Pulse generator for an electronic musical instrument
AssigneeKimball International, Inc.
InventorStephen L. Howell
Life of this patent
Estimating the term…
Abstract
A pulse generator especially for an electronic musical instrument in which a "D" type flip-flop is employed with the logic level at the data input thereof being transferred to the output in conformity with the supply to the clock input of a fixed frequency rectangular wave and the supply to the clear input of a rectangular wave having a frequency which is a whole multiple of the fixed frequency. The output at the output terminal of the flip-flop is a pulse having a duty cycle of predetermined length. The pulses at the output terminal are, of course, repetitive and remain at the same duty cycle without variation. By using a plurality of the flip-flops, each having respective inputs to the clock and clear terminals, a desired range of pitches can be generated.
Claims7
In a method of generating musical tones of predetermined harmonic content which comprises;
- supplying a first train of rectangular pulses at audible frequency and a second train of rectangular pulses at a frequency which is a whole multiple of the frequency of said first pulse train, each said supply having a first voltage state during each pulse thereof and a second voltage state in the interval between successive pulses and each pulse having leading and trailing edges, initiating a signal pulse substantially at one of the leading and trailing edges of a said first pulse when said second supply is in one of said states thereof, terminating each signal pulse at the next following change of state of the respective said second supply, and converting the signal pulses to sound.
In a system for generating rectangular pulses of selected duty cycle which will produce musical tones of a predetermined harmonic content when converted to sound;
- D type flip-flop means having data, clock, clear and output terminal means, said data terminal means adapted to be held at logic 1, means for supplying a train of first rectangular pulses at a first predetermined frequency to said clock terminal means, means for supplying a train of second rectangular pulses at a second predetermined frequency which is a whole multiple of said first frequency to said clear terminal means, means for withdrawing rectangular pulses at said first frequency and having a duty cycle of less than 100 percent from said output terminal means, and transducer means connected to said output terminal means for converting said withdrawn pulses to sound.
Dependencies are inferred from the claim text.