A cassette demagnetizer is a device that removes the
magnetic
Magnetism is the class of physical attributes that are mediated by a magnetic field, which refers to the capacity to induce attractive and repulsive phenomena in other entities. Electric currents and the magnetic moments of elementary particl ...
field that accumulates during the use of
audio cassettes
The Compact Cassette or Musicassette (MC), also commonly called the tape cassette, cassette tape, audio cassette, or simply tape or cassette, is an analog magnetic tape recording format for audio recording and playback. Invented by Lou Otten ...
in
cassette deck
A cassette deck is a type of tape machine for playing and recording audio cassettes that does not have a built-in power amplifier or speakers, and serves primarily as a transport. It can be a part of an automotive entertainment system, a part of ...
s.
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
An electronic circuit is composed of individual electronic components, such as resistors, transistors, capacitors, inductors and diodes, connected by conductive wires or traces through which electric current can flow. It is a type of electrical ...
to demagnetize
tape head
A tape head is a type of transducer used in tape recorders to convert electrical signals to magnetic fluctuations and vice versa. They can also be used to read credit/debit/gift cards because the strip of magnetic tape on the back of a credit card ...
s.
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.
The types of demagnetizer described above contain electronic circuitry and require a power source (either a
battery
Battery most often refers to:
* Electric battery, a device that provides electrical power
* Battery (crime), a crime involving unlawful physical contact
Battery may also refer to:
Energy source
*Automotive battery, a device to provide power t ...
or a power cord). A third design consists of a cassette shell with a head cleaning tape wound on the spools and a magnetic disc mounted above the head cleaner tape. When the deck "plays" the cassette, the tape cleans the heads and simultaneously the magnet rotates, creating the alternating magnetic field required for demagnetizing.
Some cassette decks demagnetizes themselves. These work by feeding the record head a high-frequency signal, whose amplitude is great at first and then is reduced to zero over a few seconds.
{{DEFAULTSORT:Cassette Demagnetizer
Audio storage