Compensation for disk mode disturbances during self-writing of servo
data is provided in a manner that accounts for differences in orientation between
the disk surface from which position information is derived and the disk surface
on which servo data is written. Microactuators corresponding to upper surfaces
of disks may have a wiring polarity that is out of phase with the wiring polarity
of microactuators corresponding to upper surfaces of disks so that disk mode compensation
signals supplied to the microactuators produce motion in opposite directions. The
servo control system may supply signals to microactuators individually and select
the polarities of those signals to account for differences in orientation between
the disk surface from which position information is derived and the disk surface
on which servo data is written.