A microphone module disposed in an electronic device for reducing echo noise. The microphone module includes a casing, a first diaphragm disposed in the casing, a second diaphragm disposed in the casing and a substrate disposed between the first diaphragm and the second diaphragm and joined to the casing to define a first space and a second space which are isolated and separated from each other. The first diaphragm is disposed in the first space, the second diaphragm is disposed in the second space, and the substrate is electrically connected with the first diaphragm and the second diaphragm.

A microphone module disposed in an electronic device for reducing echo noise. The microphone module includes a casing, a first diaphragm disposed in the casing, a second diaphragm disposed in the casing and a substrate disposed between the first diaphragm and the second diaphragm and joined to the casing to define a first space and a second space which are isolated and separated from each other. The first diaphragm is disposed in the first space, the second diaphragm is disposed in the second space, and the substrate is electrically connected with the first diaphragm and the second diaphragm.

In an embodiment a device includes a substrate including an upper substrate surface and a lower substrate surface and a membrane-layer suspended above the upper substrate surface, wherein the substrate includes a recess penetrating the substrate between the lower substrate surface and the upper substrate surface, wherein the membrane-layer spans the recess, wherein the recess includes an upper recess region, an intermediate recess region, and a lower recess region, wherein the upper recess region is a part of the recess in direct vicinity to the upper substrate surface, the intermediate recess region is a part of the recess directly below the upper recess region, and the lower recess region is a part of the recess other than the upper recess region and the intermediate recess region, and wherein a cross-sectional area of the upper recess region determined parallel to the upper substrate surface is larger than a respective cross-sectional area of the intermediate recess region.

A speaker unit incorporated in a housing of an earphone includes: a frame having a cylindrical shape; a diaphragm emitting sound; and a board to which a wiring line of a coil provided to the diaphragm is connected. The frame has a space inside, and the diaphragm and the board are placed inside the frame with the space interposed between the diaphragm and the board.

A speaker unit incorporated in a housing of an earphone includes: a frame having a cylindrical shape; a diaphragm emitting sound; and a board to which a wiring line of a coil provided to the diaphragm is connected. The frame has a space inside, and the diaphragm and the board are placed inside the frame with the space interposed between the diaphragm and the board.

A sound producing structure includes: a frame body, a magnetic circuit system, a first diaphragm, and a second diaphragm. The frame body includes a receiving cavity, and the receiving cavity includes a first opening and a second opening that are located on two opposite sides of the frame body. The magnetic circuit system is located in the receiving cavity, and the magnetic circuit system includes a first magnetic channel and a second magnetic channel that are isolated from each other. The first diaphragm is disposed facing the first opening, a first voice coil is disposed on the first diaphragm, and a portion of the first voice coil extends into the first magnetic channel. The second diaphragm is disposed facing the second opening, a second voice coil is disposed on the second diaphragm, and a portion of the second voice coil extends into the second magnetic channel.

A sound producing structure includes: a frame body, a magnetic circuit system, a first diaphragm, and a second diaphragm. The frame body includes a receiving cavity, and the receiving cavity includes a first opening and a second opening that are located on two opposite sides of the frame body. The magnetic circuit system is located in the receiving cavity, and the magnetic circuit system includes a first magnetic channel and a second magnetic channel that are isolated from each other. The first diaphragm is disposed facing the first opening, a first voice coil is disposed on the first diaphragm, and a portion of the first voice coil extends into the first magnetic channel. The second diaphragm is disposed facing the second opening, a second voice coil is disposed on the second diaphragm, and a portion of the second voice coil extends into the second magnetic channel.

A MEMS capacitive microphone according to the present invention is configured such that a support plate 120 from which an inside thereof has been removed in a plane is attached to supports 110 each having an end fixed to a substrate 100, an anchor 130 is attached to an edge region of the support plate 120, an edge of a diaphragm 200 is supported by the anchor 130, and a “substrate-free area” includes the anchor 130 in a plan view, and pluralities of moving comb fingers 300 and stiffeners are attached to a top or bottom or a top and bottom of the diaphragm 200, and the supports 110 support the stationary comb fingers 400 arranged at predetermined intervals on both sides of the moving comb fingers 300 in a plan view.

Apparatus configured to predict a diaphragm deflection signal, block-by-block, in overlapping time blocks based on the loudspeaker signal to obtain one diaphragm deflection signal block per time block. The apparatus is configured to determine a temporal position of a maximum deflection of a current diaphragm deflection signal block of a current time block within an overlap area with a subsequent time block and to calculate a level up to which the current diaphragm deflection signal block can be controlled without diaphragm over-deflection for the current time block by considering a comparison of the current diaphragm deflection signal block with a subsequent diaphragm deflection signal block or an estimation of the subsequent diaphragm deflection signal block from the current diaphragm deflection signal block at the temporal position. The apparatus is configured to attenuate the current diaphragm deflection signal block and to synthesize a modified loudspeaker signal.

Apparatus configured to predict a diaphragm deflection signal, block-by-block, in overlapping time blocks based on the loudspeaker signal to obtain one diaphragm deflection signal block per time block. The apparatus is configured to determine a temporal position of a maximum deflection of a current diaphragm deflection signal block of a current time block within an overlap area with a subsequent time block and to calculate a level up to which the current diaphragm deflection signal block can be controlled without diaphragm over-deflection for the current time block by considering a comparison of the current diaphragm deflection signal block with a subsequent diaphragm deflection signal block or an estimation of the subsequent diaphragm deflection signal block from the current diaphragm deflection signal block at the temporal position. The apparatus is configured to attenuate the current diaphragm deflection signal block and to synthesize a modified loudspeaker signal.