Home Journal
E-mail Print
Acoustics Australia Logo (3032 bytes)

Vol 27 No 1

CONTENTS

April 1999


ARTICLES

Materials for Musical Instruments
Neville Fletcher
PDF Full Paper

Design of Chimes to Produce Consonant, Non-Harmonic Scales
Arthur Gretton
PDF Full Paper

Noise Reduction for Sheet Metal Industry Achieved with Automatic Stacker
M.A. Burgess, C. Speakman and H.M. Williamson


PDF Full Paper

Books
Australian Acoustical Society Code Of Ethics
News
New Members
New Products
Diary
Acoustics Australia Information
Australian Acoustical Society Information
Advertisers Index


Materials for Musical Instruments

Neville Flelcher
Research School of Physical Sciences and Engineering
Australian National University
Canberra 0200

Vol. 27, No. 1 pp 5-9 (1999)
ABSTRACT: The relation between musical instruments and the material, from which they are made is discussed. In most cases the particular malerial used was originally dictated by availlability or by technological necessity - only wood was suitable for the bodies of stringed instruments, only tin-lead alloys could he made into organ pipes, only bronze could be cast into bells - but this fact then determined the way in which these instruments evolved. Today the choIce of mayerials is almost limitless, but often nothing better than the traditional materials has been found. The technological and, where appropriate, the acoustical basls for this situation is discussed.

Design of Chimes to Produce Consonant, Non-Harmonic Scales

Arthur Gretton
Department of Engineering,
Australian National University, Canberra 0200

Vol. 27, No. 1 pp 11-16 (1999)
ABSTRACT: Thin, cylindrical metal chimes can be used to play in a variety of scales requiring non-harmonic spectra The speclrum required for the chimes to have consonant intervals in a given non-harmonic scale can be determined accoording to a method developed by Sethares, based on the theory of dissonance proposed by Plomp and Levelt. First order perturbation theory was applied to control the frequencies of the first six modes of a thin, cylindrical metal chime by perturbations to the chime radius. The resultant chime profile was then refined using finite element methods. Two aluminium chimes manufactured with this optimised profile demonstrated superior musical performance compared with unperturbed thin cylinders.

Noise Reduction for Sheet Metal Industry Achieved with Automatic Stacker

M A Burgess1, C Speakman2 and H M Williamson3
1Acoustics and Vibration Unit, University College,
University of New South Wales, Australian Defence Force Academy, Canberra, ACT Australia 2600
2Sound Control Pty Ltd, PO Box 849 Hamilton Central Qld Australia 4007
3Hugh Williamson Associates Inc., 12 Maple Lane, Ottawa, Ontario Canada

Vol. 27, No. 1 pp 17-19 (1999)
ABSTRACT: The aim of this study was to demonstrate the noise reduction which could be achieved in a roll formed sheet metal production line when manual handling was replaced with automatic stacking. The handling noise was generated when finished sheets of profiled thin metal were moved from a runout table, and placed or droppod onto a stack. Sources of noise included impact or sliding contact between the produst and parts of the machinery, and impact or sliding contact between product pieces. Considerable noise is normally generated when product is dropped from a height onto a stack or the floor. While the primary incentive for the automatic stacker was to reduce the risk of back injury by eliminating much manual material handling, the noise exposure for the operator was also reduced with little additional cost by careful consideration at the design and implementation stages for the project.

 

Newsflash

PROPOSED INTERNATIONAL YEAR OF SOUND 2019

Let's make 2019 the International Year of Sound!

Click here to see draft prospectus. Suggestions for major activities that would be truly international to strengthen the application are welcomed.

 

ACOUSTICS 2017

Perth, Western Australia 19-22 November 2017