Klarinet Archive - Posting 000263.txt from 1996/10

From: Mark Charette <charette@-----.com>
Subj: CO2 and Pitch
Date: Thu, 10 Oct 1996 18:12:54 -0400

I've been following the CO2 and pitch change discussion and have just
one thought.

Most of the assumptions on pitch change concerned the CO2 in the
clarinet air column changing the density. In reality, the amount of
air expelled to produce a tone for a relatively short time is
significantly smaller in volume than the air column contained in the
clarinet. Therefore, diffusion of the CO2 over time would have to be
taken into account, along with the effective length of the clarinet
air column (which depends on the holes covered and exposed for the
note). The pitch should change over time, given a perfectly "fresh"
air column, a perfectly still embochure, and a perfectly consistent
air stream. Anyone have a clarinet playing machine ? ;^)

Just as a point of reference, a friend who skokes and plays trumpet
showed dramatically how long it takes for smoke to diffuse along
the tubing of a trumpet being played in a jazz band. It took MUCH
longer than I expected to come out of the horn.
--
Mark Charette "There's one dead cat in every bar of Dead Cat Soap"
charette@-----.com - Firesign Theater