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:
Nov. 20, 1990
Filed:
Sep. 21, 1989
Applicant:
Inventors:
Shinichi Oki, Hirakata, JP;
Toshihiko Ohashi, Hirakata, JP;
Fumiyasu Konno, Osaka, JP;
Hiroshi Yagi, Neyagawa, JP;
Takahiro Nakauma, Moriguchi, JP;
Assignee:
Matsushita Electric Industrial Co., Ltd., Kadoma, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H03G / ;
U.S. Cl.
CPC ...
381 97 ; 381 98 ; 381103 ; 381 86 ; 333 / ;
Abstract
A sound reproduction system suitable for automobile, the reproduction system having a band-pass filter, a phase-shifter for shifting the output of the band-pass filter and a mixer which mixes the output of the phase-shifter with the original audio signal at a suitable mixing ratio, whereby a low frequency standing wave which is generally produced in the small automobile room may be eliminated, thereby providing a desirable frequency response characteristic.