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:
Feb. 25, 1986
Filed:
Oct. 19, 1983
Applicant:
Inventor:
David S Hall, Palo Alto, CA (US);
Assignee:
Velodyne Acoustics, Inc., Santa Clara, CA (US);
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
H04R / ;
U.S. Cl.
CPC ...
381 96 ; 381 59 ; 1791 / ;
Abstract
A moving-coil loudspeaker system incorporating motional feedback operable at high frequencies, i.e. above about 1000 Hz. The feedback signal is developed by a tiny piezo-electric accelerometer mounted together with a charge amplifier directly on the loudspeaker coil, in alignment with the turns of the coil. The coil comprises two layers of rectangular, anodized aluminum wire wound tightly to form an effectively integral mass. The system includes a suitable stabilizing frequency compensation network.