Steve Eddy said:
The point Ophth's making is that that isn't the only question. That's the skeptic's question. The believer wants to know, what's the chance of the test failing to find an audible difference if it's really there? If the difference is very small (but real), you'll need a huge sample size to find it with any confidence. On the other hand, if the difference is big then it'll be easy to find.
If the difference is moderately strong (say, given an infinite number of cables, one could correctly classify them 60% of the time), then the chance of finding a statistically significant effect in an experiment with a sample size of 100 is >0.6225. If the difference is stronger than that (>68%), the probability of finding a difference if it exists is virtually 1.
BTW, there are some useful calculators for figuring this stuff out here:
http://calculators.stat.ucla.edu/powercalc/
Hi,
The difference is big enough to be noticed but after a while it doesn't seem to get in the way of music reproduction...
So, it seems the cable breaks in and the initial difference vanishes into thin air.
Just my experience...
Cheers,😉
The difference is big enough to be noticed but after a while it doesn't seem to get in the way of music reproduction...
So, it seems the cable breaks in and the initial difference vanishes into thin air.
Just my experience...
Cheers,😉
I would suggest a pilot study before the one you have proposed.
Send everyone two cable pairs. One normal pair, one with normal left channel and crappy right channel. Maybe use cheap telephone cord, or something.
Under blind conditions, ask if the imaging is altered.
Compare:
Percent of times the good cords have altered imaging.
Percent of times the crap cords have altered imaging.
Compare those. Then we can look at the difference in image altering between the cables and estimate an amount of difference we expect between your directional cables.
Send everyone two cable pairs. One normal pair, one with normal left channel and crappy right channel. Maybe use cheap telephone cord, or something.
Under blind conditions, ask if the imaging is altered.
Compare:
Percent of times the good cords have altered imaging.
Percent of times the crap cords have altered imaging.
Compare those. Then we can look at the difference in image altering between the cables and estimate an amount of difference we expect between your directional cables.
Multiple test listeners just determines the average hearing accuity of the set of listeners.
Frank and I understand the sound of cable direction and ought to get our tests 100% correct.
If we do get 100% correct, trialling with other listeners who do not get 100% correct will just prove that these other listeners are not clearly hearing the effect.
Eric.
Frank and I understand the sound of cable direction and ought to get our tests 100% correct.
If we do get 100% correct, trialling with other listeners who do not get 100% correct will just prove that these other listeners are not clearly hearing the effect.
Eric.
Hi,
We OUGHT to but that doesn't mean we actually WILL.
There's always that Vampire lurking around the corner....
Cheers,😉
We OUGHT to but that doesn't mean we actually WILL.
There's always that Vampire lurking around the corner....
Cheers,😉
I emailed Steve Eddy a bit and I believe my sample size is right.
Essentially you'll have pair A and pair B.
Usage of pair A will result in an image shift XA percent of the time.
Usage of pair B will result in an image shift XB percent of the time.
We are going to compare these percentages to try to prove a difference or to prove no difference.
(estimated difference of 0.1% gives 1.6 million samples needed.)
(estimated difference of 1% gives 16,243 samples needed.)
It is possible that you will prove a difference with a few hundred trials. But only if the difference is much larger than the 1% I estimated. MrFeedback certainly seems to think it is. (running separate trials on his numbers would be no problem.)
One other thing. When each person does many trials, they need to "blind" themselves on each trial. If MrFeedback does a trial on monday and is sure that A is good and B is bad. He needs to hide the A and B marks for his trial on tuesday, otherwise he is biased on tuesday.
Essentially you'll have pair A and pair B.
Usage of pair A will result in an image shift XA percent of the time.
Usage of pair B will result in an image shift XB percent of the time.
We are going to compare these percentages to try to prove a difference or to prove no difference.
(estimated difference of 0.1% gives 1.6 million samples needed.)
(estimated difference of 1% gives 16,243 samples needed.)
It is possible that you will prove a difference with a few hundred trials. But only if the difference is much larger than the 1% I estimated. MrFeedback certainly seems to think it is. (running separate trials on his numbers would be no problem.)
One other thing. When each person does many trials, they need to "blind" themselves on each trial. If MrFeedback does a trial on monday and is sure that A is good and B is bad. He needs to hide the A and B marks for his trial on tuesday, otherwise he is biased on tuesday.
If Frank and I get our results 100% correct over as many trials as you like, then cable direction is audible on our systems, no ifs and no buts.
I demonstrated interconnect directionality to a sound engineer colleage today and he heard it clear as day, just as I do.
Sure, this was not a blind experiment, and did not need to be.
He even jokingly asked if we were listening to two different cables.
Eric.
I demonstrated interconnect directionality to a sound engineer colleage today and he heard it clear as day, just as I do.
Sure, this was not a blind experiment, and did not need to be.
He even jokingly asked if we were listening to two different cables.
Eric.
I agree.mrfeedback said:
I think it would be interesting to do it blind. See if there is a person around who isn't interested in this issue and have him switch for you guys so you are both blind. Of course, don't let him indicate to you which way he has hooked it up.
Little story: I do mixing for our band at church. One time in practice the lead singer said that there is way too much recorded background music in his stage monitor. So I turned down the music in the stage monitor mix.
I said, "Is that better?"
He says, "Yeah. Thanks."
Then I realized that I had actually turned down the guitar in the tape out mix. I had actually not done anything to his mix!
Sometimes our minds play tricks on us. Have you ever had that happen?
As we used to say in Histology class, "you have to learn to imagine things."
A Blind Bat Can Hear It.........
However, he was able to clearly hear the difference such that after a couple of A/B experiments that he was able to indicate his clear sonic preference according to direction, and perfectly reliably so.
I really do not understand why so many of you have problems with this concept, and problems hearing it.
Eric.
The test was blind in so much as he was not visually sure whether I swapped directions or not.Ophth said:
However, he was able to clearly hear the difference such that after a couple of A/B experiments that he was able to indicate his clear sonic preference according to direction, and perfectly reliably so.
I really do not understand why so many of you have problems with this concept, and problems hearing it.
Eric.
Hmmm....In a truly blind test, the listener will know which cable are being used. If he knows they've switched, but can't see the cables, it's still not blind.
I'm not saying that there's no difference! I'm not discounting what you hear. I'm saying that the difference you hear is due to either an audible difference OR to your mind playing tricks on you.
Surely you've experienced the phenomenon of noticing a difference between cables - only to be told that the switcher never changed them?
I'm not saying that there's no difference! I'm not discounting what you hear. I'm saying that the difference you hear is due to either an audible difference OR to your mind playing tricks on you.
Surely you've experienced the phenomenon of noticing a difference between cables - only to be told that the switcher never changed them?
Re: A Blind Bat Can Hear It.........
'Cause it's not real ?
Just another possibility
😀
mrfeedback said:
'Cause it's not real ?
Just another possibility
😀
Hi,
I'm very willing to accept that my mind can play tricks on me once or even a few times.
What I can't accept is that my mind would play tricks with me 15 years in a row.
That and other concurring experiences and feedback (no pun intended) from others alone makes it at least a pseudo scientific experience to my mind.
Cheers,😉
I'm very willing to accept that my mind can play tricks on me once or even a few times.
What I can't accept is that my mind would play tricks with me 15 years in a row.
That and other concurring experiences and feedback (no pun intended) from others alone makes it at least a pseudo scientific experience to my mind.
Cheers,😉
I'd say that the fact you've held the opinion for so long makes you less likely to be objective about it now.
As you say, "...I can't accept..."
As you say, "...I can't accept..."
Hi,
Allow me to politely turn the table and say that you have difficulty to accept.
Mathematically it's the same thing except that I state to have the experience whereas you do not.
I accept alot of things but my belief is not just based on MY belief alone, neither is it based on my experience alone.
Too bad you guys have so much catching up to do and let's just keep it at that for the time being.
Cheers, 😉
Allow me to politely turn the table and say that you have difficulty to accept.
Mathematically it's the same thing except that I state to have the experience whereas you do not.
I accept alot of things but my belief is not just based on MY belief alone, neither is it based on my experience alone.
Too bad you guys have so much catching up to do and let's just keep it at that for the time being.
Cheers, 😉
Look 9 posts above this one where I say:
Look what I agree to. I mean that. If MrFeedback can ID the backwards cable 10/10 times or even 90/100 when he doesn't know what he's listening to then there's a difference. I'll agree to it. I'm not saying there's no difference. I'm saying MAYBE there's no difference. I don't know. Maybe you're right. I have no idea, though, so I can't be "right."
I think I am open minded about this.
I know some very smart people who have believed some incredible (in the literal sense) things for a lot more than 15 years. Term of belief is not a measure of accuracy.
Hey, for a lot more than 15 years, I've held onto the irrational belief that I can someday become a rich man.
SY said:
for centuries, people believe the earth is flat; for decades, people believed that we could travel faster than light; etc.
if smart people can believe in such horribly wrong things, what's so hard to believe that lesser folks cannot?
SY said:
millwood said:
I don't think it can be described as belief. Belief is something that we don't really know to be true, but we we choose to accept it as such.
If we are talking about cables, for someone who hears the difference, it's not a belief anymore, but an observed fact. Only those who never observed it, can still talk about belief, one way or the other. There are also some who changed their belief at one time, but this can only mean that they had never observed it as a fact in a first place.😉
PS: A note to Millwood. Out of curioisity, I had my hearing checked last Monday. I was told that it's "perfect" and much better than average. So I'm not half deaf, like who???😉
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