A speaker system having a structure in which the room surrounding the
first diaphragm and the room adjacent to the second diaphragm are
acoustically coupled. The second diaphragm has coating on a surface.
Applying the coating to the second diaphragm enhances the reliability and
performance of the speaker system. Besides, the diversely definable
geometry of the diaphragm allows an electronic device employing the
speaker system or the speaker module to have flexibility in design.