Abstract: A modular microphone assembly housed in a handsfree telephone apparatus provides an environment that is isolated from a loudspeaker installed within the apparatus and through which environment the directional and frequency response characteristics of a directional microphone capsule contained within a closable cavity of a microphone mounting receptacle in the assembly are altered via a predetermined internal surface configuration of the receptacle to improve the performance of the apparatus.

Abstract: A holder for an electret microphone of the type having a front acoustic aperture and peripheral acoustic apertures is made of insulating material and includes a first sleeve portion of a diameter to receive the microphone snugly and a second sleeve portion of larger diameter. An internal stop limits the extent to which the microphone can be inserted such that the rear portion of the microphone projects into the second sleeve portion. Through holes in the second sleeve portion provide an acoustic passage to the peripheral acoustic apertures. The internal stop is in one embodiment formed by an apertured web. In another embodiment an internal shoulder forms the stop but in that embodiment too an apertured web is provided. A concentric small cylinder extends from the web in that case and terminates short of the shoulder. In either embodiment, a rectangular plate is molded with the sleeves and this forms the cover of a microphone enclosure.