Analog Measurements of Sound Radiation from the Mouth

Abstract

Free-field measurements of the sound radiated from the mouth of a life-size manikin are described. A transducer installed in the head of the dummy is calibrated to produce a known acoustic volume velocity through the lips. The sound field in vertical and horizontal planes through the head is explored with a pressure microphone. Directivity patterns are determined for frequencies of 250, 500, 1000, 2000, and 4000 cps. Radiation of sound from the mouth is compared with that from a small piston set in a rigid sphere of 9-cm radius.