Abstract: A dual-coil, dual magnetic gap electromagnetic transducer is provided where each voice coil is wired to include separate leads so that each individual voice coil may be driven by a separate amplifier or by a separate bridged amplifier. Signal processing may further be utilized to increase the output of the loudspeaker, to achieve extreme excursion without extreme distortion and to provide for alternative voice coil designs to address common problems with dual-coil, dual magnetic gap transducers, including, but not limited to, heat generation.

Abstract: An electromagnetic drive motor assembly (EDMA) has at least one bridge that extends along a radial direction to conduct heat away from the magnetic gap and towards the outer surface of the EDMA. The EDMA includes a conductive ring between a first plate and a second plate. The conductive ring has an inner ring, an outer ring, and at least one bridge between the inner and outer rings. The inner ring is adapted to receive a voice coil such that the heat generated by the voice coil conducts through the inner ring, the bridge, and then to the outer ring. As such, a heat conducting path is provided within the EDMA to remove the heat away from the voice coil. This allows the EDMA to operate more efficiently. The EDMA may also include a flux return having a pole piece that protrudes from the first plate. The inner ring of the conducting ring may receive the pole piece to form an intermediate gap between the pole piece and the inner ring.

Abstract: The present invention provides an electromagnetic drive motor assembly (EDMA) that has an inner flux return assembly formed from an upper pole piece and a lower pole piece oppositely disposed relative to each other along the center of the EDMA. An annularly positioned conductive ring (or flux stabilization ring) encircles the inner flux return assembly, concentrically in contact with the outside of the inner flux return assembly. Along the exterior side of the flux return pieces, is a magnet that is between a top plate and a bottom plate. Each plate contacts with the magnet to form a magnetically conductive system. A magnetic gap is formed in between the inner flux return assembly and the top and bottom plates. Disposed within the magnetic gap is a dual coil wound around a cylinder. The dual coil includes a first coil portion and a second coil portion. To minimize the modulation, the top and bottom plates may be saturated and plate tips may be provided near the magnetic gap.

Abstract: An electromagnetic drive motor assembly (EDMA) has at least one bridge that extends along a radial direction to conduct heat away from the magnetic gap and towards the outer surface of the EDMA. The EDMA includes a conductive ring between a first plate and a second plate. The conductive ring has an inner ring, an outer ring, and at least one bridge between the inner and outer rings. The inner ring is adapted to receive a voice coil such that the heat generated by the voice coil conducts through the inner ring, the bridge, and then to the outer ring. As such, a heat conducting path is provided within the EDMA to remove the heat away from the voice coil. This allows the EDMA to operate more efficiently. The EDMA may also include a flux return having a pole piece that protrudes from the first plate. The inner ring of the conducting ring may receive the pole piece to form an intermediate gap between the pole piece and the inner ring.

Abstract: The present invention provides an electromagnetic drive motor assembly (EDMA) that has an inner flux return assembly formed from an upper pole piece and a lower pole piece oppositely disposed relative to each other along the center of the EDMA. An annularly positioned conductive ring (or flux stabilization ring) encircles the inner flux return assembly, concentrically in contact with the outside of the inner flux return assembly. Along the exterior side of the flux return pieces, is a magnet that is between a top plate and a bottom plate. Each plate contacts with the magnet to form a magnetically conductive system. A magnetic gap is formed in between the inner flux return assembly and the top and bottom plates. Disposed within the magnetic gap is a dual coil wound around a cylinder. The dual coil includes a first coil portion and a second coil portion. To minimize the modulation, the top and bottom plates may be saturated and plate tips may be provided near the magnetic gap.

Abstract: The present invention provides an electromagnetic drive motor assembly (EDMA) that has an inner flux return assembly formed from an upper pole piece and a lower pole piece oppositely disposed relative to each other along the center of the EDMA. An annularly positioned conductive ring (or flux stabilization ring) encircles the inner flux return assembly, concentrically in contact with the outside of the inner flux return assembly. Along the exterior side of the flux return pieces, is a magnet that is between a top plate and a bottom plate. Each plate contacts with the magnet to form a magnetically conductive system. A magnetic gap is formed in between the inner flux return assembly and the top and bottom plates. Disposed within the magnetic gap is a dual coil wound around a cylinder. The dual coil includes a first coil portion and a second coil portion. To minimize the modulation, the top and bottom plates may be saturated and plate tips may be provided near the magnetic gap.

Abstract: A compact speaker is enabled to mount into panels made with either of two different sized standard mounting cutout patterns, e.g. Japanese JIS or the larger European DIN, providing the small JIS overall basket diameter along with an unusually large effective cone “air piston” diameter with full excursion for enhanced low frequency response. For mounting to a JIS-configured panel, an annular adaptor ring is configured with an array of four mounting screw clearance holes in a JIS pattern by which the ring is attached to the panel, and four threaded holes on a larger circle by which the basket is then attached to the ring by relatively small sized machine screws. For mounting to a DIN-configured panel, the adaptor ring is not used: the plastic basket is configured with four extending ears providing clearance mounting holes at DIN mounting locations for self-tapping screws by which the speaker is mounted to the DIN-type panel.