Microphone with acoustic attenuation cavity - has underside of diaphragm coupled via orifice and gap to housing cavity

摘要

A microphone is designed with an easily produced resonant cavity to provide the required level of attenuation for satisfactory performance. The main separating wall (1) of the microphone is flanged (2) to provide a location for a location gasket (3) supporting the main diaphragm (4). - The diaphragm carries a thin piezo-ceramic disc (5) coupled to an in-built amplifier (15). The under side of the microphone is encased within a housing (6) around the main separating wall (1). An opening (10) in the all provides an acoustic between the diaphragm underside and the space (9). A plastics disc (11) controls the acoustic coupling via a clearance gap (13) to provide the level of attenuation required.