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:
Inventor:
James M Kates, Norfolk, 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 delayed signal derived from the input signal to provide a drive signal for the loudspeaker. The delayed signal is derived by discrete time filtering and may be formed by storing successively sampled values of the input or drive signal in either digital or analog form, and subsequently recalling the stored values in sequence, or by passing the input or drive signal through a series of all-pass phase-shift filters.