Assessment of acoustic models of the National Theater of Costa Rica: towards an improved acoustic shell design

Abstract

The objective of this work, shared in this communication, was to compare the results of acoustic models simulated in COMSOL Multiphysics for the Stage and the Great Hall of the National Theater of Costa Rica (TNCR) with the parameters measured on-site and to propose improvements to the current acoustic conditions. The TNCR stage has an acoustic shell that is placed for live musical performances. This research evaluated the acoustic parameters through simulations based on three CAD models: without acoustic shell, with the acoustic shell that the TNCR currently has, and with an alternative acoustic shell proposal. The methodology included simulation of the sound distribution and calculation of the acoustic parameters T20, EDT, C80 and D50. The results of the models with and without shell were compared with measured values. The proposed acoustic shell was compared to determine its impact on the parameters. The results showed that the values of T20 and EDT tended to be overestimated, especially at low frequencies, while C80 and D50 showed agreement with the measured values. The proposed acoustic shell increased T20 and EDT without greatly altering C80 and D50. However, although T20 increased, it remained below the recommended range of 1.4 s to 1.8 s. As future work, new simulations should be run with different materials that reflect the sound even more and with different geometries that direct the sound more directly to the audience.