Editing Cassette deck (section)

==== Dolby HX Pro for higher recording levels on the same tape material ====
[[Bang & Olufsen]] developed the [[HX Pro]] headroom extension system in conjunction with [[Dolby Laboratories]] in 1982. This was used in many higher-end decks. HX Pro reduces the high-frequency bias during recording when the signal being recorded has a high level of high frequency content. Such a signal is self-biasing. Reducing the level of the bias signal permits the desired signal to be recorded at a higher level without saturating the tape, thus increasing [[Headroom (audio signal processing)|headroom]] or maximum recording level.

Some decks incorporated microprocessor programs to adjust tape bias and record level calibration automatically.