Klarinet Archive - Posting 000149.txt from 1998/01

From: Douglas Sears <dsears@-----.org>
Subj: Re: swabbing really does wear it out (retransmitted)
Date: Tue, 6 Jan 1998 08:17:14 -0500

On Sun, 4 Jan 1998, Roger Garrett wrote:

> On Sat, 3 Jan 1998, Bill Hausmann wrote:
> > "The motion of the reed during the cycle is of interest. Consider the
> > chink is just on the point of closing. With the aperature closed, the reed
> > appears motionless to the eye for about half of the time of the complete
> > cycle. It then leaves the mouthpiece with relatively high velocity and
> > reaches its position of maximum displacement in a series of short spurts.
> > The time spent motionless at maximum displacement is roughly a quarter of
> > the fundamental period. The tip of the reed now returns to the mouthpiece
> > in a series of short spurts, and the fundamental cycle is complete. Thus,
> > the actual motion of the reed occupies only about a quarter of the period."
>
> This experiement is dependent upon a person who closes the reed off
> against the mouthpiece. When I tongue (and when many tongue for that
> matter), the reed is closed off at the top....that is, the reed is not

Roger, I think you misunderstood. The cycle in Bill's quote is not
referring to the starting and stopping of a tongued note. It refers
to the reed vibration which produces a continuous tone -- so, for a
440 Hz note, the cycle in question happens 440 times per second. I
think the point was to prove that the reed does in fact bang into
the material of the mouthpiece (although I question how relevant
that is to a debate on abrasion, since there's no sliding friction
involved).

--Doug

--------------------------
Doug Sears dsears@-----.org/~dsears