ACOUSTIC EVALUATION OF A FM RADIO STUDIO BASED ON MEASUREMENTS AND MODAL ANALYSIS

This article investigates the main acoustic parameters of the FM radio studio of the "Casa da Comunicação" of the Federal University of Santa Maria. The results related to the acoustic conditioning of the room are presented here. The studio's impulse responses are measured according to the ABNT NBR ISO 3382-2:2017 standard, and the main acoustic quality parameters, such as T30, EDT, C80, D50 and STI, are calculated. The T30 values varied between 0.5 s at 125 Hz and 0.75 s at 630 Hz. The values obtained are far from what is adequate for a studio, requiring an acoustic conditioning project. Undesirable effects of the room's modal behavior were also observed. Then a modal analysis is performed using the finite element method in open-source software. The simulation indicated the main resonance frequencies as 50, 63, 77 and 130 Hz, as well as the points in the room where resonance peaks occur. This information indicates where the application points for low-frequency absorbers should be concentrated in the acoustic conditioning of the studio. The results related to sound insulation are the subject of another publication.