PURPOSE: To prevent the generation of head wear and to obtain a stable head output.

CONSTITUTION: Notches 23, 24 existing in the succeeding part of the rotating direction of a drum in both side parts in the axial line direction of the drum of a magnetic head 21 are formed. A negative pressure is, therefore, generated in the region within these notches 23, 24 among the regions of the air film formed between the rotary drum and a magnetic tape T at the time of high- speed rotation of the drum and the magnetic tape T is drawn toward the surface of the rotating drum and, therefore, the magnetic tape T is brought into sure pressure contact with the magnetic head 21 by relatively low tape tension. Since the thickness of the air film is settable at approximately a specified size near the magnetic head 21, approximately the same pressure contact state is obtd. in the arbitrary position of tape winding and, therefore, the contact of the magnetic head 21 and the magnetic tape T is uniformalized.