Keith Ballagh is a Principal of Marshall Day Acoustics, working out of the Auckland office.

Keith Ballagh graduated from the University of Canterbury in 1974 with first class honours in Mechanical Engineering, joining the Acoustics Section of the Department of Scientific and Industrial Research as a Scientist and in 1981 was appointed Section Leader. 

In 1981 he worked at the Physikalisch - Technische Bundersanstalt in Braunschweig, Germany, one of the worlds leading acoustic research centres.

Keith joined Marshall Day Acoustics in 1987 and became a partner in 1995.  His work has included the full range of acoustical consulting work, from room acoustics to industrial noise control and environmental impact studies.

Keith developed INSUL sound insulation software and Zorba for predicting absorption performance of systems both of which have sold in more than 30 countries throughout the world and are in use by universities, consultancies and manufacturers.

Recent project experience includes:

:: SH18 Greenhithe noise mitigation design

:: WEL Energy Trust Academy of Performing Arts at the University of Waikato

:: House insulation programme for Port Otago

:: Tauranga Eastern Motorway - noise modelling

Publications

:: 1977    Balachandran, CG & Ballagh, KO "Stationary Test Method for Noise from a Single Road Vehicle" Applied Acoustics 10, 1077

:: 1982    Ballagh, KO "Limitations to the measurement of sound power by the reference sound source method", Journal of the Acoustical Society of America 72, 1982

:: 1983    Ballagh, KO "Optimum Loudspeaker Placement near Reflecting Planes", Journal of the Audio Engineering Society 31, 1983

:: 1984    Ballagh, KO "Qualifications Tests in a Hemi-anechoic Room", Acustica, Vol 54, 1984

:: 1986    Ballagh, KO "Calibration of an anechoic Room", J.Sound and Vibration 105, 1986

:: 1987    Ballagh, KO "Acoustical Admittance of Cylindrical Cavities", J.Sound and Vibration 117, 1987

:: 1990    Ballagh, KO & Corney, ACC "Some Developments in Automated Microphone Calibration, Acustica,  Vol 71, 1990

:: 1990    Ballagh, KO "Noise of Simulated Rainfall on Roofs", Applied Acoustics Vol 31, No. 4, 1991

:: 1993    Ballagh, KO "Investigations into Hygenic Attenuators", Applied Acoustics Vol 40, 1993, 107.

:: 1993    Ballagh, KO "Acoustical Properties of Wool", Applied Acoustics - to be published.

:: 1995    Ballagh, KO "A Theory of rainfall noise", Applied Acoustics - to be published