The Type I Normal Bias Audio Cassette

The Type I normal bias audio cassette was the standard and most widely compatible tape format – the direct descendant of the original compact cassette. The tape preserved sound by means of a ferric-oxide coating, and first appeared on the consumer market in the mid 1960s. Heading the post you can see a fairly early Type I musicassette demonstrator, which was used to help drive the cassette format into wider use in 1970.

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.