EVALUATION OF OPTIMAL ACOUSTIC PARAMETERS FOR JAVANESE GAMELAN CONCERT HALL USING PSYCHOACOUSTIC TEST

• Main Author: Sarah Hanitio, Quinn
• Format: Final Project
• Language: Indonesia
• Subjects: Teknik (Rekayasa, enjinering dan kegiatan berkaitan)
• Online Access: https://digilib.itb.ac.id/gdl/view/47962
• Institution: Institut Teknologi Bandung

Several studies on optimal acoustic parameters for the Javanese gamelan along with concert hall designs for Javanese gamelan has been conducted using the fan-shaped (one of the three basic concert hall shapes) as its base, therefore, further research on optimal acoustic parameters for shoebox and vineyard shapes is necessary. This research was conducted through psychoacoustic testing, where models of the three basic concert hall shapes as well as three reverberation time variations for each shape were created beforehand. Then, auralizations of a Javanese gamelan dry recording were conducted in all simulated model variations. The recordings of differing reverberation times were played and tested on 35 research participants using the pairwise comparison method to obtain the acoustic parameter preferences for fan-shaped, shoebox, and vineyard concert hall shapes. Moreover, an interview with a gamelan expert was carried out and an impulse response analysis was conducted in order to obtain RT60, IACC, LL, ITDG, and C80 values of the variation with optimal acoustic parameters. The psychoacoustic test results showed that the concert hall’s shape difference does not affect the optimal acoustic parameter preferences. The simulations result in the following values: RT60 values range between 1.34-1.39 s, LL values range between 73.4-74.7 dB, ITDG values range between 34.4-36.6 ms, IACC values range between 0.53-0.56, and C80 values range between 1.49-2.17 dB. Based on interview and listening test with a gamelan expert, an descending order of preference of fan-shaped, shoebox, and vineyard concert hall shapes was established where the expert stated that the preferred hall shape has a smaller “echo”. Further analysis on LL, ITDG, and C80 acoustic parameters was done in order to find out which parameters affect the subjective preference, and it was found that the order of preference is influenced by LL at the 125 Hz frequency as well as ITDG at the 500 Hz frequency. Correlation analysis gives a conclusion that the “echo” referred to is related with the ITDG value since the RT60 for all three concert hall are constant.