reciprocity principle

6.59  reciprocity principle. For an electroacoustic transducer that is linear, passive, and reversible, principle according to which: (a) the relation between the voltage sensitivity (transmitting voltage response) of the transducer functioning as a receiver of sound (e.g., a microphone), and the sensitivity to current (transmitting current response) of the transducer functioning as an emitter of sound, and, (b) the relation between the current sensitivity of the transducer functioning as a receiver of sound (e.g., a microphone) and the sensitivity to voltage (transmitting voltage response) of the transducer functioning as an emitter of sound, depend only on the geometry of the transducer, the frequency, and the physical properties of the medium.

Annotation              The Reciprocity Principle also refers to the transfer function between a source and receiver being the same when the positions of source and receiver are interchanged.