Text: Feedback is a term indicating that a signal is being returned to some earlier point in the amplification chain. In some cases, the return of the signal is intentional and has salutary results. In negative feedback, for instance, part of an amplifier's output signal is applied to an earlier stage in negative (i.e., opposite) phase to the signal normally at that point in the circuit. Negative-feedback circuits reduce distortion, extend frequency response, and are essential to the electronics of high fidelity. Unwanted feedback, however, can be quite pesky.

See Also: ACOUSTIC FEEDBACK

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