An electret microphone assembly in which an insulating support disposed between the apertured front and back walls of a conductive housing has an enclosed portion contained in the housing and an exposed portion extending out of the housing through an opening formed in the side wall thereof. The support carries the back electrode of an electret microphone on the front of the enclosed portion and an FET amplifier circuit on the back of the same portion. Respective electrical contacts formed on the back of the exposed portion of the support extend inwardly through the side opening in the housing to provide external connections to the source and drain of the FET and to the amplifier common line.