Behringer ULTRA-CURVE PRO DSP8024 User manual

Version 1.2 June 2001
User’s Manual
www.behringer.com
ULTRA-CURVE® PRO
DSP8024
ENGLISH

2
ULTRA-CURVEPRODSP8024
Thissymbol,whereveritappears,alerts
you to the presence of uninsulated
dangerous voltage inside the
enclosure—voltage that may be
sufficient to constitute a risk of shock.
This symbol, wherever it appears, alerts
you to important operating and
maintenance instructions in the
accompanying literature. Read the
manual.
SAFETY INSTRUCTIONS
CAUTION: To reduce the risk of electric shock, do not remove
thecover (or back).No user serviceableparts inside;
referservicingto qualified personnel.
WARNING: To reduce the risk of fire or electric shock, do not
expose this appliance to rain or moisture.
DETAILEDSAFETY INSTRUCTIONS:
Allthe safetyand operationinstructions shouldbe readbefore the appliance is operated.
Retaininstructions:
Thesafety and operatinginstructions should beretained for futurereference.
Heed warnings:
Allwarnings on the appliance andin theoperating instructions should be adheredto.
Followinstructions:
Alloperation anduser instructionsshould be followed.
Water and moisture:
Theapplianceshould not beusednearwater(e.g. nearabathtub,washbowl,kitchen sink, laundrytub,ina wet
basement, or near a swimming pool etc.).
Ventilation:
Theapplianceshould besituatedsothat its locationorposition does notinterferewith its properventilaton.For
example, the appliance should not be situated on a bed, sofa rug, or similar surface that may block the
ventilation openings: or placed in a built-in installation, such as a bookcase or cabinet that may impede the
flowofair throughtheventilation openings.
Heat:
The appliance should be situated away from heat sources such as radiators, heat registers, stoves, or other
appliances(including amplifiers) thatproduce heat.
Power source:
Theappliance shouldbe connectedto a powersupply onlyof thetype describedin the operatinginstructions
or as marked on the appliance.
Grounding or polarization:
Precautionsshould be taken so thatthe groundingor polarizationmeans of an appliance isnot defeated.
Power-cord protection:
Power supply cords should be routed so that they are not likely to be walked on or pinched by items placed
upon or against them, paying particular attention to cords and plugs, convenience receptacles and the point
wherethey exitfrom theappliance.
Cleaning:
Theappliance shouldbecleaned onlyas recommended bythe manufacturer.
Non-useperiods:
Thepowercordof the applianceshouldbeunpluggedfrom the outletwhenleftunusedfor a longperiodoftime.
Object and liquid entry:
Careshould be takensothat objectsdonot fall andliquidsare notspilledinto the enclosurethroughopenings.
Damage requiring service:
Theapplianceshould beservicedby qualified servicepersonnelwhen:
- the power supply cord or the plug has been damaged; or
- objects have fallen, or liquid has been spilled into the appliance; or
- the appliance has been exposed to rain; or
-the appliancedoes notappear tooperate normallyor exhibits a marked changein performance;or
-the appliancehasbeen dropped,or theenclosuredamaged.
Servicing:
Theusershouldnotattempttoservicetheappliancebeyondthatwhichisdescribedintheoperatinginstructions.
Allother servicing shouldbereferred toqualifiedservice personnel.

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ULTRA-CURVEPRODSP8024
FOREWORD
DearCustomer,
welcometo theteamof ULTRA-CURVE PROusersand thankyou very muchfor expressing yourconfidence
in BEHRINGER products by purchasing this unit.
It is one of my most pleasant tasks to write this letter to you, because it is the culmination of many months of
hard work delivered by our engineering team to reach a very ambitious goal: making an outstanding device
betterstill. TheULTRA-CURVE hasfor quite along timebeen astandard tool usedby numerousstudios and
PA rental companies. The task to improve one of our best-selling products certainly meant a great deal of
responsibility,which weassumed byfocusing on you, the discerninguser andmusician. Italso meanta lot of
work and night shifts to accomplish this goal. But it was fun, too. Developing a product usually brings a lot of
peopletogether, and whatagreat feelingitis wheneverybodywho participatedinsuch aprojectcan be proud
ofwhatwe’veachieved.
Itisour philosophytoshare our joywithyou, because youarethe mostimportantmemberof theBEHRINGER
family. With your highly competent suggestions for new products you’ve greatly contributed to shaping our
companyand making itsuccessful.In return,weguarantee you uncompromisingquality (manufactured under
ISO9000 certified management system) as well as excellent technical and audio properties at an extremely
favorable price. All of this will enable you to fully unfold your creativity without being hampered by budget
constraints.
Weareoftenaskedhow we canmanageittoproducesuch high-grade devicesatsuchunbelievablylowprices.
The answer is quite simple: it’s you, our customers! Many satisfied customers means large sales volumes
enablingus to get better conditionsof purchasefor components, etc. Isn’t itonly fairto passthis benefit back
to you? Because we know that your success is our success, too!
Iwouldliketothankallpeoplewhose help on “Project ULTRA-CURVE PRO” has made it all possible.Everybody
hasmadevery personal contributions,startingfrom the designersoftheunit viathemanystaff membersinour
company to you, the user of BEHRINGER products.
Myfriends, it'sbeen worththe trouble!
Thankyou very much,
UliBehringer

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ULTRA-CURVEPRODSP8024
DSP8024
ULTRA-CURVEPRO
Ultra-high performa ce digital stereo mai frame powered by two 24-bit high-speed digital sig al processors
sHigh-endAKM and CRYSTAL24-bitAD/DA convertersforultra-high dynamicrangeand resolution
sOpen-ended&“future-proof”architecture allows forfuturesoftwareupgrades
sUltra-musicaldual 31-band graphicequalizer with “truefrequency response”characteristics
sLow/high/bellshelving tool withvariable slope(3- 30dB)
sRealtime analyzerwithpeak hold,variableintegration, cursorread-out and 10user-memories
sAutomaticroom equalizationusingmicrophone inputandinternal noisegenerator
sAdditional6 bandsof fully parametricequalizer/notch filterwith upto 1/60th octavebandwidth
sIntegral fully automatic feedback destroyer with intelligent signal analyzer for ultra-fast feedback
suppression
sIntegraldigital “brickwall” limiter protectsagainst anyclipping anddangerous sound pressurelevels
sIntegraldigitalnoise gatewithBEHRINGER’s unique IRC(InteractiveRatio Control)
sIntegral delay with up to 2.5 seconds delay time selectable in milliseconds, meter and feet
sUltra-accuratelevelpeak meterwithpeakhold andselectablereference levels (+4dBu/-10dBV/DIG MAX)
sFullMIDI parameterandsnapshot controlforrealtime editing
sFreeEQ-Design software allowsfortotal remotecontrolvia PC (downloadat www.behringer.com)
s100user memories canbe storedunder any alphabetic name. Memorybacked bya long-life battery
sSecuritykey passwordcanbe installedforuser selectiveRTA and EQmemory protectionandunattended
use
sEQ and analyzer curves may be copied, compared, added or subtracted for extreme flexibility
sCrossfade feature to fade between two settings and stereo link facility to synchronize both channels
s24-bit AES/EBU interface for digital inputs and outputs at 32, 44.1 and 48 kHz (optional)
sLargehigh-resolution LCDgraphicdisplay withhigh-contrastLED backlight
sServo-balancedinputs andoutputson gold-platedXLR and 1/4" TRSconnectors forhighsignal integrity
sRelay-controlledhard-bypasswith anauto-bypassfunction during powerfailure(failsafe relay)
sHigh-qualitycomponents andexceptionallyrugged constructionensure long lifeand durability
sInternalpower supply designforprofessional applications
sManufacturedunderISO9000 cerfified managementsystem

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ULTRA-CURVEPRODSP8024
TABLE OF CONTENTS
1. INTRODUCTION.....................................................................................................................6
1.1 The designconcept......................................................................................................................... 6
1.2 Beforeyoubegin ............................................................................................................................. 6
1.3 Controlelements............................................................................................................................. 7
2. OPERATION............................................................................................................................8
2.1 EQ mode ........................................................................................................................................ 9
2.1.1 Operatingthegraphic equalizer............................................................................................. 9
2.1.2 Thelevelmeter...................................................................................................................... 9
2.1.3 TheFEEDBACKDESTROYER........................................................................................... 10
2.1.4 Delay ...................................................................................................................................11
2.1.5 Equalizer editing ..................................................................................................................11
2.1.6 EQ setup ............................................................................................................................ 13
2.2 Realtime analyzer ........................................................................................................................ 14
2.2.1 Program administration ....................................................................................................... 15
2.2.2 Toolbox ............................................................................................................................... 15
2.2.3 Choosing asource .............................................................................................................. 15
2.2.4 Decay ................................................................................................................................. 15
2.2.5 RTAsetup........................................................................................................................... 16
2.3 AUTO-Qfunction........................................................................................................................... 17
2.4 Generalsetup ............................................................................................................................... 18
3. APPLICATIONS .....................................................................................................................20
3.1 Using the ULTRA-CURVE PRO as a summing EQ in a PA ........................................................... 20
3.2 Using the ULTRA-CURVE PRO for monitor EQ purposes ............................................................. 22
3.3 Usingthe ULTRA-CURVE PROin therecording studio ................................................................ 23
3.4 The ULTRA-CURVE PROas adelayunit ...................................................................................... 23
4. “TRUE RESPONSE” CHARACTERISTIC ..........................................................................25
5. ULTRA-CURVE PRO structure ...........................................................................................26
5.1 Hardware....................................................................................................................................... 26
5.2 EQ mode ...................................................................................................................................... 27
5.3 RTAmode ..................................................................................................................................... 28
6. INSTALLATION .....................................................................................................................29
6.1 Mains connection.......................................................................................................................... 29
6.2 Audioconnections ........................................................................................................................ 29
6.3 Digitalaudio connectionsper AES/EBU(optional) ........................................................................ 30
6.4 MIDIconnections .......................................................................................................................... 31
7. APPENDIX .............................................................................................................................31
7.1 AES8024 option............................................................................................................................ 31
7.2 Changingthe memoryprotect battery ........................................................................................... 31
7.3 MIDIimplementation ..................................................................................................................... 32
7.4 Software........................................................................................................................................ 33
8. TECHNICAL SPECIFICATIONS ...........................................................................................34
9. WARRANTY ...........................................................................................................................36

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ULTRA-CURVEPRODSP8024
1. INTRODUCTION
TheBEHRINGER ULTRA-CURVE PROis afully digitalsound processingdevice based on DSPs and 24-bit
A/DandD/A converters. Thehigh-speedDSPsare capable ofperforminganyprocess in fractionsofasecond,
theonlyelementgoverning their performancebeing thesoftware.Theenormousflexibilityavailable meansthat
the ULTRA-CURVE PRO has a range of features greatly exceeding those found in a conventional analog
graphicequalizer—ata pricepreviouslyunimaginable.
The BEHRINGER ULTRA-CURVE PRO has two channels which can be used independently or coupled via
software.
+The following operational manual will introduce you to the ULTRA-CURVE PRO and its various
functions.After reading the manual carefully, makesureitis always on hand for futurereference.
1.1 The design concept
The philosophy behind BEHRINGER products guarantees a no-compromise circuit design and employs the
bestchoiceofcomponents.Top-quality24-bitAD/DAconverterswhichbelongtothebestcomponents available
owing to its outstanding specifications and excellent sonic characteristics. Two 24-bit DSPs are used as the
heart of the ULTRA-CURVE PRO. These perform the precise calculations needed for the processing of the
complex algorithms. Additionally, the ULTRA-CURVE PRO uses high quality resistors and capacitors with
very tight tolerances, high-grade switches, ultra low-noise operational amplifiers as well other selected
components.
The ULTRA-CURVE PRO DSP8024 uses SMD technology (Surface Mounted Device). These subminiature
componentsknown fromaerospacetechnology allowforan extremepacking density, plusthe unit's reliability
couldbeimproved.Additionally,theunitis manufactured in compliancewith theISO9000 certifiedmanagement
system.
Fail-safe relays have been incorporated into the design of the BEHRINGER ULTRA-CURVE PRO, which
automatically and silently bypass the unit in the event of power supply disconnection or failure. These relays
arealsoactiveatswitch-ontoisolatetheULTRA-CURVE PROuntilthepowerrailshavesettled,thuspreventing
the possibility of a potentially damaging switch-on thump.
1.2 Before you begin
YourBEHRINGERULTRA-CURVE PRO was carefullypackedin the factoryandthepackaging was designed
toprotecttheunit from roughhandling.Nevertheless,werecommend that youcarefully examinethepackaging
and its contents for any signs of physical damage, which may have occurred in transit.
+If the unit is damaged, please do not return it to us, but notify your dealer and the shipping
company immediately, otherwise claims for damage or replacement may not be granted.
Shipping claims must be made by the consignee.
The BEHRINGER ULTRA-CURVE PRO fits into two standard 19" rack unit of space (2 U). Please allow at
least an additional 4" depth for the connectors on the back panel.
Besurethatthereisenoughspacearoundtheunitforcoolingandpleasedonotplace the ULTRA-CURVE PRO
onhigh temperature devicessuch as poweramplifiers etc.toavoid overheating.
+Before you connect your ULTRA-CURVE PRO to the mains, please make sure that your local
voltage matches the voltage required by the unit!
The mains connection of the ULTRA-CURVE PRO is made by using a mains cable and a standard IEC
receptacle.It meetsall ofthe internationalsafety certificationrequirements.
+Please make sure that all units have a proper ground connection. For your own safety, never
remove or disable the ground conductor of the unit or of the AC power cable.
Asstandard,the BEHRINGERULTRA-CURVEPROis installedwithelectronically servo-balanced inputsand
outputs.Thecircuitdesignfeaturesautomatichumrejectionforbalancedsignals,permittingtrouble-freeoperation
even at the highest operating levels. Externally induced power-line hum, etc. is thus suppressed effectively.
1. INTRODUCTION

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ULTRA-CURVEPRODSP8024
Theautomaticservofunction recognizesthe presenceofunbalancedconnectors and adjuststhenominallevel
internallyto avoidleveldifferences betweenthe input andoutput signals(6 dBcorrection).
The optional digital input and output (AES/EBU interface) connections are balanced with a negative ground.
High-qualityconnectors ensure isolated,noise-freesignal throughput.TheMIDI connections(IN/OUT/THRU)
havebeen realized withstandardized DINplug-inconnectors. Optocouplershavebeen usedforisolated data
communications.
1.3 Control elements
Fig. 1.1: The control surface of the ULTRA-CURVE PRO
1
The heart of the front panel is the LED backlighted 240 x 64 active DISPLAY. The control of the
ULTRA-CURVE PROincenteredaroundthecentraldisplay.Theuserinterfaceisforalargepartgraphical,
complemented by four text based setup menus. The function of the softkeys is displayed right next to
thesekeys, theirfunction changesto accommodate differentfeatures.
2
To the right of the display you will find the MIDI LED which registers incoming MIDI messages.
3
TheEQ keyswitches the ULTRA-CURVE PROintoequalizer mode.Inthis mode, theEQ,FEEDBACK
DESTROYER,LIMITER andDELAYfunctions maybeused.
4
The RTA key switches the ULTRA-CURVE PRO into analyzer mode. This mode is solely concerned
withmeasuring andsignal generation, thesound willnot be affected!
5
IN/OUTkey. TheULTRA-CURVE PROcan beswitchedinto thesignalpath (LED isgreen) or switched
out(bypass,LED dark).TheLEDflickering red indicatesDSPoverflow. This doesnotnecessarily mean
“clipping”. Flickering starts as soon as an internal overflow in one of the filters occurs, while input and
output levels may be o.k. When this LED lights up often, reduce the input level or the
ULTRA-CURVE PRO’sgainlevel.
6
The SETUPkey allowsentry intothe setup menuswhere allthe basicadjustments ofthe device are to
befound, suchasthe choiceofinput source,sample rate, passwordprotection, MIDIconfigurationetc.
Pressingoncewill open eithertheEQsetup or RTAsetup,dependingon the functionoftheunit. Holding
thekey downfortwo secondsor more willopen thegeneral setup windowsconsisting ofa global setup
andaMIDI setupwindow.Pressingthe setupkeyhere will togglebetweenboth general setupwindows.
7
Tothe leftof thedisplay four SOFTKEYS,labelledA, B,Cand Drespectively,are tobefound arranged
vertically. Their functions can be defined by the user software and displayed to the immediate right of
each key by the appropriate pictogram in the display. Each pictogram and its associated functions will
becomprehensively explainedinchapter 2.Youwill findfunction diagrams forboth EQ andRTA mode
as well as a list of all pictograms used on an extra sheet.
8
To the right of the display the CURSOR KEYS are to be found. These are used:
1.to selectindividual filter frequencies,and themaster fader inequalizer mode(horizontal)
2.to adjustthe value ofeach selectedfrequency (vertical)
3.to positionthe measurementcursor inanalyzer mode(horizontal)
4.in bothoperating modes,to choose the program position(vertical)
5. to select a field in the SETUP menu (horizontal and vertical)
1. INTRODUCTION

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ULTRA-CURVEPRODSP8024
+In each case pressing on the opposite key while holding the key being used will accelerate
the operation being carried out.
Fig.1.2: The rearpanel layout of the ULTRA-CURVE PRO
9
This is the MAINS CONNECTOR/FUSE HOLDER/VOLTAGE SELECTOR. Before you connect the
unit,please makesure thatthe displayedvoltage corresponds to your mains supply. Please note that,
dependingon themainsvoltage suppliedto the unit,the correctfusetype andrate must beinstalled. In
someunits, thefuse holdercan beinserted in twopositions toswitch between220 to240 Vand 100 to
120 V. Please note that a higher fuse rating must be used when operating the unit outside of Europe
with115V (seechapter6 “INSTALLATION”).
10
Please use the enclosed mains cable to connect the unit to the mains power supply.
11
TheMAINS SWITCHis tobefound abovethe mainssocket. The switchis situatedon the rearpanel to
maketheULTRA-CURVE PROtamperproofwith unattendeduse.Theunit willbypassonpower failure
but cannot be bypassed when a password is set.
12
SERIALNUMBER.Pleasetakethetimetohavethewarrantycard filledoutcompletelybyyourspecialized
dealer, and return it within 14 days after the date of purchase, so as to be entitled to benefit from our
extended warranty. You may also use our online registration option available on the Internet at
www.behringer.com.
13
AES/EBUINand AES/EBUOUT.ThesearetheULTRA-CURVE PRO’sdigitalinputandoutput(optional).
The analog output signal is also present at the (analog) outputs when the digital out is used. Both
signals can be used in parallel.
14
These are the ULTRA-CURVE PRO’s MIDI connectors (MIDI IN/OUT/THRU). Via these connectors
total remote control is possible.
15
ANALOGOUTPUTS. These arethe ULTRA-CURVE PRO’sanalogoutputs. When theAES/EBUoption
isinstalled the analogoutputwill stillbepresent attheseoutputs, sothatboth analoganddigital out can
beused inparallel.
16
Thesearethe ULTRA-CURVE PRO’sANALOGINPUTS.
17
Thisis theMIC INPUTsocket forthe referencemicrophone.
2. OPERATION
TheBEHRINGERULTRA-CURVE PRO isaflexible,universallyapplicablesoundprocessingandmeasurement
device,whoseoperationsmay bedividedintotwobasic areas; signalprocessor(equalizer,limiter) or realTime
analyzer (RTA). For this reason, you always operate in either EQ or RTA mode. Simultaneous operation of
both is not possible!
Uponswitching on theULTRA-CURVE PROyou willbepresented eitherthemain equalizer (EQ),or analyzer
(RTA)window. By pressingtheEQ orRTAkey, theULTRA-CURVE PROwill switch fromRTA- into EQ mode
and vice versa. When the ULTRA-CURVE PRO is switched from one mode to the other, the outputs will be
brieflymuted.
2. OPERATION

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ULTRA-CURVEPRODSP8024
2.1 EQ mode
Fig.2.1: Main EQwindow of theULTRA-CURVE PRO
Thedisplayshowsa31-bandgraphicequalizer,alongwiththemainfaderforoveralllevelcontrol—slightlyseparated
on the right hand side. On the left are the pictograms for the softkeys, which are used to open the sub-menus.
2.1.1 Operating the graphic equalizer
The selected controller is illustrated highlighted in the display. The vertical cursor keys are used to adjust
levels,thehorizontalkeystoselect the controllerto beadjusted. Whenyou depressa cursorkey, aninformation
window appears showing the selected frequency, the level of boost or attenuation applied to each of the two
channels,as wellas the programnumber andprogram name:
Fig.2.2: Graphic EQinformation window
Theinformation windowdisappearsafter fourseconds if no furtherkey hasbeen pressed.
Depressinga keyoncewill resultina parameterchangingby thesmallest applicable increment.The adjacent
faderwill beselected, ora level willbe adjustedby 0.5 dB.Depressing andholding the cursorkey resultsin a
continuous change in the parameter. The rate of change remains constant. You can increase the rate of
changeby first depressingand holding thekey used tochange the relevantparameter, and then—stillholding
the first key—depress the one opposite.
2.1.2 The level meter
By pressing softkey A you leave the main EQ window and access the menu to display levels.
Fig. 2.3: LEVEL METER display
Youcan use the level meterto controlthe input and output levelsof theULTRA-CURVE PRO. The bargraph
displaycontrols theeffective RMSlevel (massiveparts ofthe bars),and the peak level (checkered tips ofthe
bars),both simultaneously.To save youreyes, therelease time ofthe peakdisplay is 20 dB/s.The maximum
levelsare memorized andnumerically displayed.
2. OPERATION

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ULTRA-CURVEPRODSP8024
Whenthe limiter thresholdisexceeded, theindicationLIM willappearin the levelmeterdisplay toindicatethat
the limiter is attenuating the output.
With softkey A you leave the level meter, and return to the main EQ window.
With softkey B you erase the maximum levels from the memory.
With softkey C /you switch the display from the ULTRA-CURVE PRO input and output.
Withkey Dyoucanchoosebetweenthreedifferenttablesofreferencelevels.The0dBpointisindicatedbyabold
marker,whileatthesametime,thenumericaldisplaychanges. referstothedigitalpeaklevel.Thislevelmay
not—underanycircumstances—beexceeded!Thiswillresultinaverynoticeableformofdistortion,whichoccurs
muchfaster,andsoundsvery much moreunpleasant,thanthefamiliardistortion associated with analogdevices.
refers to the operating level found in professional audio equipment (analog inputs and outputs of the
ULTRA-CURVE PRO). referstotheoperatinglevelfoundinhomerecordinganddomesticaudioequipment,a
typicalexamplebeingtaperecorderswithRCAconnectors.WhensettingtheULTRA-CURVE PROinternallevel,
orwhenusing the optionalAES/EBUinterface,thepeakleveldisplayoftheDIG MAXscaleistheonly onetouse.
The+4dBu and-10dBVscalesservetomonitortheanaloginputsand outputsoftheULTRA-CURVE PRO.
Please note that the RMS level will usually be quoted in the technical specifications of analog devices for
example,for theinputsensitivity ofpower amplifiers.Theeffective levelalways lies belowthe peaklevel.
+The difference between them depends on the signal characteristics for a static sine wave, the
effective level is about 3 dB below the peak level. For a dynamic signal the difference is in the
region of 8 dB.
TheDIG MAXlevel is, ofcourse, relatedto theanaloginput andoutput levels,as 0 dBDIG MAXcorresponds
tothemaximum output level oftheULTRA-CURVE PRO.Thefollowingexample,usingasinewaveatmaximum
amplitude,clearly illustratesthe relationshipbetween thevarious scales:
RMS PEAK
DIGMAX -3 dB 0 dB
+4 dBu +6 dB +12 dB
-10 dBV +21 dB +24 dB
Maximum level:
Reading
Scale
+16 dBu
Tab. 2.1: Level meter scale correlation
Ascanbeseenfromtheabovetable,theULTRA-CURVE PROsmaximumanalogoutputlevelis+16dBu,or+14dBV.
TheULTRA-CURVE PROs analog inputscanhandle signalsofup to+21dBu, but itisimportant toremember
that,incaseof such high input levels,thedigitallimitermayoperateifthelevelintheequalizerisnotappropriately
lowered. Please refer to the operation of the digital limiter explained in section 2.1.6.
2.1.3 TheFEEDBACK DESTROYER
Bypressing softkeyB you leavethe main EQwindow andgo intothe FEEDBACK DESTROYERmenu.
Fig. 2.4: FEEDBACK DESTROYER menu
Thedisplaywillshowthe current settingsforallsixofthe ULTRA-CURVE PRO parametricequalizers(selected
frequency,bandwidthand degreeofboostor attenuation).Additionallyit will showwhetherthe parameters are
fixed(PAR), or aresetfor automaticsearch,to functionasthe FEEDBACKDESTROYER(AUT or SGL).Auto
2. OPERATION