For the record, this is the situation about my wire 'measurement'. I still measure DIFFERENCES in shielded cables with my test setup. I doubt, at this time, that it is due to distortion in the center wire, itself. This was my original hypothesis, due to the fact that Dr. Vandenhul had measured wire distortion with a different test set-up. However, on further investigation of what Vandenhul had measured, he was operating at a much lower operating level than I can get my equipment to operate. I can also see differences between clean and dirty contacts, and the presence of mumetal near the wire.
At this time, however, I don't know where the distortion is coming from, and Steve Eddy doesn't either.
I do not promote this test any further, because I have run into a 'dead end' where I can measure differences, but they do not reflect similar measurements of similar cables on other equipment. Are there diodes in wires, etc? Of course there are. Virtually any impurity or oxide should create a barrier of some kind and amount. I don't think, however, that this is the main component of what I am measuring, which is unique and repeatable for a given wire configuration.
At this time, however, I don't know where the distortion is coming from, and Steve Eddy doesn't either.
I do not promote this test any further, because I have run into a 'dead end' where I can measure differences, but they do not reflect similar measurements of similar cables on other equipment. Are there diodes in wires, etc? Of course there are. Virtually any impurity or oxide should create a barrier of some kind and amount. I don't think, however, that this is the main component of what I am measuring, which is unique and repeatable for a given wire configuration.
john curl said:
John, typical you to call him 'Dr Vandenhul'. We always call him Aalt-Jouke or AJ when we talk about or to him. That doesn't seem to diminish HIS accomplishments. A very pleasant, accessible and likeable man, he is.
(BTW his last name is written as 'van den Hul', but I know that the american way is to write it as you do).
Jan Didden
Thanks, Jan, for your input. I just wrote AJ's name quickly, without checking first. He did tell me that he has measured problems of distortion in wires at very low levels, about 20 years ago. This of course, is very important to me, because I still make and use moving coil preamps that work approximately 1000 times lower level than a typical digital or tuner input. Interestingly enough, one of his cables (the only one that I have) has always measured very well in my test, along with a few others. This led me to believe that I was measuring what he was talking about, but my working level is typically 30-70mV, and his measurement was MUCH lower, perhaps 60dB lower, and so I am not emulating his measurement.
Hi,
If we must dot the diodes and cross the cables:
The name should be spelled:
Aalt Jouk van den Hul and yes, Mr. VDH does hold a doctor title...
Flicker noise anyone?
Cheers,😉
If we must dot the diodes and cross the cables:
The name should be spelled:
Aalt Jouk van den Hul and yes, Mr. VDH does hold a doctor title...
Flicker noise anyone?
Cheers,😉
john curl said:
John,
I had the chance to obtain a Fairchild/Electro-Metrics EMC-10, which can measure audio band signals from 0.006uV upwards (yes that's correct!). I am all exited to apply it to opwer supply noise and also cable stuff. Hope to get it next week.
Jan Didden
Re: ABX Testing
Oh for crying out loud, how many times does someone have to spell out to you why the above is absolutely, undeniably, categorically FALSE before you quit regurgitating the same incorrect, old, tired excuses? If a single person can detect a change reliably only 0.5% more often than by chance alone, controlled testing (including possible ABX) can absolutely be used to confirm that ability to a high degree of certainty.
I'll say it again... so many concepts have been so badly butchered in this thread (here statistics, and in Thorsten's post just above the one I pulled the quote from the scientific method once again (clue - observation need not proceed theory)) that it is truly frightening.
You make the case for knowing instead of believing, but the more I read the more I am convinced it is indeed your knowledge that is faulty.
Kuei Yang Wang said:
Oh for crying out loud, how many times does someone have to spell out to you why the above is absolutely, undeniably, categorically FALSE before you quit regurgitating the same incorrect, old, tired excuses? If a single person can detect a change reliably only 0.5% more often than by chance alone, controlled testing (including possible ABX) can absolutely be used to confirm that ability to a high degree of certainty.
I'll say it again... so many concepts have been so badly butchered in this thread (here statistics, and in Thorsten's post just above the one I pulled the quote from the scientific method once again (clue - observation need not proceed theory)) that it is truly frightening.
You make the case for knowing instead of believing, but the more I read the more I am convinced it is indeed your knowledge that is faulty.
Re: Re: ABX Testing
Konnnichiwa,
Absolutely. HOWEVER, if I wish to demonstrate THE PROBABLE ABSENCE a small difference (say 0.22/0.17) to a level of significance of .05 I require a very large sample.
Moreover, if 32 People all find that they can identify a given change to a .2 certainty level the whole group requires to be aggregated and requires to now allow the audibility of the suggested effect. However, if I insist that ALL 32 People show a .05 certainty level I could claim (and thius what is happening quite frequently) that no-one could hear the effect with any significant certainty, while I have in fact data that supports the position that the effect is audible.
For those who have not studied Statistics and wish to get a reasonable idea of the position and why I will continue to insist on it are invited to consult the discussion previously published in Stereophile:
The Highs & Lows of Double-Blind Testing
Do not be alarmed by the source in a subjectivist audio magazine, I feel the discussion presented there is completely fair and allows both sides to represent their positions well. I leave it to the genteele reader to draw their own conclusions. Here just one quote I absolutely love:
"When data are nonsignificant, one scientist may conclude that differences are inaudible, another may conclude that it is wiser to withhold judgment (because, for example, it is always possible that ancillary equipment used in the listening test masked otherwise audible differences), another may decide to issue challenges, and a fourth scientist may decide to have spare ribs for dinner. These four scientists, having decided what interpretation to make when listening data are nonsignificant, may be interested in the probability that their significance test will label data as nonsignificant when differences are audible, forcing them to make that interpretation rather than correctly conclude that differences are audible.
For example:
•Scientist 1 wants to know the risk of concluding that differences are inaudible when differences are, in fact, audible.
•Scientist 2 wants to know the risk that he will withhold judgment when differences are, in fact, audible.
•Scientist 3 wants to know the risk that he will issue challenges when differences are, in fact, audible.
•Scientist 4 is beneath contempt because he is eating spare ribs while I am hungry and writing this damn letter!"
Have fun reading and allow me to rest my case. I'm ahmm.... Hungry, from writing all these darn posts.
Sayonara
Konnnichiwa,
RHosch said:
Absolutely. HOWEVER, if I wish to demonstrate THE PROBABLE ABSENCE a small difference (say 0.22/0.17) to a level of significance of .05 I require a very large sample.
Moreover, if 32 People all find that they can identify a given change to a .2 certainty level the whole group requires to be aggregated and requires to now allow the audibility of the suggested effect. However, if I insist that ALL 32 People show a .05 certainty level I could claim (and thius what is happening quite frequently) that no-one could hear the effect with any significant certainty, while I have in fact data that supports the position that the effect is audible.
For those who have not studied Statistics and wish to get a reasonable idea of the position and why I will continue to insist on it are invited to consult the discussion previously published in Stereophile:
The Highs & Lows of Double-Blind Testing
Do not be alarmed by the source in a subjectivist audio magazine, I feel the discussion presented there is completely fair and allows both sides to represent their positions well. I leave it to the genteele reader to draw their own conclusions. Here just one quote I absolutely love:
"When data are nonsignificant, one scientist may conclude that differences are inaudible, another may conclude that it is wiser to withhold judgment (because, for example, it is always possible that ancillary equipment used in the listening test masked otherwise audible differences), another may decide to issue challenges, and a fourth scientist may decide to have spare ribs for dinner. These four scientists, having decided what interpretation to make when listening data are nonsignificant, may be interested in the probability that their significance test will label data as nonsignificant when differences are audible, forcing them to make that interpretation rather than correctly conclude that differences are audible.
For example:
•Scientist 1 wants to know the risk of concluding that differences are inaudible when differences are, in fact, audible.
•Scientist 2 wants to know the risk that he will withhold judgment when differences are, in fact, audible.
•Scientist 3 wants to know the risk that he will issue challenges when differences are, in fact, audible.
•Scientist 4 is beneath contempt because he is eating spare ribs while I am hungry and writing this damn letter!"
Have fun reading and allow me to rest my case. I'm ahmm.... Hungry, from writing all these darn posts.
Sayonara
Hi,
To recap: Scientist #4 has, with 0.05% certainty, left you some spare ribs.
Cheers...errrrrrrr Guten Appetit, 😉
To recap: Scientist #4 has, with 0.05% certainty, left you some spare ribs.
Cheers...errrrrrrr Guten Appetit, 😉
I dont see how any constructive discussion can continue (or has been ongoing the last 10 pages) .
- No one here has tried the stones
What would You like to discuss, James Randi ?
/
- No one here has tried the stones
What would You like to discuss, James Randi ?
/
Shakti Stone
New poster. I've had the Shakti Stone for about 8 years as well as a pair of the smaller Shakti On-lines. I find the large "stone" to have only one location where it improves the sound noticably; in other locations (in my system) it does nothing or slightly degrades the sound. Not intending to stir up any additional controversy, the Shakti stone is "directional" -- it should be rotated to find the best orientation. I can imagine the sound in the room could become discombobulated (relatively speaking) if several of the stones were strew about indiscriminately. The smaller On-lines, intended for cables and interconnects, did not work for me where suggested, but they do improve the sound on top of the output transformers of my humble Fisher 500C receiver. (The Fisher is not stock, having undergone an upgrade by BWS Consulting some years back, including power supply mods and aircraft-grade Bendix output tubes.) YRMV. 🙂
New poster. I've had the Shakti Stone for about 8 years as well as a pair of the smaller Shakti On-lines. I find the large "stone" to have only one location where it improves the sound noticably; in other locations (in my system) it does nothing or slightly degrades the sound. Not intending to stir up any additional controversy, the Shakti stone is "directional" -- it should be rotated to find the best orientation. I can imagine the sound in the room could become discombobulated (relatively speaking) if several of the stones were strew about indiscriminately. The smaller On-lines, intended for cables and interconnects, did not work for me where suggested, but they do improve the sound on top of the output transformers of my humble Fisher 500C receiver. (The Fisher is not stock, having undergone an upgrade by BWS Consulting some years back, including power supply mods and aircraft-grade Bendix output tubes.) YRMV. 🙂
john curl said:
John,
do you say that you shield the cable under test with mumetal?
Mumetal is a magnetic shield and we use a lot of it to shield photomultipliers from Earth's magnetic field.
New poster. I've had the Shakti Stone for about 8 years as well as a pair of the smaller Shakti On-lines. I find the large "stone" to have only one location where it improves the sound noticably; in other locations (in my system) it does nothing or slightly degrades the sound.
I'm sure you believe that. If you can prove it in a double blind comparison, you might be one million dollars richer.
If you beleive in magic rocks, perhaps you should try some of those wooden frisbees, the Mpingo disks. I guarantee they are at least as effective as the rocks.
I'm sure you believe that. If you can prove it in a double blind comparison, you might be one million dollars richer.
If you beleive in magic rocks, perhaps you should try some of those wooden frisbees, the Mpingo disks. I guarantee they are at least as effective as the rocks.
Citing a refernce to a Sterophile article regarding ABX testing is on a par with popping your radiator cap to check your gasoline level.
The article in question should then be compared to the following:
Comments on "Type 1 and Type 2 Errors in the Statistical Analysis of
Listening Tests" and Author's Replies 674942 bytes (CD aes4)
Author(s): Shanefield, Daniel; Clark, David; Nousaine, Tom; Leventhal, Les
Publication: Volume 35 Number 7/8 pp. 567·572; July 1987
Transformed Binomial Confidence Limits for Listening Tests 468821 bytes (CD
aes5)
Author(s): Burstein, Herman
Publication: Volume 37 Number 5 pp. 363·367; May 1989
Abstract: A simple transformation of classical binomial confidence limits
provides exact confidence limits for the results of a listening test, such
as the popular ABX test. These limits are for the proportion of known
correct responses, as distinguished from guessed correct responses.
Similarly, a point estimate is obtained for the proportion of known correct
responses. The transformed binomial limits differ, often markedly, from
those obtained by the Bayesian method.
Approximation Formulas for Error Risk and Sample Size in ABX Testing 442116
bytes (CD aes4)
Author(s): Burstein, Herman
Publication: Volume 36 Number 11 pp. 879·883; November 1988
Abstract: When sampling from a dichotomous population with an assumed
proportion p of events having a defined characteristic, the binomial
distribution is the appropriate statistical model for accurately
determining: type 1 error risk (symbol); type 2 error risk (symbol); sample
size n based on specified (symbol) and (symbol) and assumptions about p; and
critical c (minimum number of events to satisfy a specified [symbol]). Table
3 in [1] pre;sents such data for a limited number of sample sizes and p
values. To extend the scope of Table 3 to most n and p, we present
approximation formulas of substantial accuracy, based on the normal
distribution as an approximation of the binomial.
If you haven't figured it by now the subjective audio press doen't like ABX because it's bad for sales.
The article in question should then be compared to the following:
Comments on "Type 1 and Type 2 Errors in the Statistical Analysis of
Listening Tests" and Author's Replies 674942 bytes (CD aes4)
Author(s): Shanefield, Daniel; Clark, David; Nousaine, Tom; Leventhal, Les
Publication: Volume 35 Number 7/8 pp. 567·572; July 1987
Transformed Binomial Confidence Limits for Listening Tests 468821 bytes (CD
aes5)
Author(s): Burstein, Herman
Publication: Volume 37 Number 5 pp. 363·367; May 1989
Abstract: A simple transformation of classical binomial confidence limits
provides exact confidence limits for the results of a listening test, such
as the popular ABX test. These limits are for the proportion of known
correct responses, as distinguished from guessed correct responses.
Similarly, a point estimate is obtained for the proportion of known correct
responses. The transformed binomial limits differ, often markedly, from
those obtained by the Bayesian method.
Approximation Formulas for Error Risk and Sample Size in ABX Testing 442116
bytes (CD aes4)
Author(s): Burstein, Herman
Publication: Volume 36 Number 11 pp. 879·883; November 1988
Abstract: When sampling from a dichotomous population with an assumed
proportion p of events having a defined characteristic, the binomial
distribution is the appropriate statistical model for accurately
determining: type 1 error risk (symbol); type 2 error risk (symbol); sample
size n based on specified (symbol) and (symbol) and assumptions about p; and
critical c (minimum number of events to satisfy a specified [symbol]). Table
3 in [1] pre;sents such data for a limited number of sample sizes and p
values. To extend the scope of Table 3 to most n and p, we present
approximation formulas of substantial accuracy, based on the normal
distribution as an approximation of the binomial.
If you haven't figured it by now the subjective audio press doen't like ABX because it's bad for sales.
Arthur-itis said:
Wow, thanks for the tip. Say, have you a peer-reviewed article using appropriate statistical methods showing in fact that the subjective audio press doesn't like blah blah?
john curl said:
Well yeah, given that MuMetal is a high permeability ferromagnetic material and that copper and aluminum are both paramagnetic (actually I think they're both very slightly diamagnetic) and have permeabilities about the same as air.
However unless you're approaching saturation, MuMetal is far more linear than iron and steel.
se
john curl said:
But I know where it's NOT coming from. It's NOT coming from the cables. And if it's not coming from the cables, that leaves your test equipment. Which I couldn't care less about.
se
Based on what I saw, it is not likely to be an intrinsic property of the cables but rather some sort of interaction between them and the test gear. My guess is that John concurs. The difference is metaphysical, admittedly, if you believe that artifacts 120 dB or more down could be audibly significant. That's where John and I part company 😀
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