Klarinet Archive - Posting 000488.txt from 1997/09

From: Jonathan Cohler <cohler@-----.net>
Subj: Re: ending the GreenLine plastic/composite thread
Date: Wed, 10 Sep 1997 01:52:28 -0400

Roger Garrett wrote:

>It is subjective to believe that a person decides, not by the blowing but
>by the feeling! The tester certainly does not know if the person can
>distinguish between them! A lot of talk about scientific process
>.....when the bottom line is, using the hands on a horn does in fact
>affect resistance of the air pressure. I certiainly would want to use my
>own fingers over the horn than rely on someone else's ....or a machine for
>that matter!
>
>Roger Garrett

Huh? Please translate into English.

I'll attempt to respond to those statements that I can discern from the above.

First, you say "the tester certainly does not know if the person can
distinguish..." This is nonsense. What do you mean?

Here's one way that the experiment can be done (there are others):

1 The player plays an instrument; he is not told which it is.
2 He plays another instrument; again he is not told which instrument
it is; and it might, in fact, be the same instrument.

3 The tester asks the player, "do these feel the same or different?"
4 Tester records response on a piece of paper.

Now repeat steps 1 to 4 a large number of times, in each case giving
the player in steps 1 & 2 either the same instrument or two identically
manufactured instruments made from different material (plastic &
metal for example).

Once all of this data has been recorded correlation calculations can be
done to see if the player actually discerned between the instruments made
of different material with any statistical significance. And so on...

So in conclusion, of course the tester certainly does know he asks!

Again, I'll repeat it for the umpteenth time, these experiments have been
done and they are fact NOT opinion.

Second, you say that "using the hands on a horn does in fact affect
resistance of the air pressure". Again this is nonsense, unless you are
referring to someone who doesn't cover the holes properly. And that is not
something I was discussing. A properly covered hole behaves the same way
no matter who is covering it.

Third, if the tester were allowed to touch the instrument during these
experiments, it would completely invalidate the experiments, because anyone
can feel the difference between plastic, metal and wood with their hands.
The entire purpose of the experiments is to determine whether or not there
is a blowing or sound difference. If the testers can feel the instrument
with their hands, their responses will be biased and useless.

------------------------
Jonathan Cohler
cohler@-----.net

>
> On Tue, 9 Sep 1997, Jonathan Cohler wrote:
>>
>> 1. Use the same mouthpiece/reed/ligature, with the same player
>> for all instruments.
>>
>> 2. Don't allow the player to touch the instrument. Have someone
>> else finger notes for him.
>>
>> Now, if the instruments have precisely the same blowing/sound
>> characteristics, the same player with the same setup will not be able to
>> distinguish between them (in any statistically useful way). This has been
>> demonstrated in experiment.
>>
>>
>> On the other hand, people may certainly convince themselves that things
>> sound or feel different when they, in fact. do not. But if they cannot do
>> this with repeatability in blind experiments then it is meaningless.
>>
>> And certainly, people are entitled to have aesthetic preferences (plast vs.
>> wood vs metal etc.).
>>
>> ---------------------
>> Jonathan Cohler
>> cohler@-----.net
>>
>>
>>