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TheInputAGCisthefirstgaincontrolstageinOmnia.9followingUndo,andisdesignedtobeused
as a sloweracting leveler ahead of the Wideband AGC1 and multiband compressor sections that
followit.
Itisworthnotingthattraditionalprocessorsonlyactuponaudioaboveaparticularthreshold.They
aredrivenintovariousamountsofgainreduction,butoncetheaudiofallsbelowthethreshold,they
“runoutof room” or “bottom out,” andareincapable ofincreasingtheaudio any further. They
require some sort of makeup gain control laterin theaudiochain. Thecompressorsin Omnia.9
operateaboveANDbelowthreshold,controllingthedynamicsoveramuchwiderrange.
TheGateThresholdandFreezeThresholdcontrolsworktogethertodeterminethepoints
atwhichthereleaserateoftheInputAGCslowsbyafactorof3(gatethreshold)orfreezes
altogether(freezethreshold).Therangeofthesecontrolsis90dBto0dB.Lowersettings
means the audio must drop to a lower level before the release speed slows or freezes.
Highersettingsmeanstheaudiodoesn’thavetodropasmuchinlevelbeforetheinputAGC
gainslowsdownorstops.
UsinghighersettingswhenemployingfasterInputAGCreleasespeedscankeeptheaudio
frombeingincreasedtooquicklyortoomuchduringquieterpassagesorpauses.
TheRatiocontroldetermineshowmuchtheoutputaudiowillbeincreasedordecreasedin
relationshiptotheinputaudiooftheInputAGCsection.Forexample,aratioof3:1means
forevery3dBofchangeintheleveloftheinputaudio,theoutputwillbechangedby1dB.
Lower (looser) settings provide less control of the dynamics in this section but provide a
more open sound, while higher (tighter) settings provide more control at the expense of
openness.Therangeofthiscontrolis1.0:1toInfinity:1
TheMaximumGaincontrolworksinconjunctionwiththeRatiocontroltodeterminehow
much gain isavailablebelow threshold. Ifthe Input AGC Ratio is setatInfinty:1 and the
InputAGCMaximumGainissetto36dB,theInputAGChas36dBofrangebelowthreshold.
Ataratioof2.0:1andthesameMaximumgainsetting,therangeisreducedbyhalfto18dB.
ThescaletotheleftoftheInputAGCmeterautomaticallyadjustsasneededwhenchanges
aremadetotheInputAGCMaximumGainortheInputAGCRatiotoaccuratelyreflecthow
muchrangeisavailablebelowthreshold.
The Attack control determines the speed with which the Input AGC acts to reduce audio
abovethreshold. Lowersettingsrepresentslower attackspeedsandallowmoreaudioto
pass unprocessed by the Input AGC into subsequent processing stages. Higher settings
result in faster attack speeds and allow less unprocessed audio to enter subsequent
sections. Because all of Omnia.9’s processing stages are to some extent program
dependent,puttingactualmeasures oftime onthesecontrolswould bepointless,and so
the numbers on the various Attack and Release controls throughout are simply relative
numbers.
TheReleasecontroldeterminesthespeedwithwhichtheInputAGCincreasesaudiobelow
threshold. Lower settings provide slower release speeds, while higher settings result in
fasterreleasespeeds.