1930s

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1933

Basing themselves on Pfleumer's experiments, German firms AEG and BASF join forces to develop magnetic tape for sound recording.

Edwin Howard Armstrong patents FM (Frequency Modulation) radio.

Based on the work of Alan Blumlein, the first stereophonic record is produced.

1935

BASF makes the first magnetophonic tapes on a plastic support (cellulose acetate).