Interference effects between planar and normal components of magnetization in an isotropic tape are used to separate the contribution of each and address the question of transition lengths for so‐called vertical recording. For low level record signals (−4 dB relative to optimum band edge current) and high coercivity isotropic or anisotropic media, the dominant magnetization at short wavelength is found to be normal to the plane (vertical), and the transition length is nonexistent. The isotropic medium supports twice the normal component of the anisotropic medium. Constructive interference of the two components causes apparent departure from the Wallace equations although each component is exactly described by the Wallace model. Increasing current causes a log/linear attenuation which may be caused by factors other than transition length. Using the isotropic tape, densities of 10 000 transitions/mm (250 000 f.c.i.) are seen.