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:
Dec. 17, 1985
Filed:
Mar. 08, 1984
Zenju Otsuki, Kawasaki, JP;
Mamoru Inami, Yokohama, JP;
Thomson-Brandt, Paris, FR;
Abstract
In a circuit arrangement for automatically correcting frequency response so as to set a desired frequency response in view of a frequency response of a sound field, a frequency response control circuit is improved such that precise level control at a number of bands is effected with a simple structure. A microcomputer is used to determine the difference between a desired frequency response curve and a frequency response curve obtained by measuring the sound pressure level in a sound field, to which pink noise or the like is emitted through the frequency response control circuit, so as to produce a control signal used in the frequency response control circuit to give a desired frequency response to an audio signal. The frequency response control circuit comprises an amplifier, a plurality of resonance circuits corresponding to the bands, a plurality of variable resistor circuits each including a parallel circuit of a plurality of series circuits of a resistor and an analog switch; and an interface circuit responsive to serial data of the control signal from the microcomputer for controlling the analog switches.