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. 10, 2000
Filed:
Sep. 25, 1997
Masamitsu Hirano, Shizuoka-ken, JP;
Noro Masao, Shizuoka-ken, JP;
Yamaha Corporation, Hamamatsu, JP;
Abstract
A sound field expanding apparatus is formed from an L-channel sound field expanding circuit and an R-channel sound field expanding circuit that have substantially the same circuit structure. Left and right stereophonic input signals of two channels are input in the L-channel sound field expanding circuit and the R-channel sound field expanding circuit, respectively. The L-channel sound field expanding circuit and the R-channel sound field expanding circuit include a first amplitude/phase characteristic changing circuit and a second amplitude/phase characteristic changing circuit, respectively. The first amplitude/phase characteristic changing circuit and the second amplitude/phase characteristic changing circuit add specified amplitude/phase characteristics to the respective input signals to generate a specified sound field expanding effect. The first and second amplitude/phase characteristic changing circuits are formed on a single IC chip with switched capacitor filters, and have the same structure for both of the first and second amplitude/phase characteristic changing circuits.