Klarinet Archive - Posting 000328.txt from 1998/01

From: Jonathan Cohler <cohler@-----.net>
Subj: There's no need to wonder...
Date: Wed, 7 Jan 1998 00:17:51 -0500

Boy there sure are a lot of messages about this subject of how the reed
vibrates. Many of these have contained much of the basic correct
information. But many others are just plainly incorrect (I didn't use the
word wrong, Roger, are you proud of me?! :-))

Anyhow, there is no need to debate or wonder about it. This is a simple,
totally documented, matter of physical fact verified by theory and
experiment.

1. The clarinet is basically a coupled vibrating system with two
components: the reed and the air column. Independently, these
two elements have their own preferred modes of vibration. Coupled
together they vibrate in cooperative "regimes of oscillation".
As has been described by others, it is precisely the pressure
vibrations of the air column that suck the reed toward
and away from the mouthpiece causing it to vibrate.

Therefore, the reed definitely vibrates at the same frequency
as the air column under normal playing conditions. This is
all described in great detail by Benade in "Fundamentals of
Musical Acoustics".

2. The reed does not hit the mouthpiece at soft dynamics.

3. The reed does hit the mouthpiece producing total closure at
louder dynamics. The amount of time during each cycle that the
reed is totally closed gets larger at the loudest dynamic levels.

That's how the story goes...

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