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.