Magnetic recording medium, magnetic recording/reproducing apparatus, and stamper for manufacturing magnetic recording medium

A magnetic recording/reproducing apparatus for reproducing data from a magnetic recording medium which includes a servo area having a preamble area where servo data for clock synchronization is recorded;

• and a data area where user data can be written into via a magnetic head, the magnetic recording/reproducing apparatus comprising:
• an analog-digital converting unit configured to convert an analog preamble reproduction signal into a digital preamble reproduction signal by taking sampled values at six points in one cycle of the analog preamble reproduction signal reproduced from the preamble area at a generation timing of a servo reference clock;
• a phase adjusting unit configured to detect a phase difference of the analog preamble reproduction signal based on the sampled values taken at six points by the analog-digital converting unit, and configured to adjust a phase of the servo reference clock based on the detected phase difference to adjust a sampling timing of the analog-digital converting unit;
• and
• a gain controlling unit configured to detect an amplitude of the analog preamble reproduction signal based on the sampled values taken at six points by the analog-digital converting unit, and configured to control a gain of the analog preamble reproduction signal based on the detected amplitude.