Manual

“D-Max”ClipLimiter

Themainlimitationwithtraditionaldynamicscontrolistheinabilityoftheprocessingtoreacttruly

instantaneouslytothesignal.Oneofthemostsignificantadvantagesofdigitalsignalprocessingover

analogueistheabilitytodelaytheaudiosignalpreciselyandwithoutextensivecomplexhardware.Theentire

domainofdigitalsignalprocessingisbasedaroundthecombinationofdelaying,multiplying,andaccumulating

numbers(representingsamplesofaudio)toimplementallthefiltersanddynamicsprocessingwehavecome

toexpecttoday.

Inthecaseofdynamicsprocessing,beingabletodelayasignalallowstheprocessormoduletodelaythe

mainsignalinrelationtothesidechain(thesignalbeingmonitoredrelativetothethreshold),sothatitcan

compensateforpeakspriortothearrivalofthemainsignal.

Considerthesituationofamonitorengineerlisteningtoabandperform.Havingnoaccesstodynamics

processors,hehashadtoresorttomanually'ridingthefaders'inanattempttokeepcontrolofthelevels.

Shouldthelevelofoneofthechannelsonhisdeskreachanunacceptablyhighlevel,hewillturnitdown

appropriately.

Thereisahiddensidechaininoperation

eveninthiscase.Themainsignalpathis

fedthroughthemonitordeskandthegain

controlledbyadjustingthefader.The

sidechainisformedbythefeedbackpath

betweentheengineer'searscheckingthe

levelandhisbraininstructinghishandto

turnthefaderdownifthevolumegoesover

thethresholdhehaschosen.

Inthiscase,thedelaybetweenthesignalactuallygoingoverthethreshold,theengineerregisteringthe

situation,andthenturningthesignaldownwillbeintheorderofseveralhundredmillisecondsatbest.This

willonlybetrueifheisnotdistracted–inreality,itmaybeseveralsecondsbeforeanygainreductionis

imposedonthesignaltobringitundercontrol.

Forananaloguedynamicsprocessor,thesituation

ismuchbetter.Controllingthegainelectronically,

andnotrelyingonahumansidechainfeedback

mechanism,itcanreactmuchmorequickly.

Theredwaveformrepresentstheinputtothe

dynamicsmodule,withthedottedlineshowingthe

thresholdforgaincontroltooccur.Thereare

severalpeakstowardsthestartofthissignalthat

areabovethethreshold,andsothedynamics

processingshouldreacttotheseasappropriate.(In

thiscasereducethegain).

Thebluewaveformshowstheoutputofthe

dynamicsmodule.Thecircledpeakdemonstrates

thattheprocessorhasmissedthefirstpeakabove

thethreshold(asitisveryfastandshort),buthas

'caughtup'shortlyafterwards,keepingallother

peaksundercontrol.Asitisunabletopredictwhat

iscoming,thiswillalwaysbeafailingwithanalogue

dynamicsprocessing.