The present disclosure may provide a sound-producing device comprising a diaphragm and a housing. The housing may include a first sound guide hole and a second sound guide hole. The diaphragm may be disposed in the housing. When a user wears the sound-producing device, a distance between the first sound guide hole and the ear canal opening may be smaller than a distance between the diaphragm and the ear canal opening, a range of an included angle between a connection line between the first sound guide hole and the second sound guide hole and a connection line between the center of mass of the diaphragm and the ear canal opening may be smaller than 45°, and a distance between the second sound guide hole and the ear canal opening may be greater than the distance between the diaphragm and the ear canal opening.

[Object] To make it possible to further improve acoustic characteristics. [Solution] There is provided a headphone including: a driver unit including a vibration plate; a housing configured to house the driver unit, to form an air-tightened front air chamber of which a part except for an opening for sound output is spatially blocked from the outside on a front side on which the vibration plate of the driver unit is provided, and to form a rear air chamber that has a predetermined capacity on a rear side that is the opposite side to the front side; and an acoustic tube provided in a partial region of a partition wall of the housing that constitutes the rear air chamber and configured to spatially connect the rear air chamber and the outside of the housing through a tube.

Disclosed are a tweeter and an automobile audio system. The tweeter comprises: a bracket; a diaphragm comprising a top portion and an edge ring; a magnetic motor system; and a voice coil. A first cavity is formed between the top portion of the diaphragm, an inner wall of the voice coil, and the magnetic motor system. The bracket has an annular inner flange and an annular outer flange, the edge ring of the diaphragm is connected to the outer flange of the bracket, and the magnetic motor system is connected to the inner flange of the bracket, so that a second cavity is formed between the edge ring of the diaphragm, an outer wall of the voice coil, and the bracket. A through hole is opened on the voice coil, and the first cavity is in communication with the second cavity by the through hole.

Techniques are provided for generating sound using a speaker mounted to an enclosure (e.g., speaker cabinet) wherein a gas pressure level (e.g., air pressure level) inside the enclosure is lower than an ambient air pressure level outside the enclosure. The reduced gas pressure level within the enclosure provides an environment with a reduced pressure level at a back side of a speaker cone of the speaker, which enhances a low frequency response for a given speaker size, while also minimizing resonant frequencies and phase cancellation issues which could otherwise occur with conventional speaker systems in which acoustic sound waves are generated at the back side of the speaker cone. A pressure compensation system is utilized counteract a force applied to the front side of the speaker cone as a result of the gas pressure level inside the enclosure being lower than the ambient air pressure level outside the enclosure.

A portable electronic device comprising: an enclosure having an enclosure wall that defines a first chamber, a second chamber and an acoustic opening from the first chamber or the second chamber; and an electroosmotic flow valve operable to open and close the acoustic opening.

The present disclosure discloses an acoustic output apparatus. The acoustic output apparatus may include an acoustic driver. The acoustic driver may include a diaphragm and a magnetic circuit structure. A front side of the acoustic driver may be formed at a side of the diaphragm away from the magnetic circuit structure. A rear side of the acoustic driver may be formed at a side of the magnetic circuit structure away from the diaphragm. The diaphragm may vibrate to cause the acoustic driver to radiate sound outward from the front side and the rear side of the acoustic driver. The acoustic output apparatus may further include a housing structure configured to carry the acoustic driver. One side of the front side and the rear side of the acoustic driver may form a cavity with the housing structure. The side of the acoustic driver forming the cavity may radiate the sound towards the cavity, and the other side of the acoustic driver may radiate the sound towards outside of the acoustic output apparatus.

An acoustic enclosure includes a housing at least partially defining an acoustic chamber for an acoustic radiator. The housing further defines an acoustic opening from the acoustic chamber to a surrounding environment. The acoustic enclosure also has a first acoustic resonator and a second acoustic resonator. The first acoustic resonator and the second acoustic resonator are acoustically coupled with the acoustic chamber in parallel relative to each other. Each of the first acoustic resonator and the second acoustic resonator modifies a frequency response of the acoustic chamber. Loudspeakers can include such an enclosure acoustically excited or driven by an electro-acoustic transducer. As well, an electronic device can include such a loudspeaker.

A retaining member for an earphone includes an outer layer of a first material surrounding an inner core of a second material. The retaining member extends from the earphone, and is curved to generally match the shape the antihelix of a human ear. The second material is harder than the first material, providing a stiffness to the retaining member that causes it to apply an upward and backward force against the antihelix when the retaining member is bent to fit under the antihelix of a particular user's ear.

A headphone includes a housing defining an enclosed volume, an electro-acoustic transducer dividing the enclosed volume into a front volume and a rear volume, a first port in the housing coupling the front volume to an ear canal of a user, a second port in the housing coupling the front volume to space outside the ear, a third port in the housing coupling the rear volume to space outside the ear, and an ear tip configured to surround the first port and seal the ear canal from space outside the ear. The second port has a diameter and a length that provide an acoustic mass with an acoustic impedance with a high reactive component and a low resistive component.

A loudspeaker system (50) has a front loudspeaker enclosure (10) having at least one front loudspeaker (20) and a rear loudspeaker enclosure (30) having at least one second loudspeaker (40). The front loudspeaker enclosure (10) is in the form of a horn-loaded enclosure. The rear loudspeaker enclosure (30) is in the form of a vented high-pass enclosure.