The armature of an electromagnetic transducer, extending through the polarizing flux between opposing permanent magnet pole faces, is snubbed to limit its shock-induced excursions normal to the directions of its extent and of the flux field. Such snubbing helps to protect the armature from plastic damage and accompanying shift of magnetic balance of the transducer upon the occurrence of a strong mechanical shock in an arbitrary direction.

A hearing aid microphone module housing all the electronic components needed for a functional hearing aid other than the battery and receiver is described which uses flip-chip technology to couple a JFET buffer to the components. The buffer is disposed on a PCB which defines a back volume of the housing.

A disposable-type hearing aid uses a relatively large single diaphragm or a large single diaphragm subdivided into a plurality of smaller active diaphragm areas obtained using a grate-like back support plate with ridges which contact and divide the diaphragm into the several smaller active diaphragm areas. The diaphragm and a backplate are enclosed in a metal housing and are disposed proximal and parallel to a shell-like hearing aid enclosure having sound inlets. The metal housing is closed at an end opposite the sound inlets by a printed circuit board (PCB) forming an acoustical seal for a back volume of the microphone. The PCB also carries substantially all the electronic components for the hearing aid thereon. The PCB has a ground plane in contact with the housing whereby the PCB also acts as an EMI shield. An electrical connection is formed in various ways between the back support plate and the PCB during assembly of the metal housing and components with the PCB. Mass production of disposable hearing aids with large diaphragms and relatively low noise levels is thus possible using this invention.

A balanced receiver providing significantly reduced vibration is disclosed. The balanced receiver comprises a closed loop operably attached between an armature and a diaphragm. The effective moving mass of the diaphragm is designed to match the effective moving mass of the armature. The closed loop facilitates the balancing of the motion of the diaphragm and the motion of the armature, thus reducing the vibration of the receiver.

A receiver assembly includes a first diaphragm assembly having a diaphragm, and a second diaphragm assembly having a diaphragm. A linkage assembly is coupled to an armature of the receiver. The linkage assembly is also coupled to the first diaphragm assembly and to the second diaphragm assembly.