Klarinet Archive - Posting 000169.txt from 2007/09
From: "Doug Potter" <doug@-----.net>
Subj: RE: [kl] Blown out clarinets
Date: Sun, 23 Sep 2007 18:03:33 -0400
Yes, the primary source of moisture in your instrument is the condensed
water vapor from your breath. It likely has a small component of saliva -
but not very much.
I'm a little surprised that this discussion hasn't been more about what
"blow-out" actually is. If we look at how a clarinet produces sound, I
think the question should be what could possibly change that in turn changes
the sound?
There are a number of sites that discuss how a clarinet produces sound -
some that I know about are http://www.phys.unsw.edu.au/music/clarinet/ and
http://www.sfoxclarinets.com/baclac_art.htm - but a clarinet is basically a
stopped pipe closed on one end (where the mouthpiece is) and open on the
other (where the first tone hole is open or the bell). It's the motion of
the air in the pipe that produces the sound.
What's likely to change the sound? I think it's primarily the location and
size of the tone holes - and the shape of the mouthpiece. Less important is
the diameter and profile of the bore - although they are more important at
the ends (mouthpiece and bell) than in the center. And even less important
is the pipe's material.
So what's changing to produce a blown-out instrument? One could imagine
build up of "smutz" (love that word) on the tone holes or otherwise changing
the tone holes. I can also imagine moisture or lack thereof changing the
shape of the bore - and I suppose that could be significant in the barrel
area. I see as I write this that Kurt is suggesting the smutz is old
breakfast that can be cleaned out to make it all work better.
So I am more or less in Dan's camp on blow-out being rare or non-existent.
Nevertheless, my local oboe professional swears he has to replace his oboe
every few years because it's worn out (I forget if he uses the term
blown-out). I've never been able to get a coherent explanation of what that
means. A oboe has a conical bore - and is probably much more sensitive to
variations in the bore size and shape where the bore is small (near the
reed). But with lack of any more information, this is sheer speculation on
my part.
I've also thrown out the sure to be controversial notion that the material
that the instrument is made of is not very important. I know some of you
support this - but others do not. I suspect that in today's world, there
are materials that work better than wood - because they are more stable
under wear and moisture. No one uses a wood mouthpiece any more.
Doug
http://ConicWave.net
-----Original Message-----
From: John Dablin [mailto:jdablin@-----.com]
Sent: Sunday, September 23, 2007 2:28 PM
To: klarinet@-----.org
Subject: Re: [kl] Blown out clarinets
Just a thought: someone suggested some speculative reasons for so
called "blow out", including the effects of saliva on the wood. Now
I know full well that if any amount of saliva gets behind my reed
the result is a disastrous "frying" sound, so I think it extremely
unlikely that saliva gets any further than the mouthpiece, if it
even gets that far. I think it's extremely unlikely that it can
travel far enough to affect the wood. Surely the moisture we swab
out of our instruments is the result of water vapour in our breath
condensing as it cools while travelling down the instrument?
John Dablin
Aylesbury UK
------------------------------------------------------------------
------------------------------------------------------------------
