ABSTRACT
Much of the material contained in this chapter could be regarded as historical given the widespread adoption of digital recording and processing, but the justifi cation given at the beginning of the last chapter for its continued inclusion requires that its partnering chapter, also in reduced form, should hold a place in this edition. Noise reduction techniques have been applied to analog tape machines of all formats, radio microphones, radio transmission and reception, land lines, satellite relays, gramophone records and even some digital tape machines. The general principles of operation will be outlined, followed by a discussion of particular well-known examples. Detailed descriptions of some individual systems are referred to in the ‘Further reading’ list at the end of this chapter.
