The present application provides a method of manufacturing a resonant panel (200) of a flat panel loudspeaker. The method comprises: pressing a resonant panel blank between a first pressing surface (302) and a second pressing surface of a press, whereby to form the resonant panel (200) of the flat panel loudspeaker. The second pressing surface substantially opposes the first pressing surface (302). The first pressing surface (302) comprises at least one tool relief region (306, 312, 314, 316, 318), whereby to form at least one corresponding respective panel relief region (206, 212, 214, 216, 218) in a surface of the resonant panel (200).

A speaker device includes a housing body, a speaker driver and a passive radiator. The housing body is formed with a first sound hole and a second sound hole respectively opening in two opposite directions. The speaker driver is disposed in the housing body, is located adjacent to the first sound hole, and is adapted to generate sound. The passive radiator is disposed in the housing body, is located adjacent to the second sound hole, and is adapted to generate sound. The first sound hole and the second sound hole are adapted for respectively allowing the sound generated by the speaker driver and the sound generated by the passive radiator to travel out from the housing body respectively in two opposite directions therethrough.

Provided are a hierarchical porous ZSM-5 molecular sieve and a preparation method therefor. The molecular sieve comprises micropores and mesopores, wherein the pore size of the micropores is 0.5-1.8 nm, the pore size of the mesopores is 4-30 nm, and the particle size is 0.3-4 μm. The molecular sieve is prepared by using a hemicellulose as a hard template agent. Also provided are a hierarchical porous HZSM-5 molecular sieve, which is obtained by subjecting the ZSM-5 molecular sieve to ion exchange with an ammonium chloride solution, and the use of ZSM-5 and HZSM-5 molecular sieves in the preparation of a sound-absorbing material, the sound-absorbing material made from the molecular sieve, and a speaker loaded with the sound-absorbing material. After being prepared into sound-absorbing particles, the molecular sieve can more effectively improve the absorption and desorption performances of air molecules, improve the low-frequency response of a speaker, improve the acoustic performance of the speaker, and improve the acoustic improvement stability of sound-absorbing particles in the speaker.

A speaker (20) includes a cabinet (21) extending along a longitudinal axis (X) between a first and a second end (21a, 21b). The cabinet (21) includes a side wall surrounding an internal volume and provided with an opening to place the internal volume in communication with an outside environment. The speaker (20) also includes a sound transducer (22) and a connection circuit (23) configured to receive a signal and to transmit the signal to the sound transducer (22). The speaker (20) also includes a first and a second passive resonator (24, 25) each including a vibrating panel (24a, 25a). The vibrating panels (24a, 25a) are positioned in the internal volume, with respective first faces facing each other and respective second faces opposite the first faces. The internal volume includes a first, closed air volume (V1) delimited by an inside surface of the cabinet (21) and by the second faces of the vibrating panels (24a, 25a). The internal volume also includes a second air volume (V2), delimited by the first faces of the vibrating panels (24a, 25a) and open towards the outside environment through the opening.

A modular speaker (100) includes a main module (200) defining a speaker (20) and including a cabinet (21) extending along a longitudinal axis (X) between a first and a second end (21a, 21b), a sound transducer (22), provided at the first end (21a) of the cabinet (21) and a connection circuit (23), provided at the second end (21b) of the cabinet (21). The modular speaker (100) also includes a rear module (300) selectable from a plurality of rear modules (300) and connectable reversibly to the second end (21b) of the cabinet (21) and a front module (400), defining an acoustic accessory selectable from a plurality of front modules (400) and connectable reversibly to the first end (21a) of the cabinet (21).

An outer structure of a magnetic circuit is held inside a holder recess of a magnetic circuit holder of a frame. A pressing portion is screw-fixed to a mounting surface of the magnetic circuit holder. Elastically deformable pressing arms are formed at the pressing portion, and the pressing arms press a restriction surface of the outer structure of the magnetic circuit.

Provided in this disclosure is an acoustic adapter which includes an interior enclosure for substantially surrounding a back of a speaker driver and for defining a predetermined three-dimensional interior volume (3DV1) around the back of the speaker driver to thereby act as a vibration dampener. An exterior enclosure is provided having a configuration that corresponds to a configuration of the interior enclosure and spaced apart from the interior enclosure to define a restricted two-dimensional volume (2DV) outside the three-dimensional interior volume. An aperture is formed in the interior surface of the enclosure for admitting sound into the two-dimensional volume. A foam material is received within the two-dimensional volume (2DV) for at least coating an inner surface of the exterior enclosure, to provide a frictional surface for damping the sound admitted into the two-dimensional volume.

In one embodiment of an audio system, a transducer can be coupled to a passive acoustic directional amplifier to provide various benefits and improvements, including improvements to: speech intelligibility, signal-to-noise ratio, effective equivalent input noise, at-a-distance acoustic signal reception, and directional preference. In another embodiment, the shape of an interior surface of a passive acoustic directional amplifier is provided. In another embodiment, the material properties of an interior surface of a passive acoustic directional amplifier are provided.

A speaker module includes a casing and a speaker unit. The casing has a sound outlet. The speaker unit is arranged in the casing, the speaker unit and the sound outlet are arranged along a transverse axis, and the speaker unit includes a bearing base, a first speaker assembly, and a second speaker assembly. The first and second speaker assemblies are disposed on the bearing base. The first speaker assembly and the second speaker assembly are symmetrical relative to the bearing base. A first sound cavity is formed between the casing and the first speaker assembly, a second sound cavity is formed between the casing and the second speaker assembly, the first sound cavity and the second sound cavity are communicated with the sound outlet, and the first sound cavity and the second sound cavity have the same size and are symmetrical relative to the bearing base.

Intra-concha earphones are disclosed. In an embodiment, an intra-concha earphone includes a housing having a rear space divided into a back volume, a bass duct, and a vent chamber between a driver and a rear wall. The vent chamber may be acoustically coupled with the back volume through both an acoustic port and the bass duct. Furthermore, the vent chamber may be acoustically coupled with a surrounding environment through a vent port, which may be a sole acoustic opening in the rear wall. Thus, sound emitted by the driver may propagate through the acoustic port and the bass duct to meet in the vent chamber before being discharged through the vent port to the surrounding environment. Other embodiments are also described and claimed.