Recent Progress in Room Acoustical Computer Simulations

Abstract

In the last decade computer simulations of sound fields in rooms have been developed for application in research and consulting. Some programs are commercially available. Most computer models are based on geometrical room acoustics and/or on statistical (radiosity) methods, thus not including wave phenomena such as diffraction. The uncertainty of typical simulation software was investigated in an international verification test in 1994 and 1995. The results were partly promising although some programs were not as reliable as the operators expected. These round robin tests have been continued until today with simulations and measurements in a concert hall in Jönköping in Sweden. In this paper the basic algorithms of room acoustical computer simulations, the verification in round robin tests and the observed accuracy and limitations are summarised. Finally, possible improvements are discussed.

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