| Vol 30 No 3 | CONTENTS |
December 2002 |
Bandicoot --- A Novel Approach to using a Pitch-Catch
Acoustic Probe for Field Non-destructive Testing
L.P. Dickinson and S. Thwaites
Improved Noise Management for the Building Industry
M. Burgess and J. Lai
Recording the Operatic Voice for Acoustic Analysis
D. Cabrera, P Davis, J. Barnes, M. Jacobs and D. Bell
Condenser Microphones -- A Tutorial
N. Fletcher
Road Traffic Noise -- the Selection of a Preferred Route
Neil Gross
Book Reviews
AAS Council
Future Meetings
Meeting Reports
New Members
Standards Australia
FASTS
Letters
New Products
Diary
Acoustics Australia Information
Australian Acoustical Society Information
Advertisers Index
Vol. 30, No. 3 pp 93 - 96 (2002)
ABSTRACT: The acoustic Pitch-Catch probe is commonplace in the world of aerospace non-destructive testing for the location of defects
within a composite sandwich panel. However the usefulness of the technique is lacking in many respects, being cumbersome to use and
generally very costly. Building on several years of experience, a new approach has been taken by CSIRO to produce a simple and versatile
system that incorporates an optimised Pitch-Catch probe within an optical computer mouse and combined with a notebook computer, to
provide a fully featured scanning system for a fraction of the cost of systems currently available. This paper describes the approach taken
and some of the underlying research in developing the Bandicoot.
An earlier version of this paper was presented at the 2001 AAS Annual Converence, Canberra, November 21-23, 2001
Vol. 30, No. 3 pp 97 - 101 (2002)
ABSTRACT: There is great potential for excessive noise exposure for workers in the general building industry as not only can the
individual tools and equipment produce high noise levels but also the worker is usually close to the source of the noise. Effective noise
management procedures are required to minimise the loss of hearing of workers on building sites. This paper reports on a project sponsored
by WorkCover NSW for which the aims included identification of a baseline of current noise exposure levels on a representative range of
building sites, assessment of the extent of the implementation of noise management codes on building sites and suggestions for strategies
for improved implementation.
Vol. 30, No. 3 pp 103 - 108 (2002)
ABSTRACT: This paper considers a number of factors related to the recording of the voices of operatic singers for acoustic analysis. We
wanted to develop a technique for recording these singers in non-anechoic environments so we tested head-mounted microphones. We tested
their effectiveness in recording the direct sound produced by the singer with relatively little interference from the reflections of the sound
in the recording environment. We examined the effectiveness of various near-field microphone positions using a head and torso simulator
in anechoic conditions and applied these observations to recording an operatic soprano, comparing the head-mounted and reference
microphones. We also determined, that, for this singer, there was appreciable movement of the head and body during operatic singing, even
when the singer tried to avoid moving.
Vol. 30, No. 3 pp 109 - 113 (2002)
ABSTRACT: This tutorial discusses the operation of several types of condenser microphone including standard omnidirectional
measuring microphones, simple cardioid microphones, and studio microphones with adjustable response pattern. The physics underlying
their operation is discussed, and the approach to a detailed analysis using electrical network analogs is outlined.
Vol. 30, No. 3 pp 115 - 116 (2002)