A contribution towards a model for an artificial voice
George F. Kuhn, Chris Saner · The Journal of the Acoustical Society of America · 1980
The acoustic pressure amplitudes radiated from the mouth of a storeroom manikin were measured in a 6 cm × 6 cm vertical plane immediately forward of the lips. The sound was produced by an acoustic driver in the manikin's head. The lips were immoveable, forming an approximately trapezoidal aperture with an area of 6.5 cm2. Pressure measurements were made at the 13-Octave band center frequencies from 1.0 to 6.3 kHz. The measured results at 1.25 kHz agree well with the speech measurements at 1.3 kHz reported by Leman [4th Int. Conf. Acoust., abstr. G36 (1962)]. As pointed out by Leman, the spreading of the acoustic wave, on axis, can be described by an ideal point source displaced 1 cm horizontally from the tip of the lips. Below the lips, near the chin surface, the acoustic pressure does not spread spherically. Also, the farfield azimuthal directivity of speech measured by Moreno and Pfretzschner [Acoust. Lett. 1, 78–84 (1979)] is shown to be predicted reasonably well by a point source on a sphere, except in an approximate ±20° sector centered at the shadowed pole. However, the median plane vertical directivity differs from that of a point source on a sphere due to body diffraction. [This work was done while the authors were with the Electrical Engineering Department, University of Wyoming, Laramie, WY 82071.]