A sandwich type of head for application in high-frequency and high-density digital video systems is described. Amorphous CoNbZr films laminated with an AI203insulator layer are used as core material. The influence of rotating and static field annealing on the domain structure and on the permeability is discussed. In order to achieve a sufficiently high efficiency a polycrystalline ferrite back yoke is applied. Sandwich heads with several ceramic materials in the contact plane are evaluated. The performance of the heads is investigated on the basis of a signal-to-noise criterion, defined specially for the digital ‘video application. A sandwich head made with 2x5 Jlm, amorphous CoNbZr, laminated with 0.1 Jlm Ab03, between glass-ceramic substrates fulfils the requirement on MP tape.