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Effects of Different Building Materials and Treatments on Sound Field Characteristics of the Concert Hall

The effects of different building materials on sound field characteristics of the concert hall were studied by experimental study and numerical simulations. A single non-directivity excitation sound source in situ test was carried out. The acoustic analysis model of the multifunctional concert hall was established. The reverberation time, the early decay time, the speech transmission index and the sound pressure level (SPL) were tested. The architectural treatment solutions with or without sound absorption in the design ceiling, sound absorption on the side walls, the influence of ceiling form on acoustic characteristics, and the acoustic characteristics of different positions on the first and second floors were analyzed, respectively. Simulation results show that there was little difference in reverberation time at different reception points by using the same treatment solutions, and the speech transmission index increased with the distance of the reception point. The language performance of the positions on the second was better than on the first floor. The SPL decreased with increasing distance from the receiving point. The ceiling form had no significant effects on the acoustic characteristics of the multifunctional concert hall, and the reverberation time was smaller when acoustic materials were used in the ceiling than the side walls. Meanwhile, the language transmission performance in multifunctional concert halls was improved. The difference between the maximum and minimum sound pressure levels for a sound-absorbing material ceiling is less than that of a non-sound-absorbing material.