Partial synchrony in musical sounds: Some recent results using time-variant spectral analysis
James W. Beauchamp, Robert C. Maher · The Journal of the Acoustical Society of America · 1988
Time-variant techniques have been used to analyze quasiharmonic musical signals in terms of s(t) = ∑ k 1nck (t)cos(2π∫fk (t)dt + θk). One type of synchronous behavior occurs when each harmonic amplitude obeys a definite monotonic relationship ck = Fk (c1). This appears to be approximately true for nonvibrato reed-instrument tones, with the notable exception of their attack epochs. On the other hand, the functions relating the harmonic amplitudes of flute tones exhibit considerable hysteresis. Another type of synchrony has to do with harmonicity and whether the frequencies of the partials are harmonically locked together so that fk (t) = kf1(t). Partials of vocal tones with ribtaro appear to obey this relationship, but those of oboe tones do not. Examples of the analysis and synthesis of sounds with and without synchronous behavior will be given.