Abstract: A transducer, capable of converting noise signals to electrical voltage signals, is mounted in contact with a movable member and the electrical voltage output thereof is converted to a current function which then is converted to a DC signal which is directly proportional to the noise generated from the movable member. This DC signal then is compared with a generated, predetermined control signal that represents the desired motion at which an event can take place, such as the shifting of a vehicle transmission between forward and reverse conditions. When the DC signal matches the control signal the event can occur, either automatically or by manual manipulation.