 Dolby 361 A-type noise reduction module | |
| Product type | Audio technology |
|---|---|
| Owner | Dolby Laboratories |
| Country | United Kingdom United States |
| Introduced | 1965 |
| Related brands | Dolby Stereo (1976-present) Dolby Digital (1986-present) |
| Markets | Worldwide |
| Previous owners | Ray Dolby |
| Website | Dolby official website |
A Dolby noise-reduction system, or Dolby NR, is one of a series of noise reduction systems developed by Dolby Laboratories for use in analog audio tape recording.[1] The first was Dolby A, a professional broadband noise reduction system for recording studios that was first demonstrated in 1965, but the best-known is Dolby B (introduced in 1968), a sliding band system for the consumer market, which helped make high fidelity practical on cassette tapes, which used a relatively noisy tape size and speed. It is common on high-fidelity stereo tape players and recorders to the present day, although Dolby has as of 2016 ceased licensing the technology for new cassette decks. Of the noise reduction systems, Dolby A and Dolby SR were developed for professional use. Dolby B, C, and S were designed for the consumer market. Aside from Dolby HX, all the Dolby variants work by companding: compressing the dynamic range of the sound during recording, and expanding it during playback.