dbx Discs

How digital dbx disc are made and played.

When the master disc for an album is being cut, the music signal from the digital tape recorder is "dbx encoded". This involves compressing, linearly in decibels, all levels of the audio signal by one-half over the entire frequency spectrum. By doing this, the signal can easily fit within the dynamic range storage capability of the vinyl disc.

The dbx 21 and dbx 222 disc decoder

During playback through an inexpensive decoding unit connected to a stereo system, the signal picked up by the phono cartridge is linearly expanded in a mirror-image fashion so that the dynamic range of the original music signal is completely restored, and in the process, record surface noise is eliminated for all practical purposes.


Lots of discs were available from many record companies. More on SuperDisc/Nautilus.

Last modified: 11-feb-2003