Mechanical/Acoustical Equivalent Circuits
John C. Cochran · 2022
This chapter introduces the concept of a mechanical and acoustical equivalent circuit. The impedance analogy is the best method for solving problems consisting of purely acoustical elements. The concept of mobility represents the analog to impedance. The chapter focuses on this concept. In the impedance analog, the acoustic pressure is the potential function and the volume velocity is the flux variable. The chapter combines both mechanical and acoustical elements. The best way to show how this is done is by example. It is, or will, become evident that virtually every electroacoustic transducer can be described by a two-port network. The boundary conditions of the two-port network are important for they impact the measurements made at the input. The chapter then considers the relationship between the transmit and receive characteristics of a reciprocal transducer at frequencies well below the transducer's resonance frequency.