Klarinet Archive - Posting 000124.txt from 2009/09
From: Diego Casadei <casadei.diego@-----.com>
Subj: Re: [kl] Antique clarinet length determines diapason?
Date: Sun, 27 Sep 2009 15:02:26 -0400
Dear Simon,
the best way to determine the natural tuning of an instrument is to look
at the holes that make known intervals.
For example, 1 octave means that the wavelength of the lower note is
twice of the wavelength of the higher pitch. The implication is that
the holes should mark distances to the (almost) fixed position of the
first node (*) which are a factor of two apart. By taking into
considerations other intervals (different octaves, fifth and fourth
intervals) one can build a histogram of the position of the first node.
Finally take the mean of the histogram as the best estimate of its
position and recompute all wavelengths, to find the diapason.
(*) If I remember correctly, the clarinet has a (almost) fixed node at
some distance from the mouthpiece (upper region of the barrel). This
distinctive feature is useful in your case. Other details on the
clarinet acoustics may be found on
http://conicwave.net/Clarinet/index.php (in addition to the many good
books on the clarinet that I'm sure you know).
I hope my (very) short summary is clear enough to give you some useful hint.
Best regards,
Diego
Simon Aldrich wrote:
> In the murky world of determining an antique clarinet's diapason (A430,
> A435, etc) is length of the instrument any sort of indication of its
> possible diapason?
> Specifically I am thinking of an 1860 boxwood Lecomte 13-key clarinet of
> 20 inches (without mouthpiece).
> Many sellers don't know the diapason (let alone the key) of the clarinet
> they are selling.
> In such a situation, is the length helpful in determining
> characteristics of the instrument such as its key and possibly diapason?
>
> ------------------------------------------------------------
> Simon Aldrich
>
> Clarinet Faculty - McGill University
> Principal Clarinet - Orchestre Metropolitain de Montreal
> Principal Clarinet - Orchestre de l'Opera de Montreal
> Artistic Director - Jeffery Summer Concerts
> Clarinet - Nouvel Ensemble Moderne
>
> ------------------------------------------------------------------
>
--
Diego Casadei, PhD.
Physics Department, CERN
New York University bld. 32, S-A19
4 Washington Place 1211 Geneve 23
New York, NY 10003 Mailbox J28310
USA Switzerland
office: +1-212-998-7675 office: +41-22-767-6809
mobile: +39-347-1460488 mobile: +41-76-213-5376
http://cern.ch/casadei/ Diego.Casadei@-----.ch
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