A rotary drum assembly for a magnetic recording and playback apparatus includes a rotatable drum (12) provided with rotary heads (14), and upper (16) and lower (18) stationary drums located coaxially with and above and below the rotatable drum (12). A tape (20) is transported wrapping helically around the outer peripheries of the three drums. The upper stationary drum (16) is provided with a generally V-shaped groove (36a) on its outer periphery for guiding the upper edge of the tape and, likewise, the lower stationary drum is provided on its outer periphery with a generally V-shaped groove (38d) for guiding the lower edge of the tape.