Computer model versus reality in a nonshoebox orchestra hall. Part I

Abstract

The Portland (Maine) City Hall Auditorium was the venue for acquisition of occupied and unoccupied acoustical data on 4 October 1994, using the MLSSA system. During intermission, an omnidirectional loudspeaker was positioned at center stage in the plane of the proscenium arch and occupied data were collected with nearly a full audience. Three volunteers equipped with eyeglass microphone‐pairs and DAT machines occupied six preselected seats in 3.5 min to acquire 18 binaural 64‐K impulse responses. The same seat locations were used earlier in the day to obtain the unoccupied data. An ODEON (c) computer model of this hall, created by Kirkegaard and Associates, is used to estimate acoustical parameters from the same source and receiver locations as used in the live audience acquisition. Particular attention is given to response features due to the design of this hall, which is a double‐balcony horseshoe‐shaped space with curved ceiling. [Work supported by the Concert Hall Research Group.]