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#202
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Why do the anti-ABX folks not deliver?
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#203
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Why do the anti-ABX folks not deliver?
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#204
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Why do the anti-ABX folks not deliver?
(Bob Marcus) wrote in message ...
(ludovic mirabel) wrote in message news:slT_a.146770$uu5.22279@sccrnsc04... (Nousaine) wrote in message ... Nousaine said: Isn't that funny. No one can ever "prove a negative". So what? We should then ignore the fact that NO ONE has ever produced a single experiment that confirms "amplifier" or "wire" sound with even modest bias controls implemented. NO One' Ever!!!! I replied: According to your ABX coworker L. Greenhill (Stereo Review August 1982) one of his subjects did that very thing. So much for "NO one! Ever!!!!!" It is your privilege to disagree with Greenhill- you two ABXers fight it out. Marcus comments: Elsewhere today you tell us you are a published writer. Fiction a specialty? Anyone tempted to take Mirabel's assertion here at face value should consult the original article and read for himself that Greenhill said no such thing. bob This is what Greenhill said reporting the outcome of his cable comparison test: ("The Stereo Review, August 1982): "Final significant conclusion one can draw is that at least one genuine "golden ear" exists. Obviously certain listeners whether through talent, training or experience can hear small differences between components" Do not think that this is only the first time this was quoted to Mr. Marcus or that he made similar statement. He developed a technique of referring you to source that is difficult to track in the expectation (well justified in most cases) that you'll not bother. As he had done before he'll now probably fall silent for a few months and then return with more of the same counting on short memories. I'll let others find appropriate words.. Ludovic Mirabel |
#205
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Why do the anti-ABX folks not deliver?
(Stewart Pinkerton) wrote in message ...
On 15 Aug 2003 14:34:45 GMT, (Nousaine) wrote: My point isn't that every amplifier used in every test hasn't been replicated but that many tests had been published but none of those had results that matched those claimed by Stewart. That's OK; but until his results become documented and are replicated they remain anecdotal. So, how soon can you get here? :-) Ok, I have not been around this group that long, but I am pretty well on the objective side of the fence. My question is that both you, Stewart and Tom Nousaine seem to be objective, but apparently Stewart has come up with a different set of results in a DBT. Could you both elaborate without me searching the archives as to what was tested and the results. Thanks. |
#206
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Why do the anti-ABX folks not deliver?
Randy said
Question: I define sight bias as being suggestible to the way a component (or wire or interconnect etc.) looks, how much the price tag is, what subjective magazines say, etc. Do you beleive there is such a thing as "sight bias"? Yes. Randy said If so, is it something that is limited to a small population, if not, why not? No. Valid scientific studies have suggested it is not limmited to a small population. Randy said If you do beleive there is "sight bias", then who should have the "burden of proof" in proving audible differences in cables, amps, etc. If one contends their claim is scientifically valid then the one making the claim bears the burden of proof. That also goes for anyone making a claim of inaudibility as well. If you are saying it is a scientifically valid claim then you have to have the scientifically valid evidence to back it up. If you want to make a global claim of this nature you better have the mountain of ecidence that would be expected of such a claim. Randy said How would you go about it? Scientifically valid controled tests. Naturally. Randy said Do you care? Yeah. Randy said If not, why "debate" Tom and others? |
#207
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Why do the anti-ABX folks not deliver?
(Stewart Pinkerton) wrote in message ...
On 15 Aug 2003 14:34:45 GMT, (Nousaine) wrote: My point isn't that every amplifier used in every test hasn't been replicated but that many tests had been published but none of those had results that matched those claimed by Stewart. That's OK; but until his results become documented and are replicated they remain anecdotal. So, how soon can you get here? :-) Ok, I have not been around this group that long, but I am pretty well on the objective side of the fence. My question is that both you, Stewart and Tom Nousaine seem to be objective, but apparently Stewart has come up with a different set of results in a DBT. Could you both elaborate without me searching the archives as to what was tested and the results. Thanks. |
#208
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Why do the anti-ABX folks not deliver?
Tom said
Please. I accept any and all "evidence." Stewart's experiments have not been documented nor have they been replicated. The latter isn't his responsibility. The former is. I said The tests in the reports you sent me haven't been replicated either. Tom said Actualy they were all replications of each other No they weren't. The equipment, the rooms and the protocol were different in each test. They certianly weren't replications fo each other. My point isn't that every amplifier used in every test hasn't been replicated but that many tests had been published but none of those had results that matched those claimed by Stewart. Well. there goes the claim that no test produced an audible difference. If all the tests in question have accurately reported the equipment, room and sound sources used then they are all replicable. I think Stewert's tests fall under that criteria. Tom said That's OK; but until his results become documented and are replicated they remain anecdotal. Sorry but this new criteria of tests having to be "replicated" to be more than anecdotal is nonsense. You can make your own rules of evidence up as you go along but you won't have any established scientific basis for your claims. As I said before, many long term scientific tests have not been "replicated" but are considered to be good, valid scientific tests. I said Doesn't matter. What matters is if the are replicable. Stewert says he has documented his tests. I see no reason to think he is lying. Tom said Oh for Christsakes' as of 1990 there had been been 2 dozen documented and published bias controlled listening tests of power amplifiers that basicallt showed that any device with flat response that wasn't hampered by operating fault or high output impedance were sonically transparent....so why do we need any more evidence on this matter??????? I said And this emotional outburst has what to do with my post? How many of those tests were "replicated?" If that is the new criteria you are pushing for tests to be valid then it seems you may have very little evidence on the issue at all. that would be cause alone for more testing I would think. If you don't want to test any more then don't. Tom said What is so interesting is that you appear to be willing to accept anything that appears to support your position without scrutiny. Then there is a problem with your perception. Tom said You don't happen to be in the market for a bridge? I'm not buying any bridges or your personal rules of evidence. |
#209
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Why do the anti-ABX folks not deliver?
Stewert said
As has been noted before, you can't get published in a peer-reviewed technical magazine for pointing out the bleedin' obvious! I said AESJ certainly has published at least one article that only argued the superiority of DBTs over sighted tests. Isn't that in the category of "bleedin' obvious!"??? There is no reason to my knowledge that the AESJ would not publish reports of tests were anyone to try to do so. Can you think of any such Can you think of any such reports that were rejected by the AESJ on the grounds of excessive obviousness? Arny said AFAIK, the activities of the AES Journal Review board are not public. Therefore nobody knows for sure other than the board members and they don't talk about this a whole lot. I said It is known for sure by certain people. If anyone has any claims that they have submitted reports of such tests to the AESJ that were rejected for publication on the grounds that it was simply too obvious for publication, then any such person is invited to speak up. Till some one does it is nothing more than wild speculation to claim that any such thing has happened. Howard said Why are you so interested in what others have done or should be doing? Why are you not? Why shouldn't I be? At the risk of aounding less than modest, I am very good at what I do. What I do is not research in audio. Howard said have done or should be doing? Why not just do a series of carefully level matched double blind, or at least single blind comparisons yourself (it's not THAT hard) and discover whether you can or cannot hear differences? 1. It is hard to do valid ABX DBTs 2. I don't have the time or the hardware 3. I'm not considering a purchase of any amplifier at this time. Howard said After all, the only thing that really matters is whether those differences are audible to you, Well, generally speaking, one could use this point to say there is no need to bother with DBTs for amps. If one thinks they hear a difference and is happy with what they think then that's it. Happy camper. Howard said and you seem to be very, very interested in whether or not differences between amps or between wires are audible. I am interested in it. It isn't very high on things to do list. Howard said If someone else did a definitive series of "no audible differences" comparisons and had the results published in the JAES it still would not tell you if you could have heard differences. That depends on the study. If amps all sound the same provided they are "competently" designed and built and are operated within their power limmits then a good, large scale scientific study could offer a very compelling conclusion about whether or not I can possibly hear differences between such amps IMO. Howard said Do some comparing yourself, in order to satisfy you and not somebody else. I did that years ago. |
#210
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Why do the anti-ABX folks not deliver?
On 15 Aug 2003 21:30:28 GMT, (Nousaine) wrote:
(Stewart Pinkerton) wrote: On 15 Aug 2003 14:34:45 GMT, (Nousaine) wrote: My point isn't that every amplifier used in every test hasn't been replicated but that many tests had been published but none of those had results that matched those claimed by Stewart. That's OK; but until his results become documented and are replicated they remain anecdotal. So, how soon can you get here? :-) That would be a god project now, wouldn't it. You going to be at the AES in New York or perhaps in Munich next year? Sorry no, I never have time for such jaunts these days. OTOH, I'll happily provide bed and board if you're in the English midlands sometime. -- Stewart Pinkerton | Music is Art - Audio is Engineering |
#211
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Why do the anti-ABX folks not deliver?
On 15 Aug 2003 21:30:55 GMT, (randyb) wrote:
(Stewart Pinkerton) wrote in message ... On 15 Aug 2003 14:34:45 GMT, (Nousaine) wrote: My point isn't that every amplifier used in every test hasn't been replicated but that many tests had been published but none of those had results that matched those claimed by Stewart. That's OK; but until his results become documented and are replicated they remain anecdotal. So, how soon can you get here? :-) Ok, I have not been around this group that long, but I am pretty well on the objective side of the fence. My question is that both you, Stewart and Tom Nousaine seem to be objective, but apparently Stewart has come up with a different set of results in a DBT. Could you both elaborate without me searching the archives as to what was tested and the results. Thanks. We were burgled (grrr!) and I had to replace my TV sound system, so I was in the market for a new amplifier. I had just purchased my Apogee Duetta Signatures and Krell KSA-50mkII amp, so I had a good 'reference' amp and a tough speaker load with exceptional clarity and 'openness'. I had also settled on Tannoy 633 speakers for the TV system (in my view, you buy speakers you like, then you buy an amp which can drive them). I assembled a 4-pole switch-box with relay connections, and a 3-way switch enabling me to select A, B or 'X', with X being set by a hidden toggle switch on the relay box. The 'X' switch had a central 'off' position, so that each reset used two clicks of the switch. I also made up a 4-channel attenuator, enabling me to set the gains of each channel of a pair of stereo amps to be matched within +/- 0.1dB. Next, I entered negotiations with some local hi-fi dealers, and over a period of a couple of weeks or so, I was able to borrow a pair of Denon POA6600 monoblocks, a Hafler XL600, an Arcam Xeta One, a Yamaha 2090, a Yamaha AX-570, A Rega Elex, A Musical Fidelity E600, an Audiolab 8000A, and an Audiolab 8000P. I set up a series of 20 trials of each amp, with my wife doing the switching. She flipped a coin 20 times, and noted on a score sheet whether it was heads or tails. She set the 'X' switch to A for heads and B for tails after each test. I'd satisfy myself as to the identity of X and mark it on a score sheet, my wife would enter the room, reset the identity of 'X' and leave the room while I conducted the next test. The end result was that the Denons (fave rave reviews in all the rags at the time) and the Rega were instantly tossed for rough treble, the MF was instantly tossed for a 'veiled' sound with recessed treble, the Yamaha 2090 and Arcam were tossed for slightly bright treble, while the remaining amps were too close to call. Retesting of the Audiolab 8000A revealed a *slight* veiling of the sound, but it just crept into the '16 out of 20' target score, while the Yamaha AX-570, the cheapest amp on test, was a real surprise. I got 15/20 correct, but only revealed by a slight treble brightness on viloin solos. The Hafler and the Audiolab 8000P were sonically identical to the Krell, no better than 12/20 on original or retest. The Hafler, probably the best all-rounder as it was very powerful as well as quiet and sonically impeccable, was rejected on the grounds of its horrendously noisy cooling fan, leaving the Audiolab 8000P as the 'winner'. Truth to tell, on the Tannoy speakers I couldn't hear any significant deterioration with the AX-570, but I liked the compact size and 'less is more' approach of the Audiolab, so I stumped up the extra, and it's still serving me well after about 8 years, as is the venerable Krell. I should perhaps mention that I'd actually traded in an older 8000P against the Krell when I bought the Duettas, as the Audiolab got *very* hot after playing some heavy rock music through these insensitive 3-ohm monsters. The Krell didn't put out any more power, but being designed to play continuously into 1 one-ohm load, it wasn't at all bothered about driving the Apogees. As a bizarre aside to the above, I published these test results just a few weeks before the notorious 'Sunshine Trials', where a very vocal (sadly now deceased) 'audiophile' dealer failed to distinguish his favourite exotic Pass Labs Aleph 1.2 monoblocs from an old integrated Yamaha amp (an A-700, IIRC), on his own reference sound system. Steve Maki and Tom Nousaine proctored this test, and Tom was later accused of bringing in the Yamaha as a 'ringer', in view of the exceptional performance of the AX-570 in my own tests. Obviously a gross cheat, eh, sneaking in a good-sounding $500 integrated amp to beat up a $12,000 pair of 'designer label' power amps! -- Stewart Pinkerton | Music is Art - Audio is Engineering |
#212
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Why do the anti-ABX folks not deliver?
"Stewart Pinkerton" wrote
We were burgled (grrr!) and I had to replace my TV sound system, so I was in the market for a new amplifier. I had just purchased my Apogee Duetta Signatures and Krell KSA-50mkII amp, so I had a good 'reference' amp and a tough speaker load with exceptional clarity and 'openness'. I had also settled on Tannoy 633 speakers for the TV system (in my view, you buy speakers you like, then you buy an amp which can drive them). I assembled a 4-pole switch-box with relay connections, and a 3-way switch enabling me to select A, B or 'X', with X being set by a hidden toggle switch on the relay box. The 'X' switch had a central 'off' position, so that each reset used two clicks of the switch. I also made up a 4-channel attenuator, enabling me to set the gains of each channel of a pair of stereo amps to be matched within +/- 0.1dB. Next, I entered negotiations with some local hi-fi dealers, and over a period of a couple of weeks or so, I was able to borrow a pair of Denon POA6600 monoblocks, a Hafler XL600, an Arcam Xeta One, a Yamaha 2090, a Yamaha AX-570, A Rega Elex, A Musical Fidelity E600, an Audiolab 8000A, and an Audiolab 8000P. I set up a series of 20 trials of each amp, with my wife doing the switching. She flipped a coin 20 times, and noted on a score sheet whether it was heads or tails. She set the 'X' switch to A for heads and B for tails after each test. I'd satisfy myself as to the identity of X and mark it on a score sheet, my wife would enter the room, reset the identity of 'X' and leave the room while I conducted the next test. The end result was that the Denons (fave rave reviews in all the rags at the time) and the Rega were instantly tossed for rough treble, the MF was instantly tossed for a 'veiled' sound with recessed treble, the Yamaha 2090 and Arcam were tossed for slightly bright treble, while the remaining amps were too close to call. Retesting of the Audiolab 8000A revealed a *slight* veiling of the sound, but it just crept into the '16 out of 20' target score, while the Yamaha AX-570, the cheapest amp on test, was a real surprise. I got 15/20 correct, but only revealed by a slight treble brightness on viloin solos. The Hafler and the Audiolab 8000P were sonically identical to the Krell, no better than 12/20 on original or retest. The Hafler, probably the best all-rounder as it was very powerful as well as quiet and sonically impeccable, was rejected on the grounds of its horrendously noisy cooling fan, leaving the Audiolab 8000P as the 'winner'. Truth to tell, on the Tannoy speakers I couldn't hear any significant deterioration with the AX-570, but I liked the compact size and 'less is more' approach of the Audiolab, so I stumped up the extra, and it's still serving me well after about 8 years, as is the venerable Krell. I should perhaps mention that I'd actually traded in an older 8000P against the Krell when I bought the Duettas, as the Audiolab got *very* hot after playing some heavy rock music through these insensitive 3-ohm monsters. The Krell didn't put out any more power, but being designed to play continuously into 1 one-ohm load, it wasn't at all bothered about driving the Apogees. As a bizarre aside to the above, I published these test results just a few weeks before the notorious 'Sunshine Trials', where a very vocal (sadly now deceased) 'audiophile' dealer failed to distinguish his favourite exotic Pass Labs Aleph 1.2 monoblocs from an old integrated Yamaha amp (an A-700, IIRC), on his own reference sound system. Steve Maki and Tom Nousaine proctored this test, and Tom was later accused of bringing in the Yamaha as a 'ringer', in view of the exceptional performance of the AX-570 in my own tests. Obviously a gross cheat, eh, sneaking in a good-sounding $500 integrated amp to beat up a $12,000 pair of 'designer label' power amps! -- Stewart Pinkerton | Music is Art - Audio is Engineering Thank you, Mr. Pinkerton. This is the first post I have seen on testing on RAHE that was specific to the point of usefulness.. It shows that excellent products can be had at moderate prices, and that a number of higher priced products may be noticeasbly inferior. Your project was a large expenditure of time and energy, which many of us are not willing to undertake unless we are in the market for a component. But as a hobbist I would like to regularly read about the results of such tests in hopes that something truly better turned up in the world of high end. It makes me wonder why reveiwers for the audiophile magazines don't do ABX testing. If it were true that "all amps sound alike" reviewers would not want to publicize that fact because they are in the business of writing about differences. But there are diffrences so that reasoning is out, and their jobs are secure. Wylie Williams. |
#213
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Why do the anti-ABX folks not deliver?
"Wylie Williams" wrote in message news:fnt%a.127470$cF.34056@rwcrnsc53...
"Stewart Pinkerton" wrote We were burgled (grrr!) and I had to replace my TV sound system, so I was in the market for a new amplifier. I had just purchased my Apogee Duetta Signatures and Krell KSA-50mkII amp, so I had a good 'reference' amp and a tough speaker load with exceptional clarity and 'openness'. I had also settled on Tannoy 633 speakers for the TV system (in my view, you buy speakers you like, then you buy an amp which can drive them). I assembled a 4-pole switch-box with relay connections, and a 3-way switch enabling me to select A, B or 'X', with X being set by a hidden toggle switch on the relay box. The 'X' switch had a central 'off' position, so that each reset used two clicks of the switch. I also made up a 4-channel attenuator, enabling me to set the gains of each channel of a pair of stereo amps to be matched within +/- 0.1dB. Next, I entered negotiations with some local hi-fi dealers, and over a period of a couple of weeks or so, I was able to borrow a pair of Denon POA6600 monoblocks, a Hafler XL600, an Arcam Xeta One, a Yamaha 2090, a Yamaha AX-570, A Rega Elex, A Musical Fidelity E600, an Audiolab 8000A, and an Audiolab 8000P. I set up a series of 20 trials of each amp, with my wife doing the switching. She flipped a coin 20 times, and noted on a score sheet whether it was heads or tails. She set the 'X' switch to A for heads and B for tails after each test. I'd satisfy myself as to the identity of X and mark it on a score sheet, my wife would enter the room, reset the identity of 'X' and leave the room while I conducted the next test. The end result was that the Denons (fave rave reviews in all the rags at the time) and the Rega were instantly tossed for rough treble, the MF was instantly tossed for a 'veiled' sound with recessed treble, the Yamaha 2090 and Arcam were tossed for slightly bright treble, while the remaining amps were too close to call. Retesting of the Audiolab 8000A revealed a *slight* veiling of the sound, but it just crept into the '16 out of 20' target score, while the Yamaha AX-570, the cheapest amp on test, was a real surprise. I got 15/20 correct, but only revealed by a slight treble brightness on viloin solos. The Hafler and the Audiolab 8000P were sonically identical to the Krell, no better than 12/20 on original or retest. The Hafler, probably the best all-rounder as it was very powerful as well as quiet and sonically impeccable, was rejected on the grounds of its horrendously noisy cooling fan, leaving the Audiolab 8000P as the 'winner'. Truth to tell, on the Tannoy speakers I couldn't hear any significant deterioration with the AX-570, but I liked the compact size and 'less is more' approach of the Audiolab, so I stumped up the extra, and it's still serving me well after about 8 years, as is the venerable Krell. I should perhaps mention that I'd actually traded in an older 8000P against the Krell when I bought the Duettas, as the Audiolab got *very* hot after playing some heavy rock music through these insensitive 3-ohm monsters. The Krell didn't put out any more power, but being designed to play continuously into 1 one-ohm load, it wasn't at all bothered about driving the Apogees. As a bizarre aside to the above, I published these test results just a few weeks before the notorious 'Sunshine Trials', where a very vocal (sadly now deceased) 'audiophile' dealer failed to distinguish his favourite exotic Pass Labs Aleph 1.2 monoblocs from an old integrated Yamaha amp (an A-700, IIRC), on his own reference sound system. Steve Maki and Tom Nousaine proctored this test, and Tom was later accused of bringing in the Yamaha as a 'ringer', in view of the exceptional performance of the AX-570 in my own tests. Obviously a gross cheat, eh, sneaking in a good-sounding $500 integrated amp to beat up a $12,000 pair of 'designer label' power amps! -- Stewart Pinkerton | Music is Art - Audio is Engineering Thank you, Mr. Pinkerton. This is the first post I have seen on testing on RAHE that was specific to the point of usefulness.. It shows that excellent products can be had at moderate prices, and that a number of higher priced products may be noticeasbly inferior. Your project was a large expenditure of time and energy, which many of us are not willing to undertake unless we are in the market for a component. But as a hobbist I would like to regularly read about the results of such tests in hopes that something truly better turned up in the world of high end. It makes me wonder why reveiwers for the audiophile magazines don't do ABX testing. If it were true that "all amps sound alike" reviewers would not want to publicize that fact because they are in the business of writing about differences. But there are diffrences so that reasoning is out, and their jobs are secure. Wylie Williams. I would restrain enthusiasm Mr. Williams if I were you. Mr. Pinkertons results nwere achieved with his set of musical experience and preferences, his exposure , his ancillary equipment and above all his ears and his temporal lobes of the brain. There is very little likelihood that your results would be anywhere like his. Look at the record of fivergencies between the participating individuals in all the "listening tests" available so far. Only your switch would be identical. Nothing else. If you're buying I'd redo it all with your own physical and psychological resources first. You may like whatever Mr. Pinkerton does or you may not. Ludovic Mirabel |
#214
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Why do the anti-ABX folks not deliver?
(Nousaine) wrote in message .net...
(S888Wheel)wrote: ..snips....... Please. I accept any and all "evidence." Stewart's experiments have not been documented nor have they been replicated. The latter isn't his responsibility. The former is. The tests in the reports you sent me haven't been replicated either. Doesn't matter. What matters is if the are replicable. Stewert says he has documented his tests. I see no reason to think he is lying. Oh for Christsakes' as of 1990 there had been been 2 dozen documented and published bias controlled listening tests of power amplifiers that basicallt showed that any device with flat response that wasn't hampered by operating fault or high output impedance were sonically transparent....so why do we need any more evidence on this matter??????? I reviewed two extensive relevant bibliographies published in RAHE by Mtry Craft and Klaus Rampelman. There was one only (1) published panel ABX "listening test" in the Stereo Review 1982- of course with a negative result. Mr' Krueger and his two supertrained ABX codevelopers published one, too supposedly positive but hardly representative of the average audiophile crowd. If you have "2 dozen" please give references (Mag, author, year, month, page) to a few of them to begin with. You surely are too responsible to join those who said one ane and all that they had "many" , "numerous" and when pressed against the wall kept silent. As for Oakland comparisons of 10 watt DIY Heathkit against 400 watt Dynaco surely you'll not bring up that one again.( you did once) It was funny ha ha "positive" anyway. They could tell the difference, believe it or not. Ludovic Mirabel |
#215
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Why do the anti-ABX folks not deliver?
On Sat, 16 Aug 2003 16:56:43 GMT, "Wylie Williams"
wrote: Your project was a large expenditure of time and energy, which many of us are not willing to undertake unless we are in the market for a component. But as a hobbist I would like to regularly read about the results of such tests in hopes that something truly better turned up in the world of high end. It makes me wonder why reveiwers for the audiophile magazines don't do ABX testing. If it were true that "all amps sound alike" reviewers would not want to publicize that fact because they are in the business of writing about differences. But there are diffrences so that reasoning is out, and their jobs are secure. Unfortunately, while there are still many poorly designed amps on sale at very high prices (almost all of the single-ended triode variety), there is also a huge raft of very competent designs which I am reasonably sure would *not* show audible differences in a level-matched DBT. This would rather cut the rug from under such 'golden eared' reviewers as Martin Colloms and his bizarre points scoring system, so you're unlikely to see DBTs in the audio ragazines any time soon. -- Stewart Pinkerton | Music is Art - Audio is Engineering |
#216
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Why do the anti-ABX folks not deliver?
On 16 Aug 2003 17:18:15 GMT, "Dennis Moore"
wrote: Okay Stewart, you detailed how you selected for a new amp to use on Tannoy speakers. You tell how in blind testing some had rough treble or veiled recessed sound etc. And how you found a couple affordable amps that were indistinguishable from the Krell. So do you have any idea what about the discernibly different amps was responsible for the difference in perceptible sound? Since the tests were done for the express purpose of making a purchase decision, I did not do any follow-up testing on the rejects. I am pretty sure on basic thd, frequency response etc. that most of those amps would have tested below known levels of audibility especially with fairly easy loads like the Tannoy. I suspect that the MF unit would have shown a drooping treble, it really was noticeably 'dull' in sound. I also suspect that the Rega and the two AV amps would have shown excessive HF IMD and/or crossover distortion, as these are typical culprits causing rough or bright treble. As some people here have asked many times, what objective specification(s) would have made it possible for you to reject those other amps without needing a blind test? For myself, I'd consider it unlikely that I could hear differences among amps which met the following criteria: 1) Full-power 19/20kHz IMD below -90dB 2) No harmonic distortion above -90dB, from 10Hz to 20kHz fundamentals, driving full power into a 4-ohm load, with all artifacts descending smoothly below the noise floor as the output power is reduced. 3) The ability to drive a 2-ohm load at an output power at least 3 times higher than full power into an 8-ohm load. Others may have different criteria, and it's certainly possible that an amp which had noticeably higher THD (but of a benign low-order nature) would also be sonically impeccable. -- Stewart Pinkerton | Music is Art - Audio is Engineering |
#217
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Why do the anti-ABX folks not deliver?
(Bob Marcus) wrote in message news:mJf%a.121814$cF.33270@rwcrnsc53...
And while we're at it, let us note that the man who insists that we have provided no evidence that anyone can distinguish audio components using ABX nonetheless claims (wrongly, as we see) that this subject did so distinguish them? What's the appropriate word for that? bob We'll start right here. I'm supposed to "insist " that "we" "have provided no evidence that ANYONE (my capitals L.M.) can distinguish audio components using ABX...etc. My first reaction to the attribution to ME of these stupid beliefs is outrage. Why should I or indeed anyone be forced to straighten out boringly and for the nth time someone's travesty? For the last two years I have been repeating that 1) there are differences between components 2) they are audible to some and not audible to others 3) explicitly, in those words and within te last two weeks I repeated (see the (Why DBTs in audio do not..." July 25 posting) that talented or supertrained listeners such as Pinkerton, Krueger, Clark and Greenhill's "golden ear" will still hear them even when ABxing. 4) that reporting as the end-outcome the majority vote of ABX untrained/untalented and ignoring the capable minority who DO hear-exactly the way Greenhill had done (see Marcus quotes)is a perversion of "testing". Now Marcus should know all that. He's been arguing for the last two years against myself and Harry Lavo that Greenhill was perfectly right basing his conclusions on the incapable majority and ignoring what Greenhill himself (rather unusually- the ABXing proctors, who followed him, did not copy his honesty)- called a true "golden ear". Today Marcus chooses to attribute to me the exact opposite of what I argued for: a strange assertion that NO ONE "..can distinguish the audio componments using ABX" But then another possibility occurs. Maybe he is not just bent on winning any which way. Maybe he really *believes* the nonsense he is voicing loudly.. This is not the first time either- he's a repeater. Look at the clever-clever but very transparent way he goes about obfuscating the sense of clear and *emphatic* Greenhill's own words. Surely he couldn't believe that he convinces anyone ...unless he managed to convince himself first. Perhaps he is no Macchiavelli. Perhaps he is simply unable to grasp the meaning of a simple text. This possibility would be in keeping with his stance throughout. His sending people who know more about the subject than he does for refresher courses he did so send me, Harry Lavo and some others), his preaching about what "we" (ie. Marcus) say is the truth about everything under the sun: electronics, psychometrics, statistics. When it is quite obvious that eg. he never got beyond the first two chapters of something like "Introduction to statistics for lawyers" and misunderstood those to boot. Would he otherwise talk about statistical "double humps" when discussing a panel of eleven (yes 11) listeners or insist that it is OK to add up all the random (50/50) correct guesses of all the eleven panelists, good performers' results pulling up the bad ones to get a group "positive" result to his liking? Thus obfuscating what really mattered: that a few did hear and most did not. Or quote a recognition of gross electrical difference between cables as a "positive Marcus- Ovchain 1,75 db test" It is a chore to have to restate the same every few months. And just as productive. Ludovic Mirabel (ludovic mirabel) wrote in message news:0%a%a.152106$uu5.23006@sccrnsc04... (Bob Marcus) wrote in message ... (ludovic mirabel) wrote in message news:slT_a.146770$uu5.22279@sccrnsc04... (Nousaine) wrote in message ... Nousaine said: Isn't that funny. No one can ever "prove a negative". So what? We should then ignore the fact that NO ONE has ever produced a single experiment that confirms "amplifier" or "wire" sound with even modest bias controls implemented. NO One' Ever!!!! I replied: According to your ABX coworker L. Greenhill (Stereo Review August 1982) one of his subjects did that very thing. So much for "NO one! Ever!!!!!" It is your privilege to disagree with Greenhill- you two ABXers fight it out. Marcus comments: Elsewhere today you tell us you are a published writer. Fiction a specialty? Anyone tempted to take Mirabel's assertion here at face value should consult the original article and read for himself that Greenhill said no such thing. bob This is what Greenhill said reporting the outcome of his cable comparison test: ("The Stereo Review, August 1982): "Final significant conclusion one can draw is that at least one genuine "golden ear" exists. Obviously certain listeners whether through talent, training or experience can hear small differences between components" Well, yes, obviously. The question is, how small? And here was Greenhill's answer: "So what do our fifty hours of testing, scoring, comparing, and listening to speaker cables amount to? Only that 16-gauge lamp cord and Monster Cable are indistinguishable from each other with music . . . This project was unable to validate the sonic benefits claimed for exotic speaker cables over common 16-gauge zip cord." Do not think that this is only the first time this was quoted to Mr. Marcus or that he made similar statement. Nope. I point out your fanciful misinterpretation every time you make it. He developed a technique of referring you to source that is difficult to track in the expectation (well justified in most cases) that you'll not bother. I'd be happy to e-mail the article to anyone who asks. As he had done before he'll now probably fall silent for a few months and then return with more of the same counting on short memories. I'll let others find appropriate words.. Ludovic Mirabel |
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Why do the anti-ABX folks not deliver?
On Sat, 16 Aug 2003 16:56:43 GMT, "Wylie Williams"
wrote: Your project was a large expenditure of time and energy, which many of us are not willing to undertake unless we are in the market for a component. But as a hobbist I would like to regularly read about the results of such tests in hopes that something truly better turned up in the world of high end. It makes me wonder why reveiwers for the audiophile magazines don't do ABX testing. If it were true that "all amps sound alike" reviewers would not want to publicize that fact because they are in the business of writing about differences. But there are diffrences so that reasoning is out, and their jobs are secure. "Stewart Pinkerton" replied in message ... Unfortunately, while there are still many poorly designed amps on sale at very high prices (almost all of the single-ended triode variety), there is also a huge raft of very competent designs which I am reasonably sure would *not* show audible differences in a level-matched DBT. This would rather cut the rug from under such 'golden eared' reviewers as Martin Colloms and his bizarre points scoring system, so you're unlikely to see DBTs in the audio ragazines any time soon. The problem I have in deciding if I should upgrade my systems's amp is that I only have access to amps that are reviewed by magazines as being very fine (Parasound and HALO). As I read it on RAHE these magazine reviews may not be at all reliable. I may not have been unfortunate enough to have ever had a well designed amp in my system, and even if I were to borrow a few I have no idea that they would be amps from the limited group of "competent designs". I have listened mostly to Parasound and HALO, with side trips to YBA, and HK Citation 1, but RAHE experts tell me that there is no way to find out if these are good guys or bad guys. The only way is to gather a bunch of amps and do ABX tests for myself. But I don't even know the identity of amps can be used as reference example of good amps. RAHE tells me they exist, but nobody can make their fingers hit those keys to name brands and models. This leads to a secondary but related point - Given the number of participants who assure the group repeatedly that they are truly experts, what is most surprising is how little specific information they post. Any nunber of people are willing to go into endless detail about why someone else does not really understand DBT, ABX, cables, wires, jitter, how stupid audio designers are. etc. etc. etc., but the one post of yours describing your personal tests of several years ago was the first one that gave specifics. Naturally it has been questioned. What can explain the absence of helpful specifics on RAHE? Is there a code of "Don't ask - Don't tell"? Wylie Williams |
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Why do the anti-ABX folks not deliver?
(ludovic mirabel) wrote in message news:fLP%a.137308$cF.38433@rwcrnsc53...
(Bob Marcus) wrote in message news:mJf%a.121814$cF.33270@rwcrnsc53... And while we're at it, let us note that the man who insists that we have provided no evidence that anyone can distinguish audio components using ABX nonetheless claims (wrongly, as we see) that this subject did so distinguish them? What's the appropriate word for that? bob We'll start right here. I'm supposed to "insist " that "we" "have provided no evidence that ANYONE (my capitals L.M.) can distinguish audio components using ABX...etc. My first reaction to the attribution to ME of these stupid beliefs is outrage. Why should I or indeed anyone be forced to straighten out boringly and for the nth time someone's travesty? For the last two years I have been repeating that 1) there are differences between components 2) they are audible to some and not audible to others 3) explicitly, in those words and within te last two weeks I repeated (see the (Why DBTs in audio do not..." July 25 posting) that talented or supertrained listeners such as Pinkerton, Krueger, Clark and Greenhill's "golden ear" will still hear them even when ABxing. 4) that reporting as the end-outcome the majority vote of ABX untrained/untalented and ignoring the capable minority who DO hear-exactly the way Greenhill had done (see Marcus quotes)is a perversion of "testing". "Ignoring the minority who DO have fewer and less severe colds after megadosing vitamin C is a perversion of testing." See how silly that argument is? So stop using it. Now Marcus should know all that. He's been arguing for the last two years against myself and Harry Lavo Don't hide behind Harry. He may fudge his statistics on occasion, but he basically knows what he's talking about. that Greenhill was perfectly right basing his conclusions on the incapable majority and ignoring what Greenhill himself (rather unusually- the ABXing proctors, who followed him, did not copy his honesty)- called a true "golden ear". Who could hear what, that no one else in the test could hear? Nothing. Today Marcus chooses to attribute to me the exact opposite of what I argued for: a strange assertion that NO ONE "..can distinguish the audio componments using ABX" But then another possibility occurs. Maybe he is not just bent on winning any which way. Who's trying to win anything? I'm just correcting your mistatements, and referring people to the original source for confirmation. Maybe he really *believes* the nonsense he is voicing loudly.. This is not the first time either- he's a repeater. Look at the clever-clever but very transparent way he goes about obfuscating the sense of clear and *emphatic* Greenhill's own words. You mean the part where I quoted him verbatim? Yes, that's a clever tool of obfuscation. Surely he couldn't believe that he convinces anyone ...unless he managed to convince himself first. Perhaps he is no Macchiavelli. Perhaps he is simply unable to grasp the meaning of a simple text. Ah...no, I shouldn't, too easy. This possibility would be in keeping with his stance throughout. His sending people who know more about the subject than he does for refresher courses he did so send me, Harry Lavo and some others), his preaching about what "we" (ie. Marcus) say is the truth about everything under the sun: electronics, psychometrics, statistics. When it is quite obvious that eg. he never got beyond the first two chapters of something like "Introduction to statistics for lawyers" and misunderstood those to boot. Would he otherwise talk about statistical "double humps" when discussing a panel of eleven (yes 11) listeners Jeez, how many years has it taken you to notice this? Of course, it was your "interpretation" of Greenhill's data that required a double hump. So you're the one who has some explaining to do. or insist that it is OK to add up all the random (50/50) correct guesses of all the eleven panelists, good performers' results pulling up the bad ones to get a group "positive" result to his liking? Thus obfuscating what really mattered: that a few did hear and most did not. Yet again, Mr. Mirabel tries to prove the null hypothesis. How many chapters of "Introduction to Statistics" did he get through? Or quote a recognition of gross electrical difference between cables as a "positive Marcus- Ovchain 1,75 db test" It is a chore to have to restate the same every few months. And just as productive. Then spare us. bob |
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Why do the anti-ABX folks not deliver?
(Audio Guy) wrote in message news:92T%a.171246$o%2.76310@sccrnsc02...
In article fLP%a.137308$cF.38433@rwcrnsc53, (ludovic mirabel) writes: For the last two years I have been repeating that 1) there are differences between components 2) they are audible to some and not audible to others 3) explicitly, in those words and within te last two weeks I repeated (see the (Why DBTs in audio do not..." July 25 posting) that talented or supertrained listeners such as Pinkerton, Krueger, Clark and Greenhill's "golden ear" will still hear them even when ABxing. 4) that reporting as the end-outcome the majority vote of ABX untrained/untalented and ignoring the capable minority who DO hear-exactly the way Greenhill had done (see Marcus quotes)is a perversion of "testing". Pleas explain why this is a "perversion of "testing"". If there are those who can hear differences using ABX and those who do not, why jump to the conclusion that ABX is hampering those who do not? Why wouldn't the logical explanation be that they just can't hear the differences at all? My prose makes you suffer- I won't inflict it on you. Just read the postings over the last two weeks Now Marcus should know all that. He's been arguing for the last two years against myself and Harry Lavo that Greenhill was perfectly right basing his conclusions on the incapable majority and ignoring what Greenhill himself (rather unusually- the ABXing proctors, who followed him, did not copy his honesty)- called a true "golden ear". You keep ignoring the statistical evidence, without a retest it is impossible to know if if there was a true "golden ear" since the results fit within the curve of possible random guesses. Take it up with Greenhill who is well, alive and writing for the "Stereophile. Match your knowledge of statistics against his. I'm only quoting . For the rest of your missive all I can say is "Poor Marcus- with friends like these....". Ludovic Mirabel Today Marcus chooses to attribute to me the exact opposite of what I argued for: a strange assertion that NO ONE "..can distinguish the audio componments using ABX" But then another possibility occurs. Maybe he is not just bent on winning any which way. Maybe he really *believes* the nonsense he is voicing loudly.. Look who's talking, if the shoe fits... This is not the first time either- he's a repeater. Look at the clever-clever but very transparent way he goes about obfuscating the sense of clear and *emphatic* Greenhill's own words. Again, look who's talking... Surely he couldn't believe that he convinces anyone ...unless he managed to convince himself first. Perhaps he is no Macchiavelli. Perhaps he is simply unable to grasp the meaning of a simple text. This possibility would be in keeping with his stance throughout. You keep describimg your own approach and misunderstandings of the subject matter, not Bob's. His sending people who know more about the subject than he does for refresher courses he did so send me, Harry Lavo and some others), I'm not sure who else you are referring to here but yourself and Harry, but you have shown you have little understanding of the topic. his preaching about what "we" (ie. Marcus) say is the truth about everything under the sun: electronics, psychometrics, statistics. When it is quite obvious that eg. he never got beyond the first two chapters of something like "Introduction to statistics for lawyers" and misunderstood those to boot. Again, he has shown a much greater understanding of those topics than you. Would he otherwise talk about statistical "double humps" when discussing a panel of eleven (yes 11) listeners or insist that it is OK to add up all the random (50/50) correct guesses of all the eleven panelists, good performers' results pulling up the bad ones to get a group "positive" result to his liking? Thus obfuscating what really mattered: that a few did hear and most did not. The only one who continues to obfuscate here is you whith your extremee misinterpretations fo statistics. Or quote a recognition of gross electrical difference between cables as a "positive Marcus- Ovchain 1,75 db test" That phrase is your Frankenstein creation, not anyone else's. It is a chore to have to restate the same every few months. And just as productive. Yes, I do wonder why I bother restating myself to counter your overly wordy verbiage that can't seem to get the the point. It is a chore. |
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Why do the anti-ABX folks not deliver?
chung wrote:
Wylie Williams wrote: The problem I have in deciding if I should upgrade my systems's amp is that I only have access to amps that are reviewed by magazines as being very fine (Parasound and HALO). As I read it on RAHE these magazine reviews may not be at all reliable. I may not have been unfortunate enough to have ever had a well designed amp in my system, and even if I were to borrow a few I have no idea that they would be amps from the limited group of "competent designs". I have listened mostly to Parasound and HALO, with side trips to YBA, and HK Citation 1, but RAHE experts tell me that there is no way to find out if these are good guys or bad guys. The only way is to gather a bunch of amps and do ABX tests for myself. But I don't even know the identity of amps can be used as reference example of good amps. RAHE tells me they exist, but nobody can make their fingers hit those keys to name brands and models. This leads to a secondary but related point - Given the number of participants who assure the group repeatedly that they are truly experts, what is most surprising is how little specific information they post. Let me reference you to The Proceedings of the AES 1990 Conference "The Sound of Audio" which has an analysis and reference list to 23 controlled tests of power ampliifers; the March 1997 issue of Audio Magazine; the June 1999 Sound & Vision; the September 1995 issue of Sound & Vision (Canada) for specific details of controlled listening comparisons. Any nunber of people are willing to go into endless detail about why someone else does not really understand DBT, ABX, cables, wires, jitter, how stupid audio designers are. etc. etc. etc., but the one post of yours describing your personal tests of several years ago was the first one that gave specifics. I've listed specifics a number of times. You may be 'new' but specifics are common. Follow www.pcabx.com to the smwtms site results. Naturally it has been questioned. What can explain the absence of helpful specifics on RAHE? Is there a code of "Don't ask - Don't tell"? Wylie Williams You want specifics: in 1995 I publlished results in the Canadian Sound & Vision where hard-core audiophiles were unable to distiniguish zip cord speaker cable from their audiophile cables in their personal reference systems; I've also witnessed a audio salon owner fail to reliably identify his kilobuck ampliifers from a garden variety integrated amplifier in his personal reference system (not once but twice.) In 1998 I conducted a 'series-tweak' experiment where I asked 10 audio enthusiasts to identify a fully-tweaked system (vacumn tube pre-amp, outboard DAC, Bryston amp, audiophile interconnects and networked audiophile speaker cables, special cable dress with resonance-absorbers) with a definitely Geak system (1976 $99 Heathkit preamp, $200 used-Parasound amp, 16 guage car-audio zip cord speaker cables with a 25-foot length on one channel and 6-feet on the other with the long run wrapped around the power leads for the electronics and junk-box interconnects) and not one was able to reliably tell them apart in single listener sessions. Need MORE details? Was there something that you did not like about your amp? I can tell you how I chose my amp. I was looking for one that can deliver 200W continuously into 8 ohms, and 400W continuously into 4 ohms. I also wanted it to be stable driving into 2 ohms, if not 1 ohm. I wanted it to be solid-state because of reliability and quick power-up, and I wanted to limit the cost to less than $4K in 1990 dollars. I listened to several well-known ones, and I had trouble telling them apart when the levels are matched. OK; finally someone who will admit this. I finally picked the Aragon 4004 Mk2 because (a) it sounded the same as several models a lot more expensive, (b) the layout and the construction looked clean to me, and (c) the specs matched what I need. I have been very happy with the selection. Perfectly reasonable selection criteria. Yes, there might be others that would do the job equally well, I am sure, but once I bought it, I have really not worried about the choice. No problemo .... as the new California Gov might say. In the past, when I had test equipment and huge resistive loads available to me, I also liked to measure amplifiers. I have not checked the Aragon on the bench that thoroughly, though, since I could not locate a 2-ohm load and I am too lazy to build one. Do you have any interesting stories about when you did 'like' to measure amplifiers? |
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Why do the anti-ABX folks not deliver?
"Wylie Williams" wrote in message ...
On Sat, 16 Aug 2003 16:56:43 GMT, "Wylie Williams" wrote: Your project was a large expenditure of time and energy, which many of us are not willing to undertake unless we are in the market for a component. But as a hobbist I would like to regularly read about the results of such tests in hopes that something truly better turned up in the world of high end. It makes me wonder why reveiwers for the audiophile magazines don't do ABX testing. If it were true that "all amps sound alike" reviewers would not want to publicize that fact because they are in the business of writing about differences. But there are diffrences so that reasoning is out, and their jobs are secure. "Stewart Pinkerton" replied in message ... Unfortunately, while there are still many poorly designed amps on sale at very high prices (almost all of the single-ended triode variety), there is also a huge raft of very competent designs which I am reasonably sure would *not* show audible differences in a level-matched DBT. This would rather cut the rug from under such 'golden eared' reviewers as Martin Colloms and his bizarre points scoring system, so you're unlikely to see DBTs in the audio ragazines any time soon. The problem I have in deciding if I should upgrade my systems's amp is that I only have access to amps that are reviewed by magazines as being very fine (Parasound and HALO). As I read it on RAHE these magazine reviews may not be at all reliable. I may not have been unfortunate enough to have ever had a well designed amp in my system, and even if I were to borrow a few I have no idea that they would be amps from the limited group of "competent designs". I have listened mostly to Parasound and HALO, with side trips to YBA, and HK Citation 1, but RAHE experts tell me that there is no way to find out if these are good guys or bad guys. The only way is to gather a bunch of amps and do ABX tests for myself. But I don't even know the identity of amps can be used as reference example of good amps. RAHE tells me they exist, but nobody can make their fingers hit those keys to name brands and models. This leads to a secondary but related point - Given the number of participants who assure the group repeatedly that they are truly experts, what is most surprising is how little specific information they post. Any nunber of people are willing to go into endless detail about why someone else does not really understand DBT, ABX, cables, wires, jitter, how stupid audio designers are. etc. etc. etc., but the one post of yours describing your personal tests of several years ago was the first one that gave specifics. Naturally it has been questioned. What can explain the absence of helpful specifics on RAHE? Is there a code of "Don't ask - Don't tell"? Wylie Williams I feel your pain, Wylie, but do you know how many amps there are? I'd guess most folks here bought their amps some time ago, and are not constantly upgrading, for obvious reasons. So there's not much reason for them to be constantly testing new amps. Fortunately, there's a way for you to get a handle on all of this--do some ABX tests comparing the amps you have available to you. If you keep getting negative results, then you can pretty much assume that you can't hear a difference between them, at least in the system in which you'll be using them. (And if they're all the same, they're almost certainly all "competent." After all, what would be the odds that a bunch of incompetent amps would all be incompetent in the same way?) If you get any positive results, well, report back here, and perhaps some of the experts can offer an explanation as to why, and which amp might be the underperforming one. bob |
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Why do the anti-ABX folks not deliver?
Nousaine wrote:
In the past, when I had test equipment and huge resistive loads available to me, I also liked to measure amplifiers. I have not checked the Aragon on the bench that thoroughly, though, since I could not locate a 2-ohm load and I am too lazy to build one. Do you have any interesting stories about when you did 'like' to measure amplifiers? One unusual amp that I measured was the Carver receiver which had a "magnetic" amplifier. When driving an 8 ohm load continuously at near spec'ed power, the amp will make a fairly loud noise as if a transformer was humming. It was pretty unnerving. IIRC, it did not meet its THD specs. Also, I noticed a pretty bad design error on that receiver. If you have a line level source connected to one of its inputs, and the receiver is powered off while that source is active, the analog switch at the receiver input will clamp that drive signal to about a diode drop of ground. This causes tremendous distortion as well as dc shifts at the output of the driving source which could be driving another receiver/amp. |
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Why do the anti-ABX folks not deliver?
(Stewart Pinkerton)
wrote: On 15 Aug 2003 21:30:55 GMT, (randyb) wrote: (Stewart Pinkerton) wrote in message ... On 15 Aug 2003 14:34:45 GMT, (Nousaine) wrote: My point isn't that every amplifier used in every test hasn't been replicated but that many tests had been published but none of those had results that matched those claimed by Stewart. That's OK; but until his results become documented and are replicated they remain anecdotal. So, how soon can you get here? :-) Ok, I have not been around this group that long, but I am pretty well on the objective side of the fence. My question is that both you, Stewart and Tom Nousaine seem to be objective, but apparently Stewart has come up with a different set of results in a DBT. Could you both elaborate without me searching the archives as to what was tested and the results. Thanks. We were burgled (grrr!) and I had to replace my TV sound system, so I was in the market for a new amplifier. I had just purchased my Apogee Duetta Signatures and Krell KSA-50mkII amp, so I had a good 'reference' amp and a tough speaker load with exceptional clarity and 'openness'. I had also settled on Tannoy 633 speakers for the TV system (in my view, you buy speakers you like, then you buy an amp which can drive them). I assembled a 4-pole switch-box with relay connections, and a 3-way switch enabling me to select A, B or 'X', with X being set by a hidden toggle switch on the relay box. The 'X' switch had a central 'off' position, so that each reset used two clicks of the switch. I also made up a 4-channel attenuator, enabling me to set the gains of each channel of a pair of stereo amps to be matched within +/- 0.1dB. Next, I entered negotiations with some local hi-fi dealers, and over a period of a couple of weeks or so, I was able to borrow a pair of Denon POA6600 monoblocks, a Hafler XL600, an Arcam Xeta One, a Yamaha 2090, a Yamaha AX-570, A Rega Elex, A Musical Fidelity E600, an Audiolab 8000A, and an Audiolab 8000P. I set up a series of 20 trials of each amp, with my wife doing the switching. She flipped a coin 20 times, and noted on a score sheet whether it was heads or tails. She set the 'X' switch to A for heads and B for tails after each test. I'd satisfy myself as to the identity of X and mark it on a score sheet, my wife would enter the room, reset the identity of 'X' and leave the room while I conducted the next test. To we terminally tweaky/freaky we'd have you leave the room when the switch was made as well. 20 trials is a good number. The end result was that the Denons (fave rave reviews in all the rags at the time) and the Rega were instantly tossed for rough treble, the MF was instantly tossed for a 'veiled' sound with recessed treble, the Yamaha 2090 and Arcam were tossed for slightly bright treble, while the remaining amps were too close to call. So you have results for all these comparisons? The next obvious question is what was the reference for any given device? Krell? What was the reference "toss'' point for the *******, as it were But it seems that you didn't confirm frequency response into the load either. Not a critical issue but one that I generally care for by checking level match at 100, 1000 and 10,000 Hz. Retesting of the Audiolab 8000A revealed a *slight* veiling of the sound, but it just crept into the '16 out of 20' target score, while the Yamaha AX-570, the cheapest amp on test, was a real surprise. I got 15/20 correct, but only revealed by a slight treble brightness on viloin solos. The Hafler and the Audiolab 8000P were sonically identical to the Krell, no better than 12/20 on original or retest. The Hafler, probably the best all-rounder as it was very powerful as well as quiet and sonically impeccable, was rejected on the grounds of its horrendously noisy cooling fan, This is a REAL reason for rejection and needs no corollary tests. But if it was sonically impeccable (I would guess that would be transparent to whatever amplifier which was the comparative reference?) and could be placed in a sealed cabinet or adjacent room it would then be acceptable. leaving the Audiolab 8000P as the 'winner'. Interesting that a sonically impeccable product gets rejected for having a noisy fan Good reason. Better than most. Truth to tell, on the Tannoy speakers I couldn't hear any significant deterioration with the AX-570, but I liked the compact size and 'less is more' approach of the Audiolab, so I stumped up the extra, and it's still serving me well after about 8 years, as is the venerable Krell. I should perhaps mention that I'd actually traded in an older 8000P against the Krell when I bought the Duettas, as the Audiolab got *very* hot after playing some heavy rock music through these insensitive 3-ohm monsters. The Krell didn't put out any more power, but being designed to play continuously into 1 one-ohm load, it wasn't at all bothered about driving the Apogees. As a bizarre aside to the above, I published these test results just a few weeks before the notorious 'Sunshine Trials', where a very vocal (sadly now deceased) 'audiophile' dealer failed to distinguish his favourite exotic Pass Labs Aleph 1.2 monoblocs from an old integrated Yamaha amp (an A-700, IIRC), on his own reference sound system. Steve Maki and Tom Nousaine proctored this test, and Tom was later accused of bringing in the Yamaha as a 'ringer', in view of the exceptional performance of the AX-570 in my own tests. Obviously a gross cheat, eh, sneaking in a good-sounding $500 integrated amp to beat up a $12,000 pair of 'designer label' power amps! -- Stewart Pinkerton | Music is Art - Audio is Engineering I have a bunch of "ringers"! At most price levels and even ages. |
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Why do the anti-ABX folks not deliver?
(randyb) wrote:
(Stewart Pinkerton) wrote in message ... On 15 Aug 2003 14:34:45 GMT, (Nousaine) wrote: My point isn't that every amplifier used in every test hasn't been replicated but that many tests had been published but none of those had results that matched those claimed by Stewart. That's OK; but until his results become documented and are replicated they remain anecdotal. So, how soon can you get here? :-) Ok, I have not been around this group that long, but I am pretty well on the objective side of the fence. My question is that both you, Stewart and Tom Nousaine seem to be objective, but apparently Stewart has come up with a different set of results in a DBT. Could you both elaborate without me searching the archives as to what was tested and the results. Thanks. Stewart has posted results that have not been corroborated by the other couple dozen published controlled listening tests of power amplifiers. There are a couple reasons that his results may not be extrapolatable. He used a speaker load that is not widely distributed in the populace and he employed a family member as proctor. Neither of those conditions necessarily denote contamination but I don't consider the results as more than anecdotal only because no other source has replicated them. Doesn't mean they are wrong but they remain un-duplicated. That's where we are. But one should also note that if you fully accept his data and analysis it tends to confirm that even IF there is an 'amp' sound it's price invariant. So you don't pad your results by "buying-up" and the features of the product are likely to be more important to purchase decisions as sound quality. |
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Why do the anti-ABX folks not deliver?
On 17 Aug 2003 21:42:27 GMT, "Wylie Williams"
wrote: I have listened mostly to Parasound and HALO, with side trips to YBA, and HK Citation 1, but RAHE experts tell me that there is no way to find out if these are good guys or bad guys. I'd award them white hats, although avoid the YBA 'blue laser' CD players like the plague! The only way is to gather a bunch of amps and do ABX tests for myself. But I don't even know the identity of amps can be used as reference example of good amps. RAHE tells me they exist, but nobody can make their fingers hit those keys to name brands and models. As you should be aware, I have already stated that I used an old Krell KSA50 mkII as a reference, and found that the Hafler XL-600 (that would also include the XL-280) and Audiolab 8000P were sonically identical to it, even on a very tough speaker load. You could no doubt also include the Yamaha AX-592, the Roksan Caspian, and the Meridian 551. I am relianbly informed by an impeccable source who won't be drawn into 'naming names' for professional reasons, that the Hafler Transnova series is also of impeccable sound quality. Designing a top-class 60-100 watt amp ain't rocket science in the 21st Century! -- Stewart Pinkerton | Music is Art - Audio is Engineering |
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Why do the anti-ABX folks not deliver?
On 18 Aug 2003 14:23:47 GMT, (Stewart Pinkerton)
wrote: On Sun, 17 Aug 2003 18:24:11 GMT, (ludovic mirabel) wrote: For the last two years I have been repeating that 1) there are differences between components 2) they are audible to some and not audible to others 3) explicitly, in those words and within te last two weeks I repeated (see the (Why DBTs in audio do not..." July 25 posting) that talented or supertrained listeners such as Pinkerton, Krueger, Clark and Greenhill's "golden ear" will still hear them even when ABxing. I am neither a talented nor a super-trained listener (whatever these expressions are supposed to mean). I'm simply an experienced audiophile, and one who's discovered (the hard way!) that *sighted* listening is useless for distinguishing subtle sonic differences. Far from Ludovic's risible claim that ABX somehow 'desensitises' the ear, I've found that it is a much *more* sensitive test for subtle but *real* sonic difference, than anything else I've tried in forty years of audiophilia. Unfortunately for Ludovic, there is *no* test which will reliably and repeatably show sonic differences among 'audiophile' cables, because they simply do not exist. Stewart. The claim that blind testing desensitises the listener is easily tested and disposed of. Simply organise an apparently sighted test, in which the components are apparently swapped visibly, but which in fact are really swapped to a proper blind protocol. The subject now has none of the psychological pressures of a blind test, and should identify with no problem that the differences in sound do not correlate with the swapped components. Of course, there is always the chance that the subject would simply identify the better sound in accordance with what he believed he was seeing - but that wouldn't happen,now would it? d _____________________________ http://www.pearce.uk.com |
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Why do the anti-ABX folks not deliver?
Tom said
Please. I accept any and all "evidence." Stewart's experiments have not been documented nor have they been replicated. The latter isn't his responsibility. The former is. I said The tests in the reports you sent me haven't been replicated either. Tom said Actualy they were all replications of each other I said No they weren't. The equipment, the rooms and the protocol were different in each test. They certianly weren't replications fo each other. Tom said My point isn't that every amplifier used in every test hasn't been replicated but that many tests had been published but none of those had results that matched those claimed by Stewart. I said Well. there goes the claim that no test produced an audible difference. If all the tests in question have accurately reported the equipment, room and sound sources used then they are all replicable. I think Stewert's tests fall under that criteria. Tom said That's OK; but until his results become documented and are replicated they remain anecdotal. I said Sorry but this new criteria of tests having to be "replicated" to be more than anecdotal is nonsense. You can make your own rules of evidence up as you go along but you won't have any established scientific basis for your claims. As I said before, many long term scientific tests have not been "replicated" but are considered to be good, valid scientific tests. I said Doesn't matter. What matters is if the are replicable. Stewert says he has documented his tests. I see no reason to think he is lying. Tom said Oh for Christsakes' as of 1990 there had been been 2 dozen documented and published bias controlled listening tests of power amplifiers that basicallt showed that any device with flat response that wasn't hampered by operating fault or high output impedance were sonically transparent....so why do we need any more evidence on this matter??????? I said And this emotional outburst has what to do with my post? How many of those tests were "replicated?" If that is the new criteria you are pushing for tests to be valid then it seems you may have very little evidence on the issue at all. that would be cause alone for more testing I would think. If you don't want to test any more then don't. Tom said What is so interesting is that you appear to be willing to accept anything that appears to support your position without scrutiny. Then there is a problem with your perception. Tom said You don't happen to be in the market for a bridge? I said I'm not buying any bridges or your personal rules of evidence. Tom said That's fair enough; but neither you nor any interested party nor Stewart has delivered a smoking gun on amp or wire sound. IF these 'differences' truly existed than there would have been clear verification by now. This is not a new question nor is in soluable. If you always choose not to accept evidence of positive tests on the grounds of "uniqueness" of the results, those results will retain their "uniqueness" every time they are presented in a new test. Discounting any test on the grounds of the results is very unscientific. That is a choice you have made. Not me. Tom said You are reduced to 'searching' for evidence, any evidence, that seems to support your position. But you just can't seem to find it and are reduced to championing anecdotes that look attractive to you. Nope. I haven't rejected any test on the grounds that the results were unexpected or unique. That is what you are doing. The fact of the matter is the question is usually to broad and black and white. When one asks the broad question "do all amplifiers sound the same?" There are lots of variables beyond the amps in this question. Good fishing. I see you already have your big fish story. |
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Why do the anti-ABX folks not deliver?
(ludovic mirabel) wrote:
(Nousaine) wrote in message t.net... (S888Wheel)wrote: ..snips....... Please. I accept any and all "evidence." Stewart's experiments have not been documented nor have they been replicated. The latter isn't his responsibility. The former is. The tests in the reports you sent me haven't been replicated either. Doesn't matter. What matters is if the are replicable. Stewert says he has documented his tests. I see no reason to think he is lying. Oh for Christsakes' as of 1990 there had been been 2 dozen documented and published bias controlled listening tests of power amplifiers that basicallt showed that any device with flat response that wasn't hampered by operating fault or high output impedance were sonically transparent....so why do we need any more evidence on this matter??????? I reviewed two extensive relevant bibliographies published in RAHE by Mtry Craft and Klaus Rampelman. There was one only (1) published panel ABX "listening test" in the Stereo Review 1982- of course with a negative result. Mr' Krueger and his two supertrained ABX codevelopers published one, too supposedly positive but hardly representative of the average audiophile crowd. If you have "2 dozen" please give references (Mag, author, year, month, page) to a few of them to begin with. You surely are too responsible to join those who said one ane and all that they had "many" , "numerous" and when pressed against the wall kept silent. As for Oakland comparisons of 10 watt DIY Heathkit against 400 watt Dynaco surely you'll not bring up that one again.( you did once) It was funny ha ha "positive" anyway. They could tell the difference, believe it or not. Ludovic Mirabel If you obtain a copy of the Proceedings from the AES 1990 Conference "The Sounf of Audio" you'll find my paper which provides a listing of 23 blind tests of power amplifiers that had been published prior to that time. |
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Why do the anti-ABX folks not deliver?
In article 7dX%a.173729$o%2.82204@sccrnsc02,
(ludovic mirabel) writes: (Audio Guy) wrote in message news:92T%a.171246$o%2.76310@sccrnsc02... In article fLP%a.137308$cF.38433@rwcrnsc53, (ludovic mirabel) writes: For the last two years I have been repeating that 1) there are differences between components 2) they are audible to some and not audible to others 3) explicitly, in those words and within te last two weeks I repeated (see the (Why DBTs in audio do not..." July 25 posting) that talented or supertrained listeners such as Pinkerton, Krueger, Clark and Greenhill's "golden ear" will still hear them even when ABxing. 4) that reporting as the end-outcome the majority vote of ABX untrained/untalented and ignoring the capable minority who DO hear-exactly the way Greenhill had done (see Marcus quotes)is a perversion of "testing". Pleas explain why this is a "perversion of "testing"". If there are those who can hear differences using ABX and those who do not, why jump to the conclusion that ABX is hampering those who do not? Why wouldn't the logical explanation be that they just can't hear the differences at all? My prose makes you suffer- I won't inflict it on you. Just read the postings over the last two weeks I have, and I have yet to find any useful explanations or any shred of understanding of the topic at all in any of them, while it is obvious you have decided to avoid responding to quite few of mine which explain quite well how and where you are mistaken in your often excessive "prose". Now Marcus should know all that. He's been arguing for the last two years against myself and Harry Lavo that Greenhill was perfectly right basing his conclusions on the incapable majority and ignoring what Greenhill himself (rather unusually- the ABXing proctors, who followed him, did not copy his honesty)- called a true "golden ear". You keep ignoring the statistical evidence, without a retest it is impossible to know if if there was a true "golden ear" since the results fit within the curve of possible random guesses. Take it up with Greenhill who is well, alive and writing for the "Stereophile. Match your knowledge of statistics against his. I'm only quoting . Bob has demonstrated quite well on his own how your "interpretations" of Greenhill's comments are misinterpretations. For the rest of your missive all I can say is "Poor Marcus- with friends like these....". Let's keep such personal comments out of the group, OK? |
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Why do the anti-ABX folks not deliver?
S888Wheel wrote:
Tom said Please. I accept any and all "evidence." Stewart's experiments have not been documented nor have they been replicated. The latter isn't his responsibility. The former is. I said The tests in the reports you sent me haven't been replicated either. Tom said Actualy they were all replications of each other I said You know, you probably don't need to do this 'I said/Other person said' stuff. Most if not all newsreaders audtomatically apply some sort of distingishing marks for nested quotes. Nor do you have to quote the entire exchange just to respond to a few lines of it near the end. -- -S. |
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Why do the anti-ABX folks not deliver?
(Nousaine) wrote in message ...
chung wrote: ..all snipped... Thanks for the feedback. Fun stuff; unless you bought one, I guess. I appreciate all the information. I believe that while the results of Tom's studies may be subject to debate, my mind is made up-the burden of proof is on the side that says they need their eyes to hear differences. Not to say that differences may not exist, just that I am not going to take someone's word for it because he/she says it is so. Why should I? |
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Why do the anti-ABX folks not deliver?
Don Pearce wrote in message ...
On 18 Aug 2003 14:23:47 GMT, (Stewart Pinkerton) wrote: On Sun, 17 Aug 2003 18:24:11 GMT, (ludovic mirabel) wrote: For the last two years I have been repeating that 1) there are differences between components 2) they are audible to some and not audible to others 3) explicitly, in those words and within te last two weeks I repeated (see the (Why DBTs in audio do not..." July 25 posting) that talented or supertrained listeners such as Pinkerton, Krueger, Clark and Greenhill's "golden ear" will still hear them even when ABxing. I am neither a talented nor a super-trained listener (whatever these expressions are supposed to mean). I'm simply an experienced audiophile, and one who's discovered (the hard way!) that *sighted* listening is useless for distinguishing subtle sonic differences. Far from Ludovic's risible claim that ABX somehow 'desensitises' the ear, I've found that it is a much *more* sensitive test for subtle but *real* sonic difference, than anything else I've tried in forty years of audiophilia. Unfortunately for Ludovic, there is *no* test which will reliably and repeatably show sonic differences among 'audiophile' cables, because they simply do not exist. Stewart. The claim that blind testing desensitises the listener is easily tested and disposed of. Simply organise an apparently sighted test, in which the components are apparently swapped visibly, but which in fact are really swapped to a proper blind protocol. The subject now has none of the psychological pressures of a blind test, and should identify with no problem that the differences in sound do not correlate with the swapped components. Of course, there is always the chance that the subject would simply identify the better sound in accordance with what he believed he was seeing - but that wouldn't happen,now would it? http://www.pearce.uk.com Mr. Pearce, I do not know who "claims that blind tests desensitise the listener". It certainly is not myself. Since I do not expect you to read and recall all I had ever said let me assure you that I always maintained that it would be against common sense to deny that sighted bias exists. It certainly is a very powerful factor in this North-American setting. I believe also that some are more affected by it than the others but that it is a sensible precaution for everyone to at least have the brand names covered. All I say is that the ABX protocol, specifically, MAY BE a hurdle for many. I listed my rasons many times- the main one being that the panel listening tests to whatever under the audio sun result in a negastive outcome by a thumping majority. I proposed a slightly different "test"= in quotation marks because I see no reason to believe that the individual perceptions of the audio component differences can be "tested" by one universally acceptable method. No more than wines, pianos, violins, or human voices. Using B&W or H-K facilities collect an average audiophile panel and get them to ABX music reproduced by dfferent, reputable full range speakers. My guess is that you'd get a "No difference " majority verdict. And speakers do sound different . Don't they? Ludovic Mirabel |
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Why do the anti-ABX folks not deliver?
(Stewart Pinkerton) wrote in message ...
On Sun, 17 Aug 2003 18:24:11 GMT, (ludovic mirabel) wrote: For the last two years I have been repeating that 1) there are differences between components 2) they are audible to some and not audible to others 3) explicitly, in those words and within te last two weeks I repeated (see the (Why DBTs in audio do not..." July 25 posting) that talented or supertrained listeners such as Pinkerton, Krueger, Clark and Greenhill's "golden ear" will still hear them even when ABxing. I am neither a talented nor a super-trained listener (whatever these expressions are supposed to mean). I'm simply an experienced audiophile, and one who's discovered (the hard way!) that *sighted* listening is useless for distinguishing subtle sonic differences. Far from Ludovic's risible claim that ABX somehow 'desensitises' the ear, I've found that it is a much *more* sensitive test for subtle but *real* sonic difference, than anything else I've tried in forty years of audiophilia. Unfortunately for Ludovic, there is *no* test which will reliably and repeatably show sonic differences among 'audiophile' cables, because they simply do not exist. Sorry for trying too hard to be nice. I accept it: you're just an "experienced audiophile" like any other participant in "Stereo Review" amp. listening test most of whom (but not all) could not hear any differences between the amps they listened to and just like another simple "experienced audiophile " Nousaine whom you can not convince that any comparable amplifiers whatsoever could EVER sound different and just like that other simple "experienced audiophile" Krueger who heard once-Lord knows what he can or can not hear these days- differences between amplifiers that were not on your approved listing. Of course- if only all of them had your room and your Krell and your, thick at the waist, Apogees! No doubt they'd see the light. As for your favourite topics "cables" and "tests" I understand that you decreed that there must be a "test" somewhere out there, and you also decided what constitutes a "test". Correct me if I'm wrong, so far it is ABX or its variant. You certainly have a fatwa out about my favourite anti-bias protocol left-right with random changes. Anything else you'd accept in your "test" canon? For that matter any other audio components that differ other than the amps.? Ludovic Mirabel |
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Why do the anti-ABX folks not deliver?
(Audio Guy) wrote in message news:G680b.182959$uu5.34042@sccrnsc04...
You keep ignoring the statistical evidence, without a retest it is impossible to know if if there was a true "golden ear" since the results fit within the curve of possible random guesses. I answered: Take it up with Greenhill who is well, alive and writing for the "Stereophile. Match your knowledge of statistics against his. I'm only quoting . He commented: Bob has demonstrated quite well on his own how your "interpretations" of Greenhill's comments are misinterpretations. So let's have no interpreting. Just poor Greenhill's own words, word for word and literally and Marcus own words, word for word and literally. Marcus first: Anyone tempted to take Mirabel's assertion here at face value should consult the original article and read for himself that Greenhill said no such thing. bob This is what Greenhill said reporting the outcome of his cable comparison test: ("The Stereo Review, August 1982): "Final significant conclusion one can draw is that at least one genuine "golden ear" exists. Obviously certain listeners whether through talent, training or experience can hear small differences between components" Further Mr. A.Guy reproaches me: I have, and I have yet to find any useful explanations or any shred of understanding of the topic at all in any of them, while it is obvious you have decided to avoid responding to quite few of mine which explain quite well how and where you are mistaken in your often excessive "prose". Here follows a collection of those exposures of my mistakes as presented by Mr. A. Guy in his previous postings: "Again, look who's talking..." "Look who's talking, if the shoe fits..." "...but you have shown you have little understanding of the topic." "Again, he has shown a much greater understanding of those topics than You" "That phrase is your Frankenstein creation, not anyone else's." "Yes, I do wonder why I bother restating myself to counter your overly wordy verbiage that can't seem to get the the point. It is a chore." Mr. A. Guy surely you did not expect little me to cope with the arguments of such conclusive pertinence and brilliancy. You forgot to say that I'm cross-eyed, hump-backed and a failure with ladies. But you added a final touch of humour: " Let's keep such personal comments out of the group, OK?" Ludovic Mirabel In article 7dX%a.173729$o%2.82204@sccrnsc02, (ludovic mirabel) writes: (Audio Guy) wrote in message news:92T%a.171246$o%2.76310@sccrnsc02... In article fLP%a.137308$cF.38433@rwcrnsc53, (ludovic mirabel) writes: For the last two years I have been repeating that 1) there are differences between components 2) they are audible to some and not audible to others 3) explicitly, in those words and within te last two weeks I repeated (see the (Why DBTs in audio do not..." July 25 posting) that talented or supertrained listeners such as Pinkerton, Krueger, Clark and Greenhill's "golden ear" will still hear them even when ABxing. 4) that reporting as the end-outcome the majority vote of ABX untrained/untalented and ignoring the capable minority who DO hear-exactly the way Greenhill had done (see Marcus quotes)is a perversion of "testing". Pleas explain why this is a "perversion of "testing"". If there are those who can hear differences using ABX and those who do not, why jump to the conclusion that ABX is hampering those who do not? Why wouldn't the logical explanation be that they just can't hear the differences at all? My prose makes you suffer- I won't inflict it on you. Just read the postings over the last two weeks I have, and I have yet to find any useful explanations or any shred of understanding of the topic at all in any of them, while it is obvious you have decided to avoid responding to quite few of mine which explain quite well how and where you are mistaken in your often excessive "prose". Now Marcus should know all that. He's been arguing for the last two years against myself and Harry Lavo that Greenhill was perfectly right basing his conclusions on the incapable majority and ignoring what Greenhill himself (rather unusually- the ABXing proctors, who followed him, did not copy his honesty)- called a true "golden ear". You keep ignoring the statistical evidence, without a retest it is impossible to know if if there was a true "golden ear" since the results fit within the curve of possible random guesses. Take it up with Greenhill who is well, alive and writing for the "Stereophile. Match your knowledge of statistics against his. I'm only quoting . Bob has demonstrated quite well on his own how your "interpretations" of Greenhill's comments are misinterpretations. |
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