Klarinet Archive - Posting 000149.txt from 1995/02

From: Timothy Tikker <tjt@-----.ORG>
Subj: Re: Caution More Physics!
Date: Tue, 7 Feb 1995 13:04:52 -0500

On Tue, 7 Feb 1995, Jon Delorey wrote:

> Speaking of boundary conditions, there was a posting a while back that stated
> the harmonics in an organ pipe were dependent on position. Would this be due
> to the proximity of the floor or ceiling, and is this a factor in the
harmonic
> output of a clarinet?

You must be referring to my posting about organ reed pipes (flue pipes,
which work much like recorders/whistles, behave quite differently).

I assume that the test I referred to was done in some lab or studio which
was as acoustically neutral as possible. However, whatever ceiling is
above and organ pipe does make a difference: hard and reflective vs.
soft and absorptive, flat vs. angled, high vs. low, etc.

The horizontal placement of a reed pipe allows the highest harmonics to
reach the ear more directly. When the pipe is aimed vertically, many of
those harmonics are lost. The situation with a Clarinet is a little
different, in that, except for low E and its overblown B, the tone leaks
out the holes in the sides as well, something which doesn't happen in an
organ pipe (except for the little tuning/voicing scroll at the top, if
the pipe has one). But certainly, playing under different ceilings, or
over different floors (hard vs. carpeted) will make a real difference in
the presence of tone.

We organists fight a frequently losing battle over the choice of
materials in a church - so many people want carpet, which destroys
acoustics.