Melville Clark, Jr.
Inst. for Sci. Res. in Music, 8 Richard Rd., Wayland, MA 01778-4099
Results of the analysis, synthesis, and perturbation of the sounds of traditional acoustic musical instruments obtained between approximately 1955 and 1972 by several methods will be summarized. The behavior of the sounds produced by various acoustic instruments and the features found to be important and unimportant to the sounds of several percussive and nonpercussive instruments will be reported and a demonstration provided. For example, it has been found important for nonpercussives to provide an attack transient and pseudosteady state, while the decay transient is of much less importance in normally reverberant environments. For percussives, the first part of the sound is of very little auditory significance, but the decay transient is of overwhelming importance. The changes of partials with time during the important epochs is perceptually significant. To prevent tones from cloying, addition of or modulation with pink noise in just the right way and in the right amount is greatly desired. In other situations, inharmonicity of certain partials is vital to the quality of sound. The view is taken that if most people can NOT hear something, that something is NOT important; if most people can hear that something, it is important.