A disk drive including a head disk assembly in communication with a printed circuit
board assembly, and further includes a disk drive base and a disk drive cover assembly
collectively housing a head stack assembly and a data storage disk mounted on a
spindle motor assembly for rotating the storage disk. The disk drive cover assembly
further includes first and second substantially-planar rigid members having major
surfaces, a compressible member of a foam composition placed in between the major
surfaces wherein the compressible member is characterized by an unconstrained thickness
d1, and wherein the major surfaces and the compressible member are fixed
in a stacked relationship to compress the compressible member to a thickness less
than d1. The head disk assembly further includes structure for fixing the
disk drive cover assembly to the head stack assembly and the spindle motor assembly.