A magnetic head follows a track in a hard disk drive as positioned by
micro-actuator and voice coil motor. Embodiments operate two control
paths. The micro-actuator control path generates a version of
micro-actuator control signal stimulating the micro-actuator. The voice
coil motor control path generates a version of voice coil control signal,
amplified based upon tuning gain to stimulate voice coil motor. A
decoupling feedback filter decouples these control paths, using the
micro-actuator control signal version. Either control path may include a
notch filter. A track following command, with PES removed, directs the
micro-actuator control. The servo-controller may digitally support the
invention, which may include the servo-controller program system. An
implementation may be optimized within a hard disk drive, possibly as
part of the manufacturing process. The hard disk drive is a product of
that process.