[Trombone-l] Glass Trombone (UNCLASSIFIED)

[Richardson, Timothy A Mr CIV USA IMCOM]

Classification:  UNCLASSIFIED 
Caveats: NONE

There are several studies summarized here: "Proceedings of The Institute of Acoustics Vol.8 Part 1 (1986) - Traduction en français 

The effect of material in brass instruments: a review.

Richard Smith
Richard Smith (Musical Instruments Ltd), 110 The Vale, London, N14 6AY"

You can see it's a bit dated, but there's lots of older stuff out there too.

  The reference to lead comes from the Schilke site but that one is suspect for a number of reasons.  It's all anecdotal (no references or documentation) and it's translated, English is not his native language.  He reports that a trumpet made of lead produced a pure sine wave which was an unusably bright tone - obviously a contradiction.  The technique with which he measured the sine wave could not have done so.  So there's just no way to know if it's a memory problem, a translation problem, or something else.

The reference to concrete comes from the Conn studies, which also seem to lack any documentation.    

-----Original Message-----
From: Dick Sleeman [mailto:dick at sleeman.nl] 
Sent: Monday, July 14, 2008 11:29 AM
To: Trombone-List
Subject: Re: [Trombone-l] Glass Trombone

Stuart wrote:

>I seem to recall reading a study that investigated best material for trumpet
> bells, which tested a variety of metals, as well as crystal and a few other
> things.  Apparently the best acoustical choice was lead!  I'll see if I can
> find the reference again.

Me too, I recall it was about three identical Aïda trumpets, one made of glass,
one wooden and one brass. They were played with the same MP by a professional
trumpet player behind a curtain, so the public couldn't see. The outcome was
that there was NO difference in sound. Apparently it is the shape of the column
of air that makes the sound (I thought it was in Benade, "Fundamentals of
Musical Acoustics" or in Backus, "The Acoustican Foundations of Music").

Classification:  UNCLASSIFIED 
Caveats: NONE