Abstract: A tone generator of the type in which a housing defines a pair of communicating chambers one of which is closed except for an area of communication with the other chamber. A thin flat diaphragm of circular configuration is mounted in an operative position over the area of communication between the chambers in engagement with a flat annular surface defining the same. An annular diaphragm retaining member is mounted in an operative position in superposed relation to the diaphragm in fixedly secured relation within the housing. An improved mounting for the diaphragm is provided which includes a plurality of annularly spaced transversely extending diaphragm engaging lugs formed on the retaining member. The lugs extend in engagement with the diaphragm so that when the retaining member is in its operative position the engagement of the lugs with the diaphragm serves to retain the diaphragm in its operative position.