Abstract: An acoustic system and method of fabricating the acoustic system, wherein the acoustic system comprises at least one tube having at least one opening through which an acoustic wave travels to increase sensitivity of the acoustic system and at least one hydrophone in the at least one tube, wherein the at least one hydrophone is encapsulated and the method comprises inserting at least one encapsulated hydrophone in at least one tube with at least one opening through which an acoustic wave travels to increase sensitivity of the at least one hydrophone, inserting the at least one tube into a fluid, and receiving the acoustic wave through the fluid by the at least one hydrophone.

Abstract: Methods and apparatus for providing a sound suppressor device including a first plate, a second plate in opposition to the first plate, and a connector between the first and second plates such that the first plate, the second plate, and the connector define a sealed cavity containing a gas at a pressure, wherein the device has a resonant frequency selected to vibrate out-of-phase with respect to a noise source for suppressing noise from the noise source while the noise source and the device are immersed in a liquid.