A control device includes a control module controlling a polarity switching unit connected electrically to a motor unit of a food processor to provide a first current path for an input power signal through the motor unit when the control module is operated in a processing mode, and further controlling the polarity switching unit to provide a second current path for the input power signal through the motor unit when the control module is operated in a braking mode. A power control unit is connected electrically to the motor unit and the control module, and controls the power control unit such that the power control unit reduces an amount of the input power signal that flows through the second current path during a braking period when the control module is operated in the braking mode.

In a scratch effect control device for a digital audio signal playback apparatus, a control unit controls output of digital audio data recorded in a data recording medium and read by a data reading device in accordance with a first control signal representative of angular velocity and rotational direction of a first encoder disc and obtained from a first pick-up device, and a second control signal representative of angular velocity and rotational direction of a second encoder disc and obtained from a second pick-up device. The first encoder disc is mounted co-rotatably on an outer sleeve sleeved rotatably on an inner spindle and coupled co-axially to a lower platter member that is driven by a driving unit to rotate about an axis. The second encoder disc is mounted co-rotatably on the inner spindle which is coupled co-axially to an upper platter member that is superposed on the lower platter member.