The Type II Chrome Bias Audio Cassette

A classic blast from the past, in the shape of a mid 1980s BASF CR-E II cassette. A real chromium dioxide formulation, and for many, the epitome of the high bias tape.

The Type II high bias audio cassette is actually much older a development than many people realise. The rise of the Type II tape is generally associated with the 1980s, but in fact, it was introduced, with a chromium dioxide (CrO2) tape formulation, at the dawn of the 1970s.

Chrome tapes were, technically, a big advancement from the start. Du Pont’s chromium dioxide formulation gave an undeniable increase in high frequency response over the often rather muffled tone of the existing Type I ferric cassette. This meant much better definition – a major improvement in fidelity, and an ability to preserve all the zing and sparkle at the treble end of the original sound.

1993 TDK SA-X 60 Super Avilyn Audio Cassette

The early to mid 1990s TDK SA-X 60 audio tape was the upmarket high bias product in the range. TDK had notably used their own Super Avilyn tape coating for high bias Type II cassettes right through the era when chrome was the most popular Type II formulation. But by the time this cassette was manufactured in the early 1990s, most rivals had dropped chrome and followed the TDK path, adopting a cobalt-ferric mix of some sort.

1980s High Bias White Label Audio Cassette

This generic-looking audio cassette, which I acquired in the late 1980s from a local producer of amateur bands, has proved impossible to identify so far.