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. 19, 1978
Filed:
Jun. 29, 1977
Applicant:
Inventors:
James M Kates, Norfolk, MA (US);
Robert A Berkovitz, Lexington, MA (US);
Assignee:
Teledyne, Inc., Los Angeles, CA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H04R / ;
U.S. Cl.
CPC ...
179 / ;
Abstract
Variations in the amplitude-frequency response characteristic of a loudspeaker are compensated by a drive circuit in which an audio input signal is summed with a plurality of delayed replicas of the input signal to provide a drive signal for the loudspeaker. The delayed replicas are derived by discrete time filtering. Noise reduction techniques applied to the least delayed of the plurality of delay signals substantially improves the S/N ratio in the drive signal.