Re: The effects of chemicals on intonation

Hi Jessica,

I'm copying my reply (including your original email) to The Alternate
Tuning Internet Mailing List (more info at
<http://www.pacificnet.net/~nowitzky/tuning>).

At 07:56 PM 11/23/99 EST, you wrote:
>Hello. My name is Jessica and I am doing a science/math project. I am study
>how different chemicals applied to clarinet reeds affect the intonation of
>notes. I was searching on the net for some information about intonation,
>where I happened to come across your website. It had a lot of information
>that was interesting, but only a little amount that was applicable to my
>project. In my experiment, I used 4 size 3 V12 Vandoren Bb clarinet reeds. I
>played a Concert Bb with all 4 of the reeds and recorded the intonation off
>of my automatic chromatic tuner set on 440 as the pitch. I soaked a reed in
>orange juice, another in vinegar, the 3rd in vegetable oil, and the last in
>sugar water. I allowed them to be immersed for 5 minutes. I took them out
>and let them dry, and then I played the Concert Bb again. I took the initial
>and final readings and compared the change. The results were that the
>vinegar affected the reed the most. I'm not sure if this is part of your
>expertise, for this project is kinda "different", however, i was wondering
>if you could tell me what causes the intonation fluctuations with the added
>substances and if there is a more accurate way of calculating the intonation
>changes besides subtracting the initial and final readings off of the tuner.
>If and when you have time, i would greatly appreciate your reply. Thank you
>very much. :)
>
>Sincerely,
>
>Jessica
>11th grade student
>Lyman High School
>Longwood, FL

I'm not much of a reed player myself, but I would imagine that if soaking
the reed in different liquids caused intonational changes, they'd just be
compensated for in practice by adjusting the length of the "tuning barrel"
(or whatever it's called, we trombonists call it a tuning slide).

I presume that as you're changing reeds in your experiment, you're being
careful to put the mouthpiece/barrel back on in the same tuning position
(perhaps fully closed/shortened). I guess a thicker reed might cause the
clarinet to appear slightly shorter, resulting in a slightly higher pitch.
So if soaking the reed made it thicker, maybe you'd get a higher note.

Your experiment may also result in changes in "timbre", maybe causing less
of a "clarinetty" sound. But your tuner won't help you measure that.
Clarinets are almost the only instrument whose "frequency spectrum" has
only odd harmonics (it skips the even harmonics because the tube is closed
at one end). This give clarinets that "oo" sound (as in mOOn).

Regarding your method of calculating the intonation changes, it would make
more sense to divide your readings instead of subtracting them, since pitch
is geometric rather than arithmetic. For example, to go up an octave, you
double the frequency. "Cents" are commonly used as a unit of measurement
for intervals; 1200 cents = 1 octave.

Anyway, perhaps some of the tuning list folk can better assist you. Many
of them are performers, some of them are instrument builders. And your
topic sounds relevant to expermental musical instrument design.

Good luck (and happy T-day)!
--Mark (nowitzky@alum.mit.edu, AKA tuning-owner@onelist.com)

+------------------------------------------------------+
| Mark Nowitzky |
| email: nowitzky@alum.mit.edu AIM: Nowitzky |
| www: http://www.pacificnet.net/~nowitzky |
| "If you haven't visited Mark Nowitzky's home |
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