head but also by the mr type thin film magnetic head 113 in this case the interactive head is disposed along the longitudinal direction with respect to the mr type thin film magnetic head 113 with this structure a single magnetic head can perform not only writing data but also playing it back in this case a magnetic gap of the interactive head is also exposed to the opposing surface of the magnetic head and the center line laterally dividing the interactive head into two parts lies on the center line o u2014 o laterally dividing the magnetic head into two parts also the magnetic head mounted on the rotary head apparatus may be a so called bulk type recording and playback magnetic head having a structure in which a pair of core half bodies composed of high permeability magnetic material such as ferrite are combined so as to face each other along their opposing surfaces opposed to the magnetic tape t and the core half bodies have a magnetic material layer serving as a magnetic gap interposed between the opposing portions thereof in the rotary head apparatus 100 according to the present invention including the rotary drum 100 a having the magnetic heads h 100 a and h 100 b mounted thereon when the magnetic tape t is wound around the rotary head apparatus 100 and is driven to run the magnetic tape t does not slide in the second areas where the displacement of the apex of the convex.