Omnia Omnia.9 - Input M Enu - U Ndo; What I S U Ndo

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InputMenu–Undo
WhatExactlyIsUndo?
InordertounderstandhowtobestuseUndo,itishelpfultounderstandexactlywhatitisandhowit
works. Undo isactually twoseparateprocesses  adeclipperandamultibandexpander– which
work together to “undo” the poorly mastered, hypercompressed and clipped audio found on so
many modern CD’s.(Note:Thedeclipper works most effectively when using Omnia.9’s digital
inputs.Regardlessofwhetheryouruseananalogordigitalinput,theincomingaudioshouldnotbe
equalizedorpreprocessedinanyway).
Takealookatthetwowaveformsbelow,capturedusingOmnia.9’sbuiltinoscilloscope.The top
windowshowstheunprocessedsourceaudio.Thebottomwindowshowsthesameaudioafterit
haspassedthroughthedeclipper.Noticehowthepeaksthatwereclippedduringmasteringhave
been restored by the declipper.(Note:  The oscilloscope gain was kept at the same level for
comparisonpurposes,butOmnia.9hassufficientinternalheadroom,andthisillustrationsthatfollow
donotsuggestthattheaudioisbeingclippedagainbyanyportionof“Undo”).
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.