Klarinet Archive - Posting 000608.txt from 2004/10

From: "Keith" <100012.1302@-----.com>
Subj: [kl] RE: Some more thoughts on embouchures
Date: Thu, 21 Oct 2004 16:54:03 -0400

Ormondtoby,

>Keith Bowen wrote:

>> It is the vibration of the whole reed, driven by air pressure, that
>> excites the air column in the clarinet into oscillation and hence
>> produces the sound.

>Ormondtoby wrote:

>Keith, how would a lay reader interpret the word "excite"?

Sorry if this was a bit jargony. As well as Forest's "change in state"
(true, though "state" is a pretty technical term here), I'd add
"Stimulates", "causes", "couples to and generates"

>Would such a reader be sidetracked toward the false conclusion that the
reed is
>somehow fanning the air, rather than shaping the puffs of air that enter
the mouthpiece?

What a reader might be sidetracked into is always a mystery, but I don't
think either of these is a good description. In a fan (reciprocating, not
revolving), the air is propelled along the length of the blade. I agree this
is wrong. I don't know what "shaping the puffs of air that enter the
mouthpiece" really means or what relevance it has. Shaping in duration? In
pressure? How does this relate to clarinet sound? And I don't think the word
"puff" is helpful, since it detracts from the role of pressure variations in
causing the reed to vibrate.

I don't really think that the air entering the mouthpiece has much relevance
OTHER THAN its role (through pressure difference) in setting the reed
vibrating in the appropriate way. The flow of air through the clarinet is
not relevant to its sound production OTHER THAN the influence it has on the
vibration of the reed. I understand phrases such as "fast air", "spin the
air", "shapes of the puffs" to be metaphors that may help get the desired
vibration, without much physical reality. I'm prepared to listen to a
contrary argument (not to a mere opinion).

On my narrow-bore basset horn, I am very conscious of the feeling that one
is just setting up the vibrations at the top of the column, rather than
blowing into the instrument, which the bass and soprano instruments feel
like. Dan, do you agree? And of course, oboe players know that the flow of
air is not very relevant, as they keep having to stop to breathe OUT.

>Ormondtoby,

>Forest Aten wrote

>Excite - might be considered a change in state....

>A simple place to learn the fundamentals:
>http://www.glenbrook.k12.il.us/gbssci/phys/Class/sound/soundtoc.html

>Adam....go to 'pressure wave' and find a nice reference to Keith's tuning
fork example.

That's a great website for the fundamentals, with good illustrations.

Keith Bowen

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