US PATENT SUBCLASS 381 / 74
HEADPHONE CIRCUITS

Current as of: June, 1999
Click HD for Main Headings
Click for All Classes

Internet Version by PATENTEC © 1999      Terms of Use


381 /   HD   ELECTRICAL AUDIO SIGNAL PROCESSING SYSTEMS AND DEVICES

74HEADPHONE CIRCUITS

DEFINITION

Classification: 381/74

HEADPHONE CIRCUITS:

(under the class definition) Subject matter having means to perform a desired electrical or electronic function in conjunction with a device held against the ear having a diaphragm which vibrates according to current variations.

SEE OR SEARCH THIS CLASS, SUBCLASS:

68, for electrical hearing aids.