Klarinet Archive - Posting 000330.txt from 1998/01

From: Roger Shilcock <roger.shilcock@-----.uk>
Subj: Re: A440
Date: Wed, 7 Jan 1998 03:53:35 -0500

I think one has to ask: WHICH "tube frequency?" Furthermore, what happens
wth
multiphonics (intentional or otherwise)?
Roger Shilcock

On Tue, 6 Jan 1998, Douglas Sears wrote:

> Date: Tue, 6 Jan 1998 11:38:33 -0800 (PST)
> From: Douglas Sears <dsears@-----.org>
> Reply-To: klarinet@-----.us
> To: Clarinet People <klarinet@-----.us>
> Subject: Re: A440
>
> On Sun, 4 Jan 1998, J. Shouryu Nohe wrote:
>
> > I keep seeing this 'the reed vibrates 440 times a second' stuff...and I
> > have to say...huh?
> >
> > Are you SURE the reed vibrates 440 times when we play a concert A?
>
> Yep.
>
> > After
> > this years Musical Physics class, I find that unlikely. The statement
> > leads to a conclusion that the reed vibrates at different frequencies with
> > different notes; that most certainly is not the case. The reed vibrates
> > at a steady, constant frequency of something...I don't know what, but it
> > remains constant. Notes change due to the length of pipe that the air
> > vibratess within.
>
> Nope. There are simple systems, used for demonstrating physical
> principles, where the driving frequency is independent of the
> resonant tube, but a clarinet isn't one of those. A reed has a
> free-air frequency, but when it's on a clarinet, the pressure
> variations in the tube make the reed flap open and closed at the
> tube's frequency.
>
> > (There's some more stuff having to do with
> > wavelengths and whole odd intergers...but I already sold my book because I
> > didn't like the class, and am just happy to have passed it...actually, I
> > haven't checked my grades yet, so I don't know that I HAVE passed it....)
>
> Please let us know if you passed. I would've flunked you for that.
> :)
>
> --Doug
>
> --------------------------
> Doug Sears dsears@-----.org/~dsears
>
>