An earplug includes a body, insertable into an ear canal, where the body defines a channel having at least two ends. The channel can house a movable structure configured to allow passage of sound around the movable structure in a rest position, and to block at least a portion of the channel in a deflected position. The movable structure moves from the rest position to the deflected position based on receiving, at one of the at least two ends of the channel, a pressure wave having at least a threshold amplitude pressure to block at least a portion of the pressure wave from reaching the other end of the channel.
