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:
Feb. 03, 1976
Filed:
Jul. 08, 1974
William V Machanian, Lewiston, NY (US);
Robert R Williams, St. Joseph, MI (US);
The Wurlitzer Company, Chicago, IL (US);
Abstract
The embodiment of the invention disclosed herein is directed to an electronic musical instrument of the keyboard type used to electronically reproduce piano sounds. The circuit has means to vary the amplitude of the piano voice in response to the velocity of the downward movement of the key. Means are provided for producing a fundamental square wave frequency and the second and fourth harmonics thereof, in response to the actuation of a given key on the keyboard. One circuit arrangement includes means for combining the fundamental frequency and the second and fourth harmonics in a predetermined time relation to produce the zero, attack, peak, and decay characteristics of a piano voice as actually produced by a piano string. Amplitude limiting means are coupled to the circuit for controlling the amplitude of the harmonics in response to predetermined values so that mixing of the fundamental frequency and the second and fourth harmonics along predetermined points of the piano voice characteristics curve will more accurately reproduce electronically the sounds of a piano. Another circuit arrangement provides means for rapid recovery of the piano circuit so that the keys can be actuated in rapid succession.