Avaliação do condicionamento acústico de um cinema com absorvedores ressonantes: estudo de caso

Abstract

This study evaluates the acoustic conditioning of a cinema equipped with resonant absorbers—specifically perforated panels—through simulations and measurements of objective acoustic parameters. The research focuses on the importance of adhering to the air cavity (plenum) specifications used in sound absorption coefficient tests, as the actual application of the coverings did not follow these guidelines, resulting in discrepancies between simulated and measured values. The analyzed cinema, located in Guarapuava-PR, has a volume of 221.1 m³ and uses MDF perforated panels on the walls and ceiling, with different air cavity configurations. Simulations were performed using the Raven software, while impulse response measurements followed the ABNT NBR ISO 3382-1 (2017) standard. The results showed that the measured reverberation times at 250 and 500 Hz were within the limits recommended by the ABNT NBR 12179 (1992) standard, but diverged at higher frequencies. The main conclusion is that acoustic conditioning design will only be effective if the air cavity thicknesses are respected according to the sound absorption tests, highlighting the importance of aligning practical execution with design assumptions.