Keith Ballagh

Keith Ballagh Emeritus

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

Qualifications & Memberships

  • Bachelor of Engineering (Mechanical) 1st Class Honours, University of Canterbury
  • Member of NZ Acoustical Society (Past President)
  • Member of the American Acoustical Society


Sound insulation of timber framed structures Accompanying presentation to 'Sound insulation of timber framed structures' Accuracy of Prediction Methods for Sound Transmission Loss Prediction of Acoustic Performance of Composite Steel Floors

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