Abstract: A microphone comprises a substrate (20), a microphone membrane (10) defining an acoustic input surface and a backplate (11) supported with respect to the membrane with a fixed spacing between the backplate (11) and the membrane (10). A microphone periphery area comprises parallel corrugations (24) in the membrane (10) and backplate (11). By using the same corrugated suspension for both the membrane and the backplate, the sensitivity to body noise is optimally suppressed.

Abstract: A speaker comprises a permanent magnet (2) and a coil (8) positioned around the permanent magnet (2) and attached to a membrane (10), wherein the membrane comprises an elastomer of thickness less than 0.3 mm and with a Young's modulus below 100 MPa.

Abstract: A MEMS transducer (10) for an audio device comprises a substrate (12), a membrane (14) attached to the substrate (12), and a back-electrode (18) attached to the substrate (12), wherein a resonant frequency of the back-electrode (18) is matched to a resonant frequency of the membrane (14). Further, a method of manufacturing a MEMS transducer (19) for an audio device comprises attaching a membrane to a substrate (12), attaching a back-electrode (18) to the substrate (12), matching a resonant frequency of the back-electrode (18) to a resonant frequency of the membrane (14).

Abstract: A microphone comprises a movable diaphragm 2 and a back electrode 4. The mechanical relationship between the back electrode 4 and the diaphragm 2 is adjustable thereby to control the cut-off frequency of the microphone. This enables the microphone to be adapted to different noise environments.

Abstract: A membrane (2) for a microphone (1) is disclosed which comprises a first portion (A1), a second portion (A2), and elements (E1 . . . E4, E1? . . . E4?), which connect said first (A1) and said second portion (A2). The second portion (A2) is arranged for a movement in relation to said first portion (A1) around an idle position, which movement includes at least a translatory component in a direction of movement (dm) normal to said membrane (2). The elements (E1 . . . E4, E1? . . . E4?) are provided for definition of a spring constant for said movement around said idle position and are arranged substantially along the outer border of said second portion (A2).