A MEMS loudspeaker arrangement for generating sound waves in the audible wavelength spectrum includes a housing that defines a sound-conducting channel and a sound outlet arranged at the end of the sound-conducting channel. At least two MEMS loudspeakers are arranged in the interior of the housing so that they generate sound waves through the sound-conducting channel to the sound outlet. One of the MEMS loudspeakers is disposed downstream of the other in the direction of the sound outlet. A control unit is connected to control the MEMS loudspeakers so as to increase the maximum loudness of the MEMS loudspeaker arrangement. The first of the two MEMS loudspeakers is controlled to function as a sound generator for generating an initial wave, and the second MEMS loudspeaker is controlled to function as a sound amplifier for amplifying the initial wave.

A MEMS loudspeaker arrangement for generating sound waves in the audible wavelength spectrum includes a housing that defines a sound-conducting channel and a sound outlet arranged at the end of the sound-conducting channel. At least two MEMS loudspeakers are arranged in the interior of the housing so that they generate sound waves through the sound-conducting channel to the sound outlet. One of the MEMS loudspeakers is disposed downstream of the other in the direction of the sound outlet. A control unit is connected to control the MEMS loudspeakers so as to increase the maximum loudness of the MEMS loudspeaker arrangement. The first of the two MEMS loudspeakers is controlled to function as a sound generator for generating an initial wave, and the second MEMS loudspeaker is controlled to function as a sound amplifier for amplifying the initial wave.

Disclosed is an acoustic transducer for converting a sound signal into an electric signal, including a mobile element movable under the effect of the sound signal, a fixed element opposite the mobile element, a recess, and a dissipative element between the mobile and fixed elements. The coupled system has a natural frequency corresponding to a resonance frequency of the transducer set at maximum sensitivity. The mobile element, the fixed element, the dissipative element and the recess are configured so the quality factor of the acoustic transducer>2. The recess has a straight prismatic, cylindrical, or frustoconical shape, the mobile element forming a first base of the prism, cylinder, or frustum, the fixed element being inside the prism, cylinder or frustum, over the second base of the prism, cylinder or frustum. Such a transducer also incorporates an analogue filtering function for filtering the signal around the natural frequency of same.

A fixed electrode configured to face a diaphragm and forming a capacitance with the diaphragm, including a plurality of protrusions formed by plastic deformation on one surface of the fixed electrode that is to face the diaphragm, so as to protrude toward the diaphragm.

A fixed electrode configured to face a diaphragm and forming a capacitance with the diaphragm, including a plurality of protrusions formed by plastic deformation on one surface of the fixed electrode that is to face the diaphragm, so as to protrude toward the diaphragm.

An electrostatic transducer including a membrane, a first electrode and a second electrode. The first electrode is disposed parallel to the membrane. The membrane is configured to respond mechanically to a varying first electric field in accordance with respective electric potentials applied between the first electrode and the membrane. The second electrode is disposed parallel to the membrane opposite from the first electrode. The membrane is configured to respond mechanically to a varying second electric field in accordance with respective electric potentials between the second electrode and the membrane. The first and second electrodes have through holes configured for acoustic transmission to and from the membrane. The housing includes: (i) a nozzle configured for acoustic transmission from the membrane through the holes of the first electrode to an ear canal and (ii) an aperture configured to provide acoustic transmission through the holes of the second electrode between the membrane and air external to the housing.

A two-port air pump speaker that includes at least two active, phase-modulated, bi-directional shutters and an ultrasonic pumping chamber having at least two ports; a first port facing towards the listener, the forward port, and a second port facing another direction, the backward port which may be behind an acoustic baffle or inside a speaker enclosure. A two-port speaker with two active steering shutters can create continuous bi-directional airflow which leads to low distortion reproduction of low audio frequencies. The same improved design can be used also for other applications where acoustic modulation is required, especially in ultrasonic frequencies.

A two-port air pump speaker that includes at least two active, phase-modulated, bi-directional shutters and an ultrasonic pumping chamber having at least two ports; a first port facing towards the listener, the forward port, and a second port facing another direction, the backward port which may be behind an acoustic baffle or inside a speaker enclosure. A two-port speaker with two active steering shutters can create continuous bi-directional airflow which leads to low distortion reproduction of low audio frequencies. The same improved design can be used also for other applications where acoustic modulation is required, especially in ultrasonic frequencies.

A MEMS loudspeaker device and a corresponding manufacturing method are described. The MEMS loudspeaker device includes a first substrate having a first front side and a first rear side, which includes a first rear side cavity, which is at least partially covered by a sound generation device; a second substrate having a second front side and a second rear side, which includes a second rear side cavity, which is covered by a first perforated plate device; the second rear side being bonded to the first front side in such a way that the second rear side cavity is situated above the sound generation device; and a second perforated plate device, which is attached above the first perforated plate device; at least one of the first perforated plate device and of the second plate device being elastically deflectable in such a way that a passage of sound of the sound generation device may be modulated by an interaction of the first perforated plate device and the second perforated plate device.

A MEMS loudspeaker device and a corresponding manufacturing method are described. The MEMS loudspeaker device includes a first substrate having a first front side and a first rear side, which includes a first rear side cavity, which is at least partially covered by a sound generation device; a second substrate having a second front side and a second rear side, which includes a second rear side cavity, which is covered by a first perforated plate device; the second rear side being bonded to the first front side in such a way that the second rear side cavity is situated above the sound generation device; and a second perforated plate device, which is attached above the first perforated plate device; at least one of the first perforated plate device and of the second plate device being elastically deflectable in such a way that a passage of sound of the sound generation device may be modulated by an interaction of the first perforated plate device and the second perforated plate device.