Abstract:
Sound absorption properties of kapok composites and kapok fibrous mat have been investigated. Kapok fibrous assemblies with different thickness and matrix binder were manufactured, and their acoustical performances were evaluated by using an impedance tube instrument. This research reports the development of a method for measuring the absorption coefficient of a material specimen mounted at one end of a planar wave tube using a two microphone method. In the proposed method, the two microphone mounted is used as a measuring device to calculate the transfer function of the reflected wave. An actuator (loudspeaker) is used to generate sound waves which driven by the amplifier.