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June 20, 2009 - 3:00pm
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Comb filtering effects and sonics. Why would they 'exaggerate' findings?
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I think you have it forwards, uh I mean right.
Claiming that comb filtering is responsible is an easy cop out. It's something that can be measured and graphed. It's exactly what objectivists love, numbers they can spout to one and all that have almost nothing to do with reality. OK, they may have a very small significance.
To claim that a perceived difference in what you're hearing is caused by an inability to put your own butt in the same place in the same chair just boggles the mind. If that's so, moving your body while sitting in that very same chair should bring comb filter effects into play.
Come on you dial watchers, give it a rest. Let those of us who hear differences hear them in peace. Stop trying to be the audio police. You think we are delusional. We think you are damn near deaf.
You are wasting your time trying to convert us to your way of thinking. That's because we don't care what you think. Just go away, back to HA or wherever meter readers congregate.
"How can we expect to garner varying sonic impressions about gear when we are having to listen through 15, 30, or greater dB differences in frequency response as we even slightly turn our heads?"
Huh?
www.machinadynamica.com/machina68.htm
It's ONE of many issues. Only one. It is one of the primary acoustic issues. ONE.
How does it do various things? That is signal, situation, and listener dependent.
I'm trying to recall a post by you sans self-marketing.
I guess that's a constant, like comb filtering.
"I'm trying to recall a post by you sans self-marketing."
It's simply more convenient sometimes to launch images from my web site. Nothing, uh, darker, intended.
Not at all. As j_j said, comb filtering is only one contributor. Personally, I feel the reason people think they hear changes that do not exist are in this approximate order:
1. The short-term nature of human hearing. Hearing is frail, but many people do not realize this. If I play a 10-second song fragment for you, then play it again right away 1 dB louder, you'll easily notice the volume increase. But if ten minutes passes between plays, you're much less likely to notice.
2. Delusion. Not the psychotic type we sometimes see in posts with delusions of grandeur addressing a large "public" audience. What I mean is more along the lines of expectation bias and placebo effect.
3. Learning the music. Often people claim that after changing speaker wires, or demagging their LPs or whatever, they were then able to hear some subtle instrument that had previously been "veiled." But the instrument was always there, and audible, they just didn't notice it until after a few hearings. We've all "heard into" music more on subsequent playings, and that just happens anyway with repeated exposure to the same piece of music.
4. Comb filtering.
Yes! But what really happens is the comb filtering adds a randomization. Then 1 through 3 above can dominate.
Buddha, if you have a better explanation that does not rely on nonsense like "I can hear things that audio engineers don't know how to measure" I'll be glad to hear it.
--Ethan
Ethan-
This is a completely valid point, especially if the demo material is unfamiliar. That's why when doing demos I always use the A-B-A format where A=the before and B=the after. Doing a couple of back and forth trials just makes good sense, with extremely different music of course.
"2. Delusion. Not the psychotic type we sometimes see in posts with delusions of grandeur addressing a large "public" audience. What I mean is more along the lines of expectation bias and placebo effect.
3. Learning the music. Often people claim that after changing speaker wires, or demagging their LPs or whatever, they were then able to hear some subtle instrument that had previously been "veiled." But the instrument was always there, and audible, they just didn't notice it until after a few hearings."
Ah, some more pet theories. Fascinating.
Ethan, if that's so, then I would expect objectivists to have noticed differences, too.
You yourself have claimed to have "never been fooled, not once."
If it adds randomization, then I'd expect you to have been fooled here and there based on random differences in the different listening environments you've been exposed to.
If you've never been fooled by this randomization, then wouldn't that be a tacit admission that either this randomization doesn't actually occur, or that you tend toward always hearing the same thing?
Randomization should be making it so everybody is hearing these differences, but objectivists never do!
So, subjectivists can hear this 'randomization,' but not objectivists.
Can you explain, without some magic hocus pocus why, on the one hand, you don't hear differences based on this randomization, and the people, on the other hand, who do hear diferences but then you call them random?
At risk of enraging the marketeers...
1) I think we also have wandering attention. When playing a cut, even while trying to listen 'attentively,' our focus wanders between sounds; the bass at one instant, maybe a horn part the next, on to the vocals, etc...
When we do this and then play the same song after 'doing something to listen for,' our attention does not follow the exact same pattern/sequence that it did just a few moments before, sometimes leading one to think, "Hmmm, that bass caught my attention this time," or some similar thing, and we wonder if there is a difference in the sound when, in fact, it is just that we are focusing our attention a little differently.
2) (Purely for discussion sake, not claiming this is fact) In the context of comb filtering, I wonder if we 'imprint' what we first hear when we start a cut, listening session, etc, and that's what our brain uses to 'calibrate' the way we hear the system. Then, when we walk around or shift in our seat, our comb-filtering-filter works to keep that sound in keeping with how the sound started.
That might be why someone may hear a bass emphasis (due to comb filtering) that remains a consistent impression through a listening session and changes in location while still seeming to hear 'the same sound' rather than a constantly changing m
You are missing something very important. I know how frail our hearing is, so I'm the first to say I have no idea if the sound really changed. Unlike true believers, I don't pretend (or unintentionally fool myself) that I can discern A versus B when the differences are very small. Of course, I can tell 3 dB of treble boost in one version versus another. But subtle details are much more difficult to discern unless the comparison is short samples played one right after the other. Since most tweaks (demag vinyl, swap speaker wires) are totally in the mind, it only makes sense that any "differences" are very small. Therefore it's probably wiser to start from the perspective that nothing really changed, and then question why some people think they heard a change.
IMO this is the entire issue in a nutshell.
Yes.
Nah, hearing is too short term for that unless the difference is large.
Okay, you're starting to win me over to that viewpoint.
No shit. How many times have I listed expectation bias as a main contributor?
--Ethan
Maybe it's time to discuss the present theory of human cognition as it relates to the periphery and some cognative effects.
There are, it is conjectured, three steps. The first, which I will call, despite the psychologists lingo, partial loudness memory, can be estimated at a megabyte per second or so of information, and persists about 200 milliseconds maximum. This is very nearly "unguidable" by the intellect, and consists of something close to the input on the auditory nerve with some small integration. The "partial loudness" term is a more formal term, it means the loudness of what hits the ear sorted by the cochlear filters into many overlapping channels.
From there, the information is sorted into features. This can be guided substantially by concious or unconcious processes, loses a great deal of information, and results in thereabouts of a kilobyte/second of information. This level of information persists seconds, arguably to minutes.
Those are further abstracted, and turned into 1 or 2 bytes/second of information that can be rendered into long-term memory.
There's a very important point here. Even if we have exactly the SAME sound twice, and, for instance, you aren't listening for it the first time, and you are the second time, you will have and remember greatly different experiences BECAUSE of the cognative effects.
How does this relate to listening? It means, and rather convincingly, despite any flaws (there have to be some!) in the modern theory, that all that is necessary to remember different things is to direct attention to different parts, have attention redirected by internal or external stimulii that, etc.
This combines with expectation to create all sorts of remembered, experienced effects that HAVE NOTHING TO DO WITH THE ORIGINAL AUDITORY STIMULII.
And therein lies, I think, the gulf between those accused of "objectivism" and those accused of "subjectivism". While, as I said, there are undoubtedly holes and mistakes in the theory, as I recite it, or as it would be described in a large paper on cognative processing of auditory stimulii, there is no doubt that something of the sort goes on, and creates different recalled observations from the same stimulii.
That's all it takes to have different experiences, OR get different results on a test with a nocebo.
>>> "comb filtering is only one contributor. Personally, I feel the reason people think they hear changes that do not exist are in this approximate order:
1. The short-term nature of human hearing. Hearing is frail, but many people do not realize this. If I play a 10-second song fragment for you, then play it again right away 1 dB louder, you'll easily notice the volume increase. But if ten minutes passes between plays, you're much less likely to notice.
2. Delusion. Not the psychotic type we sometimes see in posts with delusions of grandeur addressing a large "public" audience. What I mean is more along the lines of expectation bias and placebo effect.
3. Learning the music. Often people claim that after changing speaker wires, or demagging their LPs or whatever, they were then able to hear some subtle instrument that had previously been "veiled." But the instrument was always there, and audible, they just didn't notice it until after a few hearings. We've all "heard into" music more on subsequent playings, and that just happens anyway with repeated exposure to the same piece of music.
4. Comb filtering." <<<
***********
You, Ethan, list four reasons for how changes in the sound can be perceived.
Of the four you list, which one, in your opinion, would explain such as John Atkinson's comments at the Montreal show ?
>>> "I was working in a room outside Michael's listening room, but still listening to the music being played. It sounded good and then there was a short gap and then I heard the same track again but this time with more bass. I asked Michael "What were you doing just then ? There is more bass now ?" To which Michael replied. "I have just applied a demagnetiser to the LP."
Of the four you list, which one, in your opinion, would explain how Ed Meitner (and now many others) could describe how cryogenically freezing CDs, components, cables etc can give improvements in the sound ?
Of the four you list, which one, in your opinion, would explain how the Sony engineers (amongst others) could describe how applying a particular colour to a CD can give improvements in the sound ?
Regards,
May Belt.
Excellent post j_j. May and Geoff (and many others) should try harder to understand this.
--Ethan
As a rule I ignore your posts because nothing I say ever seems to sink in. But I'll try one more time:
I wasn't there so I can only guess, but probably comb filtering as John moved around.
Again I wasn't there, and I assume you weren't either, so I can only assume any and all four can apply.
--Ethan
"I wasn't there so I can only guess, but probably comb filtering as John moved around."
Nope, that couldn't be it. He had already been moving around for some time. He didn't observe the dramatic change in the sound until right after the demag was utilized.
Any more pet theories?
I have some very simple questions for you.
1. Have you ever tried the Furatech D-Mag?
2. If not, why not?
3. How can you dis a device you have no first hand knowledge of?
Please don't try to weasel out of answering the last question. You are in a position to beg borrow or otherwise obtain one for yourself for testing. If you are to cheap to put up the money we could start a stop Winer from whining fund.
The issue is not whether you believe the device works or not. It's have you tested it yourself. If you won't personally test this device please shut up and go away. You have virtually no credibility on this forum now so merely testing the Furatech would give you some.
BTW: Your latest claim about comb filter effects has put your credibility at somewhere around minus 20.
Frankly the devices you manufacture and sell no matter how good they are are things that I and I suspect a lot of other posters here would never buy simply because of your "know it all" attitude.
If you simply test the Furatech device in the company of others and honestly report the results you would incur a lot less animosity. The test must be in the presence of others because I don't trust you to report anything honestly if you don't like the results. How about JJ as a witness? I might not like what he says most of the time but I believe if he heard a difference he would not lie or obfuscate. I think he would try to find out why he heard a difference.
What do you say "Mr. Winer"?
To everyone:
Please excuse my thread stealing. Someone needed to ask our resident "Whiner" what I just did.
What do you mean "no" first hand knowledge? They claim it is a demagnetizer. You'd be surprised how much you can find out about magnetization and demagnetization without owning a Furutech. You don't have to cut yourself to know you bleed.
Don't include me. I'll take better sound regardless of my personal feelings about the makers' attitude.
Scott, you could save alot of money by simply using full size bedroom pillows, or for a little work, rolls of R19 insulation in the corners and if necessary midway along each wall. And they are easily removable. Works very well.
Try 2 by 4' acoustic ceiling tiles at first reflection points along side walls and in ceiling if possible. Inexpensive and works very well for almost any room. Oh, and did I state very inexpensive.
Hope this helps.
Thanks for the tips SAS. I've made DIY corner and bass traps. I've also used R-19 in wood frames with grill cloth covers in the first reflection points and I've got diffusers behind my ESL's.
I have learned a little in the 41 years I've been involved in this "hobby".
Your welcome. Inexpensive yet highly effective, and mobile.
Please don't try to weasel out of answering the last question. You are in a position to beg borrow or otherwise obtain one for yourself for testing. If you are to cheap to put up the money we could start a stop Winer from whining fund.
It's an idea, but before it would ever happen, we'd all go broke.
BTW: Your latest claim about comb filter effects has put your credibility at somewhere around minus 20.
I think he hit -20 when he said that none of us uppity "audiophools" would hear any differences from his demag test,
and then that we were all "chickenshits" for not wanting to take it, but all the while claiming that he would conduct the test fairly and honestly. Man, was that ever a ROTFL moment.
Recap:
Q. Okay, what did we learn in Winer's classroom today, kids?
A. "If somebuddy claims to hear sum thing you don't believe they should be hearing, or if they don't hear something you do believe they should be hearing, then say that it's because of "comb filtering"!"
Frankly the devices you manufacture and sell no matter how good they are are things that I and I suspect a lot of other posters here would never buy simply because of your "know it all" attitude.
I know I'm not ever going to buy any of his products because of his attitude. I don't even believe the graphs on his site he keeps referring to that he uses to help sell his products are accurate. They could have been fabricated for all I know. Attacking his competitors is another turn off for potential customers, I think.
If you simply test the Furatech device in the company of others and honestly report the results you would incur a lot less animosity. The test must be in the presence of others because I don't trust you to report anything honestly if you don't like the results. How about JJ as a witness? I might not like what he says most of the time but I believe if he heard a difference he would not lie or obfuscate. I think he would try to find out why he heard a difference.
I have no reason to believe that myself. Both of them are known to be extremely biased against unconventional ideas and applications, and that is more than likely to prejudice their listening test, whether sighted or ABX. It's not for nothing that every non-audiophile (objectivist) who claimed to have heard a recording of the demag, including Ethan, claimed they heard no difference (although it took Arny a few days after his tests to realize he heard no difference!). And every audiophile (aka subjectivist) who heard the recordings, heard a difference.
What do you mean "no" first hand knowledge? They claim it is a demagnetizer. You'd be surprised how much you can find out about magnetization and demagnetization without owning a Furutech. You don't have to cut yourself to know you bleed.
Yes but just because someone is bleeding, doesn't mean you know how they were cut. Your argument is specious. You can't just employ any demagnetizer and then say the effect is going to be the same as the Furutech product. Especially when you don't know anything about the Furutech product. To say every device that utilizes demagnetization is the same as saying every magnet is the same. This is how people allow prejudices to color their perceptions.
Quote:
Frankly the devices you manufacture and sell no matter how good they are are things that I and I suspect a lot of other posters here would never buy simply because of your "know it all" attitude.
Don't include me. I'll take better sound regardless of my personal feelings about the makers' attitude.
There's more than just "sound" to consider when doing business with an audio dealer. Integrity and reputation come into play as well. I would not do business with Ethan because of the fact of how many times I have seen him conduct himself in a dishonest manner on this forum. I figure that if you are dishonest on an audio forum, you're going to be dishonest in your business life as well. Especially since this isn't just a social gig for him, so the lines are blurred. If a dealer is dishonest but has a great product, where will you be if you have an issue with it, or the transaction, if the dealer refuses to be honest and take responsibility for their products or actions? For as much as I tout the importance of better sound, there are sometimes things as equally important to consider.
You are preaching to the chior on that one. I'm all about DIY when it comes to room treatments. I was just sayin I wouldn't pass on a purchase of anything just because I didn't like someone.
Let's not get to caught up in analogies. They don't prove anything, they just help illustrate points. My point being
that one does not have to try something to know soemthing about the *claim.*
How do you know that? I have heard testimony quite to the opposite. There are people out there using generic demagnetizers and reporting similar results.
We certainly know what the makers are claiming. So we actually do know something about it.
It isn't quite the same thing. But there are some basic universal truths about demagnitization. That being it demagnetizes things that are magnetically charged. In so far as that goes they are all *basically* the same. Some may be more thourough than others and they certainly come in different shapes and sizes but if it is a demagnetizer it....demagnetizes things.
I'm not talking about perceptions here. I'm talking about demagnitization. and the fact that "we" do know quite about about it without having a Furutech in hand. So the charge that we know nothing is plainly false.
Can't go there with you. There is no evidence that Ethan is a dishonest or irreputable business man. You are pleading that we use prejudice to judge a man's business ethics. No way. Not me. Aint gonna happen.
Thanks for the clarity Scott. Take care.
Steve
I can dismiss that a vinyl record is improved by demagnetization without trying it as easily as I can dismiss other crackpot theories without trying them. For example, I don't have to try out a tin-foil hat to know that it will not prevent the government from reading my mind.
Based on the tone of your post, I'm sure you'll forgive me for ignoring you in the future.
--Ethan
Aside from the issue of whether tin foil hats work, I think what worries me most is that you believe the government is reading your mind. Then again, that might go a long way to explain some of your unscientific comments recently on demagnetization, acoustic products and speaker wire. I suppose "magnetism" must also be a "crackpot theory" for you, because you don't fully understand how it works.
Well sure you can dismiss it out of hand. Such is the nature of a free society. But anyone can dismiss anything you say out of hand with equal effectiveness. Now if you actually show why then your dismissal will carry more weight.
For example's sake, how about one instance where you find the use of 'magentism' to be of the 'crackpot' variety?
Bracelets?
Hats?
Wine spouts?
Under your mattress?
I'd just like to get a handle on where 'magnetic crackpotism' would happen for you.
Ethan gaives an example of where he thinks claims of magnetism leave the bounds of possibility. How about you?
What if Ethan claimed that tin foil hats improve the sound of Hi Fi systems?
If the science on this is correct, it does not rule out, and does not explain why I hear the reproduced sound of instruments that appear to interfere with each other, preventing me from isolating the instruments as individual ones as well (with my system in the "before" state), and then (with my system in the "after" state) I could hear this effect much better (judged as an improvement). I know this from long exprience with my system. I try to hear into the music for more enjoyment, and found it clearly better in the "after" state. The difference is surprising enough that I started to play more LPs one-at-a-time to hear this effect, and each LP sounded like it was different than before in that same way.
This improvement is clear to me, and continues to this day, heard in various parts of the room, but best enjoyed when seated equidistant from the two speakers. I cannot attribute this to simple comb filtering. What I hear and describe is what I would think a musician might hear and describe in that way. I have not given it enough thought to come to any scientific explanation, because I know that there must be one.
This one apparently goes against the 'frail auditory memory', which I'm sure has been demonstrable under certain given tests. What I have done demonstrates *to me*, that something else is also possible, and perhaps that auditory memory is not as frail in some cases as may be generally accepted. Have you any thoughts on cases where auditory memory exhibits robustness, versus when it exhibits frailness?
For example's sake, how about one instance where you find the use of 'magentism' to be of the 'crackpot' variety?
Well Buddha, I wasn't claiming I did or even could. Only that Ethan doesn't fully understand how magnetism works. I know that because if he did, he would inform scientists who have been grappling with such questions as; the cause of EM forces (what creates the energy), why the strength of an EM field is what it is, why it decreases with the square of the distance from the charge, why the fields of multiple charges add the way they do, why the field of a point charge is radial, etc. etc.
Bracelets?
Perhaps. Or not.
Hats?
Perhaps. Or not.
Wine spouts?
Perhaps. Or not.
Under your mattress?
Perhaps. Or not.
I'd just like to get a handle on where 'magnetic crackpotism' would happen for you.
Saying everything about magnetism is understood, I guess.
Ethan gaives an example of where he thinks claims of magnetism leave the bounds of possibility. How about you?
I would never make such an ignorant and self-defeating statement as Ethan. For there are no "bounds of possibility". There is only known, and unknown. And that changes all the time.
What if Ethan claimed that tin foil hats improve the sound of Hi Fi systems?
Then I would tell him to stop blindly believing everything that j_j tells him.