Timbre of Kiais: Analysis and synthesis

Abstract

Kiai is a name given to sudden and violent vocalizations practised by Martial Artists. An investigation to determine formant frequencies, bandwidths and source‐spectrum giope was performed on vocalizations made by five high ranking Karateka. Spectral classifications were made using adaptations of those used for infant cries [H. M. Truby and J. Lind Act, Paed. Scand. 163, 11 (1965)]. All cepstra show strong peaks regularly spaced at pitch‐period intervals. This phenomenon is usually linked with irregularities in the pitch‐pulse timing [A.M. Noll, J. Acoust. Soc. Am. 41, 293–309 (1967)]. However digital simulations using a Terminal Analog Synthesizer indicate that it is likely that these peaks are due to an opening quotient of the vocal cords which is less than 10%. This leads to a nearly flat source spectrum. The fundamental frequency range was found to be in the order of 450–500 Hz and high amplitude resonances were found up to 6000 Hz for all vocalizations studied. Physiological considerations concerning the production and perception of these screams will be discussed and shown to be consistent with claims that Kiais have a characteristic timbre, which this analysis supports. [Work supported by U. M. E. R. G.]