Page7ReferenceManual
TOOLBOX
SETTINGINPUTLEVELS
ReferencePointMicrophone(RPM)
RealTimeAnalyzer(RTA)
WORK
Variable-FrequencySineWaveOscillator(SWO)
YourEars
WCR35WCR35
WCR35
WCR35
Alignmentshouldbecarriedoutwithagoodqualitymicrophone,withaflatresponseatleast
from80Hztoabout15kHz,placedabout5minfrontofthespeakerstackbeingtuned,andata
heightmid-waybetweenthedriverscoveringthetwobandsinquestion.Wewillcallthisthe
ReferencePointMicrophone.WhenusingaRPM,onlyonestackatatimeshouldbetuned.
Thisistrueforbandlevelsetting,timealignmentandsettingcrossoverfrequencies.
TheRPMusuallyneedstobemovedbetweenmeasurements.
DesignedtoworkinconjunctionwithaRPM,thisdeviceoutputsbroadband(pink)noiseinto
thePAviathemixingdesk,andmonitorstheacousticresultviaamultichannelfrequency
analyzer/meter.TheULTRA-CURVEdoesallthisandmore.
Sweepablethroughouttheaudiospectrum,thissinewavegeneratorissimple,inexpensive,
andmaybepluggedintothemixingconsoleviaalineinput.Ifitsoutputlevelvarieswith
frequency,youcouldpatchacompressor/limiterwithslowtimeconstantsandmassiveratio
betweenitandtheconsoletoclampit.YouwillalsoneedaRPM.
Whenauditioningtheoverallsoundofasystem,besuretomoveabouttheauditoriumtocheck
forhotandcoldspots.Thesoundshouldbeoptimizedfortheaveragelisteningposition,
withoutbeingoverlycompromisedelsewhere.Oftenthismeansrunningthesysteminmono.
Atalltimes,havingmadetechnicaladjustmentsusinginstrumentation(SWO,RTA,RPM,
metersandLEDs),useyourearstocheckthattheresultisreasonable.
Thereis+/-12dBcut/boostavailableonbothinputs.
Usually,mixeroutputsensitivityandpoweramplifierinputsensitivitywillbematched:0dB
outputonthedeskwillproduce0dBonapoweramplifier'smeter(ifithasone).Inwhichcase
theshouldbesettohaveaneutraleffectonsystemgain,andallinputand
outputlevelcontrolsshouldreadzero.
Wherethedesk(orDJconsole!)isrunningat-10dBV(semi-prolevel),butthepoweramps
aresetupfor+4dBuoperation,youwillbelookingforthecrossovertoprovideupto14dBof
gain.Trysettingtheinputlevelto+12dBforstarters.
Ifyouarenotsurewhatsensitivityyourconsolehas,trythefollowingprocedure:muteallWCR
35outputs.Drivetheconsolewithaconstantsignal(SWO,RTAorevenmusic)untiltheonset
ofclippingontheconsole'slevelmeters(usuallyindicatedbyaclipLED,orwhenthemetershit
theroof!).adjusttheinputleveltotheuntilitsinputCLIPLEDjustlights.Backoffthe
consoletonormaloperatinglevel(0dB).Nowbothconsoleandhave(roughly)
matchingsensitivities.
Carryouttheaboveprocedurewiththepowerampsturnedoff!
SETTINGBANDLEVELS
RPM,RTA,SWOAgain
WORKBandlevelsshouldoptimallybesetwithaRTA(suchasisfoundintheULTRA-CURVE
programmableanalyzer/equalizerwhichnoself-respectingPAshouldbewithout!)toenable