An apparatus for estimating a property in a borehole penetrating the earth, the apparatus having: a carrier configured to be disposed in the borehole; and an acoustic transducer disposed at the carrier and configured to at least one of transmit and receive an acoustic wave used to estimate the property, the acoustic transducer comprising an acoustic diaphragm; wherein the acoustic diaphragm includes a surface in communication with a plurality of structural members configured to increase the rigidity of the surface, the surface being configured to interface with a medium that propagates the acoustic wave.