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:
May. 29, 1990
Filed:
Nov. 13, 1987
Masaki Kudo, Hamamatsu, JP;
Hideo Suzuki, Hamamatsu, JP;
Yamaha Corporation, Hamamatsu, JP;
Abstract
An envelope shape generator generates envelope shape data for controlling a tone signal in the form of data in decibel representation. In performing a rapid attenuation control called 'forcing damp' during attenuation of the envelope shape data generated by the envelope shape generator, the envelope shape data in decibel representation is rapidly attenuated with such a characteristic that inclination of attenuation becomes increasingly steeper. This is advantageous because inclination of a rapidly attenuating portion is modified to a substantially uniform inclination when the envelope shape data is converted to data in linear representation. There are also provided a detection circuit for detecting that the level of the envelope shape has dropped below a predetermined level corresponding to a minimum level at which a tone waveshape can be effectively represented and a circuit for rapidly attenuating the envelope shape in response to this detection. This contributes to elimination of noise.