Cassette demagnetizer

A cassette demagnetizer is a device that removes the magnetic field that accumulates during the use of audio cassettes in cassette decks.

The passage of magnetically charged tape over the metallic parts of the tape deck imparts a magnetic polarity that can reduce fidelity in recording and playback. Demagnetizers (also called degaussers) remove this polarity.

Demagnetizers of the cassette type resemble cassettes and contain circuitry to demagnetize tape heads. Demagnetizers of the wand type demagnetize anything that they touch, including tape heads and capstans. The wand's advantage lies in its demagnetizing other metal parts of the tape path, not just the heads. Used carelessly, it can increase the magnetization of the heads; if used too close to tapes, it can erase them. Both of these types of demagnetizer contain electronic circuitry and require a power source (either a battery or a power cord).