Klarinet Archive - Posting 000218.txt from 2001/12

From: "Keith" <100012.1302@-----.com>
Subj: [kl] RE: klarinet Digest 9 Dec 2001 09:15:00 -0000 Issue 3502
Date: Sun, 9 Dec 2001 16:20:25 -0500

Clark,

---------
Date: Sat, 8 Dec 2001 20:32:28 -0800
From: "CLARK FOBES " <reedman@-----.com>
Subject: Materials
Message-ID: <001701c1806a$828c3540$831efea9=computer>

>>Thanks Keith for presenting the material form Benade in a very thoughtful
and lucid manner.

:-)

>>I have Benade and have read certain portions of the book many times. I
also
own Lee Gibson's book which is much less scientific and often haphazardly
written, in my opinion. He does offer some valuable information on the
development of clarinet bores and clarinet design.

I fully agree!

>>As I read both of these recognized masters of instrumental acoustics I
have
often wondered how much of their information is derived from theory and how
much from practical experience. Benade is beyond reproach in his thorough
scientific study of musical instruments and he was apparently a competent
amateur clarinetist (As was John Backus - a little easier to get through).
Gibson is a very accomplished clarinetist and acoustic dabbler. But, I doubt
that either of these men has made very many mouthpieces, barrels, bells or
instruments from the ground up. They lack the experience of the artisan. I
think of these men as masterful art critics that have analyzed the process
of painting down to the molecule, but have never produced a painting and
experienced the wonderful, organic process of art.

I don't know about Gibson, but Benade was certainly a detailed experimenter.
He worked more on modifications to instruments (tone holes, bore shape etc)
but certainly made many basic experiments on whole instruments. He was
responsible for the innovative FX bore design and made a prototype, which
Stephen Fox has now incorporated into some of his clarinets.

>>My point is this. As a maker of acoustical parts for clarinets it is my
experience that,
>>a.) materials do have an influence on sound (Smoothness, or skin friction
and porosity) and
>>b.) wall thickness or perhaps overall mass DOES influence the performers
perception of sound and response.

Yes, this is in accord with Benade's evidence. I think it's also an
interesting question how far the performer's perception is mirrored by that
of the outside listener (who does not have the bone conduction component of
listening, which must introduce some distortion).

>> To return to my point about wall thickness. Clarinet barrels have very
thick walls when compared to a flute. Yet, if I remove wood near outside at
the top end of the barrel the sound is distinctly different than if I leave
that area alone. I am certainly not affecting the interior in any way. The
material of the rings makes a subtle difference. Barrels with a pronounced
"bulge" respond differently than barrels that have none. Have you ever
wondered WHY all clarinet barrels have a bulge? Benade (and many others) may
say that the result is not measurable in any way. But it is measured by the
performer in the way she feels the tone being produced.

>> Here is a simple experiment. Buy some lead tape at a golf shop (used
for
weighting clubs) and put a 1 inch piece on your barrel. Try it on your bell.
You will find that there are very subtle influences at work here. These are
not topics that seem to interest the acoustician. These subtleties,
sometimes immeasurable and intangible are in the realm of art. Sorry, Dan!

You are quite right and Benade did measure effects of wall thickness and
also performed experiments similar to the tape. He used PVC tape on flutes,
but the idea is the same as lead tape on clarinets. His interpretation
(around page 500) is that this is a modification of the air column
vibrations, by interaction of the body vibrations.

But I come back to the point that we do not yet know enough about the theory
to use it for complete clarinet or mouthpiece design. It gives us some
pointers, and can eliminate some blind alleys, but craft and experience
still reign supreme (that's why I asked you to make me a mouthpiece for my
contrabass!). As I said to Walter, I am sure that experienced instrument
makers can give scientists all sorts of ideas and conjectures that can then
be examined and tested.

Keith Bowen

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