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:
Sep. 19, 1978
Filed:
Aug. 13, 1976
Applicant:
Inventor:
Keiichiro Ogura, Kawasaki, JP;
Assignee:
Nippon Columbia Kabushikikaisha, Tokyo, JP;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
H04R / ;
U.S. Cl.
CPC ...
1791 / ; 1791 / ; 179 / ;
Abstract
A discrete 4-channel stereo recording and reproducing system which is based on a regular matrix type 4-channel stereo system and compatible with both of a regular matrix system and a CD-4 type 4-channel stereo system. In the audio frequency band, the same encoding as that in the regular matrix system is performed and, in the carrier frequency band, encoding for satisfying the compatibility with existing systems is achieved. The decoding is intended to improve the sound image location and separation in the reproduced sound field from CD-4 type stereo signals and automatic switching of a decoding circuit for the regular matrix type signals is achieved.