| panomaniac |
As you may know from reading the “Do speaker cables make a difference?” thread, I submitted a speaker cable test to the James Randi Educational Foundation (JREF).
JREF have put up a $1,000,000 prize for proof of the paranormal and have extended the challenge to include some audio cable claims.
The title of this thread is “The JREF cable challenge test.” But I will be calling my test the “Balanced Bridge Test” to be clearer about how it functions.
Below you can read what I submitted to JREF and their reply. The application allows only “two brief paragraphs” to state your claim. You will find those paragraphs below, as well as the diagrams I submitted. After the JREF reply, I will elaborate on the test, its strengths and weaknesses. All criticisms are welcome.
My submitted claim:
| quote: | Speaker Cable Test
This test will demonstrate that a real difference, both audible and measurable, exists between different types of speaker cables. This test is based on the well established bridge circuit (see below) that is very sensitive to differences in the two branches of the bridge. The illustrations below are the same electrical circuit. The key word to this test is “difference.” Thus only the difference between cables (if any) will be audible in the test speaker.
The demonstration will be conducted with real speakers, real amplifiers and a real musical signal, between non identical speaker wires. To be considered successful the demonstration will have to show an easily audible difference produced by the test speaker. The demonstration will be said to fail if no audible difference is found, or if the difference is one of simple attenuation that can be corrected with a volume control. The demonstration will also be considered to fail if the majority of the people listening determine that the audible difference is too small to matter. |
The James Randi Educational Foundation reply:
| quote: | Your application for the JREF prize has been received today.
You claim that you can demonstrate a difference between the electrical characteristics of different sorts of speaker cables. This is evidently true, since small-gauge and/or cables of inferior materials or poorly connected, will clearly show less satisfactory audio images. We find nothing paranormal in that claim.
Your application is rejected because it does not fall within the parameters of the JREF challenge. |
“Nothing paranormal” Can’t argue with that! But I think they missed the point. I claim to demonstrate the audible differences, not just electrical. And any test or audio signal can be used, even Elvis or ABBA.
The point is to conduct a rigorous test between what should be identical cables, same gauge and same length, with good connections, to find if there is a difference. Cables of different lengths and/or gauges could also be tested.
The test hinges on the difference. If there is one, then a signal will appear between the 2 sides of the balanced bridge. No difference, no signal. Pure and simple. Either there is, or there is not. Using a speaker or headphones across the bridge will allow the difference to be heard, if it exists. The difference could also be measured with voltmeter, oscilloscope, spectrum analyzer, etc. This is the Wheatstone Bridge, a circuit that has been used in measurements since the 1830’s.
Remember, -- all that is measured here is the difference, nothing else. That makes the difference very obvious, if it exists, because the difference is the only thing you will hear or measure.
Cables of different DCR will produce a difference signal in this test, but that can (or should) be ruled out.
If a difference is found, it will not tell you which cable is better. But by extension the test should be able to determine which cable is best, or at least which is of the “highest fidelity.” (More on that later)
There are, of course, difficulties in setting up the test and getting the bridge balanced using real loads, but those can be addressed. If the bridge is out of balance, you’ll know right away, that’s the beauty of the test. =)
I’ll go into more detail in the next post. Thanks for reading all the way down. |
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| SY |
| There's the flaw- you're not dealing with the claims of audibility which often (usually) venture over the paranormal line. No-one disputes that differences may be measurable with the right test setup (after all, they're just R, L, and C), the controversy surrounds claims of audibility between two systems that are not oscillating and have the same frequency response and level within the audio band. |
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| soongsc |
| I quite agree with SY. |
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| macgyver10 |
Hey Panomaniac,
I had to return to comment on this, since I was the one who brought up the JREF prize in the first place.
Your wheatstone application could, potentially, be used to help set up a JREF challenge, but it isn't essentially what the JREF is about.
In fact, it's not even what I was hoping to test either. As many have mentioned, there is no dispute that all cables have characteristic L,C,R values that define their electrical characteristics. There are even cases where these measurable characteristics can cause audible effects (ie, certain amp/load combinations or excessive capacitance cables causing oscillation in amplifiers.)
Engineers, and subjectivists both can agree on these points, and have.
What needs testing is the claims by some that electrially identical (in fact even "similar" would probably suffice) cables can cause audible differences that we can not measure using conventional L,C,R measurements.
For instance, if a OFC copper cable and a Silver cable were shown to have nearly the same values of L, C, R and were placed into a high DF amp/speaker combination, measurements would show them to essentially be identical. However, many "audiophiles" would maintain that the silver cable was far superior for a whole host of pseudoscientific reasons.
So, in a nutshell, if your JREF application where to say "I claim that, under controlled conditions, I can hear differences between speaker cables of different composition that show no measurable electrical differences." you might have a shot at the $1,000,000
So, unlike some have suggested, you haven't "won", because you haven't presented a paranormal (ie irrational) claim. |
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| panomaniac |
| quote: | Originally posted by SY
There's the flaw- you're not dealing with the claims of audibility which often (usually) venture over the paranormal line. |
Can't argue with that. But I'm not claiming paranormal properties for cables. And I don't know any cable seller who is. They may be claiming absurd things for their cables, but the claims are almost always based on science. Bad science, ridiculously bad science sometimes. But science and physics. No cables I've seen claim to be better because of witchcraft, voodoo, the Virgin Mary or space aliens. They claim to be better because of some physical properties of the cable.
So let's forget the paranormal stuff, OK?. That's why my claim was rejectedb y JREF, but it has nothing to do with the validity of balanced bridge test.
| quote: | | No-one disputes that differences may be measurable with the right test setup (after all, they're just R, L, and C), |
Ah, but some do dispute this. At least within "normal" boundaries. I agree that if the R, L and C are vastly different, there will be a noticeable difference in the sound. But many seem to claim that subtle differences in those values will NOT affect the sound.
Lets call them the "Zip Cord Club" (of which I my be a member). "14 gauge Zip Cord is all you need! Anything more is a waste of money! You won't hear a difference." OK, lets see if that is true. Let's test it. The balanced bridge is a good test.
On the one hand there are the cable enthusiasts who claim their cables are better because of better materials - pure copper, special insulation, long crystals, silver wire, etc. Or better because of special construction. Braids, ribbons, helium cores, cotton fibers, etc. And any mix of the above. The cable enthusiasts claim their cables sound better because of what these special qualities do - or don't do. If they are "better", then they are different.
An the other hand the Zip Cord Club claims that all that is nonsense, as long as the cable is of adequate gauge and is not causing amplifier oscillation, no one can hear the difference. Therefore NO difference in the audio domain.
But what if we test two different cables and do find a difference? Why is there a difference? Is it due to the different L, C, R values of the cables? We can test this. Simply add a few passive components to cable A, so that it matches the L C R of cable B. Test again. No difference? It must be the L C R values of the cable that give it its sound. No need to buy expensive cables if we can imitate the sound with a few passive components.
What if there is still a difference when the two cables have identical L C R values? Then we have to look further for what the difference might be.
The test is not limited to different cables. The same cables can be measured when they are deployed differently. For example, one cable run on the floor, the other on blocks. Is there a difference? You'll know for sure. Either there is or there isn't.
The strength of the balanced bridge test is that it removes the doubt as to whether a difference really exists. If you hear something in the bridge speaker, there is a difference. If you hear nothing, no difference. Simple as that.
EDIT:| quote: | | So, in a nutshell, if your JREF application where to say "I claim that, under controlled conditions, I can hear differences between speaker cables of different composition that show no measurable electrical differences." you might have a shot at the $1,000,000 |
Good point! And I can test for that. Don't know what the results will be, but it will be fun to find out. |
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| macgyver10 |
| quote: | Originally posted by panomaniac
Can't argue with that. But I'm not claiming paranormal properties for cables.
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Neither is anybody else! The Paranormal ability is in the listener, not the cable.
| quote: | Originally posted by panomaniac
Good point! And I can test for that. Don't know what the results will be, but it will be fun to find out.
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The only way to test for the claim that I proposed is double blind LISTENING tests. It's the only way to test the LISTENER that claims to hear what can't be measured.
One way to test the claim is to use two identical cables (use your wheatstone to make sure they are perfectly balanced if you like) but tell the claimant that one of them is cryogenically treated long crystal Silver foil, and the other is 14 guage copper lampcord.
Then tell him to make notes on the "sound" of each cable. Then test him in an ABX situation.
Guaranteed this listener will "hear" a difference when non exists, and not be able to tell the cables apart in a double blind ABX.... |
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| Cloth Ears |
| quote: | Originally posted by panomaniac
The demonstration will be conducted with real speakers, real amplifiers and a real musical signal, between non identical speaker wires. To be considered successful the demonstration will have to show an easily audible difference produced by the test speaker. The demonstration will be said to fail if no audible difference is found, or if the difference is one of simple attenuation that can be corrected with a volume control. The demonstration will also be considered to fail if the majority of the people listening determine that the audible difference is too small to matter. |
Hi Panomaniac,
You've only covered half of the conundrum. For the test to be valid, you also have to have comparisons between identical cables (ie the cable that the person is comparing is actually the same cable), giving the listener(s) the opportunity to "hear a difference" where there is no difference.
There are differences, Nelson Pass demonstrated this in 1980. |
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| panomaniac |
Good points guys, but you've got to start thinking outside the ABX. Stop trying to fool the listener into hearing something that isn't there.
Part of the test setup will certainly have to be testing two identical cables in the balanced bridge to show that no difference can be heard, that the bridge is truly balanced. Only then can the test proceed to different cables.
Of course this doesn't eliminate the idiot who "thinks" he hears something when there is nothing. And I should know, I've been that idiot. We've all wanted to do well on a test, right? But if it can be shown on the O'scope, voltmeter, spectrum analyzer, etc., that there is no voltage difference, then the claim of hearing something can be debunked. If there isn't any current flow thru the bridge speaker, there won't be any sound. Simple.
And the test should be done with a number of people present. If the majority claim to hear nothing, then there is probably nothing there. And that can be confirmed with measurements.
In fact, the hearing part of the test is icing on the cake. It is only there to let you hear the difference that can be more easily measured. And there may be ultra or infrasonic differences measured, but if you can't hear them, why worry? |
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| soongsc |
| quote: | Originally posted by panomaniac
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And the test should be done with a number of people present. If the majority claim to hear nothing, then there is probably nothing there. And that can be confirmed with measurements.
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It just means the majority claim to hear nothing. There still could be something. The same with looking for business opportunities. The majority don't see or react on it.
| quote: | Originally posted by panomaniac
In fact, the hearing part of the test is icing on the cake. It is only there to let you hear the difference that can be more easily measured. And there may be ultra or infrasonic differences measured, but if you can't hear them, why worry? [/B] |
Good point. |
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| SY |
| quote: | | Of course this doesn't eliminate the idiot who "thinks" he hears something when there is nothing. |
A point which cannot be stressed enough- hearing differences that are not there is not a result of idiocy, it's because we have human brains. Millions of years of evolution eliminated phenotypes that wouldn't react without 100% proof that there really was a sabertooth tiger outside the cave.
Our brains are wonderful at finding patterns, and will do so even when the pattern isn't there; running at the mistaken belief that there's a tiger carries very little evolutionary penalty. Not running causes one to be eaten and hence not reproduce. Perhaps this explains our fascination with abstract art and music, but that's going off topic...
Audiophiles want to hear a difference, so without proper controls, they will do so, difference or not. We're not test mikes, we're humans. |
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| Panicos K |
| SY,yes we are not test mics,that's why we listen to music and not series resistors,parallel capacitors and boxes full of all kinds of electrical staff,only to hide any difference. |
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| Panicos K |
| Panomaniac,it seems that not only they have missed the point,but actually they told you you are right.They said gauge size and inferior materials have audible difference,and there is nothing paranormal to this.Ofcource there is nothing paranormal to this.It is perfectly normal,and either you can hear it or not.That's why I think you won. |
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| audio-kraut |
| quote: | | No-one disputes that differences may be measurable with the right test setup |
and the point that a lot here do not seem to get - you will only hear a signal in this setup when the different parameters of the cables will "create" a difference signal that is perceivable.
If no difference signal is audible - even when the measurement shows some signal present - than it clearly shows that those signals are below the threshold of audibility.
And if they are below the threshold of audibility - they are unimportant and any claim as to audibility of cables can be thrown into the trashbin of unsubstantiated claims. |
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| macgyver10 |
| quote: | Originally posted by Panicos K
Panomaniac,it seems that not only they have missed the point,but actually they told you you are right. |
Actually, it appears that you have missed the point. SY summed it up nicely, it's been repeated several times, but you continue to talk about "what you hear" as some kind of evidence of fact.
The point to all of this, is that just as there are visual "illusions" for the same reasons that SY mentioned earlier, there are auditory "illusions" too.
I agree with panomaniac and his conclusions that if differences can't be measured, then they can't be heard...I've been saying that all along.
Other's (you perhaps) still maintain that the measurements are inferior to your own ears. If you claim that, then I say "prove it".
Panomaniac:
All you've done, albeit quite ingeniously, is devise another "scientific" test. This will not convince Panicos K that his ears aren't still superior to your test set up.
As I suggested before, Panicos K is the one who needs to apply for the JREF prize. His claims are testable. Also, one can predict with 100% accuracy that should he fail a test, that he helps to contrive, it will not change his faith that he can hear things we can't measure.
Finally, I will say this (and SY effectively said it too) I BELIEVE that Panicos K hears what he says he hears. I just don't believe there's anything actually there to be heard.
Since the brain is the most influential part of the sense of hearing, only Panicos K knows what his brain is telling him he hears. That doesn't mean that his ears are actually sending those messages to his brain, though. |
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| Panicos K |
Macgyver10.
''......my brain?'' Thank God it's not more and capable to fire hostility even to you.Brain?What brain? |
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| macgyver10 |
| quote: | Originally posted by Panicos K
Macgyver10.
''......my brain?'' Thank God it's not more and capable to fire hostility even to you.Brain?What brain? |
No hostility was ever intended by me. And I'm quite certain you have a very active and formidable brain. Please don't take my comments as some sort of attack. I only use you as an example, because you have been the most vocal with your assertions.
I DO believe you hear what you say you do. I also believe that under the right circumstances I could "hear" exactly the same things. It's a common human trait of hearing; that our minds can construct what isn't there. It has much in common with "placebo effect", and it's very real. It can be removed from the equation, however, with a properly constructed (not necessarily ABX) double blind test.
The scientific tests which uncover the true nature of why some people claim to "hear" what we can not measure will not be in the field of electronics or physics, however.
It will be in the field of biology, and studying the inner workings of the human brain. |
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| Panicos K |
| macgyver10,see my post 886 in''do speaker cables make a difference? |
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| macgyver10 |
| quote: | Originally posted by Panicos K
macgyver10,see my post 886 in''do speaker cables make a difference? |
Yes, I read it. And I don't disagree with it either.
I also don't think it strengthens your position, but rather mine.
Learning to listen for certain things in the music is part of what makes music such an enjoyable hobby. Learning to hear the "small" things that most others don't is also important.
However, hearing things that aren't there is -- spooky, to say the least. |
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| Panicos K |
| macgyver10,many things I learned from this good friend,especially things that had to do with classical music.For example I learned that some instruments must be on the left side of the stage,so my system had no problem as I might have thought with it's L/R balance.I like some classical music but that's not my everyday style so I couldn't know that information.As for the small details you said, it is not something you learn how to hear them. |
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| macgyver10 |
| quote: | Originally posted by Panicos K
As for the small details you said, it is not something you learn how to hear them. |
Of course you can learn how to hear them. The more you understand the music, the more you will hear in it.
There are many things that so called "tin-ears" can't hear, but the "golden-eared" can. Much of this is just a matter of study, and experience. I have no qualm with that.
But if you say you can hear things that just aren't there, for instance -- the "direction" that your speaker cable is connected, then I suggest that you're fooling yourself.
Which brings me to another potential JREF challenge, is there somebody who will claim that their "directional" silver foil high-end "burned-in" speaker cable sounds different when the "direction" is reversed?
Now we're testing the exact same cable, only it's "direction" has changed. Not sure how we'd double blind that.... |
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| Panicos K |
| macgyver10,you said I can hear things that are not there,not me.What I said is that you might not hear things that are there. |
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| macgyver10 |
| quote: | Originally posted by Panicos K
macgyver10,you said I can hear things that are not there,not me.What I said is that you might not hear things that are there. |
Agreed. I'm sure there are things that are there that I can't hear.
However, I'm not claiming that I can hear "everthing". In fact we're in complete agreement with your statement, because I've been saying the exact same thing this whole time. I've said that there are differences so small that they can be measured, but not have any "audible" impact. This is where others will disagree with me, and that's fine too. If you claim to hear such smalll differences you may very well be right. The only way I'll be convinced, however, is through double blind testing.
However, that's not the same as saying you can hear something that can't be measured.
That statement (not necessarily made by you, but definitely made by many) needs to be proven. |
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| KBK |
Firstly, I apologize if this sesms like a rant. YOu think I would know better by now. After 0ver 7000 posts on the AVS forum, I won't go back there and or post. That wagon is full. Sometimes, I think the same is happening here.
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It is the absolute fooishness of man to think that the limit of his senses are the limits of existence. And one man's limits are NOT anothers. We are NOT all created equal.
Too bad, so sad.
I can hear the differnce in the direction of a cable's connection, but depending on the cable and other issues, it can be swamped. It is a subtle thing.
Once again, your ideas on reason are not the limits of reality.
So stop kidding youself, McGuyver. I'm not willing to agure the point. :)
New things start when people pull things out of the darkness, and run them up against the 'established facts' :rolleyes: :rolleyes:...and then run up against people who think that the limits of science are established by known quanta. Only a fool would believe that. Science is an ever evolving, ever changing, ever growing --work in motion.
As new points come along, we have to figure out how to devise new tests, not refute the claim if newness. Any scientist worth a damn knows this, and shouts it from the rooftotps and browbeats anyone who tries to say different.
Tesla was a GOD in science. An absolute GENIUS. How did he fall down?
Just before he started generating power on his 'world grid' he was hoping to establish (using gravity waves), he spoke of the 'intelligent' signals he was recieving from space. He was working for Morgan, who found he wasn't going to beat Marconi, so Morgan dropped him. Morgan wanted the 'first' in wireless. Tesla was and already had been first, but he was actually doing other stuff with Morgan's money. While working with the anomolies recieveing system at Wardencliffe, He came out with the pronouncement of 'signals from space' and was completely ridiculed by the 'accepted' press,and lost his incredible staure, overnight.
Penniless and reputation shot, all in one single year. And he was 100% right, on all counts. One of Tesla's 'faults', was he did not keep records, and did not investigate or 'invent' in known or accepted ways. He simply did it. (I am of a similar bent-I don't have the time or inclination to polarize and shape what I know, just so I can beat my self sensless..against a wall built in someone..who will refuse to listen or understand - no matter how I may couch the given thing)
Tesla was right - there WERE signals from space. We call them Pulsars. Tesla rarely made mistakes, of ANY kind. There are many things that he did, that even today...science (ie, animalistic-emotional 'sceintific establishment'-a bunch of pedantic and bent engineers with zero capacity for imagination) will not accept, true and factual as they may be. (Look at the current political and socio-economic situation in the US right now, for an obvious clue as to humanity's overall incapacity to see basic truths).
Just goes to show you that the ignorance of one, or many, can ruin the accuracy, correctness of statement, or position of another, all due to the emtotional stance of a ignorant person. Down to killing them (killing the messenger), so the respondent can keep his emotional comfort. A psychotically sad state of affairs.
For when we venture into areas we don't know, we bring our emotions into play FIRST. Logic does not rule-at all, no matter how much we may desire such. Realizing that, is the first step in 'going clear'.
And for someone who is purporting to say 'logic' and stating 'without emotion', your postion is -flatly- wrong.
Judgement is the sole providence of fools, it anchors one in the self-lies of one's own past. |
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| macgyver10 |
Ranting, rambling and really not relevant. I could go one by one through your post with rebuttals, but to what end? The emotion is quite evident in your post. It surprises me, how emotion plays on this issue. Quite honestly, I don't really see why emotion is involved. I don't have an emotional involvement in this, except when ad hominem attacks are used to advance weak arguments. Too bad, so sad.
I don't necessarily disagree with much of what you said, but it doesn't apply to what I'm stating.
Do people stumble on ideas that ultimately result in advancement of human knowledge? Sure! no argument. When do we actually know the difference between that idea being madness or having some scientific validity? After we devise a test and prove it. Again, no argument.
That's all I'm stating....you make a claim that you can hear the difference when your speaker cable "direction" is reversed. I say "okay, I don't believe you, but I'm willing to be proven wrong, so prove it" What's your response then?
I have no reason to believe in ghosts, psychics, directionality of speaker cables, Zeus or Santa Claus amongst a whole host of other "ideas". When the evidence proves otherwise, I have no trouble in adopting that as fact. Until then, however, I only have your say-so. That's simply not enough.
My one line rebuttal to your entire post is this: I am more than willing to be proven wrong -- are you? |
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| macgyver10 |
| quote: | Originally posted by KBK
Judgement is the sole providence of fools, it anchors one in the self-lies of one's own past. |
Overlooking the hypocrisy of this statement in the context of your post, it brings up another point that I'm having trouble understanding.
I'm suggesting that while folks like yourself claim to hear things that are not measurable, those things may be constructs of your own mind. In other words, you did "hear" them but there was nothing necessarily external to you causing that.
Why is my theory so easily ignored? How is it any different than your theory that there is something inherent to the cable that is creating something external for you to hear?
I'm being considered a close minded rationalist because my opinion of the origin of what you heard is different than yours?
It seems to me that the conceit lies in the person who can't accept that they, like everyone else, is subject to the same psychoacoustic "phantoms" created in our own minds.
To try and remove the mind from this audio chain, and externalize all sources of "distortion" is akin to an alcoholic blaming the destruction of his life on the alcohol, rather than his uncontrolled desire to drink. |
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| panomaniac |
I think you guys are still too hung up on the poor listener. Let's give him, his ears and his brain a rest.
With the balanced bridge test we are not doing ABX. We will hear ONLY the difference. That makes it sooo much easier because it is so much more obvious.
The web is a visual medium, so let me give you a visual test. Click on the link below. It will take you to a little page I set up with a visual test.
The test shows the same image twice but the bottom image has been altered. There are about 15 alterations. Can you find them? Some are easy, some are very subtle. Some are things that have been removed, others are altered colors.
See what you can find, then click on the bottom image. Voila! Nothing but the difference. Can you see them now? Sure you can! And now it's much easier to spot the differences in the 2 images, because you know what to look for.
Difference Test
The point is, when I show you ONLY the differences, they are obvious. No problem finding them.
If you think it was hard to find the differences in the 2 images, imagine how hard it would be on a video. And you don't get to see both videos at the same time. :eek: That's what you are trying to do with an audio ABX test.
I'll make a little audio difference test and post it here later. |
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| SY |
| Well, that's the test that proved that the Hafler XL280 was the best amp in the world and that the rest of us ought to just pack it in. You might be enlightened by reading some of the reviews of and articles about the XL280; Gordon Holt's was excellent. His summation of the shortcomings of that test method were devastating. |
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| KBK |
My excuse was that I was having a weird afternoon.
I was getting phone calls from the oddest people. Perhaps It was time to make people feel the same about me. Such is life. :xeye:
But I review the post and I still find it, er, my usual over the top and a touch ranty..and possibly to be interpreted as personal and directed in nature....but...accurate enough.
You should see the posts I've made that I'm embarrased about. They leave even me confused.
How's your day going MacGyver? Good I hope.
For me, personally, I wonder why I marched in here, and nailed my proclimation to the door. I've done that one already, more times than I can remember. And somewhere on the AVS forum, they are missing their idiot. They call me up every now and then ask me why they haven't heard from me on the forum. They enjoyed watching the sparks fly. I've had multiple people tell me how they've ruined monitors and keyboards when they choke and spit their food and beer out all over it. I had fun entertaining them, but gladiator sports eventually wear one out.
getting back to the subject at hand, I've been making my own cables and such, for oh, nigh on 25 years. I watched Tara Labs patent or utilize an idea I had for conductor design and geometry -a solid 10 years before they did. But they still don't have my final 'secret weapon!' :devilr:
I was arguing the efficacy of nyquist applied to human hearing ('spacial and harmonic realization' considerations of human hearing require a CLEAN 100khz accurate reconstruction), requiring at least a 225k/20 bit sample rate/depth, in 1991(1993?)..on the 'alt.highend', via bulliten boards. And, arguing cable design and geometry at that time, as well. You would not believe that flack I was taking back then. I came up with a cable design/geometry that is so wicked, it suffers from zero reflection issues. I realized that it had application in space based (or ground based) pulse weapons (and similars), and I have zero desire to aid those *******s, so I left it in the dirt. I since came up with a superior design to that one, but I'm thinking of leaving it in the dirt as well.
I find it quite gratifying that SOMEONE was listening, and Sony used that number as a minimum for their archival work-when the technology became viable. |
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| macgyver10 |
Hey panomaniac,
Your "difference test" is nothing new, and "common mode rejection" is an often used technique used to eliminate distortions in long transmission cables (ie balanced vs. unbalanced). Similar idea at the root. So is the differential input of a standard op-amp.
Even the "isobarik" method of driver loading benefits from reducing non-linearities in a single driver implementation.
The idea is that you can eliminate what is "different" if you mirror the incident signal. In your case, you're using the same basic principle to result in just the difference signal.
However, this has nothing to do with the JREF, and nothing to do with finding out if measured aspects of a cable can be "heard" or not.
You are essential magnifying the differences so that they become noticeable. Much like using an electron microscope allows you to look at dust mites that you can't see with the naked eye.
The question still remains; "what can we hear with the naked ear?"
Before anybody gets all upset that I'm somehow married to a slide rule, and only interested in testing theories that I "believe in", because I have no imagination, or don't think Tesla was the "Jesus" of modern science, I'll just say this one more time:
The test is simple. If you can hear it and claim to do so, then lets devise a test that proves you can. Same equipment you heard it on in the first place, but this time you won't know what the device you're listening to is. I only want to remove the knowledge of what cable you're listening to. It doesn't need to be ABX. Somebody suggest a "better" protocol, if that one is a pariah.
Why is that unreasonable? |
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| macgyver10 |
| quote: | Originally posted by KBK
I came up with a cable design/geometry that is so wicked, it suffers from zero reflection issues. I realized that it had application in space based (or ground based) pulse weapons (and similars), and I have zero desire to aid those *******s, so I left it in the dirt. I since came up with a superior design to that one, but I'm thinking of leaving it in the dirt as well.
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You do realize that if this was being said on the street from your cardboard box and amongst your collection of empty bottles, you'd be elligible for enrollment at the local mental institution?
I understand, now, your choice of hero. The internet is a wonderful place. |
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| panomaniac |
| quote: | Originally posted by SY
Well, that's the test that proved that the Hafler XL280 was the best amp <snip> Gordon Holt's was excellent. His summation of the shortcomings of that test method were devastating. |
Hey Sy.
So someone used a balanced bridge test on amps? That would be tricky, but I can imagine how it could be done, maybe. Would love to read the critique of the test. Got links?
| quote: | Originally posted by macgyver10
Your "difference test" is nothing new |
No, never said it was. In fact I said it's been around since the 1830s. That's pretty old as electrical circuits go. ;)
| quote: | | The idea is that you can eliminate what is "different" if you mirror the incident signal. In your case, you're using the same basic principle to result in just the difference signal. |
Precisely
| quote: | | nothing to do with finding out if measured aspects of a cable can be "heard" or not. |
Huh? What do you think I'm proposing if not to hear the differences? (if they exist)
| quote: | | You are essential magnifying the differences so that they become noticeable. Much like using an electron microscope allows you to look at dust mites that you can't see with the naked eye. |
No, sorry. Completely disagree. Not magnifying at all. Only removing everything BUT the difference, so that you can hear the difference without a doubt. No electron microscope needed. But if you painted those dust mites with phosphorescent paint, then turn out the light and shine a black light on them - we would sure see them! No microscopes needed.
Haven't you ever seen all the lint on your shirt that shows up under ultraviolet light? You're claiming the lint isn't there, or that no one can see it in normal light? There are a lot of women who would argue with you over that one.
Did you look at my visual test? Are the difference so tiny that you needed a microscope to see them? No. Did I enlarge the differences? No. Just showed you the differences that actually exist.
| quote: | | The question still remains; "what can we hear with the naked ear?" |
This test will tell you. If you can hear it in the bridge speaker, then you will be able to hear it in the regular signal - because you can hear it. The difference won't be as easy to spot in the normal set-up, but it has to be there. Is it masked by other sounds? Maybe. But many audiophiles claim they can hear past the mask. This test will at least tell us if there really is something to hear, or not. That's the point, gentlemen. Take another look at the ladies in their underwear.
| quote: | | It doesn't need to be ABX. Somebody suggest a "better" protocol, if that one is a pariah. Why is that unreasonable? |
Ummm.... I HAVE.
Why is that unreasonable?
But you guys seem much more interested in psychology and parapsychology than in audio tests. That's OK, if that's what floats you boat., no wories :) |
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| KBK |
| quote: | Originally posted by macgyver10
You do realize that if this was being said on the street from your cardboard box and amongst your collection of empty bottles, you'd be elligible for enrollment at the local mental institution?
I understand, now, your choice of hero. The internet is a wonderful place. |
"I don't care if it rains or Freezes,
'long as I got my Tesla Jesus?"
See my siggie fer edification. Specifically the last quote. ;)
The common herd is just that: The Common herd. Nothing more. |
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| macgyver10 |
| quote: | Originally posted by panomaniac
But you guys seem much more interested in psychology and parapsychology than in audio tests. That's OK, if that's what floats you boat., no wories :) |
Um...sorry, but isn't the title of this thread "the JREF cable challenge test"?
I'm not putting down your test, I agree with you that it will lay bare the differences.
But the JREF, and myself (in the context of this thread), aren't interested in ACTUAL differences that can be measured. That's science. Both the JREF and I agree that your test will test for that.
That's why I said that we could use your test to help set up a JREF paranormal challenge test. If we could use a measurement system like yours to perfectly match two different cables (perhaps one cable in the "correct" direction and one installed "backwards") then we could test the claims that people can hear what can't be measured.
I'm only interested in proving THAT claim. I don't take issue with claims that have copious amounts of evidence to support them. |
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| macgyver10 |
| quote: | Originally posted by KBK
See my siggie fer edification. Specifically the last quote. ;)
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So what fish are you swimming with? That remains unclear.
Judging by the popularity of shows like Coast to Coast AM, I'd say there's a very large herd for self proclaimed "outside thinkers".
Actually your position is an easy one to assume, and defend. It's not, perhaps, as unique as you think.
Entertaining is perhaps it's most redeeming feature ;) |
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| SY |
| quote: | | Would love to read the critique of the test. Got links? |
You might poke around Stereophile's site to see if they've put up the old articles. At the time this was written, a PDP11 was exotic.
Basically, once the null gets to better than -60dB, just breathing near the circuit changes it and degrades the null. You get different optimum points for nulls at different frequencies- which is the right one? The amplified difference signal didn't sound very distorted except in extreme cases. And so on and so on. |
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| panomaniac |
| quote: | Originally posted by macgyver10
Um...sorry, but isn't the title of this thread "the JREF cable challenge test"? |
It is, it is. But I suppose I wasn't clear enough when I said:| quote: | | The title of this thread is “The JREF cable challenge test.” But I will be calling my test the “Balanced Bridge Test” to be clearer about how it functions. |
Sorry to be misleading. The JREF thing is a only a starting point. I did ask readers to forget about the paranormal thing. I'm more interested in the cable test then in the JREF. Should have given the thread another name. Too late now.
| quote: | | If we could use a measurement system like yours to perfectly match two different cables (perhaps one cable in the "correct" direction and one installed "backwards") then we could test the claims that people can hear what can't be measured. |
Yep! That's what I hope to do. Paranormal or not. The directional cable is a good one. How on earth could that work? Don't answer, please!!
But my test could easily show if it makes a difference or not. Or any other "strange" claim. Yes, even voodoo. As long as the claim is that the difference lies in the cable. Differences outside the cable, like voodoo that works on the mind of the listener, or the air in the room, well, I can't test for that. :xeye:
| quote: | Originally posted by SY
You might poke around Stereophile's site to see if they've put up the old articles. |
Will do.
| quote: | | Basically, once the null gets to better than -60dB, just breathing near the circuit changes it and degrades the null. You get different optimum points for nulls at different frequencies - which is the right one? |
Fair criticism. There are a number of obvious technical difficulties in this test, I'm surprised no one has yet mentioned them. But I hold out hope. =) |
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| Panicos K |
| As the least educated person in this discussion in physics,I think I have the right to make this question:If it was possible(I don't know if it is)to adopt the famous ABX test with all necessary ''adjustments''and''tuning''using the magic box,for a speaker test ,does the engineer side believe also that they couldn't tell the difference between a WAMM and say a LS3/5a?Please don't take this as a bad joke,I really want your opinion. |
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| Panicos K |
| And to clear my position,as I feel that it has been violated in a previous post,I bet that Panomaniac's test proposal would definitely show the difference clearly. |
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| macgyver10 |
| quote: | Originally posted by Panicos K
As the least educated person in this discussion in physics,I think I have the right to make this question:If it was possible(I don't know if it is)to adopt the famous ABX test with all necessary ''adjustments''and''tuning''using the magic box,for a speaker test ,does the engineer side believe also that they couldn't tell the difference between a WAMM and say a LS3/5a?Please don't take this as a bad joke,I really want your opinion. |
How did you manage to come up with the idea that the "engineer side" would not be able to hear a difference between two obviously different loudspeakers?
Not only would the difference be heard as obvious, but the difference could easly be measured acoustically and be equally obvious.
That wouldn't be the case with something like reversing a so-called "directional" speaker cable. |
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| Panicos K |
| I'm just wondering.In your post 779(do sp. cables make any...)you said to soongs I think ''...I would make sure all measurable differences were matched..''.So,if we could do the same with these speakers could you teell any difference?To my mind ''matched''actually mens .---- up both cables in order to ''sound''identical,that's why I wonder what would happen if you tried the same with dpeakers.Perhaps here some ''smart'' eq would help. |
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| SY |
| quote: | | To my mind ''matched''actually mens .---- up both cables in order to ''sound''identical, |
Why? |
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| Panicos K |
| SY,macgyver10 wrote''Personally,if I were to make a test like this,I would make sure all ''measurable''differences were matched'(I add here ''matched''=masked so to make it impossible to measure),since the claim is most often that it's heard,but impossible to measure''. What i'm asking is,if we match(mask) all measurable differences between WAMM and LS3/5a which includes sound level,balance,etc...would you be able to hear any difference?If yes,at which areas? |
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| macgyver10 |
| quote: | Originally posted by Panicos K
I'm just wondering.In your post 779(do sp. cables make any...)you said to soongs I think ''...I would make sure all measurable differences were matched..''.So,if we could do the same with these speakers could you teell any difference?To my mind ''matched''actually mens .---- up both cables in order to ''sound''identical,that's why I wonder what would happen if you tried the same with dpeakers.Perhaps here some ''smart'' eq would help. |
But then you're not comparing these two speakers anymore, you're comparing two speakers that in all measurable parameters are identical.
This would be impossible to accomplish due to the electro-mechanical and acoustical nature of a loudspeaker. All measurable quantities would be a long list including matching the radiation patterns of the drivers, the phase relationships between drivers and their acoustical centers, size and shape of the baffle and enclosure, impedance curves, on and off axis frequency responses etc. etc. etc.
Again, it has nothing in common with testing a speaker cable. |
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| Panicos K |
| macgyver10,of cource they are not the same cables,speakers,amplifiers,or whatever anymore.don't try to give any explanation why it is not possible to achieve such a thing.For me it's enough that even on a theoritical level you agree you wouldn't be able to tell any difference,although I wouldn't be surprised if by studying such possibility maybe there might be a way to do such a test.More complex perhaps but you never know. |
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| SY |
| Differences between speakers are heard routinely in blind tests (see, for example, the extensive work at NRC and Harman by Floyd Toole and several papers by Lipshitz), so don't drag us off topic. Stick to arguing cable tests. |
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| rdf |
| quote: | Originally posted by KBK
See my siggie fer edification. .... |
The foundations of an an excelllent aphorism are there, Malcolm needed more fishing to bring it to fruition. |
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| Panicos K |
| I'm sorry.I didn't mean to drag anyone off topic.It was the method of testing the cables I actually refered to.However,I'll be careful not to cause any problem to any disussion. |
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| macgyver10 |
| quote: | Originally posted by Panicos K
macgyver10,of cource they are not the same cables,speakers,amplifiers,or whatever anymore.don't try to give any explanation why it is not possible to achieve such a thing.For me it's enough that even on a theoritical level you agree you wouldn't be able to tell any difference,although I wouldn't be surprised if by studying such possibility maybe there might be a way to do such a test.More complex perhaps but you never know. |
However, I DO know, and I can assure you that you could NOT match the two speakers that you mentioned in every measurable parameter.
You could, however, match two pieces of speaker wire relatively easily. Particularly if that wire is the same piece just turned around end for end.
Also, "match" and "mask" have no similarity in the context of my posts. By matching two pieces of wire, I'm not suggesting that you change the electrical characteristics of the wire. I'm suggesting that you measure the signal at the speaker terminals, and check that frequency response, and amplitude are the same for both wires under test at listening levels.
I'm also suggesting that the amp and speakers be "high end" but not "esoteric" in as much as they won't be worried about varying LCR values as they pertain to wire (ie Cat5 high capacitance won't cause oscillation)
I'm suggesting making practical tests, not theoretical thought experiments for the purpose of argument. Those have their purpose, but are probably better for a theoretical physics forum, or philosophy forum. |
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| Panicos K |
| macgyver10,scientific research starts on a theory,so I believe that nothing is impossible.I am also sure you understood what I meant,and I accept that yoy deffended your position well.It is the test method I meant. |
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| Panicos K |
panomaniac'when I was in the hi-fi business,one of the things I was careful when the speaker cable pair was made of two single runs,was that the + was pointing at the oposite direction than the - .So,if you hear or measure differences this arrangement of the two conductors will serve you better.In fact,only this way the cable will work correctly,no matter what overall direction you might prefer.
- |
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| macgyver10 |
| quote: | Originally posted by Panicos K
macgyver10,scientific research starts on a theory,so I believe that nothing is impossible.I am also sure you understood what I meant,and I accept that yoy deffended your position well.It is the test method I meant. |
Well, while you enjoy a hollow earth full of dinosaurs, a moon made of cheese and thousands of other things that are impossible, I'll continue to know that the two speakers you've mentioned will never "match" in all measurable parameters.
It's not a situation where a "theory" has been presented, and science can prove or disprove it. You might as well be attempting to make you and your dog "match" in every measurable parameter. |
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| Panicos K |
| macgyver10,I'm 46 and I assure you that many times in my life,I would prefer to match myself and my dog in many more parameters than you might think. |
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| panomaniac |
Mr. Macgyver has mentioned some very good points back in post #59.
In this test, or most any other, the choice of amps and speakers is important. Macgyver also wants cables with the same FR; I don't really care, as that should be part of what we are looking for.
If you have two cables that measure the same in L, C & R, they should sound the same. There is even the school of thought that small differences in L, C, & R will not make a difference in the audio spectrum, because the speaker impedance is so low that it nulls out the differences below ~20kHz.
But what if we have two cables that "should" sound alike, according to electrical theory? We put them to the test. Is there really a difference? Is it enough to hear, not just measure?
The test would be easy with the directional cables. Just connect one the "right" way, the other the "wrong" way. Any difference? Would be easy to tell.
Then we get back to what amp to use, and what speakers. Macgyver is right that it shouldn't be something too exotic or unstable. Just something of high quality and relatively standard technology. Are any fancy cable enthusiasts claiming that their cable only sounds better on a certain amp or a certain speaker? No. Some DIY folks feel that way, but not the cable sellers, or they couldn't sell many cables.
To begin the test we might like to try Monster Cable vs. Zip cord of the same gauge. Then perhaps Cat 5 vs. same gauge Zip. Does the different L&C of the Cat 5 really make a difference? Then silver vs. copper - Teflon vs. PVC, etc.
There are a lot of cables to test, so it could go on forever, but a choice of well known cables would be a start. Then we could move on to measure those same cables against no cable. That's right, NO cable. How?
You can't really have no cable, and get any sound, but you could get close. One side of the bridge could a very, very short cable, for example 3cm of 14 ga. solid copper (or silver) with no insulation, touching nothing but the amp and speaker. That could be established as a baseline. All other cables will deviate from that baseline, the difference can be found with the bridge.
We would hope that out speaker cable isn't changing the signal much, so the cable that changes it the least would be worth looking into. Does any cable change the signal enough over the baseline to be heard? If so, is it any more than the other cables?
That’s the sort of thing we want to know. |
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| macgyver10 |
| quote: | Originally posted by Panicos K
macgyver10,I'm 46 and I assure you that many times in my life,I would prefer to match myself and my dog in many more parameters than you might think. |
Me too, a dog's life looks like something I'd enjoy, but it's impossible...
Speaking of Dogs, if they were the ones to have designed our stereo gear, rest assured that the "interesting stuff" would be far higher in frequency than humans can hear, and require considerably different design parameters. |
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| panomaniac |
| quote: | Originally posted by panomaniac
Mr. Macgyver has mentioned some very good points back in post #59. |
Ooops! I meant post #49!
This thread has gone to the dogs, anyhow. |
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| macgyver10 |
Panomaniac,
One of the most under-rated audio engineering geniuses is IMHO Bob Carver. Read the "controversy" portion of this article, where he used "difference testing" to succesful show up the Stereophool crew:
http://en.wikipedia.org/wiki/Bob_Carver
panicos might find this interesting too, because it shows the successful implementation of "matching" amplifier parameters through measurement, and then passing a test with a room full of "golden ears".
I'm only posting this as a illustration of Panomaniac's test technique used in a practical application, I'm not opening a debate on whether or not anyone likes or dislikes Bob Carver and his products. |
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| panomaniac |
Thanks MacG.
Hadn't seen that article before. Bob Carver was a clever fellow. He used to claim that he could imitate the sound of any amp just by changing the damping factor of his amps. Some people were convinced, others were not.
Guess that is what the controversy was about. Didn't know he used a bridge test. |
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| macgyver10 |
| quote: | Originally posted by panomaniac
Thanks MacG.
Hadn't seen that article before. Bob Carver was a clever fellow. He used to claim that he could imitate the sound of any amp just by changing the damping factor of his amps. Some people were convinced, others were not.
Guess that is what the controversy was about. Didn't know he used a bridge test. |
I think what was particularly innovative of some of his amps, however, is that he offered you the choice of the high Z output (low DF) and the low Z output simultaneously so that you could Bi-Wire your speakers and get the "best of both worlds". Votage source for the woofer, and current source for the mids and tweets.
Another thing that you have to give him credit for, is that he "listened" to his amps and designed them accordingly. Once the math and engineering was done, he had favourite source material that he would use to evaluate and fine tune the product. |
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