sensitivity to voltage

6.56  sensitivity to voltage; transmitting voltage response. Of an electroacoustic transducer for sound emission, for a specified frequency, quotient of the sound pressure in a free field at a specified distance from the effective acoustic center, and in a specified direction, by the signal voltage applied at the input terminals. Unit, pascal per volt (Pa/V).

Annotation              When the effective acoustic center of the transducer cannot be easily determined, the distance should be measured from the reference point of the transducer.