Frank H. Slaymaker
134 Glen Haven Rd., Rochester, NY 14609
By storing a digital representation of the impulse response of an equivalent filter in memory, a set of musical tones can be generated in which every tone in the set has the same spectral envelope rather than the same wave shape as occurs when the wave shape itself is stored. Similarly, in the tone of a violin played with vibrato the spectral envelope, rather than the wave shape, would be maintained throughout the vibrato cycle. Generating the tones by summing successive read-outs of the stored impulse response requires considerably less memory than that required to store a different wave shape for every note in the range of an instrument. In the absence of a synthesizer which generates tones from a stored impulse response, several examples of brass, woodwind, and string instrument tones have been computed in advance and the tones stored on disk so they can be demonstrated by playing them through a sampler synthesizer.