Patent ID: 7940953

Claim:
An electro-acoustic transducer, comprising: a membrane that comprises a sheet of film material, the membrane having two upper ends that extend from a lower end separated by an angle less than ninety degrees, an inner surface, and an outer surface; a frame that supports the membrane in at least the upper ends of the membrane; a voice coil comprising a structured conductive layer arranged on at least one of the inner or outer surfaces of the membrane, that moves the membrane dependent on an electrical input signal; at least one ferromagnetic element arranged in the membrane or on one of the inner or outer surfaces of the membrane at the lower end of the membrane; a first magnet attached to the frame in a position adjacent to the lower end of the membrane; and a second magnet attached to the frame adjacent to a first of the two upper ends of the membrane, and a third magnet attached to the frame adjacent to a second of the two upper ends of the membrane; where the at least one ferromagnetic element is pulled down by a magnetic force between the at least one ferromagnetic element and the first magnet establishing a gap between the first magnet and the at least one ferromagnetic element such that tensioning of the membrane is effected by the magnetic force.