A waterproof speaker module may include a membrane formed from at least one waterproof and elastic material and a supporting structure. The membrane may include an outer surface, an inner surface, and at least one concave region that is indented toward the inner surface. The supporting structure may be coupled to the membrane and include a support structure that mates with the concave region of the membrane when the speaker is subjected to a hydrostatic load. When the speaker is not subjected to a hydrostatic load, the support structure may contact the concave region. In this way, the membrane may be resistant to tearing or rupture due to hydrostatic load.