To provide a disk drive capable of inhibiting the occurrence of acoustic noise caused by a voltage pulse when the head is retracted using a speed control method using voltage obtained by rectifying a back electromotive force after the power source has been cut off from the rotation of a spindle motor. Retraction control circuit is used to control the on and off modes of transistors in accordance with the speed of VCM. The voltage across VCM becomes a voltage that can be regulated with VCM voltage control circuit. At this time, voltage is supplied to the terminals based on the voltage of ISO5V that is the rectified voltage of the back electromotive force of the spindle motor and the pulsating voltage is synchronized and produced at both terminals. As a result, the potential difference across VCM is such that the pulsating voltage is negated and acoustic noise is inhibited.