Statistical study of spectral parameters in musical instrument tones

Methods for short-time spectral analysis [improved over J. Acoust. Soc. Jpn. 33, 233–241 (1977)] and for extracting time-varying amplitude levels and frequencies of partials from musical instrument tones are described. The accuracy of the combined method is examined by applying the method to a synthetic tone having 32 harmonics. Statistical presentations used include histograms and graphs of average sound pressure level spectra, arithmetic mean sound pressure levels, and standard deviations of frequencies and amplitude levels, as well as autocorrelation and cross-correlation functions for various parameters. Seven tones produced by a violin, a flute, an oboe (with and without vibrato), and by a trumpet (nonvibrato) were analyzed. Characteristic features of the time-varying spectral parameters of each musical instrument tone were obtained. Applications of the results to the synthesis of musical instrument tones are considered. As a result, it is suggested that it will be possible to synthesize good synthetic musical instrument tones by realizing the statistical nature of the extracted spectral parameters.