Question

Can anyone provide a good exposition on acoustic impedance?

Answer 1

in very basic terms, it is a measure of the "resistance" an acoustic wave (propagation) will encounter. Since an analogy with electric impendance is used, this analogy can be taken further and find the analog of acoustic pressure and volume and see this better. You should keep in mind that, like electric impendance, acoustic impendance is just an auxiliary concept used in various equations. One can very well use another measure or concept for the same purpose.

Answer 2

A megaphone can be modeled as an impedancetransformer that has one characteristicimpedance at its entry port and another at its exit.