An acoustic transducer for generating electrical signals in response to acoustic signals includes a transducer substrate, a back plate, and a diaphragm assembly. The diaphragm assembly includes a first diaphragm and a second diaphragm coupled thereto. The second diaphragm is positioned closer to the back plate than the first diaphragm. The second diaphragm includes a plurality of diaphragm apertures configured to allow air to pass through the second diaphragm. Each of the back plate and the first diaphragm are coupled to the transducer substrate at their periphery. In an embodiment, the transducer includes a post coupled to the first diaphragm and the second diaphragm, the post configured to prevent movement of the second diaphragm relative to the first diaphragm in a direction substantially perpendicular to the second diaphragm.