Abstract: The present document describes a method and apparatus to rapidly reticulate closed-cell or partially closed-cell foams. The method involves the propagation of an energy impulse inside the foam; the energy impulse can be a shock wave. The energy impulse is generated in the same gaseous environment in which the foam is immersed, preferentially air in room condition. The energy impulse destroys the membranes closing the foam cells without disintegrating the frame's structure. In particular, the method rapidly improves the acoustic and filtering behavior of the foams.