Development a Cost-Effective Impedance Tube for Sound Transmission Loss Measurement

Abstract

An impedance tube is an equipment used for normal incidence sound absorption and transmission loss measurement. Unfortunately, this equipment is considered equally expensive. Therefore, this study presents an effort to develop a cost-effective impedance tube for sound transmission loss (STL) measurement. The development of impedance tube consists of speaker, speaker box, acrylic tube, mechanical coupling, BSWA microphone and, Data Acquisition Unit (DAQ). The design and development of impedance tube along with set up and procedure according to ASTM E2611. In this study, the developed impedance tube is used to measure and analyse the STL for different types of sample material, such as foam, Perspex, and other building element materials. Next, data obtained from the developed impedance tube was compared with a standard commercial tube made by Brüel& Kjær for the validation. According to the data comparison, it turns out that both results are encouraging and in similar trend. In conclusion, a goal to develop an impedance tube for STL measurement was achieved but few methods need to be adjusted in future for a better outcome.KeywordsImpedance tubeSound Transmission Loss (STL)Cost-effective