Disk drive and servo-control method therefor

A disk drive, comprising:

• a head for accessing a disk;
• an actuator configured to support said head and to move said head by action of a voice-coil motor in a substantially radial direction of said disk by rotation about a pivot shaft;
• and
• a controller configured to perform servo control of said actuator by using servo data read out by said head, said controller comprising at least one of a plurality of notch filters having a fixed center frequency inserted in a servo-control loop;
• wherein said controller is configured to increase an attenuation rate by at least one of said plurality of notch filters having said fixed center frequency at a designated frequency, when a target position of said head is at a position selected from the group consisting of a position outside of a specified region and a position within said specified region, and wherein said controller is configured to increase said attenuation rate before a seek starts to said target position, when said target position is within said specified region.