James K Demeter

US Patent:

40103340, Mar 1, 1977

Filed:

Jan 27, 1975

Appl. No.:

5/544407

Inventors:

James K. Demeter - Canoga Park CA

International Classification:

H04R 146
H04R 1004

US Classification:

179114M

Abstract:

A dynamic acoustic transducer device of small, compact, highly efficient design, wherein a vibratable diaphragm is supported in an open side of a casing, a pair of permanent magnets being secured to the diaphragm for vibrational movement therewith, the magnets extending into the casing and being respectively surrounded by an electric coil winding which is isolated against vibrations of the diaphragm, the coils being connectable with a signal circuit. When the dynamic transducer comprises a microphone, the device is susceptible of mounting in an operating position by adhesively securing the outer surface of the diaphragm to a vibratable surface of a musical instrument, or other vibratable medium so that the relative movements between the magnets and coils in response to the sensed vibrations will function to produce a modulated output signal capable of being amplified and coupled to a loudspeaker. When the transducer is embodied in a device for the generation of sound waves, for example, in a loudspeaker system, a modulated electric signal is utilized to energize the coils and by interaction with the magnets to drive the diaphragm.