Abstract: A loudspeaker capable of improving the efficiency, providing a high performance, and reducing its weight. In a general loudspeaker or a loudspeaker having a repulsion magnetic field type magnetic circuit, the whole or part of the voice coil 1 uses a composite wire A formed by a conductive wire made of conductive material C and a magnetic material F provided at least partially on the surface of the conductive wire, or a composite wire A formed by a magnetic wire made of magnetic material F and a conductive material C provided at least partially on the surface of the magnetic wire.

Abstract: A nondirectional acoustic generator includes two acoustic generator units which are disposed facing each other as near as possible to the extent that diaphragms thereof do not become in contact with each other, drive units of the acoustic generator units being connected in series or in parallel to drive the acoustic generator units in phase and generate air compression sound waves which are radiated in the circumferential direction of the diaphragms.A speaker system includes a plurality of nondirectional acoustic generators coaxially disposed so as to align the centers of respective diaphragms and make the phases at sound generating areas coincident with each other.

Abstract: A wiring structure of a loudspeaker having a signal input path to a voice coil, the path being established by electrically interconnecting a conductor and an input terminal mounted on a frame, and the conductor being disposed, on a damper having corrugations of concentric circles, along the corrugations from the inner to outer periphery thereof, includes a projection mounted on the damper extending from the outer periphery of the damper to a substrate of the input terminal, the end of the conductor being extended on and along the projection, whereby the end portion of the conductor is connected to a lug on the substrate of the input terminal.

Abstract: A speaker diaphragm is formed by heat-pressurized molding a composite structure of fabric cloth and resin sank into the fabric cloth. The fabric cloth is woven from high strength and high elasticity polyethylene fiber which has at least tensile modulus of 4,500 kg/mm.sup.2 (500 g/d).

Abstract: A method of forming diamond-like carbon layer which is advantageously adaptable as a coating layer on acoustic diaphragms. In the method, carbon vaporized out of solid carbon source is deposited onto the surface of the diaphragm as the coating layer in the atomosphere of catalystic gas, for instance, H.sub.2 +Ar or H.sub.2 of about 10.sup.-4 Torr. The deposited carbon layer on the surface of the diaphragm is an amorphous carbon of inclusion of hybridized orbital SP.sup.2 bond and hybridized orbital SP.sup.3 bond and crystalline carbon particles of hybridized orbital SP.sup.3 bond dispersed in the amorphous carbon, or an amorphous carbon of inclusion of hybridized orbital SP.sup.2 bond and hybridized orbital SP.sup.3 bond.

Abstract: In an electroacoustic converter, center pole and top plate which constitute a magnetic circuit are mechanically abutted against each other by interposing an air gap defining member therebetween. The air gap defining member is a projection provided on the center pole or top plate, otherwise non-magnetic ring-like sleeve covered on the center pole or top plate. An air gap in the magnetic circuit can be precisely defined by the air gap defining member without using any alignment tool in its assemble process.

Abstract: A method of forming diamond-like carbon layer which is advantageously adaptable as a coating layer on acoustic diaphragms. In the method, carbon vaporized out of solid carbon source is deposited onto the surface of the diaphragm as the coating layer in the atmosphere of catalystic gas, for instance, H.sub.2 +Ar or H.sub.2 of about 10.sup.-4 Torr. The deposited carbon layer on the surface of the diaphragm is an amorphous carbon of inclusion of hybridized orbital SP.sup.2 bond and hybridized orbital SP.sup.3 bond and crystalline carbon particles of hybridized orbital SP.sup.3 bond dispersed in the amorphous carbon, or an amorphous carbon of inclusion of hybridized orbital SP.sup.2 bond and hybridized orbital SP.sup.3 bond.

Abstract: A speaker system comprising a speaker cabinet having a forward baffle plate, two side plates and a rear plate, a passive diaphragm, a speaker mounted in the baffle plate of the speaker cabinet, an opening disposed in the baffle plate next to the speaker as an outlet for the sound radiated from the passive diaphragm, a dividing plate slantedly disposed between the baffle plate and the rear plate of the speaker cabinet, the dividing plate dividing the speaker cabinet into a first part including the speaker and a second part including the opening, the passive diaphragm being mounted in the dividing plate.