Tape bias

Tape bias is a high-frequency signal (generally from 40 to 150 kHz) added to the audio signal recorded on an analog tape recorder. Magnetic tape has a nonlinear response at low signal strengths (see coercivity); bias increases the signal quality of most audio recordings significantly compared to unbiased recordings by pushing the signal into the linear zone of the tape's transfer function. As the tape leaves the tape head, the bias partially demagnetizes the tape and the remaining net induction is essentially the difference between the positive and negative half-cycles of the previously recorded. This differencing operation further cancels some of the nonlinearity.

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Early tape recorders simply applied the unadulterated input signal to the record head, resulting in mediocre recordings with poor low-frequency response. In 1940, J. von Braunm?hl and Dr. W. Weber accidentally discovered that the addition of a high-frequency tone kept the recorded signal in the linear response zone, resulting in a striking quality improvement.

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Different levels of bias are needed for different types of tape, so most recorders offer a bias setting switch on the front panel, or, in the case of the compact audio cassette, may switch automatically according to cutouts on the cassette shell.

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KHz: redirect hertz...

Audio: Audio can mean:...

Tape recorder: In general, a tape recorder, tape deck, cassette deck or tape machine is any device that records a fluctuating signal by moving a strip of magnetic tape across a tape head, which is a strong electromagnet. Current flowing in the coils of the electromagnet cause the magnetic material on the tape to a...

Tape bias related Images and Photos (experimental)

Tape	Video Tape	Duct Tape Tie	Duct Tape Mug
Bulls Tape Measurer	Sticky Tape Dispenser	Celtics Tape Measurer	Timberwolves Tape Measurer
Duct Tape Wallet by Ducti	Glee Cassette Tape Mug	Glee Cassette Tape Mug	Smart String Tape Measure