Abstract: An acoustic device may include a housing; an acoustic channel for passing sound through the housing; a valve seat arranged in the acoustic channel; a valve member configured to control the passing of sound through the channel depending on a configuration of the valve member with respect to the valve seat; an actuator comprising a first SMA wire section and a second SMA wire section configured to actuate the valve member and to change a configuration of the valve member with respect to the valve seat from an open configuration to a closed configuration and vice versa, respectively, when activated; and a retention mechanism which is configured to provide a retention force for retaining the valve member in the closed configuration, wherein the retention force is configured to be overcome by the actuator such that the valve member is released from the closed configuration upon activation of the actuator.