A magnetic signal on the tape resulting from the finite size and non-uniform distribution of magnetic particles in the magnetic layer of the tape.
Tape noise is inherent in any magnetic tape but can be reduced by using smaller pigment sizes in tape formulations. The iron oxide pigments found in less expensive tapes have the largest tape noise level.
Pigment size ranking in tapes is: iron oxide ->chromium dioxide ->metal particulate ->barium ferrite.
Therefore, tape noise ranking, from loudest is: iron oxide ->chromium dioxide ->metal particulate ->barium ferrite.