Abstract: A touch sensitive system for an electronic musical instrument providing a multiple key switch contact system for effecting control over two or more tone generating systems. The first tone generating system operating rapidly in response to the actuation of the key switch to produce a desired voice. The second or subsequent tone generating systems operate sequentially in a delayed manner on the actuation of the key switch effecting a predetermined delay in the production of the desired voice. The audio output of each of the tone generating systems is summed forming a resultant waveform for audio amplification. The key switch actuation, depression and release, causes the tone generating systems to respond immediately to the depression or release of the key switch which effects a change in the envelope characteristics of the resultant waveform.

Abstract: The string snub effect functions so as to introduce a different set of parameters for the harmonic content, envelope amplitude, shape and rate of decay and pitch of the resulting sound upon key release when a percussive string-type voice is selected in an electronic musical instrument. The apparatus for causing a snubbing of the resulting tone comprises a means for selecting a percussive string-type waveform and for generating a signal indicative of such selection, a means for detecting the release of a depressed key and the presence of the signal indicative of the selection of a percussive string-type waveform and for generating a signal indicative of such detection, a means for halting further interpolation of the selected waveform and switching to a preselected harmonic structure of said selected waveform, means for shifting the pitch of the generated tone of said selected waveform, and means for variably controlling the envelope amplitude, shape and rate of decay of the selected waveform.

Abstract: An electronic musical instrument is provided with a keyboard which may comprise one or more keyboard sections. Plural instrument voices are stored in memory for each section of the instrument keyboard. Each stored voice comprises a set of plural multiple bit digital words. A composite audible tone corresponding to an active key comprises varying combinations of component signals derived from the stored voices. The decay pattern of the composite audible tone is divided into successive time zones. The durations of the zones may vary. For each zone, the amplitude of at least one of the component signals of the composite tone is caused to decay while the amplitudes of the remaining component signals are either not modulated or are maintained at zero. The rate of decay of the amplitude of a component signal, hence the duration of a particular time zone, may be made a function of the keyboard section associated with the active key. In an alternative embodiment, the instrument voices are not stored in memory.

Abstract: The present invention is a two-part apparatus for producing note attack and decay in a conventional electronic musical instrument. Either part of the invention may be used independently of the other; however, at present the combined use is preferred. In part one, there is provided an eight state counter clocked at a rate equal to the note generator cycle and a digital magnitude comparator. The inputs (A) from the eight state counter are compared to the attack and decay scale factor inputs (B) by the comparator. The A>B,A=B functions are generated by the comparator in combination with an OR gate. The OR gate output and the sample gating signal from the conventional musical instrument are applied to an AND gate which outputs a modulated sample gating signal. In part two, the modulated sample gating signal of part one is subpulsed individually by two subpulses.

Abstract: A method and apparatus for interpolating between the harmonic structures of a waveform stored in memory during the transient periods of said waveform. In an electronic musical instrument having a greater number of selectively actuable switches than generators to cause the production of sound corresponding to the respective notes of the musical scale the present invention interpolates between the harmonic structures of a waveform stored in memory during the transient period of that waveform. This is accomplished through the use of memory units having a number of locations or zones within each memory where the number of zones is equivalent to the number of discrete harmonic structures. The first of the memory units contains a discrete fixed harmonic structure in each of its zones, and a second of the memory units contains a difference value in each of its zones where the difference value is equal to the difference between the discrete fixed harmonic structure in adjacent zones of the first memory.

Abstract: A method and apparatus for reproducing the complete attack transient and steady state portions of a waveform is disclosed.

Abstract: A method and apparatus for interpolating between the harmonic structures of a waveform stored in memory during portions or the entire transient periods of said waveform. In an electronic musical instrument having a greater number of selectively actuable switches than note generators to cause the production of sounds corresponding to the respective notes of a musical scale, the present invention interpolates between the harmonic structures of a waveform stored in memory during portions or the entire transient periods of said waveform. This is accomplished through the use of memory units having a number of locations or zones within each memory where the number of zones is equivalent to the number of discrete harmonic structures.

Abstract: A digital musical instrument incorporating the effects of attack and decay by appropriately scaling the digitally synthesized waveform information at the leading and trailing portions of the waveform envelope. Such an instrument would be capable of producing two attack and decay periods with only one attack and one decay period resulting in the normal audible effect. The system is particularly adapted for use in an electronic musical instrument in which a digital multiplexed signal is generated by actuation of the keys of the instrument. The attack and decay periods generated by actuation and deactuation of the keys are processed such that each period is divided into "n" scale factors spaced in time, each such scale factor being associated with a different level of the waveform envelope. The scale factors cover the range of waveform envelope from zero to full scale. Upon receipt of a clear pulse, the digital counter begins counting, and would terminate the count upon reaching "n".