Application of in-situ method for measuring sound absorption coefficient of direct piercing carved wood panel with daun sireh motif

Abstract

An application of In-Situ method of measuring sound absorption coefficient on the surface of direct piercing carved wood panel using the concept of "ensemble averaged" is discussed. The method offer an easier way to measure the absorption performance α for each individual aperture of carved wood panel with floral pattern which was replicated from one of the oldest mosque, namely Masjid Abidin located in Terengganu, Malaysia. Two pieces of 20 mm thick of cengal wood (Neobalanocarpus heimii) with 30% and 40% perforation ratio were respectively measured in a reverberation room in order to determine the value of α. At lower frequencies (0.1 kHz-1.5 kHz), the measured values of α for both direct piercing carved wood panel with floral pattern (Daun Sireh motif) are shown that the sound absoption for both direct piercing carved wood panel are in perform level. From the measurements, clearly, the installation of the direct piercing carved wood panel with floral pattern (Daun Sireh motif) in the Masjid Abidin can provide better air circulation and additional natural sunlight, as well as better sound intelligibility inside the building.