 HX-Pro only applies during recording; the improved signal to noise ratio is available no matter which tape deck the tape is played back on, and therefore HX-Pro is not a noise-reduction system in the same way as Dolby A, B, C & S, although it does help to improve noise reduction encode/decode tracking accuracy by reducing tape performance non-linearity.Some record companies issued HX-Pro pre-recorded cassette tapes during the late 1980s and early 1990s.The widespread proliferation of digital audio in professional and consumer applications (e.g.