Abstract: A thermally conductive chimney tube extends through a loudspeaker cabinet that encloses a volume of air heated by a speaker driver. The open ends of the chimney are outside the cabinet. A column of air within the chimney is in contact with the external ambient air, but sealed off from the enclosed volume of air. As the speaker driver heats the enclosed volume of air, the material of the chimney transfers the heat to the column of air, which rises and carries the heat away into the external ambient air, cooling the inside of the loudspeaker cabinet and thus cooling the speaker driver.

Abstract: An electromagnetic transducer such as an audio speaker which includes an asymmetric diaphragm to deliver smooth frequency response with reduced distortion by reduction of common modes in the diaphragm. Other benefits such as asymmetric directivity patterns can be realized. The asymmetric cone has a perimeter OD at which a surround may be coupled, and an ID at which a bobbin or spacer may be coupled. The center of the ID is not coincident with the center of the OD. The transducer further includes a stabilization mechanism for reducing rocking of the diaphragm assembly. The stabilization mechanism may include mass balancing of the diaphragm and/or adjustments to the location or symmetry of the suspension components.

Abstract: An electromagnetic transducer such as a tweeter audio speaker, having a very low density diaphragm constructed of a nanoporous material such as aerogel or the like. The solid aerogel diaphragm has improved rigidity and reduced susceptibility to breakup modes. The aerogel may be provided with a skin of e.g. metal, plastic, or oxide to protect it, and it may be built by filling a conventional cone. The skin may encapsulate part or all of the aerogel body's surface, and it may further encapsulate the bobbin, or even the entire voice coil assembly. The nanoporous material comprises a very large percentage of the diaphragm's overall volume, giving the diaphragm a very low overall mass density with respect to conventional diaphragms. This allows diaphragm configurations, such as solid filled spheres, which have excellent stiffness without suffering from the large mass that such shapes would mandate if constructed from conventional materials.

Abstract: An electromagnetic transducer motor structure such as for an audio speaker. The motor structure has a non-magnetically conductive heatsink in the middle of its magnetic circuit members. A set of magnetically conductive members extend through the heatsink to conduct magnetic flux across the thickness of the heatsink, completing the magnetic circuit. The heatsink includes spokes or webs which extend between these members, to carry heat away from the voice coil area to a heatsink body outside the motor structure. The heatsink may optionally include an inner ring to sink eddy currents generated by the voice coil, reducing eddy current heating of the less thermally conductive and more electrically resistive plates and magnets of the motor structure. The heatsink body may optionally form the basket of the speaker.