Abstract: Methods for testing for defects on magnetic media storage disks are provided. One such method includes dividing a surface of a magnetic media disk into a plurality of radial zones, dividing the disk surface into a plurality of concentric zones, thereby forming a preselected number (N) of wedge subsections for each of the concentric zones, scanning the disk surface for defects, counting the defects contained within each of the wedge subsections, summing the defects contained within two or more of the wedge subsections, comparing the summed defects with a preselected threshold, and determining, based on the comparison, a defect type of the disk.

Abstract: A disk drive is disclosed comprising a disk including a plurality of tracks, a head coupled to an actuator arm actuated over the disk, and control circuitry operable to first seek the head from a first track to a second track, read data from the second track to generate a first read signal, second seek the head from the second track to a third track, read data from the third track to generate a second read signal, third seek the head from the third track to a fourth track, and read data from the fourth track to generate a third read signal. The first, second, and third read signals are evaluated to qualify the disk drive, wherein the first, second, and third seeks are executed in proximity so as to excite the actuator arm with a jitter motion.