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: This invention provides a two-stage phasing plug located within a compression driver. The two-stage phasing plug housed within the compression driver may be coupled to a horn. The two-stage phasing plug includes first and second phasing plugs. The advantages of having a two-stage phasing plug is that the first and second phasing plugs may be simpler to manufacture, cost less and the overall dimensional tolerances may be tightly controlled. The higher dimensional tolerances may be obtained because the first phasing plug may be made from a unitary work-piece, and therefore, may be tooled and cut in the same machining set up. This allows the unitary work-piece to be machined and cut very accurately when compared to assembling separate components together during the manufacturing process. Since the most dimensionally critical area is the rear side of the first phasing plug, the tolerances of the second phasing plug may not be as critical.

Abstract: Loudspeaker and other transducers of the dual-voice-coil/dual-magnetic-gap type can be improved by the addition of one or more annular shorting rings strategically located in the vicinity of the two magnetic gaps. The shorting rings have no effect on a steady state magnetic field but act in opposition to any change in flux density or any displacement of the flux lines such as those that occur under the loading imposed when the voice coils are driven hard with audio frequency current. The location of the shorting rings determines their effect: location close to a voice coil reduces the voice coil inductance, location entirely within the magnetic flux loop centerline favors reduction of second harmonic distortion and higher order even harmonic distortion, a centered location on the flux loop centerline, i.e.

Abstract: This invention provides a two-stage phasing plug located within a compression driver. The two-stage phasing plug housed within the compression driver may be coupled to a horn. The two-stage phasing plug includes first and second phasing plugs. The advantages of having a two-stage phasing plug is that the first and second phasing plugs may be simpler to manufacture, cost less and the overall dimensional tolerances may be tightly controlled. The higher dimensional tolerances may be obtained because the first phasing plug may be made from a unitary work-piece, and therefore, may be tooled and cut in the same machining set up. This allows the unitary work-piece to be machined and cut very accurately when compared to assembling separate components together during the manufacturing process. Since the most dimensionally critical area is the rear side of the first phasing plug, the tolerances of the second phasing plug may not be as critical.

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 invention provides a continuous layer of polymer that is shaped to act as the suspension, the former, and an attachment to the diaphragm. The coil may be located within the pocket providing insulation to the coil thus preventing electrical short circuiting of the voice coil as the voice coil expands or contracts based on its operating temperature. The invention also provides an inner flange area of a suspension that may act as a spring generating additional acoustic energy from the compression driver. The inner flange area may also be tuned to vibrate at a predetermined high frequency. Thus, in certain applications, where more acoustic energy is desired at high frequency, the inner flange area may be tuned to provide that extra acoustic energy. To further increase the high frequency energy generated by the compression driver, the diaphragm may be coupled to the bottom side of the inner flange area.

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: Loudspeakers and other transducers of the dual-voice-coil/dual-magnetic-gap type can be improved by the addition of one or more annular shorting rings strategically located in the vicinity of the two magnetic gaps. The shorting rings have no effect on a steady state magnetic field but act in opposition to any change in flux density or any displacement of the flux lines such as those that occur under the loading imposed when the voice coils are driven hard with audio frequency current. The location of the shorting rings determines their effect: location close to a voice coil reduces the voice coil inductance, location entirely within the magnetic flux loop centerline favors reduction of second harmonic and higher order even harmonic distortion, a centered location on the flux loop centerline, i.e.

Abstract: Loudspeaker and other transducers of the dual-voice-coil/dual-magnetic-gap type can be improved by the addition of one or more annular shorting rings strategically located in the vicinity of the two magnetic gaps. The shorting rings have no effect on a steady state magnetic field but act in opposition to any change in flux density or any displacement of the flux lines such as those that occur under the loading imposed when the voice coils are driven hard with audio frequency current. The location of the shorting rings determines their effect: location close to a voice coil reduces the voice coil inductance, location entirely within the magnetic flux loop centerline favors reduction of second harmonic distortion and higher order even harmonic distortion, a centered location on the flux loop centerline, i.e.

Abstract: This invention provides a compensation system capable of compensating for power loss due to the power compression effects of the voice coil as the temperature of the voice coil increases. To compensate for the power compression effect, the invention predicts or estimates the temperature of the voice coil using a thermal-model, and adjusts the estimated temperature according to the cooling effect as the voice coil moves back and forth in the air gap. The thermal-model may be an equivalent electrical circuit that models the thermal circuit of a loudspeaker. With the input signal equating to the voltage delivered to the loudspeaker, the thermal-model estimates a temperature of the voice coil. The estimated temperature is then used to modify equalization parameters.

Abstract: The invention provides a continuous layer of polymer that is shaped to act as the suspension, the former, and an attachment to the diaphragm. The coil may be located within the pocket providing insulation to the coil thus preventing electrical short circuiting of the voice coil as the voice coil expands or contracts based on its operating temperature. The invention also provides an inner flange area of a suspension that may act as a spring generating additional acoustic energy from the compression driver. The inner flange area may also be tuned to vibrate at a predetermined high frequency. Thus, in certain applications, where more acoustic energy is desired at high frequency, the inner flange area may be tuned to provide that extra acoustic energy. To further increase the high frequency energy generated by the compression driver, the diaphragm may be coupled to the bottom side of the inner flange area.

Abstract: This invention provides a two-stage phasing plug located within a compression driver. The two-stage phasing plug housed within the compression driver may be coupled to a horn. The two-stage phasing plug includes first and second phasing plugs. The advantages of having a two-stage phasing plug is that the first and second phasing plugs may be simpler to manufacture, cost less and the overall dimensional tolerances may be tightly controlled. The higher dimensional tolerances may be obtained because the first phasing plug may be made from a unitary work-piece, and therefore, may be tooled and cut in the same machining set up. This allows the unitary work-piece to be machined and cut very accurately when compared to assembling separate components together during the manufacturing process. Since the most dimensionally critical area is the rear side of the first phasing plug, the tolerances of the second phasing plug may not be as critical.

Abstract: An electro-magnetic loudspeaker, with dual voice coils operating in corresponding magnetic fields in annular gaps between permanent magnet pole pieces, is provided with a single short-circuited braking coil of one or more turns mounted on the voice coil form midway between the two voice coils. The braking coil has minimal effect on normal operation of the loudspeaker, but introduces an inductive braking effect from counter-EMF whenever the voice coil assembly displacement approaches a working limit in either direction, as the braking coil enters a corresponding one of the two magnetized gaps. Thus bidirectional braking/damping is accomplished in a dual coil speaker by the addition of a single braking coil, which could be simply a one turn ring; whereas bidirectional inductive braking in a speaker with a single voice coil requires two such braking coils flanking the voice coil.

Abstract: An improved electromagnetic transducer able to produce more power per mass than a conventional transducer. This increased power per mass is made possible by combining a properly designed housing, a neodymium magnet and a dual coil structure. This design dissipates the heat generated by the transducer, increasing the efficiency and power of the transducer. Also, by dissipating heat more efficiently, the transducer can be made smaller and more powerful than conventional transducers.

Abstract: For electric coil windings, particularly in moving coils such as the voice coil of a heavy duty bass loudspeaker or other electro-acoustic transducer, the present invention has found metallic materials, as alternatives to copper or aluminum in the voice coil wire, that can provide increased available maximum SPL (sound pressure level) exceeding an empirical limit, just under 120 dB/1 m, that has been found to apply to various loudspeakers of known art regardless of efficiency and structural differences. Through study of known art regarding this limitation and theoretical analysis of the factors in voice coil structure and design that limit the maximum attainable SPL, a novel basis for selecting voice coil wire material has been developed.

Abstract: Total thermal management accomplishes self-cooling from acoustic air movement in a light-weight loudspeaker system for professional sound applications: a cast aluminum front panel, forming the front baffle portion of a total enclosure, is configured to include on the front panel a horn opening, a woofer opening with a ring mount for a conventional woofer cone, a pair of bass reflex ports, and, extending rearwardly, a woofer frame with a mount for a conventional woofer driver, a horn structure with a threaded mount for a conventional horn driver, and an amplifier mounting shelf, all thermally combined by a pattern of generally vertical integral cooling vanes. The lower portions of the vanes are shaped to form structural legs of the woofer frame, and their upper portions are integrally attached to the horn. A shelf for mounting an amplifier in the speaker enclosure is formed by a transverse cooling vane.

Abstract: A self-cooled electrodynamic loudspeaker wherein the magnetic structure or pole piece has channels whereby cool air may be introduced and hot air may be exhausted to cool a voice coil by movement of the speaker diaphragm. This self-cooling results in greater power handling and output of the speaker.

Abstract: A loudspeaker with a voice coil reciprocally disposed in a magnetic gap provided with means for conducting heat outwardly from the gap comprising a flat circular web disposal in abuttment with the magnetic structure and extending between a cylindrical collar which confronts the voice coil former to a circular ring integral with the frame of the loudspeaker and including vanes extending from the web between the collar and ring. The voice coil former is limited to axial motion by a pair of spaced flat disks mounted at their centers on the central pole piece normal to the axis of motion and on the coil former at their perimeters.