CHAPTER 9 |
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INPUT>UNDO MENU
The second stage of Undo is a multi-band expander that is designed to restore dynamic range to audio that has been
excessively compressed.
Each of the five bands of the expander has a corresponding psychoacoustic dynamics detector and a peak detector
that examine the peak levels of the incoming audio, and based upon that information plus the settings of the
various controls, tells the expander how much dynamic range to restore to the audio.
The illustrations that follow show the damaged audio before de-clipping or expansion. The bottom window shows
the same audio after it has been de-clipped and expanded.