Acoustic filter to be inserted in an earplug

摘要

The device has an acoustic system composed of an acoustic inlet (1) and an acoustic outlet (2) separated by an acoustic stack device. The acoustic stack device is composed of a porous membrane, seal joints and metallic protection grid. The acoustic stack device is positioned between the inlet and the outlet. An acoustic resonator (5) is provided in an acoustic outlet, where the resonator is realized by an interior volume of a cylinder part (3).