Klarinet Archive - Posting 000317.txt from 1997/09

From: Jonathan Cohler <cohler@-----.net>
Subj: Re: ending the GreenLine plastic/composite thread
Date: Sun, 7 Sep 1997 19:05:45 -0400

Roger Garrett wrote (in reference to some Backus citations from Mark Charette):
>These are extremely old references - and I view them as possibly
>unreliable sources.

The age of a fact has nothing to do with its factual status. They don't
change with age like wine. Facts are facts. Especially, experimentally
verified ones.

> Is anyone playing on a plastic flute or organ with
>plasic pipes?

I am sure there are people doing this, but it is not a relevant question to
the discussion at hand.

> Is there a difference between plastic recorders and wood
>recorders?

Nope. See my post on the subject.

>What about wood flutes and plastic flutes (such as the modern
>baroque flutes)?

Nope. See my post on the subject.

>I am also curious who did the listening - were they
>specialists on those instruments or laymen who work with plastics, woods,
>and metals?

I'm not sure which particular study to which Mark referred, but I do know
that Backus is one of the great physicists/acousticians of this field and
he regularly used the finest professional musicians as subjects for his
experimental work.

>Is there a more recent study with more reliable, up-to-date
>measurement devices?

There are no subsutantial conclusions from any of Backus' (or for that
matter any scientists') study that depended on measurements that fell
within the range of error of the measuring devices. If they did, they
wouldn't have been reported as results or conclusions. That is the nature
of scientific study and inquiry. Therefore, more precise measuring
instruments don't change any of his conclusions. And when you say "more
reliable", why do you assume that they are unreliable? Given that Backus
(as I said before) was a giant in the field (like Benade), and his work has
never been contradicted by any of the other subsequent giants in the field,
it seems silly of you to assume that the fundamental physics - developed
theoretically and verified experimentally - is "unreliable".

>What about any that are done with the composite
>plastics in question?

I believe these have been done by the same people mentioned above. But as
Greg Gallant pointed out, it does not matter that the plastic is a
so-called "composite plactic". What matters are its fundamental physical
properties such as porosity, heat conduction, density etc...

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