Method and apparatus for dynamic reproduction of transient and steady state voices in an electronic musical instrument

摘要

A method and apparatus for reproducing the complete attack transient and steady state portions of a waveform is disclosed. In an electronic musical instrument providing a means for detecting the depression and release of a key switch, a means for storing a complete attack transient of the waveform and a predetermined number of full cycles of the steady state of the waveform, a means for generating addresses for selectively causing the reading from the storage means the complete attack transient of the waveform and the predetermined number of full cycles of the steady state of the waveform and for generating addresses for selectively causing the repeated reading from the storage means, either randomly or in a predetermined pattern, a number of cycles of the steady state of the waveform until release of the depressed key switch, and means for generating addresses for selectively causing the continued repeated reading from a storage means, either randomly or in a predetermined pattern, a number of cycles of the steady state of the waveform during the decay transient of the waveform until audio ceases. The waveform contains envelope characteristics and is of an harmonically and non-harmonically varying content changing with time. Upon the detection of the completion of the reading of the complete waveform the continued depression of the key switch a number of cycles of the steady state of the waveform are continued to be read from the storage means, either randomly or in a predetermined pattern, until release of the depressed key switch. The repeated reading of the number of cycles is a recirculation of the steady state portion of the waveform and is controlled by a switch means which limits the generated address to a predetermined address or the randomly generated addresses to a predetermined range. The amount of recirculation of the steady state portion of the waveform may also be controlled by incorporating the voice memory data of the first address location of the first cycle of the attack transient portion of the waveform a digital coding limiting the randomly generated addresses to a predetermined range.