The leadoff head in a tape recorder that erases previous recordings from the passing tape by generating a strong and random magnetic field.
"Over the years I had bought several rare LPs, because they were not available on CD and were unlikely to reissued any time soon. Unlike some vinyl aficionados, I don't particularly enjoy handling vinyl records. They're just too fragile compared to my sturdier CDs! As the years went by, I had accumulated an increasingly unwieldy LP collection ..."