. But wine experts comply with these requirements all the time -- it's how they get their street cred. If a subjective reviewer did this even once it would be big news (see below).
"But numerous DBTs (or better) have proven polarity's undeniable audibility -- why don't you believe the DBTs?"
Now you're changing the subject. Sure, there have been tests that prove to everyone's satisfaction that polarity can be audible under certain special circumstances. The signal has to have a fair amount of asymmetry; percussiveness helps; so does a large amount of asymmetrical distortion in the loudspeaker. On most material and systems, most of the time, there was no evidence of audibility. None of those tests prove anything like what you claim in "The Wood Effect", which is (feel free to fine-tune this but I believe it's essentially correct) that you can hear polarity most of the time on just about any material, even through lousy playback equipment, and almost all the time on your personal system. Those claims are entirely different from what's been accepted in the literature, and you would make big news if you could verify them. One positive result -- say, 15/15 or 20/20 correct in a well run test -- and everyone, including me, would credit your remarkable powers. I actually think that would be pretty cool, and I expect you'd enjoy it as well. I notice you didn't accept my invitation, though, and didn't address the stamped-vs-CD-R issue at all. -- EBM
...that they couldn't. Now it's up to *me*, to prove they can? Again, LOL!
"Wine experts comply with these requirements all the time." Very rarely, actually -- only in contests (of which there are few) and in the examination for MW (of whom there are few). Suggest you stick to your own expertise.
Clark: "But numerous DBTs (or better) have proven polarity's undeniable audibility -- why don't you believe the DBTs?"
EBM: "Now you're changing the subject."
Guy, you're the one brought it up! Geez Luiz. You only wanted me to do all over again, what has already been firmly established.
And on it goes:
"The signal has to have a fair amount of asymmetry." Yep. Not like test tones, rather like, oh, musical instruments!
"On most material and systems, most of the time, there was no evidence of audibility." A total mischaracterization! My own tests established a 99% confidence on musical examples alone, and John Atkinson's got IIRC 95%; both were published. And Stan Lipshitz reported 95% as well, on tests involving both tone bursts and music, not to mention that he was a fierce partisan of absolute polarity, as was Prof. Richard Heyser.
"None of those tests prove anything like what you claim in 'The Wood Effect'." I made few claims of my own in that book; it was a compendium of, and analysis of, other people's claims and tests. Interestingly, of the some eighty quotations I found in the literature pre-1988, only one disacknowledged polarity, and he was Sam Burwen, a stalwart BAS member!
"I notice you didn't accept my invitation, though, and didn't address the stamped-vs-CD-R issue at all." The invitation was for an experiment fraught with error, as was the one in the M&M paper, so no, thank you. I wasn't aware that you were also proposing some "stamped-vs-CD-R" sort of thing as well, and upon review I don't seem to see it.
clark
"John Atkinson's got IIRC 95%" :
Reference, please. (Right, there is none.)"Stan Lipshitz reported 95% as well" :
See link for the correct score. "The audibility of polarity on music was not confirmed whether the sound source was vinyl or a 1/4 inch 2-track master tape" says the report, which, if not obvious to you, refers to the 60/113 (53%) result obtained for the part of Lipshitz & co. So there's your "fierce partisan of absolute polarity.""...as was Prof. Richard Heyser" :
Reference, please. (Right, you've always refused to provide one in the past, and you will refuse to provide one now, too.) It's a dubious practice to ascribe claims to people who are no longer with us to deny the assertions.You're full of chicken litter, as usual.
Your own "listening sessions" don't count for the obvious reasons. Amazing that you still keep trying.
As for deluding others, that's a different matter, and so for the record, I have stated on numerous occasions the exact sources *and words* of those three gentlemen, all in print, and I'm not going to repeat myself for nasty twerps.
Do a search.
clark
...and all I've ever found is more instances of you squirming. The only reference you've given that has something to do with the subject matter is the one to your own self-published pamphlet that you keep liberally bringing up. Now that's not a lot, is it, considering your big claims: "Atkinson 95%, Lipshitz 95%, Heyser..."So where are those figures available? Nowhere.
I almost feel bad for you. You've lied so much you can't stop now.
The link gives a nice example of how you go about doing it. (Yes, I know it has that false claim by Atkinson included, thinking as he did that that would somehow help you get off the hook. Nice thought... too bad only his figures were a little bit "misinterpreted" so to speak so it could only make you look that much worse.)
TL
Clark;
Here is my original proposal to you, since you claim not to know about it, quoted from my message to you of last weekend:
"I’ll make a bit-for-bit copy of a CD – your choice – on a CD-R. I’ll stand in your control room and on the basis of a coin flip I’ll decide which disc to put in the player, ten times. You tell me which disc is playing, ten times. You should get 10/10 with no trouble. Maybe while we’re there I can switch my polarity inverter box in and out of the circuit, and you’ll tell me when it’s active. How about it?"
Those experiments might well be fraught with error, as you say, but not because they're invalid or hard to understand. They're too simple and way to risky for you. You claim to have already done the polarity experiment, though you never wrote it up or published any description of it at all that I know of. (If it is in print I'd be very interested to read it.)
So let's see -- you have ignored what I've proposed, ignored or deliberately misconstrued my explanations of what the experiment was about, gone off on irrelevant tangents about nearly everything, ignored my specifications of speakers and room for several of the systems we used, claimed I haven't identified our A/D/A link when I posted it here last week, and generally obfuscated and evaded issues right and left. I think this has been demonstrated adequately to everyone else here, so there's not much point in taking this any further.
-- E. Brad
> > You claim to have already done the polarity experiment, though you never wrote it up or published any description of it at all.
AES Preprint Number 3169, "Proofs of an Absolute Polarity" -- to have been the first of three sets of experiments, the rest abandoned as inconsequential.
> > So let's see -- you have ignored what I've proposed
Hmmm... that does not comport at all well with the above discussion.
> > ignored or deliberately misconstrued my explanations of what the [polarity] experiment was about
I know perfectly well what the experiment was "about" -- inter alia your refusal to mind previous reported experiments.
> > gone off on irrelevant tangents about nearly everything
"Nearly everything." OK... whatever...
> > ignored my specifications of speakers and room for several of the systems we used
I was unaware they had been given here. Nor does anyone else here seem clear on that, given the number of questions raised. Why single me out?
> > claimed I haven't identified our A/D/A link when I posted it here last week
I may have missed link, but to me you wrote, "The device we were using is a recording system, which passes a signal *through* it." Oh. Good to know. Not very specific, though. Elsewhere you wrote, "You asked what our bottleneck sounds like, and we’ve proven the answer quite well: It sounds like the signal that went into it." Equally helpful.
> > and generally obfuscated and evaded issues right and left.
"Right and left." OK... whatever...
Say! So far, you've not replied to repeated questioning on how the "bottleneck's" sonic results compare to an actual CD device, an important consideration as you drew several (abrupt) conclusions about CD -- not about the "bottleneck".
Nor have you replied to my demonstration that you had blatantly mischaracterized my book The Wood Effect.
Nor... nor...
Do those qualify as "right and left"?
> > I think this has been demonstrated adequately to everyone else here, so there's not much point in taking this any further.
"Everyone else here"? The moderator of this forum called the M&M paper "a crock". How d'ya like them apples? Someone else remarked, "They got exactly the results I would expect with the player they used." And: "I believe the authors were being disingenuous when they stated that they used 'very expensive electronics'." And: "Bottom line - The authors got the results they wanted. Neither is a scientist or an engineer and it shows."
Yikes!
Finally, one fellow said, "The player determines the quality of the test." Whereas Meyer said, "It doesn’t matter what particular player we used. I say that’s because it sounds the same as all the others."
I rest my case.
clark
.
...the moderator.
Nor would I advise you to be so sanguine about whom you're aligning yourself with. Don't let your longterm animus against me get the better of your mind. Read this, for a demonstration of who's trying to stick to the point, and who's going overboard:
TSP: Thanks. It's hard not to try, whatever the odds. An eon ago we lived in the same house, and at some well-chosen times, he was a true and good friend. -- E. Brad
I managed to score repeated positive results - 10/10, 19/24, 25/34, 7/8, 26/32, 23/32, etc - with an Etymotic ER-4S driven with a PC sound card, with a rock music sample. There were failed tests too, but even with those included, the overall proportion IIRC does point to a successful test. The effect was far too minor for me to care about for recreational music listening, but it definitely was there, in a realistic listening environment.
Besides the HydrogenAudio link below, also note the flamefest that was the commentary on Critic's Asylum: http://www.audioasylum.com/cgi/m.pl?forum=critics&n=31990
Yeah, by the time you got 10/10 your results were pretty solid, since the chances of that happening randomly are less than 1 in 1000. The advantage of using headphones like those, which seal in the ear canal, is that any very low-frequency stuff in the mix, which might tip you off if it's asymmetrical, will get through.
Did you really do 140 trials with the same source material, or did you use a variety of songs? I hope the latter, unless you enjoy, say, banging on your head with a board (or, as Jerry Lewis once said, "because it feels so good when I stop!"). -- E. Brad
I did everything with "Hamburger Train". Once I found that one sample I was too scared of failure to hunt down any other reproducible sample. I figured that just getting a positive result out of a single popular release was significant enough.
"I did everything with "Hamburger Train". Once I found that one sample I was too scared of failure to hunt down any other reproducible sample. I figured that just getting a positive result out of a single popular release was significant enough."
Aiee! cried Mowgli softly.
You deserve some kind of prize for that; I'm just not sure what it should be.
It's entirely reasonable to do a large number of trials when you discover a source that works for you, of course. That just means you're searching diligently for a way to quantify and establish what you claim to be hearing. We gave our subjects chances to do that when there were few enough in a trial, which was most of the time -- they got to pick the material they thought was best.
But still... after 25 trials, when you've already got good data... it's time to stop, for god's sake. Unless of course you *like* hearing it that many times, which is something I don't care to think about. -- E. Brad
The second test I attempted was at home instead of at work, and it failed miserably (7/16 or something like that). That bugged the hell out of me, so several of the tests following that were simply attempts to isolate the system change that triggered the change in result. That chase alone resulted in an extra five tests.
The chase was not for naught: I couldn't get a good statistical result at all with one pair of headphones, and getting good results for another sound card was a hell of a lot harder. That could be the start of an extremely interesting test: One might be able to correlate the difference in results to some objective THD criteria.
After that, people commented that I shouldn't have run the tests without fixing the number of trials beforehand, because I could have cherry-picked where the test stopped. That alone necessitated redoing the tests at N=32.
It's worth noting that I've done a lot fewer ABX tests since I did that. :)
Axon:
Well, you were following the evidence, like a good experimenter. Of course that way is often tiresome and annoying. If your blind test method gives you the answer after each trial, then there is a possibility that you could affect the overall result by deciding to stop at a certain point, but there's a relatively easy way around that: Decide beforehand how many trials you're going to do, and stick to it. There's a mathematical rescue of a sort if your results are positive too. A score of 10/10 is quite conclusive, and you can stop there.
Yes, you could get 8/10, be disappointed, and choose to go on to try for a better score, which is a bit slippery. But if you miss any at all, you know the effect is at least not obvious. If you do another ten, and again get 7 or 8, you're in that gray area, where effects probably make themselves heard, but not all the time. Remember too that in the case of polarity, asymmetrical distortion in your playback transducer aids audibility, so the device on which you can't hear it may be a better reproducer, not a less revealing one.
Finally, about that hypothetical 8/10 score: The usual confidence level that is asked for is 95%, and 8/10 is 94.5%, so that one is close enough unless you're writing it up for publication. After getting 8/10, I'd also call it fair to do another ten and total them -- but not to do another 10 and throw it out if you do less well. It's pretty easy to grasp what is cheating here and what isn't. -- E. Brad
"..there's an immense body of uncontradicted evidence -- just read the hundreds of posts on Prophead and other AA boards -- that CD-Rs made from Redbook CDs sound quite a lot better. That raises the vexing issue, Which is the real CD?"
LOL. 'hundreds of posts on Prophead and other AA boards' You call *that * an argument? You call that 'uncontradicted evidence'??? (Never read Dennis & Dunn's paper on numerically identical CDS? I'll cut to the chase: no one heard a difference)
Do you being to realize why you folks are considered something of a *joke*?
That's one fine idea of "scientific validation." Another brilliant idea is to have this guy as the spokesperson for the "alternative viewpoint," the "subjectivist camp," or "the new paradigm" or whatever it is that seems so significant about it.TL
The paper is not available to me, but I find the conclusions and the clarifying posts of interest. It seems to me that they have demonstrated that 16/44 is adequate if nothing goes astray. However as you point out, something usually does. I've found that CD's and players interact in unpredictable ways so perhaps a better way to express it would have been that a CD is capable of the same performance.
Reliable people report that higher resolution formats sound better. Now I wonder if part of that is that they may be more forgiving in some manner because they have data to spare. As far as I know, the CD format was originally a compromise of quality vs. recording time. As was the LP. Both good if everything works perfectly. And now we have MP-3...
Rick
Rather, I showed that a wide variety of sounds can be had off a single CD, depending on the player and/or on whether a numerically-exact CD-R copy had been made.
The authors' "bottleneck", lacking any descrip, fails to tell us where it stands, sonically, within the group.
Myself, while I find most Redbook CD reproduction to be edgy and awful, a hi-rez disc of any sort being preferable, I also allow that the Memory Player (Redbook only) produces an elegant, refined, entirely palatable and musical sound.
So: Where among those possibilities does the "bottleneck" stand?
It astonishes me -- or, not -- that the authors' "peers" who reviewed the paper overlooked that vital missing link, the sound of the "bottleneck" and how it would so decidedly affect the outcome. Without such an assessment the paper remains entirely useless.
clark
I think we are referring to the same thing Clark. By going astray I mean that even though they are recovering the data accurately from the disk that the sound quality of CD players is often dependent upon the media characteristics. That has certainly been my experience and is widely recognized (well, by most folks) and there are plenty of mechanisms to account for it.
However since the test didn't use CD players, they have eliminated this as a variable, whether they believed in it or not. If I understand the test correctly they did a 16/44.1 A/D-D/A pass of the demodulated material from sources with higher sample rates and resolutions and compared the result with that analog input.
Since the outcome was that they were indistinguishable this says a lot to me about how good this process CAN be. If their test was accurate, the 16bit,44KS/s linear CODEC process itself is sufficient, at least for one trip.
As far as the sound of the translation outside of sample rate and resolution goes, as pointed out that would show up as an error term in the tests and since it wasn't recognized was apparently not of significance. This isn't too unlikely, especially a single master clock was probably running the whole shebang.
Perhaps the player problems are worse than we thought. Good job that they are obsolete...
Regards, Rick
...that hi-rez is no better than CD.
But they have eliminated CD from the equation!
So how can they know?
All they have proven is, that with an apparently crappy system and unqualified subjects, "hi-rez" sounds no better than an unspecified "bottleneck" -- a "bottleneck" that bears Lord-knows-what relation to actual CD, apart from the fact that it has the right "numbers".
But all CD players have the right numbers!
The reported experiments simply leave us hanging.
clark
I can see that I wasn't missing much.
The "CD standard" is good enough, at least under best-case conditions. No efforts were spent establishing margins however so the results are of no engineering value. I suspect that it is just barely "good enough". Clearly you are correct, they inappropriately infer that on all CD based system that mastering will be the limiting factor.
I do appreciate the work they've done especially since it vindicates some of the tentative conclusions that I'd drawn from experience. However the notion that all CD chains are blameless is absurd. Fortunately now that we have capable computers we can reduce or eliminate many of the medium and playback problems so their conclusions are actually far more applicable now than they were when we were stuck with "real time" CD players.
Thanks for letting me see it,
Rick
x
They do appear to be drawing a wider conclusion than their test data supports. Since I don't have access to the damned (at least in this forum) paper I'm forced to rely upon summaries and postings.
If I can summarize the summaries: 16/44 can be good enough. The test was essentially "best case" so indeed it doesn't say that a CD WILL sound good, especially on a given piece of equipment. Although they seem to think it does.
Since this fits my experience I'm not surprised. Even in my modest systems the quality of the mastering, well actually the whole production cycle, is really the biggest variable. The well made ones sound good. And then there are the other 95%. LP's used to have about the same ratio. Reel to reel tapes did better on average.
Again, I'm coming away with the conclusion that 16/44 is barely adequate. So is a 36 Hp Volkswagen, especially if you enjoy observing the fauna and flora while going uphill.
Rick
I don't know... the window may close... Let me know and I'll work around it.
clark
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