A sound producing device includes at least one air pulse generating element. Each of the at least one air pulse generating element includes a membrane, a first air chamber and at least one opening, wherein a chamber pressure exists in the first air chamber. The membrane is actuated to change the chamber pressure of the first air chamber to generate a plurality of air pulses, the air pulses are propagated through the at least one opening, the air pulses produce a non-zero offset in terms of sound pressure level, and the non-zero offset is a deviation from a pressure value of an ambient pressure outside the sound producing device.

A sound producing device includes at least one air pulse generating element. Each of the at least one air pulse generating element includes a membrane, a first air chamber and at least one opening, wherein a chamber pressure exists in the first air chamber. The membrane is actuated to change the chamber pressure of the first air chamber to generate a plurality of air pulses, the air pulses are propagated through the at least one opening, the air pulses produce a non-zero offset in terms of sound pressure level, and the non-zero offset is a deviation from a pressure value of an ambient pressure outside the sound producing device.

A sound producing device includes a first sound producing cell, driven by a first driving signal and configured to produce a first acoustic sound on a first audio band, and a second sound producing cell, driven by a second driving signal and configured to produce a second acoustic sound on a second audio band different from the first audio band. A first membrane of the first sound producing cell and a second membrane of the second sound producing cell are Micro Electro Mechanical System fabricated membranes. The first audio band is upper bounded by a first maximum frequency; the second audio band is upper bounded by a second maximum frequency. A first resonance frequency of the first membrane is higher than the first maximum frequency of the first driving signal. A second resonance frequency of the second membrane is higher than the second maximum frequency of the second driving signal.

A sound producing device includes a first sound producing cell, driven by a first driving signal and configured to produce a first acoustic sound on a first audio band, and a second sound producing cell, driven by a second driving signal and configured to produce a second acoustic sound on a second audio band different from the first audio band. A first membrane of the first sound producing cell and a second membrane of the second sound producing cell are Micro Electro Mechanical System fabricated membranes. The first audio band is upper bounded by a first maximum frequency; the second audio band is upper bounded by a second maximum frequency. A first resonance frequency of the first membrane is higher than the first maximum frequency of the first driving signal. A second resonance frequency of the second membrane is higher than the second maximum frequency of the second driving signal.

A MEMS device includes a layer stack having a plurality of MEMS layers arranged along a layer stack direction. The MEMS device includes a movable element formed in a first MEMS layer and arranged between a second MEMS layer and a third MEMS layer of the layer stack. A driving unit is further provided, comprising a first drive structure mechanically firmly connected to the movable element and a second drive structure mechanically firmly connected to the second MEMS layer. The driving unit is configured to generate on the movable member a drive force perpendicular to the layer stack direction, and the drive force is configured to deflect the movable member.

An acoustic device (1), comprises: a container (2); a passive resonator, including a suspension (3) connected to the container (2) and a radiator (4) connected to the suspension (3), where the suspension (3) is configured to allow the radiator (4) to vibrate relative to the container (2), a structure (5) having at least a first connecting point (51), where it is connected to the radiator (4), and a second connecting point (52), where it is connected to the container (2), the structure (5) being movable alternately between a first position and a second position, responsive to a vibration of the radiator (4); one or more masses (61, 62), spaced from the radiator (4) and associated with the vibrating structure (5).

An acoustic device (1), comprises: a container (2); a passive resonator, including a suspension (3) connected to the container (2) and a radiator (4) connected to the suspension (3), where the suspension (3) is configured to allow the radiator (4) to vibrate relative to the container (2), a structure (5) having at least a first connecting point (51), where it is connected to the radiator (4), and a second connecting point (52), where it is connected to the container (2), the structure (5) being movable alternately between a first position and a second position, responsive to a vibration of the radiator (4); one or more masses (61, 62), spaced from the radiator (4) and associated with the vibrating structure (5).

Embodiments of the present disclosure describe an MEMS sound transducer having an actuator and a structure surrounding the actuator, wherein the actuator is separated from the surrounding structure by one or several slits. Furthermore, the sound transducer includes at least one first diaphragm arranged on the actuator along at least one of the one or several slits; and at least one second diaphragm arranged on the surrounding structure along the slit of the one or several slits.

Embodiments of the present disclosure describe an MEMS sound transducer having an actuator and a structure surrounding the actuator, wherein the actuator is separated from the surrounding structure by one or several slits. Furthermore, the sound transducer includes at least one first diaphragm arranged on the actuator along at least one of the one or several slits; and at least one second diaphragm arranged on the surrounding structure along the slit of the one or several slits.

The present disclosure discloses a MEMS speaker including a housing with a receiving space; a MEMS speaker chip with an inner cavity, accommodated in the receiving space and connected with the housing, the MEMS speaker chip dividing the receiving space into a first cavity and a second cavity communicating with the inner cavity; a sound hole communicating with the first cavity or the second cavity; and a damping mesh connected to the housing and covering the sound hole; wherein sounds emitted by the MEMS speaker chip transmit outward through the sound hole and the damping mesh. Compared with the related art, MEMS speaker disclosed by the present disclosure has a better reliability.