Tabletop demonstration of multiple source interference using ultrasonic transducers

Abstract

Superposition of multiple sources, constructive and destructive interference, and array beam forming are common topics demonstrated in undergraduate acoustic classes. The student learning experience is enhanced by building a system with speakers and measuring the resulting amplitude at various angles with a microphone. This experiment is often performed in an anechoic chamber to achieve quantitative agreement between theory and experiment. We have developed a simple tabletop apparatus using inexpensive ultrasonic transducers that yields comparable results without the need to use an anechoic chamber.