A wearable loudspeaker includes a magnetic-flux-carrying housing that houses an acoustic sealing structure that separates an interior of the housing into a back volume and a front volume acoustically coupled to a sound port. A first coil is retained in the front volume and comprises a first winding about a corresponding first magnetic core. A second coil is retained in the back volume and comprises a second winding about a corresponding second magnetic core. Opposing surfaces of the first and second magnetic cores have opposite magnetic polarities and produce a magnetic field in a gap between the first and second coils. A magnetic-flux-carrying armature is movably located in the gap and fastened to the acoustic sealing structure. Sound is emitted from the sound port when the armature moves the acoustic sealing structure in the gap.

An apparatus includes a surface arranged to be mechanically displaced, a first permanent magnet coupled with the surface, at least one supporting member for supporting the surface, a base, a second permanent magnet, a coil coupled with the second magnet, and a signal port electrically coupled with the coil. An electrical signal is configured to travel between the signal port and the coil. The electrical signal in the coil is proportional to mechanic displacement of the surface when a force equilibrium state of the surface is broken by the electrical signal in the coil or the mechanic displacement of the surface from a position of the force equilibrium state The coil is arranged at least partially between the first magnet and the second magnet or around one of the first magnet, the second magnet. Either the same or different polarities of the first and second magnets are arranged to directly face each other at a distance.

An apparatus includes a surface arranged to be mechanically displaced, a first permanent magnet coupled with the surface, at least one supporting member for supporting the surface, a base, a second permanent magnet, a coil coupled with the second magnet, and a signal port electrically coupled with the coil. An electrical signal is configured to travel between the signal port and the coil. The electrical signal in the coil is proportional to mechanic displacement of the surface when a force equilibrium state of the surface is broken by the electrical signal in the coil or the mechanic displacement of the surface from a position of the force equilibrium state The coil is arranged at least partially between the first magnet and the second magnet or around one of the first magnet, the second magnet. Either the same or different polarities of the first and second magnets are arranged to directly face each other at a distance.

A compression driver includes a magnet assembly and a waveguide mounted to the magnet assembly, the waveguide having a first side, an opposed second side, and a central aperture forming an exit of the compression driver. An annular diaphragm is disposed above the magnet assembly and adjacent the second side of the waveguide, the diaphragm having an external flat portion generally coplanar with an internal flat portion. A compression chamber is defined between the diaphragm and the second side of the waveguide, the second side of the waveguide having a final segment that tapers toward the central aperture, wherein part of the diaphragm is loaded by the compression chamber and part of the diaphragm radiates directly to the exit of the compression driver.

A compression driver includes a magnet assembly and a waveguide mounted to the magnet assembly, the waveguide having a first side, an opposed second side, and a central aperture forming an exit of the compression driver. An annular diaphragm is disposed above the magnet assembly and adjacent the second side of the waveguide, the diaphragm having an external flat portion generally coplanar with an internal flat portion. A compression chamber is defined between the diaphragm and the second side of the waveguide, the second side of the waveguide having a final segment that tapers toward the central aperture, wherein part of the diaphragm is loaded by the compression chamber and part of the diaphragm radiates directly to the exit of the compression driver.

An electric motor including two magnetic assemblies each having an even number of magnets in a circular arrangement, the magnets arranged in a bucking configuration with like poles directed at each other. There are a plurality of ferrous members for each of the magnetic assemblies arranged between each of the magnets. The ferrous members having a face that is directed radially toward a face of another ferrous member of the corresponding magnetic assembly. An electromagnetic assembly has a plurality of electromagnetic members arranged in a generally circular arrangement and is located radially between the two magnetic assemblies. Each electromagnetic member has a ferrous element with an electrical conductor wound around the ferrous element, each ferrous element having an inward and outward face respectively being directed to the ferrous members of the two magnetic assemblies as they pass each other as the magnet assemblies rotate relative to the electromagnetic assembly.

Disclosed is a coil module, comprising: a vibrating membrane suspended on an air chamber defined and supported by a first substrate, at least one planar coil, embedded in the vibrating membrane, and at least a soft magnet, embedded in the vibrating membrane and disposed surrounding at least a portion of a contour of the planar coil; wherein a substantial portion of the planar coil locates at substantially the same plane where a portion of the soft magnet is arranged.

Disclosed is a coil module, comprising: a vibrating membrane suspended on an air chamber defined and supported by a first substrate, at least one planar coil, embedded in the vibrating membrane, and at least a soft magnet, embedded in the vibrating membrane and disposed surrounding at least a portion of a contour of the planar coil; wherein a substantial portion of the planar coil locates at substantially the same plane where a portion of the soft magnet is arranged.

Disclosed is a coil module, comprising: a vibrating membrane suspended on an air chamber defined and supported by a first substrate, at least one planar coil, embedded in the vibrating membrane, and at least a soft magnet, embedded in the vibrating membrane and disposed surrounding at least a portion of a contour of the planar coil; wherein a substantial portion of the planar coil locates at substantially the same plane where a portion of the soft magnet is arranged. A microspeaker and a method for preparing the same are also disclosed.

Disclosed is a coil module, comprising: a vibrating membrane suspended on an air chamber defined and supported by a first substrate, at least one planar coil, embedded in the vibrating membrane, and at least a soft magnet, embedded in the vibrating membrane and disposed surrounding at least a portion of a contour of the planar coil; wherein a substantial portion of the planar coil locates at substantially the same plane where a portion of the soft magnet is arranged. A microspeaker and a method for preparing the same are also disclosed.