Average Speech Directivity
Voice and Speech Directivity
The directivity function of human speech describes the angular dependence of acoustic radiation from and diffraction about a talker and a talker’s chair (if seated). It is an essential physical aspect of communication that affects sounds and signals in acoustical environments, audio, and telecommunication systems. Because high-resolution, spherically comprehensive measurements of live, phonetically balanced speech have been unavailable in the past, the authors have undertaken research to produce and share such data for simulations of acoustical environments, optimizations of microphone placements, speech studies, and other applications. The presented data were acquired from and averaged across three male and three female talkers who repeated phonetically balanced passages in an anechoic chamber. Each was seated on a chair connected to a subject-rotation system, with his or her mouth at the circular center of a 1.22 m-radius, semi-circular array of 37 microphones having Δ𝜃 = 5° polar-angle increments. The mouth axis was aligned toward 𝜃 = 90° in the polar angle (0° elevation) and ϕ = 0° in the azimuthal angle. Azimuthal rotations progressed in Δϕ = 5° increments, meaning data were acquired at 2,522 unique positions over the measurement sphere. They were likewise acquired at three positions within the rotating reference frame for subsequent signal processing. Several steps mitigated the effects of repeated speech variations. The directivities derived from transfer functions and other measurement calculations. The results are available under Additional Files, which may be updated periodically.
Bellows, Samuel D.; Pincock, Claire M.; Whiting, Jennifer K.; and Leishman, Timothy W., "Average Speech Directivity" (2019). Directivity. 1.