FIELD: engineering acoustics. SUBSTANCE: underwater adjustable sound-absorbing device has first and second rubber layers which are tightly engageable with each other. Second layer is made of perforated rubber. Introduced in this layer are: third rubber layer bonded on second layer, compressed gas source, pressure gauge, first and second valves interconnected by means of flexible gas line. First layer is made of thin flexible rubber; surface of second layer which is engageable with third layer has system of gas feeding grooves which connect all holes; center-to-center distance of adjacent holes is lesser than or equal to one hundredth of wave length which corresponds to low frequency of preset frequency range of absorption. Compressed gas source is connected with gas feeding grooves through first valve whose outlet is connected with inlets of pressure gauge and second valve. EFFECT: enhanced efficiency. 2 dwg
