A dynamic balance speaker includes a diaphragm, a voice coil, a printed circuit board, a base frame, a first tuning paper, a washer, a main magnet, and a U-yoke. The base frame is formed with a plurality of spaced first vents and a mounting groove in the middle between adjacent two of the first vents. The mounting groove is provided with positioning grooves. The printed circuit board is provided with positioning portions. The positioning portions are fixed in the positioning grooves, respectively. The voice coil is provided with a pair of lead wires. The lead wires are symmetrical to the center of the printed circuit board. The dynamic balance speaker provides good sound quality.

A dome material, a diaphragm and a speaker are provided. The speaker includes the diaphragm made of the dome material. The dome material includes an intermediate layer, an adhesive layer, a film layer, and a surface layer. The adhesive layer, the film layer, and the surface layer are sequentially stacked on the intermediate layer in a direction away from the intermediate layer. The intermediate layer is formed by a foamed material. A thickness of the adhesive layer is 3-20 μm. The film layer is adhered to the intermediate layer via the adhesive layer. A thickness of the film layer is 2-20 μm. The surface layer adopts fiber prepreg including fiber and resin, the fiber is unidirectionally arranged, and a weight percentage of the fiber is 20%-50%. A surface density of the fiber prepreg is 10-100 g/m.sup.2.

A composite material for producing an acoustic membrane, wherein the composite material comprises a silicone layer comprising an at least partially uncured silicone rubber and a support layer, wherein the support layer is adjacent to the silicone layer, as well as a method of preparing such a composite material and a process for producing an acoustic membrane from such a composite material.

A microphone, comprising at least two electrodes, spaced apart, configured to have a magnetic field within a space between the at least two electrodes; a conductive fiber, suspended between the at least two electrodes; in an air or fluid space subject to waves; wherein the conductive fiber has a radius and length such that a movement of at least a central portion of the conductive fiber approximates an oscillating movement of air or fluid surrounding the conductive fiber along an axis normal to the conductive fiber. An electrical signal is produced between two of the at least two electrodes, due to a movement of the conductive fiber within a magnetic field, due to viscous drag of the moving air or fluid surrounding the conductive fiber. The microphone may have a noise floor of less than 69 dBA using an amplifier having an input noise of 10 nV/√Hz.

A speaker diaphragm includes a first polymer and a second polymer. The first polymer and the second polymer undergo phase separation. The first polymer is a polyolefin, and the second polymer is a thermoplastic resin being immiscible with the polyolefin. One of either the polyolefin or the thermoplastic resin constitutes a sea phase, and another one of either the polyolefin or the thermoplastic resin constitutes island phases being interspersed in the sea phase.

In at least one embodiment, a loudspeaker assembly for a vehicle is provided. The assembly includes a diaphragm; a loudspeaker, and a carrier. The loudspeaker includes a first end for being positioned in a first area of the vehicle that is exposed to external ambient noise to the vehicle and a second end for being positioned in a second area of the vehicle that is exposed directly within an interior cabin of the vehicle to provide desired audio along a first axis to the interior cabin. The carrier is attached to the second end of the loudspeaker and includes noise absorption material to prevent the external ambient noise from entering into the vehicle. The carrier defines a plurality of openings positioned on an outer perimeter thereof to enable the desired audio to enter into the interior cabin along a second axis that is different than the first axis.

In at least one embodiment, a loudspeaker assembly for a vehicle is provided. The assembly includes a diaphragm; a loudspeaker, and a carrier. The loudspeaker includes a first end for being positioned in a first area of the vehicle that is exposed to external ambient noise to the vehicle and a second end for being positioned in a second area of the vehicle that is exposed directly within an interior cabin of the vehicle to provide desired audio along a first axis to the interior cabin. The carrier is attached to the second end of the loudspeaker and includes noise absorption material to prevent the external ambient noise from entering into the vehicle. The carrier defines a plurality of openings positioned on an outer perimeter thereof to enable the desired audio to enter into the interior cabin along a second axis that is different than the first axis.

A speaker diaphragm includes a mixed layer. The mixed layer includes cellulose nanofibers, and polyparaphenylenebenzobisoxazole fibers. An average length of the polyparaphenylenebenzobisoxazole fibers is 0.5 mm or more and 4.0 mm or less.

A speaker diaphragm includes a cone formed of a first material including first fibers derived from a plant and a first resin for binding the first fibers together, and an edge portion which is positioned at an outer peripheral portion of the cone and formed of a second material including a second resin, in which the cone and the edge portion are integrally formed. In addition, at least one of the content and the composition of the first resin and the second resin is different.

A microphone, comprising at least two electrodes, spaced apart, configured to have a magnetic field within a space between the at least two electrodes; a conductive fiber, suspended between the at least two electrodes; in an air or fluid space subject to waves; wherein the conductive fiber has a radius and length such that a movement of at least a central portion of the conductive fiber approximates an oscillating movement of air or fluid surrounding the conductive fiber along an axis normal to the conductive fiber. An electrical signal is produced between two of the at least two electrodes, due to a movement of the conductive fiber within a magnetic field, due to viscous drag of the moving air or fluid surrounding the conductive fiber. The microphone may have a noise floor of less than 69 dBA using an amplifier having an input noise of 10 nV/√Hz.