The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 27, 1987
Filed:
Apr. 17, 1986
Ralph Deutsch, Sherman Oaks, CA (US);
Kawai Musical Instruments Mfg. Co, Ltd, Hamamatsu, JP;
Abstract
A keyboard operated musical instrument is disclosed in which musical tones are created by reading out data values stored in a waveshape memory. The number of stored data points is reduced by storing the data values in segments corresponding to one-half of the number of data points for a period of a waveshape. By using synthesized data having a symmetry about the midpoint, the second half of the waveshape is recovered by a forward and backward memory address read of each waveshape segment. After reading each segment a predetermined number of cycles, an abrupt jump is made to the next segment of waveshape data points. The fundamental frequency of the tone is varied in a temporal manner by changing the memory advance rate of reading waveshape data out of memory in response to a frequency offset data corresponding to each segment of the waveshape data. An alternative embodiment is disclosed for a tone generator in which the musical waveshape is computed in real time from stored sets of harmonic coefficients.