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Old 20th September 2005, 07:47 PM   #21
SY is offline SY  United States
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Cork. You guys are world's largest producer of cork. That's why I always check under my car for bombs when I'm visiting Portugal.
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Old 20th September 2005, 10:46 PM   #22
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Originally posted by SY
Cork. You guys are world's largest producer of cork. That's why I always check under my car for bombs when I'm visiting Portugal.
SY, this isn't funny.
Who are you comparing us to?

My post was not related to cork, but forget it...
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Old 21st September 2005, 12:21 AM   #23
PauSim is offline PauSim  Portugal
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Originally posted by carlosfm


SY, this isn't funny.
Who are you comparing us to?

To the elephant that would bother with a biting ant so that the ant could feel important? Not funny at all

HereŽs a much realistical joke:

An ant and an elephant were walking side-by-side through a desert . After a while the ant looks back and says:
"Wow! Look at all the dust weŽre raising!"




Quote:
Originally posted by SY
Cork. You guys are world's largest producer of cork. That's why I always check under my car for bombs when I'm visiting Portugal.
Sy, youŽre making a bad name of our hospitality. Here in Portugal we do not hyde bombs under cars. We welcome visitors with bottles of champaigne. WeŽll even point one at you just to show you another sample of our products.

(Cheers)
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Old 21st September 2005, 01:55 AM   #24
SY is offline SY  United States
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Paulo, the Amorims have not been quite as generous as you!
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Old 21st September 2005, 03:21 PM   #25
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Originally posted by SY
Paulo, the Amorims have not been quite as generous as you!
SY, I don't know what's the problem with Amorim, probably they only sell large quantities.
But hey, generalizing a hole county (or people) by the business experience with one company is not wise, is it??

Would it be logical to think that all americans are as smart as Bush?
Of course not...
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Old 21st September 2005, 11:48 PM   #26
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Well I have run out of ways to explain myself here. Honostly, much of what you say would not jive in the professional scientific community, though you think it does. Doint DBT's as you feel they should be done would have far more intervening variables than you are willing to accept, and you seem to still be making a presumption of our senses that does not fit the model accepted by the scientific community as a whole. Our sense's simply can not due what you seem to think they can, no amount of "reasonable" time would allow our sense of sound to absorb enough to tell a difference reliably, and the differences dont have to be that sudtle either. Yes I would expect that somebody could hear the differnece between an amp that makes 1% distortion and .001% distortion, but again, if such differences are all that matter, then we dont need DBT, a simple distortion measurement would do fine. However, if you believe, as I think most here do, that there is more to sound then what we can measure, hence the need for something like a DBT, then my point remains valid.

The standard for which you call, "My Standard," is simply how things are done in any human based scientific experiment. You must create a standard to keep things consistent and give you something to compare with. Though you may call this "My Standard", it really is not, it is how things are done, and the standard is validated, usually more than once, before its used reliably, making it simply a standard. Like I said, its not perfect, but agian, its for more valid than a DBT would be in this sort of scenerio. DBT's are simply a small part of measuring in an experiment, if all you did was that, and you were to submit the results of a simple DBT to publication panel, it would be laughed out of the room. I do not believe that DBT's really have any place in this sort of experiment, but if you did do one of sorts, it still would have to be only one small part of many experiments used to measure the differences found. You would have to train the listener, again, for consistency. You would have to standerdize terms, for more than they are now, and then run each listener through a series of standardized tests, inwhich the listener scored specific known variables, all to ensure that each listner used in this panel is able to score reliably and consistently. Not only with themselves, but with others.

As for the color cards, and picking a curten and living with it. My feeling is that, for some this is true, for others it is not. Some people are fussy and picky, and most research suggests this to be both a mix of psychological quirks and actual physical differences. Some people are more sensitive to color than others. Some are more sensitive to certain colors than others. A card shown back and forth in a DBT would still only give a very small sampling of what the person is going to have to live with. Once they get that big picture, say a room full of these curtains, and they live with them for months if not years, then certain people might begin to find the color just not quite right. Others may be happy. Thats all an issue of personal taste, but it still matters, as the same applies to most everything. In music and audio equipment, Some people can not hear as well as others, some are more sensitive to certain frequencies than others, etc etc. Then you have personal taste, which also effects perception of sound. Which by the way, my experimental design proposal here would eliminate the variable of personal taste, a DBT in and of itself does not. My point with all of this is that two amps which sound somewhat similar, in time may begin to seem quite different as you live with them, and some people may find the difference worth the huge cost, even if they are sudtle.
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Old 22nd September 2005, 01:12 AM   #27
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I will back up my response here with someone who has done a great deal of research, over 35 years worth, in something he calls perceptual organization, with regard to sound. His area of study is similar enough to what we are attempting to do here that his methods would transfer over easily, infact, his methods are basicly the same as mine, though he is more willing to call this completely subjective than I am, he too objectifies his subjective results through systems of coding and practice for consistency. The reason he does this, and the same reason I am saying that traditional, Yes/No or Right/Wrong measures using DBT's, is that they are not sensitive enough, and subjective experience can be far more sensitive to differences. He even states in one of his articles, "Auditory Scene Analysis and the Role of
Phenomenology in Experimental Psychology"(ALBERT S. BREGMAN), that visual studies have an edge in when being published, because they can show through visual drawings the subjective methods used, and everyone can see for themselves the differences, but not with Audio. You have to hear it to understand, and so people are suspicious.

My point for why the commonly proposed Double Blind Testing is bad is because, as its proposed, it does not measure the sound of an amplifier in an objective way. It only eliminates visual bias and experimenter bias, and that is not all that matters. You still have personal prefrence for sound, and way of describing the difference, unless all you want is, yes it sounds different, no it doesnt, or its Amp A, no its Amp B, which again, has its flaws. I could show you that DBT's used for color are flawed, that if I showed you two different, yet similar color cards back to back, and asked you to identify which was A and which was B consistently over many trials, you would get as many wrong as you would trying to identify the different amps, but that doesn't mean they aren't different, nor does it mean that you can't tell the differnce, it simply means that the test is not sensitive enough to allow you to tell the difference, so it lacks validity. Hence the need for a subjective measure. However, to make it valid (it already has very strong ecological validty because it is subjective, but weak internal validity because its not consistent), we create a way to make it consistent. As for DBT's not measuring what you think they are, keep this in mind, a really common problem is the understanding of what measuring sensory perception. Even in psychology that term has come to mean measuring a difference that exists when the senses are stimulated. Psychologist's do their best to attempt to measure this change accuratly, by eliminating the problem of actual human perception, which includes a lot of brain processing which introduces biases based on past experience, mood, heart rate, moon phase, etc. However, my point here, and Bregman's point is that, that is impossible. Now an actual scientist would argue that it is not, but again, he would not use a DBT to prove this, they simply do things like measure the biological response of the body to the stimulus, such as brain activity, or chemical's in the blood, which can change from the stimulus, such as the introduction of an Amino C or other indicator. The other way, the place where a DBT would play a role, but again, it would have to be modified from how you all propose its use, is to attempt to objectify a subjecftive experience. Each click of that switch to change between amp's is still only changing our experience of the amplifiers sound, not a direct measure of the amp itself. We attempt to eliminate bias by removing visual bias, interviewer bias, it controls for room, speakers, etc. Which is all needed, however, then what? How do you code the data recieved from this test, how do you extrapolate from the responses, especially if its turned into a sensitive test, anything meaningful. That is where my methods come in, which is to standardize the reviewer through training and education in how to hear the differences, how to verbalize the differences, etc.
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Old 22nd September 2005, 01:22 AM   #28
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Why would people try to identify different amps ? Arent they supposed to just say "this one sounds better to me" ? Then after 50 people say "this one sounds better to me" and only 12 people say "that one sounds better to me" you declare a winner .

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Old 22nd September 2005, 01:25 AM   #29
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unless all you want is, yes it sounds different, no it doesnt
That strikes me as a pretty damn good place to start.
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Old 22nd September 2005, 01:28 AM   #30
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SNIP

Quote:
Originally posted by pjpoes
Which is all needed, however, then what? How do you code the data recieved from this test, how do you extrapolate from the responses, especially if its turned into a sensitive test, anything meaningful. That is where my methods come in, which is to standardize the reviewer through training and education in how to hear the differences, how to verbalize the differences, etc.

I dont get it ? Put a set of speakers in a room. Cut wires. Hook up an A + B switch. Make sure that it all = itself out to a level that equipment would consider = then bring in the subjects .

Play a song and switch between amps. Even if you play 4 bars then go back play the same 4 bars again with a different amp. If there is a difference and the subject likes that difference have them write it down or better yet raise their hands when the sound they prefer is on. I dont get how this is hard to understand. I dont see a variable in this particular test scenario.

This isnt a coke vs pepsi test

Coke is better by the way
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