Klarinet Archive - Posting 000495.txt from 1995/09

From: Everett J Austin <BrendaA624@-----.COM>
Subj: undertones controversy
Date: Sun, 24 Sep 1995 17:39:19 -0400

I must say I have enjoyed the rather heated comments arising from the mere
mention of undertones, and wanted to add a couple of comments.

Beware of clarinetists bearing equations. I would like to point out an a
single inaccuracy in Mr Cohler's recent communication in which he refers to
Benade's Fundamentals of Musical Acoustics and also to work done by Backus
described therein:

"They also noted (and this is key) that as you reduce the pressure of the
embouchure against the reed, the airflow reaches its maximum at a lower
pressure P-p, and the reed finally closes off at a lower pressure. Also,
the maximum airflow reached is lower."

Actually, Figure 21.4 on page 437 of Benade's book illustrates just the
opposite finding, ie, that the above obtains for the tighter not the looser
embouchure. Benade's text states this on the same page as well: "we also
notice that tightening the embouchure reduces the blowing pressure required
to close the reed completely".

It is also interesting to read Backus'account in his own book, The Acoustical
Foundations of Music (Norton). This illustrates the fact that for the
physicist it is most convenient to reduce the player to a first order
approximation, something that blows and squeezes the reed, producing a sound
of the correct pitch from the clarinet, otherwise the situation becomes too
complicated to analyze: "a box sealed to and enclosing the mouthpiece and
connected to an airsupply under pressure. A piece of soft material is
mounted in the box and pressed against the reed to simulate the player's
lip...(such a tone becomes very irritating after a while)"

These are interesting and illuminating books to read, but so far no one has
learned to play and instrument well solely from a physics book!

I would suggest that these experimental observations do not really settle the
controversy that seems to have been stirred up, perhaps because they involve
such a simplified system and perhaps because some people actually play the
clarinet differently and perhaps because some people feel and interpret
physically what they are doing differently. First, there are in fact
different schools of sound production and secondly, human anatomy is more
complicated that the pressure device of the Backus experiments. One comment
in particular by Benade really leaves the door open for a lot of different
ways to get similar results: "the player can trade off blowing pressure for
embouchure tension in many combinations"

Another simplification of the discussion which should be pointed out is that
the mouthpiece-reed aperture is the only site of resistance in the system.
This is the point of view taken by one school of playing, well illustrated
in a book by Lefebvre and Goffin, "De La Technique du son dans les
instruments a anch battante" published by A Leduc, Paris. These authors
advocate all compensations be made basically as complementary variations in
air and in embouchure pressures to get the desired pitch and loudness. (See
the section "Theorie des son files" on page 22) They go on to point out that
this only works well with the best reeds. A different pedagogical appproach
advocates the manipulation of the airsteam/airspeed as the primary variable,
gives less emphasis to embouchure manipulation and strives to give the reed
the most freedom to vibrate without loss of control. I believe that these
individuals tend to be more aware of internal factors such as laryngeal
resistance and tongue position and therefore conceive and feel "airflow and
airspeed" as something being fed into the instrument from their body and not
conceive it as the measurement of airflow through the tiny aperture between
the reed and the facing of the mouthpiece as a physicist would prefer to view
it. (I might add that these concepts are very familiar to most classical
saxophone players.)

As in many controversies, both sides are ultimately right in one way or
another. I suspect that people coming from either camp and playing well may
be drawing their resources unconsciously (or consciously and thereby bending
their own rules) from both sides of the fence.

Sincerely,

Everett Austin, MD
single reed enthusiast
SF