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#201
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Audio challenge (was weakest Link in the Chain)
"Rusty Boudreaux" wrote:
"Bob Marcus" wrote in message ... BTW, the number $4,000 has been thrown around here recently. So far as I know, no one has a fixed list of contributors and amounts, and some people who have offered to contribute in the past may not have been heard from recently. Perhaps, in the interests of truth in advertising, we should say there's a pot in the low-to-mid thousands. If we get an actual taker, we'll probably have to confirm the pool. OK, it's time to get some people to step up to the challenge. We do this every few years - I've been in for $400 from the start. I might as well adjust it for inflation - let's say $500 and the infamous Yamaha AX-700. Oops, I sold that. OK, $500 and a QSC ABX comparitor. That's it... -- Steve Maki |
#202
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Audio challenge (was weakest Link in the Chain)
"Rusty Boudreaux" wrote:
"Bob Marcus" wrote in message ... BTW, the number $4,000 has been thrown around here recently. So far as I know, no one has a fixed list of contributors and amounts, and some people who have offered to contribute in the past may not have been heard from recently. Perhaps, in the interests of truth in advertising, we should say there's a pot in the low-to-mid thousands. If we get an actual taker, we'll probably have to confirm the pool. OK, it's time to get some people to step up to the challenge. We do this every few years - I've been in for $400 from the start. I might as well adjust it for inflation - let's say $500 and the infamous Yamaha AX-700. Oops, I sold that. OK, $500 and a QSC ABX comparitor. That's it... -- Steve Maki |
#203
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Audio challenge (was weakest Link in the Chain)
Rusty Boudreaux wrote:
"Bob Marcus" wrote in message ... BTW, the number $4,000 has been thrown around here recently. So far as I know, no one has a fixed list of contributors and amounts, and some people who have offered to contribute in the past may not have been heard from recently. Perhaps, in the interests of truth in advertising, we should say there's a pot in the low-to-mid thousands. If we get an actual taker, we'll probably have to confirm the pool. OK, it's time to get some people to step up to the challenge. I'll add $5,000 of my own hard cash to the pot for any winner involving cables, amps, CD players, DACs, isolation devices, power cords, etc. The trials must be proctored and verified by someone such as Tom Nousaine. The offer stands indefinitely. I can always be found at: r us t y d ot bou dr ea u xatieeedotorg I committed to $100 before. I will raise it to $200. |
#204
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weakest Link in the Chain
On Thu, 15 Jan 2004 20:05:36 GMT, "Harry Lavo"
wrote: "Stewart Pinkerton" wrote in message ... On 15 Jan 2004 06:20:20 GMT, "Harry Lavo" wrote: "Nousaine" wrote in message ... "Harry Lavo" wrote: May be so, but the considerable increase in transparency between equipment of the early 80's seems mostly attributable to the passive components. Not much else has changed in amplifiers, for example. Utter garbage! Firstly, there has been no improvement in transparency, since the best amps already were sonically transparent, and secondly, what radically changed in amplifiers during the '70s was the active components, as high-speed bipolar power transistors became available. And yet the cumulative effect of improved (from a sound standpoint) capacitors and low-noise resistors has been a marked increase in transparency. Rubbish. Any improvement through the '70s occurred in the treble, and was due to the imroved speed of the power devices allowing dramatic reductions in switching distortion and HF IMD, absolutely nothing at all to do with passives, as metal film resistors and film/foil capacitors were already standard in good quality amplifiers. I have a mid '80s amplifier which sounds exactly the same as a good modern amplifier. You are talking nonsense, there is *no* 'increase in transparency' with modern amps, because amps were pretty much a done deal by the mid '80s. It is also *impossible* for two cables with the same resistance to have any effect on bass. I think if you read my post, I said "early '80's" not "mid-eighties". The early '80's is when most companies switched to using better passives. Utter rubbish. You are once again making it up as you go along, because you refuse to admit your errors. There was of course much *noise* about 'better' passives in the '80s, but as with 'audiophile' cables, there was no *real* difference in performance. This remains true today, with lots of little back-street companies offering magical 'upgrades' to perfectly good audio components. So yes, by the mid-late '80's most amps sounded better. I would have been more prudent to say late '70's. And of course it would be a moot point if you didn't misquote me. Nice dodge, Harry.................. Let me be quite clear. Amplifier design simply *has not* audibly improved since the *early* '80s, or indeed the late '70s, and that has *nothing* to do with passive components, but everything to do with the general availability of much faster bipolar power transistors, which haven't improved significantly since that time. Further, modern resistors are not different in any way from those which were available in the mid-70s (leaving aside the highly specialised bulk-metal resistors which appeared in the early '80s), and neither have film/foil capacitors, indeed top-class film caps are *harder* to find now than they were in the '80s. -- Stewart Pinkerton | Music is Art - Audio is Engineering |
#205
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weakest Link in the Chain
On 15 Jan 2004 22:38:18 GMT, "Harry Lavo" wrote:
"normanstrong" wrote in message ... A 3rd person should be present to verify the cable connection, immediately AFTER the subject has made his guess. This 3rd person should have no contact with the subject during the period of the test. The subject's wife is a good choice for the 3rd person. If you want to cross all the t's and dot all the i's, I recommend a 4th person to proctor the subject. In any case, there should never be a person who knows the actual connection that is within range of the subject. As has been said here so many times, doing dbt's to evaluate equipment at home is a simple process; anyone should do it *whenever* they want to eliminate sighted bias and use the ears only. All you need are four people and a weeks time to do it right. But that's just me, obviously looking for an out! :-) It certainly is, since it can all be done in a couple of hours....... -- Stewart Pinkerton | Music is Art - Audio is Engineering |
#206
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weakest Link in the Chain
On Thu, 15 Jan 2004 23:15:34 GMT, François Yves Le Gal
wrote: On 15 Jan 2004 20:12:11 GMT, (Stewart Pinkerton) wrote: In fact, the technically very best speaker cable that money can buy is made by Dunlavy Audio, and guess what? John Dunlavy himself admits that it sounds just like zipcord. Nope. Quoting John Dunlavy: "I have clearly stated, within many of my posts here on the NET that, within properly operating hi-end audiophile systems, expensive loudspeaker and interconnect cables can seldom make an audible difference or improvement." Seldom never. "However, I do believe it is possible that a properly designed cable might potentially improve the audible accuracy of some high-end audiophile systems." A properly designed cable *might* improve the audible accuracy of a system. http://groups.google.com/groups?selm...s1.newsguy.com At least you did give the full reference for that particular quote, although I note that you failed to highlight this part: "Frankly, however, during blind A-B comparisons between the most expensive loudspeaker cables, 12 AWG ZIP Cord and DAL's Z-6 cable, no audible differences appear to exist within a properly operating, hi-end, audiophile system." So, as ever, you use selected highlights as an argument, when it's clear even from that one article which you quoted, that JD *did* say that his best cable sounds just like zipcord. Typical of you, Frankie, absolutely typical................. -- Stewart Pinkerton | Music is Art - Audio is Engineering |
#207
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weakest Link in the Chain
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#208
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weakest Link in the Chain
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#209
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Audio challenge (was weakest Link in the Chain)
On 16 Jan 2004 06:32:33 GMT, Steve Maki wrote:
"Rusty Boudreaux" wrote: OK, it's time to get some people to step up to the challenge. We do this every few years - I've been in for $400 from the start. I might as well adjust it for inflation - let's say $500 and the infamous Yamaha AX-700. Oops, I sold that. OK, $500 and a QSC ABX comparitor. That's it... OK, I'm in for $500. -- Stewart Pinkerton | Music is Art - Audio is Engineering |
#211
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weakest Link in the Chain
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#212
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Earphones for cable testing?
Some posters have suggested that the movement of a listener's head by as
little as a few inches would alter the sound more than a change of cables. I agree. That being said, why not run the test using earphones? The greater sensitivity of the earphones should make the test more sensitive. -MIKE |
#214
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weakest Link in the Chain
Tom Nousaine wrote:
I'd say your comments are showing that you are working that way. Even IF we allow full credence to your "argument" you still only have mild evidence that DVD-A and SACD may be useful technology. There's nothing in the Oohashi report that has any bearing on the amp/cable issue. Actually, there's nothing in the Oohashi report that has any bearing on SACD or DVD-A either. The reason Oohashi used a proprietary recording/playback system was that commercially available equipment did not produce his supposed "hypersonic effect." Interestingly, in order to replicate Oohashi's findings, you must buy his system. bob __________________________________________________ _______________ High-speed users—be more efficient online with the new MSN Premium Internet Software. http://join.msn.com/?pgmarket=en-us&page=byoa/prem&ST=1 |
#215
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weakest Link in the Chain
"John Corbett" wrote in message
news:BcINb.76887$I06.335211@attbi_s01... In article , "normanstrong" wrote: I'd do 18 trials, instead of 20, since the probability of 14 correct is 4.8%--very close to the statistical requirement of 5%. Actually the p-value for 14/18 is .0154 and the p-value for 13/18 is ...048, so you could ask for at least 13 correct in 18 trials if you wanted a ...05 level test. You are so right! I slipped a column. Forgive me, please. Change that to 13 out of 18. Norm Strong |
#216
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weakest Link in the Chain
"chung" wrote in message
news:AvJNb.64752$5V2.72335@attbi_s53... Harry Lavo wrote: "chung" wrote in message newsqhNb.52763$5V2.65388@attbi_s53... Harry Lavo wrote: Well lets start with timbre, dimensionality, width and depth of soundstage, transparency, microdynamics, macrodynamic freedom, etc etc. And you think these are not caused by frequency responses differences or distortion differences. And seriously, in cables? I think these things can be caused by subtle differences in the passive components used, and in how they and the design itself handle dynamics. Well, you are not making sense here. If there are subtle differences in passive components, they have to show up in frequency response, distortion or noise measurements. All of those you said DBT's are capable of differentiating. Especially if it's fast A/B switching, and not extended, open-ended evaluation. Yes, but not necessarily in the conventional distortion measurements. BTW, active components play a much, much more important role than passives in the resulting sound. Any difference is more likely due to active parts (like poorly designed DAC's) than passive parts. Of course, the modders would like you to think that passives rule... May be so, but the considerable increase in transparency between equipment of the early 80's seems mostly attributable to the passive components. You are simply speculating. Care to provide any evidence to back that up? I would say that the apparent increase of transparency in equipment is due to the prevalent use of CD's as source material. It's much harder to achieve transparency when your phono stages, your cartridge, etc. all contribute signigicant sources of degradations. We probably have even higher level of transparency now that there is more care in the mastering of SACD's, DVD-A's and CD's (such as XRCD). The digital technology exposes weak analog designs (like poor amps with high noise levels) much more than vinyl technology. In any event, metal film resistors and high quality capacitors have been in use since at least the '70's. And in a properly designed amplifier, those components (whether they are carbon resistors or metal film resistors for instance) make very little difference in sound. Not much else has changed in amplifiers, for example. Depends on how you make comparisons. There were poorly designed amplifiers. There are still bad ones now. And yet the cumulative effect of improved (from a sound standpoint) capacitors and low-noise resistors has been a marked increase in transparency. Big OSAF. All you need to prove your point is to provide measurements using so-called high-end passives vs stock passives, and show improvements that are above hearing thresholds. Has anyone done that? I'm not here to prove my point. I'm trying to describe what I have heard as a practicing audiophile of long standing. The big improvement came when the industry moved en masse to using better capacitors and resistors..up until that time the prevailing engineering opinion was they didn't matter. But they did, and do. And buy the way, the effect is not just cd although I don't dispute that eliminating the phono preamp gives greater potential. But the improvement also incuded phono stages. snip Just provide evidence that a measureable difference exceeding JND is not detectible in DBT's, but verifiably detectible in open-ended sighted testing (or any test protocol you care to come up with). If your speculations are true, it should not be too hard to do this, correct? Since there is no technical reason why a cable should affect bass, your concept of "dynamic clamp" is suspicious. That also raises the question of how real are your claims of microdynamics, macrodynamics, dimensionality, etc. Until you can state these in technical terms, I'm afraid that they are not transferrable concepts. This is RAHE, not RAT. I describe; you engineers figure out (by investigating) what explains it. This one is easy. You were not making a careful comparison. Bass response depends a lot on the room acoustics and your listening position, and there is no way a cable could cause a dynamic clamp in bass. Nothing was changed but the cables in a room that I and my partner were intimately familiar with and had the best acoustics I've ever had (both theoretcially and in actual practice). She heard it; I heard it, and two friends heard it. I've never rejected a product as rapidly as that one, that's how bad it was. That is how progress has always come about in this hobby of ours. We make progress if we learn to listen carefully... And if we learn to leave 1% of ourselves open to saying "hmm, that sure doesn't fit what I *think* I know...I wonder....". So you wonder if I changed something else and I tell you no. Now what? Not even going to ask me what cable it was? |
#217
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weakest Link in the Chain
Mkuller wrote:
Research - The program used is tested beforehand to determine the artifact's audibility within it. Audio - Usually music is the program which is a very *insensitive* source. "Bob Marcus" Why would a program be tested beforehand to determine an artifact's audibility, when the point of the research itself is to determine the artifact's reliability? What evidence do you have that music is any less insensitive under any other test that doesn't involve the imagination? Come on, real evidence. Thank you for making my point. If the differences between two amplifiers happen to be a difference in frequency response at 12kHz and the program chosen is sensitive only up to 11kHz you will get...null results. I beleive it was jj who corrected me when I said that DBTs were insensitive - he said the test isn't but music as a program is. Part of the problem with music is that it is dynamic, ever-changing and audible memory is notoriuosly poor at hanging on to differences with a dynamic program. If you're going to lecture us about the scientific method, you ought to try practicing a little of it. It's not enough to claim that a test had some element that you suspect would affect its reliability. You must also offer some evidence that this element actually can affect its reliability. Until you have such evidence, you are talking through your hat. In the meantime, the paradigm for testing audible differences stands. From your questions it's pretty obvious that you don't have an real experience or knowledge in applying DBTs scientifically. I've explained where I see some important differences in their application between research and audio and all you can do is turn the question around and ask me for proof. I'm looking for proof that DBTs actually work in comparing audio components with music and don't obscure the subtle audible differences. From my experience and scientific knowledge it appears to me that they don't. I have told you that I believe they do this because of the way the brain works in storing and recalling audible memory. Relaxed listening uses a different part of the brain than the matching/decision-making required in ABX. So far the only differences DBTs seem to reveal in audio component testing are big ones - gross frequency response and loudness (i.e. as in speakers or bright CD players). If you have proof or evidence that DBTs actually work for the use you are suggesting, please provide it to me. If not, you are welcome to your belief system and I'll stick to mine. Regards, Mike |
#218
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weakest Link in the Chain
Harry Lavo wrote:
And if we learn to leave 1% of ourselves open to saying "hmm, that sure doesn't fit what I *think* I know...I wonder....". So you wonder if I changed something else and I tell you no. Now what? Not even going to ask me what cable it was? Not necessary, since that would be like sighted testing at this point. Go back and re-run your test first. Then report here if you truly believe that your have repeatable, verifiable results (bass clamping, i.e.). We can get hold of that cable to make some measurements. That's how we can improve our understanding of things. Knowing the identity of the cable adds nothing at this time, and can only smear the reputation of that cable if you made an errant observation. |
#219
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weakest Link in the Chain
On 16 Jan 2004 16:16:58 GMT, (Stewart Pinkerton) wrote:
At least you did give the full reference for that particular quote, I always give full references, Mr. Pinkerton. although I note that you failed to highlight this part: "Frankly, however, during blind A-B comparisons between the most expensive loudspeaker cables, 12 AWG ZIP Cord and DAL's Z-6 cable, no audible differences appear to exist within a properly operating, hi-end, audiophile system." Here's the full post: SNIP "Subject: Dunlavy at the 2001 Electronics Show From: (John Dunlavy) Date: 12/20/00 2:00 PM Mountain Standard Time Post of 12/20.00 from In his above referenced post, commenting on a recent post from Howard Ferstler, Harold Nash wrote: From the above, are we to assume that you are saying that Dunlavy does not have any integrity and does not have the courage of his convictions? How do you otherwise condone his compromise? How about if he also advertised that he will use Shakti stones on his gear and paint all his CES show CDs purple? Would you then defend what appears to be hypocrisy on Dunlayvs part by saying what you said above? I guess you mean that business is business, caveat emptor, never give a sucker an even break. etc. From your record of postings here and elsewhere which are repleet with diatribes about snake oil and sleezy high end salespeople it is shocking to see you write what you just did. If you condone Dunalvy using 'snake-oil' to sell gear and attract customers then you cannot condem anyone else for that. I used to admire your courage Howard but I now wonder of you lack the courage of your own loudly repeated conviction as it seems that Dunalvy does. This is a black day for the Rationalists who beleived in you. Well, how does one answer such a post as this? I have clearly stated, within many of my posts here on the NET that, within properly operating hi-end audiophile systems, expensive loudspeaker and interconnect cables can seldom make an audible difference or improvement. So - why did I design and why does DAL sell cables that might not make any improvement in the audible accuracy of a system? The answer is relatively simple and should be easily understood by most readers. As an engineer with appropriate technical/professional credentials, I believe in designing products that first conform to the teachings of competent engineering and physics - and whose relevant electrical/audible properties can be confirmed by accurate, lab quality measurements. (Such professional E.E. credentials are typically missing among those who design audiophile cables for many large audiophile cable companies.) Most of the expensive, "high-tech appearing" audiophile loudspeaker cables do not conform to this criteria. They are sold largely on the basis of a "hi-tech appearance" rather than "real world design and performance criteria". Recognizing this, I was curious (as an engineer) whether audiophiles would accept and approeciate cables designed according to good engineering criteria. Frankly, however, during blind A-B comparisons between the most expensive loudspeaker cables, 12 AWG ZIP Cord and DAL's Z-6 cable, no audible differences appear to exist within a properly operating, hi-end, audiophile system. But my "reasoning" asks the question: why not manufacture and sell cables whose properties conform to proper design criteria - rather than mere "appearance" and a "high ticket" price tag? However, I do believe it is possible that a properly designed cable might potentially improve the audible accuracy of some high-end audiophile systems. But it is far less likely that an expensive but "poorly designed" cable could achieve the same result. Much the same can be said for expensive interconnect cables with a hi-tech appearance but which seldom possess optimum electrical properties required for bes audiophile system performance. The three most important electrical properties of interconnect cables a 1) good shielding, 2) low capacitance and 3) low micphonics. I designed DAL interconnect cables with the intent of achieving these three most important properties. I sincerely hope the above info explains my position regarding hi-end audiophile loudspeaker and interconnect cables. John D." Note that John Dunlavy has added "However, I do believe it is possible that a properly designed cable might potentially improve the audible accuracy of some high-end audiophile systems" after reporting a single listening test (in unkown conditions), so my quotes were perfectly relevant. So, as ever, you use selected highlights as an argument, when it's clear even from that one article which you quoted, that JD *did* say that his best cable sounds just like zipcord. Typical of you, Frankie, absolutely typical................. I thought that drivel and ad hominem attacks were forbidden here, Mr. Pinkerton. Thank you for proving me wrong in that respect. And it's Mr. Le Gal to you, Mr. Pinkerton, not "Frankie". |
#220
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weakest Link in the Chain
(Mkuller) wrote:
With sighted listening, you have the *possibility* of bias interfering and giving false positive results. With DBTs you have the *certainty* of the test interfering with subtle audible details and providing false negatives, since most all DBTs give null results. It would appear sighted listening (under some circumstances) is actually superior. (Stewart Pinkerton) wrote: As ever, lots of handwaving and protestations from Kuller, with absolutely *no* support. In actual *fact*, with sighted listening you have the *certainty* of bias casusing false positive results, as you can easily prove by *not* changing anything in such a test, while all Mike means by DBTs 'interfering with subtle details', is that the results don't match his sighted expectations. Basically, all of physics, neurophysiology, electrical engineering, and controlled listening tests tells us that 'wire is wire', but this *must* be wrong, because Mike likes expensive cables. Hmmm...... Sorry but *physics, neurophysiologygy and EE* don't tell us that, you do. And without any proof to back it up. Extraordinary claims require extraordinary *proof*, Mike, not mere handwaving.................. Yes, and that goes for your claims as well. I have never heard two different amplifiers that sound the same - your claim that they do is pretty extraordinary. Your only *evidence* is DBTs used in a flawed way that obscures the audible differences. Yet you are unable to provide any verification the the test actually *works* in the way you are advocating it. Extraordinary claims... Regards, Mike |
#221
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Earphones for cable testing?
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#222
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weakest Link in the Chain
"Nousaine" wrote in message
news:fuJNb.64736$5V2.72379@attbi_s53... "Harry Lavo" wrote: "Nousaine" wrote in message news:fBkNb.68743$na.39732@attbi_s04... (Audio Guy) wrote: n article gi4Nb.55157$8H.104911@attbi_s03, "Harry Lavo" writes: ..snips to specific content..... Thank you for remembering. However, you don't quite remember accurately. The control test I proposed is similar to the Oohashi et al test in that it is evaluative over a range of qualitative factors, done in a relaxed state and environment, and with repeated hearing of full musical excerpts. But it is not a duplicate of the test. The arguments for such tests have been made here for years..long before the Oohashi article was published. Let's remember that the Oohashi "article" was not "published" in a peer-reviewed journal but exists as an AES Convention Preprint like my AES Preprints. Therefore they carry exactly the same weight as anything I've presented at a Convention, AES Chapter Presentation or in a consumer audio magazine. Tom the Oohashi article I introduced here was peer reviewed and appeared in Journal of Neurophysiology. OK; point taken. I wonder why this hasn't appeared in the JAES? It was discussed extensively and I repeated the link often. Here is the link once again.: http://jn.physiology.org/cgi/content/full/83/6/3548 I find it troubling that you, who makes a living as a "testing expert", would have ignored such an important discussion, regardless of what you may have thought of it. Else you would know it was a peer-reviewed and well documented piece of research. Actually a similar piece was presented in 1991 at an AES Convention but was not selected for publication. But what have I "ignored?" That ultrasonic stimulus can influence body functions? If you read the paper carefully you'll see that certain bias may have been implemented (the "random" selection of presentation order was exactly repeated in reverse instead of re-randomization) but even so the data shows that in their subjective analysis that subjects weren't able to show a "liking" for one vs the other. It is true that they seemed to see one as softer, more reverberant but the "like vs dislike" factor was not significant. Yes but they alternated "a" and "b" to get rid of any order bias. However, I must admit I am not sure why the did the fixed sequence, as Bob Marcus and I discussed here some time back, it was probably in order to allow them to listen once without evaluating, and then to do the written evaluation on the "second" listen. We both wish more detail had been in the article on this. However, so long as the alternated the order of "a" and "b" there is no experimental order bias. So what? That most likely means that there was no significantly important sound quality difference. There were statistically significant differences at the 95% confidence level on several factors, and these correlated with the physiological differences registerd in the brain, as measured in other segments of the tests. The mechanisms obviously are not known, as they admitted. But again .... so what? You seem to be just hunting for evidence that supports your pre-held ideas. There's nothing wrong with that per se but you have not, so far, done anything but propose an hypothesis that you, nor anyone else has ever, tested. No, as I stated from the start the Oohashi experiment is of great interest for two reasons: 1) because it departs from the conventional wisdom and if correct has far-reaching implications. Thus I would hope it would cause a) a little less certainty about the conventional wisdom, and b) an effort to either confirm or deny the findings. 2) the test itself was carefully constructed to create a relaxed environment for the musical evaluations, and the piece was played to conclusion each time, giving enough time for the emotional part of the listening experience to kick in. And the test was evaluative, rather than comparaive in nature. Technically it was proto-monadic, meaning the test "cells" were evaluated separately, but with knowledge of the other "cell" when doing so. Be MY Guest. I'll be more than happy to supply consultation without charge and assist in any reasonable manner. Well given my age and current financial resources, I would have to make it my remaining life's work.... But if anybody out there wants to do such a test and has the resources to pursue an adequate dbt ab or abx vs. evaluative dbt protomondaic vs. sighted evaluative protomonadic, I too would be happy to assist in design and implementation. He and his researchers apparently reached the same conclusion...that it was a more effective way of testing for the purposes under study...which were semi-open-ended evaluations of the musical reproduction. Double blind, by the way, as was my proposed test. As long as it's double blind I have no problems with it, but I have yet to see you propose any reason for rejecting the current DBTs except that they don't agree with your sighted results. . That's because you continually ignore the arguments of myself and other "subjectivists" here on RAHE and elsewhere. The reasons have been well documented. You'll find my reiteration of them elsewhere in this thread. This is just not true. Personally I've listened to and incorporated those arguments into controlled listening environments time and again. The single largest problem I've encountered is actually getting a 'proponent' into a controlled testing environment. Indeed one of my experiments (documented in Stereo Review in 1998 "To Tweak or Not to Tweak") was conducted because an on-line proponent argued that 'series tweaks' were needed to uncover audible differences (one wire by itself may not reveal differences but a series of tweaks would.) That particular proponent agreed to a test, to be held in his system, where I would place a single 'bad' wire in his system and he would only have to tell me if that wire were "in" the system with the I/O terminals covered with a blanket. As you might suspect that subject "disappeared" two weeks before that experiment (to be held at my own personal expense) was to be held. So, I did it myself by assembling a system with vacumn tube preamp,RCL power amp, special interconnects and speaker cables, an outboard DAC, special vibration control devices and wire/cable dress and comparing that to a system with a 20 year old $99 kit preamp, a 10 year old integrated amplier, junk box rcas and 16 ga car-audio zip cord speaker cables with non-PC dress (6-feet for one channel and 25-feet for the other with the longer section wrapped around the AC cables.) I was trying to find as large a 'tweak' system difference as I could muster with the idea of dis-sembling the system to which 'tweaks' mattered. I was surprised that I couldn't distinguish either system driving the PSB Stratus Mini PSACS reference speakers (with frequency response curves taken in the NRC anechoic chamber) using an ABX Comparitor. Well I appreciate that you did respond to his discussion, although I am not a "tweaker" and think it was a rather vulnerable place to start. Interestingly not one of 10 hard-core audiophiles was able to reliably distinguish one system from the other either in 10-16 trial single listener, sweet spot sessions with no time limits and NO switching devices. They all brought their own prefered cds for evaluation. Good for you. Testing other people was an obvious next step. But after getting those results, it never entered your mind that it could be the test technique itself at fault (as it relates to the ear/brain processing)? Seems to me that's where the "belief system" kicks in, so as not to even think about the technique itself being a potential issue. Again you are joining Stewart in repeating an (at best) half-truth ad nauseum here. Those firms use DBT's for specific purposes to listen for specific things that they "train" their listeners to hear. That is called "development". Sure and ..... what else is there to hear but "real acoustical" differences? Some of the blind tests I've conducted were testing the ability of self-trained listeners to identify 'differences' that had been described as "pretty amazing" by the subject using the very reference system and the programs that he had claimed illustrated these differences clearly. One in particular used as long as 5 weeks in-situ training using the actual test apparatus and others have used the reference system of the claimants. You have cited that test before, but without details as to how the final choices were made (eg what happens after the weeks of listening, it continues to be an "antedotal outlier" in your work. What's the question? Well, for example, was it comparative, evaluative, or an identification test. And was that done throughout each "trial" or was it done at the end. If at the end, then there is still the stress of "choice". How was the blinding handled, who else was present, etc. In the food industry we used such tests for color, for texture and "mouth feel", for saltiness and other flavor characteristics. That is a far cry from a final, open-ended evaluation whereby when you start you have simply a new component and are not sure what you are looking for / simply listening and trying to determine if / how the new component sounds vs. the old. It is called "open ended" testing for a reason... Sure but one can do such a test without sound and still get usable results for marketing purposes. I'm not interested in how the sound "feels in the mouth" unless that feel is soley related to sound quality. If we wish to limit the assessment to sound alone then bias-mechanisms are needed AND closely spaced presentations are the most sensitive. The above is simply jibberish. :-) What matters to me is SOUND QUALITY and not "mouth feel." I was giving you a metaphor example. "mouth feel" is a specific of food evaluation, just as "brightness" is a specific of sound reproduction evaluation. Or "grain" or "bass cleanness" or "two-dimensionality", etc. In other words, if you know what you are looking for you can easily use a comparative dbt ab test to determine relative presence or absence or liking vs. disliking. That's why we used this type of testing in development. But it was not as useful in obtaining overall acceptance / desireability of the product, where monadic or proto-monadic testing turned out to be more reliable/meaningful. Yes, because it never ends, and so never gets to a result. This is just retoric and is absolute nonesense! :-( How so, if it is open-ended it seems by definition to not have an end. How do you tell when it has reached the end, when it gets the results you want? To move off-topic for a moment I will say that most open sound quality evaluations I've seen tend to do exactly that. Generally the 'evaluation' starts with a presentation (salesman, conventioneer, audiophile, etc) after which the presenter asks "whaddya think?" This is followed by some discussion in which only a few present engage. Often they will report different "things." Then the presenter will say "Let's try again with BETTER material" and the process will continue, often with considerable 'negotiation' of differences, until there is a trial where the 'right' answers are given and then the session is over. Sometimes there will be continued program delivery and some hand-waving and back-slapping. But, I've seen the script played time and again. We are talking about how audiophiles do comparisons in their own homes, not with salesmen in a convention or showroom. Talk about straw men! I'd say you were adressing Stawmen. I was describing how how I've seen sound quality assessments being made. Of course, I'm also, perhaps unfairly, extrapolating them to single listener-home decisions but, quite frankly, I'm used to hearing enthusiasts defend purchase decisions based on "reviews." I'm talking about audiophiles who prefer open-ended, sighted or blind evaluations in their own home systems to make component choices. Your statement above about salesmen is a complete non-sequitor. could reason to believe that conventional dbt or abx testing is not the best way to do it and may mask certain important factors that may be more apparent in more relaxed listening. There's been no evidence that this is true, other than the non-published Oohashi test. There has never been a test run with a control test that would show this. That is the crux of the matter. Ball in your court. Be glad to helpin any reasonable way. Well, your profession depends on you being credible. Don't you think a definitive test in your current techniques favor would swing the remaining "doubters" into your corner. Wouldn't you like to be the person who finally lays the dbt "fears" to rest? After all, you *are* one of the biggest proponents of the test, and yet you have yet to do any real verification of its worth for purposes of open-ended evaluation. You continually accept null results as meaning that no differences exist (which is unscientifc) rather than confirming that the test itself isn't biased in this direction. Not that this isn't an interesting theorem. But, there's no replicated evidence to support it. On the other hand, ABX and other blind testing has quite an interesting set of data on testing audible quotient of products that fit within the known limits of human acoustical thresholds. Okay, what is the "known limit" of soundstage depth, tom? Perceptible in listening bias controlled conditions. Or any other conditions with elements known to exceed human threshold acoustical limits. "Phantoms" work for me as along as they are replicable. I'm reasonably astute, but I am having trouble understanding what you are saying here, Tom. Can you further explain, please. Mr Lavo seems to be arguing that some kind of 'test' that requires lengthy evaluation under "open-ended" conditions would somehow be more suitable for the average enthusiast. My guess is that no one except a few who may own a store would have such an opportunity and that a week-end or overnight ABX test (perhaps with the QSC $600 ABX Comparitor) or other bias controlled test is not only more practical but quite implementable for the truly curious. Well, son, let's see if you have a fever. I'm sorry but I just broke my last thermomenter. We'll just use this barometric probe instead...it should tell us the same thing. It is used to measure weather every day, and weather includes temperature, doesn't it? :-) I'll accept the emoticon. I expect you'll do the same for me. I always have. That's what they're for. And again, your only defense is that DBT results don't agree with your opinions. DBTs can and have been done over long periods with relaxed listening, and the results are the same. On Tom's say so and without any detailed description or published data. Actually that has been published in Audio and The $ensible Sound. You may can also trace data to the SMWTMS site through www.pcabx.com No monadic or proto-mondadic evaluative tests have ever been done as a control. without them you have *no* proof...simply assertion. And that's doubly the case Harry with your comments as well. You seem to expect that your extrapolations from an unreplicated ultrasonic frequency study somehow also has application to the wire/amp debate. Simply assertion .... no real appicable data. The Oohashi et al test has nothing to do with it other than to serve as an interesting example. I was arguing for proto-monadic open-ended home evaluation here long before I stumbled across the Oohashi article. I'm not sure I used those words but that was what I was arguing in favor of. I'm talking about a rigorous, scientific test of dbt, control proto-mondadic, and sighted open ended testing. With careful sample selection, proctoring, statistical analysis, and peer-reviewed publication. Once that is done I will be happy to accept what conclusions emerge. It hasn't been done, and so *assertiosn* that comparative dbt's such as abx are appropriate is just that, an assertion. As is your hypothesis. But bias-controlled listening tests of any kind, no matter how un-intrusive, have never shown that wire/amp sound has any basis in acoustical reality. When are you going to show us some data and stop "arguing?" When a proper control test has been done, as I have stated. And if you don't like my suggestion for a control test, propose one of your own that aims to bridge the gap between sighted evaluative listening and conventional dbt comparative tests. As is hte hypothesis that this test will have some useful benefit. And I think this poster is right; this test would be rejected if it failed to support that theory. Well, I'll give you the same reply I gave him. You are assuming it would give the same results. suppose it showed that proto-monadic testing actually supported sighted evaluative listening tests. you don't think it would be reported. Your assumption shows that you are operating from a belief system, not as a proponent of truly scientific testing. I'd say your comments are showing that you are working that way. Even IF we allow full credence to your "argument" you still only have mild evidence that DVD-A and SACD may be useful technology. There's nothing in the Oohashi report that has any bearing on the amp/cable issue. Nor am I saying there is. Nor am I talking specifically about DVD-A and SACD. My only reference to Oohashi was to the type of evaluative test set up they used to do their research, which seem to be along the lines many audiophiles on this forum have argued in favor of. It's much more than an assertion, it has data to back it up, unlike your assertions that audio DBTs are just "assertions". The issue isn't so much the blind vs sighted as it is the comparative vs. the evaluative....and while a double blind evaluative test (such as the proto-monadic "control test" I outlined) may be the ideal, it is so difficult to do that it is simply not practical for home listeners treating it as a hobby to undertake. So as audiophiles not convinced of the validity of convention dbt's for open-ended evaluation, we turn to the process of more open ended evaluative testing as a better bet despite possible sighted bias. Better bet? As opposed to any other process that reduces the likelihood of false positives? Yep. IOW he's willing to accept the increased (actually the nearly universal) probablity of false positives as being less important than limiting the results to sound quality alone. Yes, with the distinct possiblity that the "sound quality only" test is actually missing/masking some key evaluative areas. How could it "miss/mask" key sound quality areas by eliminating non-sonic influences? If you're suggesting that non-sonic variables are important ...... wjho would argue with that? What is this whole discussion about, Tom? If you are suggesting that factors other than sound quality are more important to YOU, I have no trouble with that. Indeed because I've listened to so many amplifiers under listening bias controlled conditions and found that nominally competent ones are sonically equivalent I no longer consider "sound quality" as the most important purchase consideration. So what? Why should anyone else care? I am suggesting that for evaluative purposes for chosing home audio gear (even if one wants to choose primarily based on sound) that using comparative quick-switch ab or abx testing *may* be throwing at least a few parts of the baby out with the bath-water. Until proven otherwise. Sounds like he's a marketeer, doesn't it Since you obviously share the opinion that marketers are dishonest, I'd suggest you try a little test. Who said or implied dishonesty? A marketers job is to market products as far as I can tell. No dishonesty infered or implied as a class. You "said" that factors other than sonics may be important to consumers. I'd fully agree with that ..... but I wouldn't argue that experiments that use listener bias controls are somehow "missing" or "masking" important sound quality issues. Well, that's the whole issue of how the testing / evaluation is done now, isn't it? I'll blindfold you and put you in a roomful of people. Ask any and all of them questions that show honesty or dishonesty, and then tell me whom the marketers are. See if you can pick them blind, eh? Tell you what; put me in a room with Floyd Toole, Dave Clark, You, Bill Clephane, Woody Cade, Bob Harley, John Atkinson, Roger Cox, Jerry Novetsky, and a few others, and then disguise their voices with Lexicon effects and with audio topics I'll be able to tell the bull-throwers from the others. I never claimed to be an engineer, allthough my father was (and wishes I had been). I did happen to live across the street from Ken Moore, then head of CBS labs back in the early '70's and had many an interesting discussion with him over drinks about engineering and audiophilia. Suffice it to say, his AR receiver and AR-4's didn't cut it with me, nor my preoccupation with extended frequency response and accurate phase response with him. But I learned a lot, and had a good time. Please do not infer that I think marketers are dishonest. But I do not think for a minute that a good one would not use every tool in the basket to sell product. If that were my job (and it isn't) I'd use all those tools. Perhaps that's why I'm not in marketing. Thank you, that sets you apart from Stewart. You are right up to a point. But a *GOOD* marketer (both in the effects achieved and in ethical standards) differentiates between choosing the best way of presenting the truth about a product, and promoting a lie. |
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"chung" wrote in message
... Harry Lavo wrote: And if we learn to leave 1% of ourselves open to saying "hmm, that sure doesn't fit what I *think* I know...I wonder....". So you wonder if I changed something else and I tell you no. Now what? Not even going to ask me what cable it was? Not necessary, since that would be like sighted testing at this point. Go back and re-run your test first. Then report here if you truly believe that your have repeatable, verifiable results (bass clamping, i.e.). We can get hold of that cable to make some measurements. That's how we can improve our understanding of things. Knowing the identity of the cable adds nothing at this time, and can only smear the reputation of that cable if you made an errant observation. Well, the cable is long since gone, so I can't do that. It was about nine years ago anyway. I don't believe it is even in that manufacturers line any longer (which may mean mine wasn't the only negative reaction). All I will say is that it was from a well known and reputable manufacturer. I thought perhaps you had some idea of what the "bad" cables were by name. |
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On Fri, 16 Jan 2004 20:38:47 GMT, "Harry Lavo"
wrote: There were statistically significant differences at the 95% confidence level on several factors, and these correlated with the physiological differences registerd in the brain, as measured in other segments of the tests. The mechanisms obviously are not known, as they admitted. And those differences were recorded at very strange and unlikely locations in the brainstem. Kal |
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Mkuller wrote:
Mkuller wrote: Research - The program used is tested beforehand to determine the artifact's audibility within it. Audio - Usually music is the program which is a very *insensitive* source. "Bob Marcus" Why would a program be tested beforehand to determine an artifact's audibility, when the point of the research itself is to determine the artifact's reliability? What evidence do you have that music is any less insensitive under any other test that doesn't involve the imagination? Come on, real evidence. Thank you for making my point. How did I make your point? Oh, wait, I see--I did so by writing something you could completely misconstrue... If the differences between two amplifiers happen to be a difference in frequency response at 12kHz and the program chosen is sensitive only up to 11kHz you will get...null results. As you would in any comparison. The artifact is in the sound, Mike, not in the equipment. If the artifact is at 12kHz and the program has no signal above 11kHz (I have no idea how a program could be "sensitive"), then the artifact doesn't exist in that program. The reason DBT subjects will "miss" it is because it isn't there. That's the advantage of DBTs over sighted listening--they miss the artifacts that aren't there. Sighted listeners hear the artifacts that aren't there. I beleive it was jj who corrected me when I said that DBTs were insensitive - he said the test isn't but music as a program is. Part of the problem with music is that it is dynamic, ever-changing and audible memory is notoriuosly poor at hanging on to differences with a dynamic program. Which is true whenever and however you compare audio components. That's what JJ said to you. If you're going to lecture us about the scientific method, you ought to try practicing a little of it. It's not enough to claim that a test had some element that you suspect would affect its reliability. You must also offer some evidence that this element actually can affect its reliability. Until you have such evidence, you are talking through your hat. In the meantime, the paradigm for testing audible differences stands. From your questions it's pretty obvious that you don't have an real experience or knowledge in applying DBTs scientifically. I've explained where I see some important differences in their application between research and audio and all you can do is turn the question around and ask me for proof. Please quote me correctly. I didn't ask for proof. I asked for evidence. Evidence that these are indeed important differences, that they produce less reliable results. If you want to challenge settled science, that's what you have to do, Mike. And you can't. I'm looking for proof that DBTs actually work in comparing audio components with music and don't obscure the subtle audible differences. From my experience and scientific knowledge it appears to me that they don't. Then your scientific knowledge is woefully inadequate. I can't help that. I have told you that I believe they do this because of the way the brain works in storing and recalling audible memory. Relaxed listening uses a different part of the brain than the matching/decision-making required in ABX. So far the only differences DBTs seem to reveal in audio component testing are big ones - gross frequency response and loudness (i.e. as in speakers or bright CD players). If you have proof or evidence that DBTs actually work for the use you are suggesting, please provide it to me. If not, you are welcome to your belief system and I'll stick to mine. The difference between your belief system and mine is that my beliefs conform to accepted scientific findings in the fields of physics, electronics, and psychoacoustics. Yours do not. bob __________________________________________________ _______________ Get a FREE online virus check for your PC here, from McAfee. http://clinic.mcafee.com/clinic/ibuy...n.asp?cid=3963 |
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"Kalman Rubinson" wrote in message
news:WuYNb.81412$xy6.137942@attbi_s02... On Fri, 16 Jan 2004 20:38:47 GMT, "Harry Lavo" wrote: There were statistically significant differences at the 95% confidence level on several factors, and these correlated with the physiological differences registerd in the brain, as measured in other segments of the tests. The mechanisms obviously are not known, as they admitted. And those differences were recorded at very strange and unlikely locations in the brainstem. Kal, I am not a brain expert by any means but I believe they were in areas normally associated with emotional response (specifically "pleasure response") based on other work done in this area. If I am wrong, please expand and explain. Harry |
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Nick Georges wrote in message news:9aiKb.65416$I07.286195@attbi_s53...
Ok...I'll bite. IMO, the #1 component is defiantly the room. I've got great speakers...and they sound like crap because of my room. I will quote from something else I read recently; "a great room can make a marginal system sound magical, and a bad room can make a great system sound horrendous". Not verbatim, but you get the idea..and it is true as I've lived both ends of this spectrum in the past year. in my last house, I ran a system I put together for $1200. It was the cats ass. Completely pleasing and then some. In my current house, I built a system costing 5x this...and it is nothing but frustration. Again, the room is putting all of my upgraded components and speakers to waste. My other rule of thumb is "crap in, crap out"...so source and material are high on that list. I'd go: 1. room 2. speakers 3. source/material 4. amp and I'd leave it there as a premap is just not even necessary in a purely digital domain...which is where I live. If you are listening to LPs and tapes, then i'm sure it has a place on the list. In my opinion, the way to budget a system: 1. Speakers (1. mains 2. sub 3. center 4. surrounds) 2. Player 3. Receiver 4. Speaker cables 5. RCA/Interconnects Sincerely |
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On Fri, 16 Jan 2004 21:45:29 GMT, "Harry Lavo"
wrote: Kal, I am not a brain expert by any means but I believe they were in areas normally associated with emotional response (specifically "pleasure response") based on other work done in this area. If I am wrong, please expand and explain. I have not read the article in a while; since it came out, in fact. However, I do recall that they tried to make such a case but the areas were related to other sensory systems, iirc. I remember being puzzled about why the researchers (and the reviewers) weren't equally puzzled. If I have the time, I'll go back and look for the specifics. Kal |
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Harry Lavo wrote:
"chung" wrote in message ... Harry Lavo wrote: And if we learn to leave 1% of ourselves open to saying "hmm, that sure doesn't fit what I *think* I know...I wonder....". So you wonder if I changed something else and I tell you no. Now what? Not even going to ask me what cable it was? Not necessary, since that would be like sighted testing at this point. Go back and re-run your test first. Then report here if you truly believe that your have repeatable, verifiable results (bass clamping, i.e.). We can get hold of that cable to make some measurements. That's how we can improve our understanding of things. Knowing the identity of the cable adds nothing at this time, and can only smear the reputation of that cable if you made an errant observation. Well, the cable is long since gone, so I can't do that. It was about nine years ago anyway. I don't believe it is even in that manufacturers line any longer (which may mean mine wasn't the only negative reaction). All I will say is that it was from a well known and reputable manufacturer. I thought perhaps you had some idea of what the "bad" cables were by name. I don't believe any cable can cause bass clamping. It will take an extraordinary effort to design a cable that affects the bass response. Therefore I believe your comparison test was either at fault, or your definition of "bass clamping" means something other than I thought. You can change the volume slightly, and perceive a substantial change in bass. That's why something like an ABX comparator, and quick switching, short snippet testing, can be very useful. |
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Mkuller wrote:
I have told you that I believe they do this because of the way the brain works in storing and recalling audible memory. Relaxed listening uses a different part of the brain than the matching/decision-making required in ABX. So far the only differences DBTs seem to reveal in audio component testing are big ones - gross frequency response and loudness (i.e. as in speakers or bright CD players). If you have proof or evidence that DBTs actually work for the use you are suggesting, please provide it to me. If not, you are welcome to your belief system and I'll stick to mine. "Bob Marcus" The difference between your belief system and mine is that my beliefs conform to accepted scientific findings in the fields of physics, electronics, and psychoacoustics. Yours do not. So you say, once again. It always comes down to this. The difference is that you believe in yours and I in mine - that's the only difference. You still have not provided me any verification test or proof that DBTs work in open-ended audio equipment comparisons using music and do not obscure subtle detail. Claiming that you have *science* on your side is not enough, since science relys on proof, not assertions. Regards, Mike |
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François Yves Le Gal wrote:
Well, how does one answer such a post as this? *snip* The easiest way it to bypass all of this and backtrack the metal itself. Nobody makes their own copper. This is done at a smelting plant/foundry. Big machinery with huge hundred million dollar plus investments and hot, dangerous equipment. The slag pot trucks alone are so heavy that they could run over your car and literally not feel the bump. The slag pits themselves are monitored and controlled like coat plant ash piles - they are considered toxic material and regulated as such. No sane company would re-smelt the copper as refining it further would require better equipment and higher temperatures than the original stuff. It never happens. The copper comes from the plant in 99.99 or 99.999%(OFC) pure slabs that weigh several tons and are extruded after being shipped to the company into wire or copper pots or whatever they desire. There are maybe a few dozen such plants in the entire world - and that's IT for copper production. Everyone uses the same copper, made to the same stnadards, so whatever you see that's made of copper, unless it's an alloy, is exactly the same stuff. The same holds true for gold - it is made 99.99x% pure ingots and then shipped to the various companies to be used for whatever they desire - plating for connectors or jewelery or alloys or whatnot. Wire really IS wire, because it comes from the same place. Only the manner in which it is made into wire/configuration and size/shape make any differnece. |
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Harry Lavo wrote:
"chung" wrote in message ... Harry Lavo wrote: And if we learn to leave 1% of ourselves open to saying "hmm, that sure doesn't fit what I *think* I know...I wonder....". So you wonder if I changed something else and I tell you no. Now what? Not even going to ask me what cable it was? Not necessary, since that would be like sighted testing at this point. Go back and re-run your test first. Then report here if you truly believe that your have repeatable, verifiable results (bass clamping, i.e.). We can get hold of that cable to make some measurements. That's how we can improve our understanding of things. Knowing the identity of the cable adds nothing at this time, and can only smear the reputation of that cable if you made an errant observation. Well, the cable is long since gone, so I can't do that. It was about nine years ago anyway. I don't believe it is even in that manufacturers line any longer (which may mean mine wasn't the only negative reaction). All I will say is that it was from a well known and reputable manufacturer. I thought perhaps you had some idea of what the "bad" cables were by name. BTW, you can cause a great deal of "bass clamping" if you reverse the phase of one of the cables. In that case, even my wife knew that something was wrong |
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(Mkuller) wrote:
Mkuller wrote: Research - The program used is tested beforehand to determine the artifact's audibility within it. Audio - Usually music is the program which is a very *insensitive* source. "Bob Marcus" Why would a program be tested beforehand to determine an artifact's audibility, when the point of the research itself is to determine the artifact's reliability? What evidence do you have that music is any less insensitive under any other test that doesn't involve the imagination? Come on, real evidence. Thank you for making my point. If the differences between two amplifiers happen to be a difference in frequency response at 12kHz and the program chosen is sensitive only up to 11kHz you will get...null results. I beleive it was jj who corrected me when I said that DBTs were insensitive - he said the test isn't but music as a program is. Part of the problem with music is that it is dynamic, ever-changing and audible memory is notoriuosly poor at hanging on to differences with a dynamic program. It is true that music is generally much less sensitive than test signals. Yet, audiophiles have no trouble pointing out large, night and day, pretty amazing differences using music as a source in uncontrolled listening sessions. What do you use? If you're going to lecture us about the scientific method, you ought to try practicing a little of it. It's not enough to claim that a test had some element that you suspect would affect its reliability. You must also offer some evidence that this element actually can affect its reliability. Until you have such evidence, you are talking through your hat. In the meantime, the paradigm for testing audible differences stands. From your questions it's pretty obvious that you don't have an real experience or knowledge in applying DBTs scientifically. Neither do you it would appear :-) I've explained where I see some important differences in their application between research and audio and all you can do is turn the question around and ask me for proof. I'm looking for proof that DBTs actually work in comparing audio components with music and don't obscure the subtle audible differences. From my experience and scientific knowledge it appears to me that they don't. It looks to me that you are only complaining because you don't like the results. There's nothing wrong with questioning; many have, but none of them has produced any real evidence that anything is sonically obscured with listening bias controls. The data suggests that listening without rigorous bias control routinely delivers false positives. Indeed, my own research shows that humans, including experienced audio enthisiasts, will regularly report sonic differences between 2 identical sound presentations delivered one after another. I have told you that I believe they do this because of the way the brain works in storing and recalling audible memory. Relaxed listening uses a different part of the brain than the matching/decision-making required in ABX. Results with non-ABX protocols have delivered the same results. Besides there's nothing except bias-controls and a fixed protocol that precludes "relaxed" listening. Indeed that's one of the big advantages of the process ... it encourages attention. The other is the gathering of analyzable data. So far the only differences DBTs seem to reveal in audio component testing are big ones - gross frequency response and loudness (i.e. as in speakers or bright CD players). If you have proof or evidence that DBTs actually work for the use you are suggesting, please provide it to me. They actually do 'work.' What you seem to want is evidence that they produce reults that fit with your pre-held beliefs even when it's not really the truth of the matter. If not, you are welcome to your belief system and I'll stick to mine. Regards, Mike I'll go with the methods that produce reliable data on sonc truth. You can stick to your beliefs. |
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clarifying conditions for $4k challenge
(Stewart Pinkerton) wrote in message ...
On Fri, 16 Jan 2004 04:11:56 GMT, (Buster Mudd) wrote: But now you're saying no audible differences "except for frequency response anomalies" ...or no audible differences except for those that can be matched with a couple dollars worth of passive components. I'm just trying to get a handle on what the rules of this game are. Note that any cable which does *not* have a flat FR is *by definition* not a competent cable. It's not an accurate cable, certainly. But conceivably it could be a perfectly competantly designed cable with intentionally euphonic innaccuracies, no? Regardless of whether one believes this is a desireable practice in audio, one has to admit that it is an available practice in audio. However, it's no big deal to match the FR of any particularly weird cable with a couple of buck's worth of passive components. Are you suggesting that this is somehow cheating?! yes, actually, it does seem like cheating. If you have to fudge the product, by introducing more hardware into the test apparatus in order to level the playing field (so to speak), you are no longer comparing A to B. I certainly understand how critically important level matching at a single reference frequency is...but if having done so, frequency response anomalies are evident, one would have to concede that the two products under test probably sound different. And if the 'boutique' cable is non-flat, then would you agree that it is *by definition* inferior? I would agree, absolutely. I am aware that there are some listeners (or, heaven forfend, some cable designers) that might disagree, but that is their prerogative. Again, I thought your contention was that those who claim they can hear the difference between 2 different speaker cables (or interconnects) are only imagining those differences. I didn't realize that a precondition of the test was that the cables actually had to sound identical. If there's an audible difference between cable A & cable B, that difference must be audible ALL OTHER THINGS BEING EQUAL. If all other things are NOT equal, you're not really comparing Cable A to Cable B, your comparing Cable A (+X) to Cable B (where X is some other variable that, if I understand you correctly, causes Cable A to ...duh! sound like Cable B!) Nope, we are making sure that ultra-cheap cable A has the same gross LCR characterictics as ultra-expensive cable B. Check any 'boutique' cable adverts, you will *never* see basic FR differences referenced as having anything to do with the claimed sonic superiority of those cables Again, I didn't think the $4k challenge was contingent upon specific claims of various manufacturers, I thought it was directed at claims of listeners who contend they can discern an audible difference between say, Home Depot 12awg zip cord & the boutique cable of their choice. What the marketing spin doctors have said in advertisements or "technical papers" about that boutique cable of choice should be immaterial in a test designed simply to prove or disprove whether or not the listener's claim is valid, no? |
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clarifying conditions for $4k challenge
Buster Mudd wrote:
I would agree, absolutely. I am aware that there are some listeners (or, heaven forfend, some cable designers) that might disagree, but that is their prerogative. Again, I thought your contention was that those who claim they can hear the difference between 2 different speaker cables (or interconnects) are only imagining those differences. I didn't realize that a precondition of the test was that the cables actually had to sound identical. No, the precondition is that they have to measure within nominal standards (0.1 dB from 20 Hz to 10KHz is what Stewart uses). Whether they actually sound identical, that's what the $4K (now much higher) challenge is designed to find out. If you are saying that any two cables that measures within that tolerance has to sound the same, well, that's exactly our position, too. But the cable believers *know* that the cable sound is due to some superior quality intrinsic in the cable, and does not show up in simple frequency response measurements. That's what the cable challenge is intended to debunk. By the way, you're overly concerned with the requirement that Stewart laid down. I would say that 95+% of all cables, zip-cord or boutique, meet that requirement handily. |
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clarifying conditions for $4k challenge
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more rules of $4k challenge questions
(Stewart Pinkerton) wrote in message ...
On 16 Jan 2004 03:08:42 GMT, (Buster Mudd) wrote: Though that doesn't quite explain how a Snake Oil Advocate would go about separating the (quote-unquote) "objectivists" from their hard earned +/- $4000. Easy - just prove you can hear a difference. Yet I got the impression from Bob Marcus' earlier statement if a difference is really heard, it will be the result of resistance-related (or perhaps inductance/capacitance related) frequency response anomalies that the "objectivists" were allowing that differences may be discernable, they were just attributable to fundamentals of electricity rather than voodoo & flooby-dust. If Joe Schmoe claims there is an audible difference between, say, Home Depot 12awg zip cord ($0.25/foot) and Tara Labs "The One" ($500/foot), & the ABX/DBT proctors claim "if a difference is really heard, it will be the result of resistance-related (or perhaps inductance/capacitance related) frequency response anomalies", shouldn't the proper response be "Ok, whatever" ...and then everyone just goes home & listens to music, in complete agreement. Where does this whole You Only *Think* You Can Hear The Difference challenge come into play? Easy, just sit down, *listen* to the two cables, and *prove* that you can hear a difference when you don't *know* which one's connected. That's all you have to do. So is it safe to conclude that you (Mr. Pinkerton) & Mr. Marcus are not in complete agreement on what the claims of the "Snake Oil Advocates" actually are, or how one would go about disproving their allegations? Bob says there might be differences but those differences have their origins in basic principles, not magical properties; Stewart says there aren't differences, period. Have I got that right? What, you are seriously suggesting that adding a couple of buck's worth of passive components to 12 AWG 'zipcord', in order to provide accurate level-matching to *any* $500 a foot cable, is somehow *cheating*?! Frankly I believe that if you add anything to the DUT you have compromised the test. Heisenberg & all that rot. This is what intrigues me most about this whole $4k cable challenge: not the claims of either camp, but the specifics of any testing methodology that would be endorsed by both camps. If I thought I could hear a difference between component A & component B, and a skeptic told me "Prove it by discerning a difference between component A & component B+C" I would feel as if they had misunderstood my original claim. (or that they were stacking the deck, as it were.) I understand the absolute necessity of level matching at a reference frequency. Yet you insist that if 2 cables which level match at one reference frequency do not level match at another, that aberration must be compensated for. I don't understand is how you can legitimately claim that this test methodology is a fair AB comparison, when you are no longer comparing A to B. |
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more rules of $4k challenge questions
Buster Mudd wrote:
Yet I got the impression from Bob Marcus' earlier statement if a difference is really heard, it will be the result of resistance-related (or perhaps inductance/capacitance related) frequency response anomalies that the "objectivists" were allowing that differences may be discernable, they were just attributable to fundamentals of electricity rather than voodoo & flooby-dust. snip So is it safe to conclude that you (Mr. Pinkerton) & Mr. Marcus are not in complete agreement on what the claims of the "Snake Oil Advocates" actually are, or how one would go about disproving their allegations? Bob says there might be differences but those differences have their origins in basic principles, not magical properties; Stewart says there aren't differences, period. Have I got that right? Nope. Stewart and I are in agreement. If we weren't, he wouldn't be insisting on the level-matching that has you so perplexed, would he? I'm just trying to explain why he's insisting on it, although I get the impression I'm not telling you anything you didn't already know. (Just remember--many audiophiles don't believe it.) I think you've missed the contribution of one other participant here, Chung, who said: By the way, you're overly concerned with the requirement that Stewart laid down. I would say that 95+% of all cables, zip-cord or boutique, meet that requirement handily. Unless there's something other than simple wire in that boutique cable (like those funny little boxes with resistors inside), it's very likely that we can buy cable off the shelf at Home Depot that will meet Stewart's requirement. So you needn't worry that we're cooking the test. Now, if there really are resistors in the signal path, all bets are off unless we can put resistors in our signal path, too. But our resistors won't cost hundreds of dollars. bob __________________________________________________ _______________ Scope out the new MSN Plus Internet Software — optimizes dial-up to the max! http://join.msn.com/?pgmarket=en-us&page=byoa/plus&ST=1 |
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