Scale modeling in architectural acoustics

Abstract

Several types of models are available to the acoustician for the study of room acoustics. Although mathematical modeling has now become popular, due to recent advances in computer technology, the author chose to use scale modeling techniques. A 1:10 scale model was constructed to study the sound field above the audience in a large lecture hall. A steady-state jet sound source was developed to model the standard ILG reference sound source. A model of unoccupied audience seating was designed and constructed and a new approach to air absorption compensation was used. A data acquisition procedure was developed for easy and accurate comparison of data taken in both the model and the full-scale lecture hall. Verification of the model was carried out with measurements of both reverberation time and steady-state sound levels. This scale model continues to provide a useful tool for the study of sound propagation over audience seating. It also enables simple modifications to determine the dependence of the reverberant field on both the magnitude and placement of absorption within the enclosure.