3.9. Thévenin's theorem
It appears possible, from the foregoing discussions, to represent the operation of a transducer as a combination of electrical, mechanical, and acoustical elements. The connection between the electrical and mechanical circuit takes place through an electromechanical transducer. Similarly, the connection between the mechanical and acoustical circuit takes place through a mechanoacoustic transducer. A Thévenin's theorem may be written for the combined circuits, just as is written for electrical circuits only.