A high-frequency (HF) sound-emitting device is provided, which comprises an open-ended hollow housing, an acoustic oscillator arranged inside the hollow housing and configured to generate HF sound oscillations, and a sound-emitting membrane attached to the acoustic oscillator. The sound-emitting membrane comprises a paper-based composite material layer, a metal layer, and a coating layer. The paper-based composite material layer has a top surface facing the open end of the hollow housing. The metal layer is provided on the top surface of the paper-based composite material layer and configured to reproduce the HF sound oscillations. The coating layer is provided on the metal layer and has one or more slots through which the metal layer is visible. The coating layer is made of a material incapable of reproducing the HF sound oscillations. With this configuration, the sound-emitting device may emit a fractal-polarized sound field.

A vibration component for loudspeakers includes a base layer, an intermediate layer, and a coating layer. The base layer has a front face and a rear face, has a first density, and is formed of a paper body containing a plurality of fibers. The intermediate layer has a first face joined to the front face of the base layer, and a second face on a reverse side of the intermediate layer from the first face, has a second density higher than the first density, and includes a plurality of cellulose fibers as a main component. The coating layer is provided on the second face of the intermediate layer, and includes an inorganic powder formed of a plurality of inorganic fine particles.

A loudspeaker diaphragm includes a main material containing molecules each having a hydroxyl group, and a diamondoid derivative. The diamondoid derivative contains molecules each having two or more hydrogen-bonding functional groups. Each of the two or more hydrogen-bonding functional groups in each of the molecules of the diamondoid derivative is bonded to the hydroxyl group in each of the molecules of the main material.

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 loudspeaker diaphragm includes a cone having a curved surface from the outer to the inner periphery, and an annular edge of which inner peripheral part is bonded to the front side of the outer peripheral part of the cone. When seen from the front, the outer periphery of the cone is defined by smooth connection of three larger-diameter parts tangent to a first circle with a larger diameter, and three smaller-diameter parts each located between adjacent two of the three larger-diameter parts and tangent to a second circle with a smaller diameter. In the cone, a shape defined by connecting together points at the same position on the central axis is more circular as the points approach the inner periphery from the outer periphery. The inner periphery of the edge has a smaller radius than the second circle.

A sound system is provided with a headphone that includes a transducer and at least one microphone. The sound system also includes an equalization filter and a loop filter circuit. The equalization filter is adapted to equalize an audio input signal based on at least one predetermined coefficient. The loop filter circuit includes a leaky integrator circuit that is adapted to generate a filtered audio signal based on the equalized audio input signal and a feedback signal indicative of sound received by the at least one microphone, and to provide the filtered audio signal to the transducer.

A loudspeaker diaphragm includes a base layer and a coating layer. The base layer contains natural fibers. The coating layer is formed on at least one of surfaces of the base layer. The coating layer is composed of chitin nanofibers each having a higher elastic modulus than that of the base layer.

A speaker assembly includes a sound chamber, a speaker and a diaphragm. The speaker is set at one end of the sound chamber. The diaphragm is set at one side of the sound chamber. The sound chamber, the speaker and the diaphragm form a closed cavity, thus to reduce the high tone from the speaker to a mid-bass pitch. An electronic device using the speaker assembly is also provided.

An assembly (10) includes a first support member (15) having a plurality of first apertures (50); a second support member (20) having a plurality of second apertures (55); and a polymer membrane (25) disposed between the first support member (15) and the second support member (20). The polymer membrane (25) is spaced from the first support member (15) by a first distance (30) and from the second support member (20) by a second distance (35). Each of the first distance or the second distance is from 10/|iri to 100/|iri. The assembly provides a standard deviation of insertion loss of 0.8 dB or less over a frequency range of 200 Hz to 10,000 Hz after a water entry pressure (WEP) test.

Disclosed is a speaker device, comprising a vibration system, a magnetic circuit system, and an auxiliary system for accommodating and fixing the vibration system and the magnetic circuit system. The vibration system comprises a diaphragm, the auxiliary system comprises a front cover, a side of the front cover is provided a waterproof pad, said side being away from the vibration system. The diaphragm are bonded to the front cover and the waterproof pad by integrally injection molding. The speaker device of the present invention satisfies terminal waterproof requirements for IPX7 and above, and has a good waterproof effect. Besides, a production process of the waterproof speaker device is simplified, production efficiency is increased, production costs of the speaker device are decreased, and the reprocessed product yield of the speaker device is increased.