JBL 5233 Manuale

ProfessionalSeries

Installationand

ServiceManual

ElectronicFrequency

DividingNetworks

5233SingleChannel

5234DualChannel

OWNER'S

INSTRUCTIONS

WARNING—

Topreventfireorshockhazard,donotexposethisapplianceto

rainormoisture.

JBLcontinuallyengagesinresearchrelatedtoproductimprovement.

Newmaterials,productionmethodsanddesignrefinementsareintro-

ducedintoexistingproductswithoutnoticeasa routineexpressionof

thatphilosophy.Forthisreason,anycurrentJBLproductmaydifferin

somerespectfromitspublisheddescriptionbutwillalwaysequalor

exceedtheoriginaldesignspecificationsunlessotherwisestated.

Specifications

Gain0 dBinthepassband

RatedOutput6.2V (+18dBref.0.775V)

DistortionLessthan0.5%THD,20-20,000Hz

atratedoutput

Lessthan0.2%THD,20-20,000Hz

at+10dBref.0.775V

FrequencyResponse±0.5dB,20-20,000Hz

CrossoverFrequencySelectablebyplug-inmodule,

3dBcrossoverpoint±10%

FilterSlope12dBor18dBperoctave

InputImpedance-.Greaterthan50kfl

LoadImpedance600O orgreater

OutputImpedance47fi

ChannelIsolationGreaterthan60dB,20-20,000Hz

Signal/NoiseRatioGreaterthan90dB,20-20,000Hz

equivalentbandwidth

ControlsHighFrequencyLevel(eachchannel)

SupplyVoltageSelect

PowerRequirement5 W 120/240V AC,50/60Hz

OperatingTemperatureUpto55°C(132°F)

Dimensions44mmx 483mmx 194mmdeep

x 19x 7%indeep

:Mounting1 EIAstandardrackspace

PanelFinishSemi-glossnon-glarebakedenamel,

darkgray

NetWeight1.8kg(4lb)eitherunitwith

accessorycrossovercard(s)installed.

ShippingWeight3.0kg(6.5lb)eitherunit

:Accessories

CrossoverCards51-5130BlankCard,Unloaded18dB/Octave

I(onerequired51-5132500Hz18dB/Octave

perchannel)51-5133800Hz18dB/Octave

52-5120BlankCard,Unloaded12dB/Octave

52-5140For4343and4350StudioMonitors

Owner'sInstructions

The5233and5234aredesignedforusewithstudio

monitororsoundreinforcementloudspeakersystemswhere

bi-amplificationortri-amplificationisdesirable.The5233

[singlechannel]and5234(dualchannel)featuredifferential

highimpedanceinputs,unitygaininthepassband,and

unbalancedlowimpedanceoutputs.The5233willprovidea

singlechannelcrossover.The5234providestwoseparate

channelswithindependentcrossoveraction(asina stereo

installation).

Thepowerswitchandpilotlightfortheunitanda high

frequencylevelcontrolforeachchannelarelocatedonthe

frontpanelforeasyaccess.Thecrossoverfrequencyat

whicheachchannelisoperatingisindicatedthrougha front

panelwindow.A voltagechangeswitchislocatedontherear

panel.

EithermodelcanbemountedinoneEIAstandard

rackspace.

Crossovercardsareavailableformostcommonlyused

frequencies.Filterslopesare12dBor18dBperoctave

withhighandlowfrequencyoutputattenuated3 dBatthe

crossoverpoint.Cardsarealsoavailablewiththespecific

crossovercharacteristicsrequiredfortheJBL4343or4350

bi-amplifiedstudiomonitors.Inaddition,blankcardscanbe

obtainedforconstructionofcrossovernetworksforother

frequencies.

Installation

Theelectronicfrequencydividingnetworkreceivesthe

programsignalfroma linelevelsource-preamplifier,studio

console,orportablemixer-andseparatesthesignalinto

highandlowfrequencybands.Outputsfromthenetwork

feedtheappropriatepoweramplifiers,whichinturndrive

theirrespectiveloudspeakersystemcomponents.Input

connectionsmaybebalancedorunbalanced,output

con-

nectionsareunbalanced;shieldedcableisrequired.Ifoutput

cablelengthsaregreaterthan4.5to6 m (15to20ft),isolation

transformers(600ft: 600ft) arerecommendedateach

outputtoreducethepossibilityofradiofrequencyinterference

orhum.Theoutputscandeliver+18dB(6.2V into600ft)

andwilldrivethelineinputsofconventionalamplifiers.Two

ormorepoweramplifierscanbedrivenfromeachoutput.

The5234dualchannelnetworkcanbeusedtotri-amplify

aloudspeakersystembyconnectingthelowfrequency

outputofchannel2 totheinputofchannel1.(Twisttwo

unshieldedwirestogetheroruseshieldedcableforthis

connection.)Thechannel

outputscanthenbeusedtodrive

themidrangeandlowfrequencyamplifiers.Typicalinstal-

lationsarediagrammedinFigure1.

Whenevera midrangeorhighfrequencydriverisconnected

directlytoa poweramplifier,a seriescapacitorisrecom-

mendedtoattenuateunwantedlowfrequency"on-off"

switchingtransientsignalswhichcandamagethedriver.

Itispossibletoconstructa systemusinganelectroniclow

frequencytransitionanda conventionalpassivenetworkfor

themidrangeorhighfrequencycrossover.TheJBL4350

StudioMonitor,diagrammedinFigure2,issucha system.Ifa

pairof4350saretobeused,a single5234canaccommodate

bothsystems.Notethatthepassive,highlevelfrequency

dividingnetworksusedinallJ BLstudiomonitorsdesignedfor

bi-amplificationalreadyincorporatetherequiredattenuation

capacitorstoprotectthemidrangeandhighfrequency

drivers.

ConventionalPassiveNetworks

PROGRAM

SOURCE

ONE

AMPLIFIER

LOUDSPEAKERSYSTEM

PASSIVE

FREQUENCY

DIVIDING

NETWORK

LOUDSPEAKERSYSTEM

PROGRAM

SOURCE

ONE

AMPLIFIER PASSIVE

FREQUENCY

DIVIDING

NETWORKS

Two-WaySystem Three-WaySystem

ElectronicNetworks

PROGRAM

SOURCE LOUDSPEAKERSYSTEM

— 1

ACTIVE

FREQUENCY

DIVIDING

NETWORK

PROGRAM

SOURCE

ACTIVE

FREQUENCY

DIVIDING

NETWORK

HIGH

Two-WaySystemwithSingleChannelActiveCrossover Three-WaySystemwithDualChannelActiveCrossover

PROGRAM

SOURCE

PROGRAM

SOURCE

LOUDSPEAKERSYSTEM

Fig

re1.

Typical

Installations of the

5233

and

5234

Compared

to Conventional

Passive

Networks

HIGH

LOW

HIGH

MID

LOW

TWO

AMPLIFIERS

5233

HIGH

LOW

5234

THREE

AMPLIFIERS

LOUDSPEAKER

SYSTEM

LOW

FOUR

AMPLIFIERS

LOUDSPEAKERSYSTEM

CHANNEL

5234

CHANNEL

LOW

HIGH

LOW

ACTIVE

FREQUENCY

DIVIDING

NETWORK

TwoIndependentTwo-WaySystemswithDualChannelActiveCrossover

LOUDSPEAKERSYSTEM

ACTIVE

FREQUENCY

DIVIDING

NETWORK

Figure

Combining

Electronic

and

Passive

Frequency

Dividing Networks

Mounting

The5233

5234can

mounted

ina

single

EIA

standardrackspacewithoutadditionalbracing

ventilation.

Allexternalconnectionsaremadeontherearpanel.Mounting

hardware

suppliedwitheachunit.

Connections

Shieldedcable

necessary

for

allinputandoutput

connections.Makecertainthattheshield

properly

con-

nected,

shown

Figures

and

Input connections-Inputs

the5233and5234are

fora

linelevelsource,balanced

unbalanced.Screwterminals

the

rearpanel

are

provided

for

connection

eachinput

andareclearlyidentified.Balancedconnectionsareshown

incolorexchanging

and

conductorswillresult

inphasereversal.

AMPLIFIER

PROGRAM

SOURCE

5233

PROGRAM

SOURCE

JAMPLIFIER

LOUDSPEAKER

SYSTEM

DualChannel

5234

ELECTRONIC

FREQUENCY

DIVIDING

NETWORK

AMPLIFIER

LOUDSPEAKER

SYSTEM

CHANNEL

LOUDSPEAKER

SYSTEM

CHANNEL

Figure

Wiring Diagram

for

Bi-Amplification

PROGRAM

SOURCE

TWO

AMPLIFIERS

5233

ULTRA-HIGH

HIGH

MID

PASSIVEFREQUENCY

DIVIDINGNETWORK

5233

ELECTRONIC

FREQUENCY

DIVIDING

NETWORK

SingleChannel

HIGH

LOW

AMPLIFIER

HIGH

LOW

HIGH

LOW

PROGRAM

SOURCE

CHANNEL1

PROGRAM

SOURCE

PROGRAM

SOURCE

CHANNEL

5234

ELECTRONICFREQUENCYDIVIDINGNETWORK

5234

PROGRAMSOURCE

(UNBALANCED)

PROGRAMSOURCE

(BALANCED)

Output

Connections

-Eachoutputchannelcandeliver

6.2V into600Q orgreater(+

dBref.0.775V}.A separate

pairofscrewterminals,locatedontherearpanel,isprovided

forthelowandhighfrequencyoutputofeachchannel.

Outputswilldrivethelineinputofanyconventionalamplifier.

Typically,theimpedanceofa bridginginputisatleast5 kn

(usually10knormore);thereforetwoormorepower

amplifierscanbedrivenbya singleelectronicfrequency

dividingnetwork.

Operation

VerificationofSystemWiring

Itisimperativethateachoutputoftheelectronic

frequencydividingnetworkbeproperlyconnected.

Inadvertentexchangeoflowandhighfrequencyoutput

connections—atthenetwork,poweramplifiers,ortrans-

ducers—mayresultinseveredamagetomidrangeorhigh

frequencyloudspeakersystemcomponents.

Thefollowingprocedureshouldbefollowedforeach

programchannelpriortooperation.

Withallpoweroff,settheHighFrequencyLevelcontrol

at"2"andadjusttheprogramsourceleveltominimum

(Thesourcematerialmaybewidebandnoiseormusic.)If

thepoweramplifiersareequippedwithlevelcontrols,adjust

themtoapproximatelyonequarterpower.

Turnontheprogramsource,network,andamplifiersfor

thechannelundertest.

3.Graduallyincreasetheprogramsourcevolumeleveluntil

audible.Ifthesoundcomesmainlyfromthemid-rangeor

highfrequencydriver,shutpoweroffimmediatelyand

AMPLIFIER

checkallwiring.Ifthelowfrequencyloudspeakerproduces

bass,

graduallyadvancetheHighFrequencyLevelcontrol.

Correctsystemwiringwillbeverifiedifthetreblecompo-

nentoftheprogrammaterialincreasesinlevelwhile

comingsimultaneouslyfromthemidrangeandhigh

frequencydrivers.

TransducerPhasing

Oneimportantfactorinthenaturalsoundcharacter

ofa loudspeakersystemisthephaserelationshipofthe

transducersforanoctavebelowandaboveeachcrossover

frequency.Twosuitablemethodsforestablishingproper

phaseofthecomponentsina two-waysystemaredescribed

inthefollowingparagraphs.Eitheronemaybeused,depend-

ingontheavailabilityoftestequipment.A three-orfour-way

systemshouldbetreatedina similarmannerbyfirstestab-

lishingtheproperphaseforthetransducersofthelow

frequencytransitionandthenprogressingtothemidrange,

highfrequency,orultra-highfrequencytransducers,as

applicable.

Objective

Method-A realtimethirdoctaveanalyzer,

condensermicrophone,anda pinknoisesourcecanbe

usedtoestablishproperphaseoftheloudspeakersystem

componentsasfollows:

Usingpinknoiseasprogrammaterial,adjustsystem

volumeforcomfortablelisteningandsetthelevelsofthe

individualtransducerstodisplayflattestoverallfrequency

responseontherealtimeanalyzer.

Reversepolarityofthehighfrequencydriverandobserve

theeffectonfrequencyresponsethroughthecrossover

region.

Properphasingofthetransducersisindicatedby

theflattestfrequencyresponsethroughthecrossover

regionasshownontherealtimeanalyzer.

AMPLIFIER LOUDSPEAKERSYSTEM

HIGH

MID

LOW

Figure4.Wiring Diagram forTri-Amplification

Shieldedcableisnecessaryforallinputandoutputconnec-

tions,

asshown.Makecertainthattheshieldisproperly

connectedtothegroundterminal.

Subjective

Method— Iftestinstrumentationisnotavailable,

properresultscanbeobtainedasfollows:

Adjustvolumelevelforcomfortablelisteningandset

approximatesystembalanceusingpinknoiseorthenoise

heardbetweenstationsofanFMtuner.

Listentoa recordingofa malevoicelongenoughto

becomeaccustomedtotheperformanceofthe

loud-

speakersystem.

3.Reversepolarityofthehighfrequencyloudspeaker,which

willproducea changeinvoicecharacter.Whenthetrans-

ducersareproperlyphased,a recordedmalevoiceshould

soundnaturalandexhibitpresence[oran"upfront"

quality],

incontrasttotheundesirable"hollow"sound

heardwhentransducersareoutofphase.

Note:

Ifthecrossoverfrequencyliesabove2 kHz,reversing

polarityofthehighfrequencycomponentwillcreatelittle

(ifany)perceptibledifferenceinsystemperformance.The

"correct"polarityinsucha casewillbethatwhichyields

themostnaturalqualitywitha varietyofprogrammaterial.

Onceproperphaseamongthetransducersofa

loud-

speakersystemhasbeendetermined,otherloudspeaker

systemsintheinstallation(assumingtheyarethesame

model]maybephasedaccordingly.Ifdifferentloudspeaker

systemsareused,establishcommonphaseamongthelow

frequencydriversandfollowtheaboveproceduresfor

eachsystem.

LovolControlAdjustment

Inmostinstances,manufacturersofmulti-amplified

loudspeakersystemsprovideinstructionsforbalancinglevels

oftheindividualdriversofthesystem.Intheabsenceof

formalinstructions,orinthecaseofcustomloudspeaker

systems,balancecanbeestablishedbyadjustinglevelsto

achievetheflattestresponseona realtimeanalyzer,as

describedabove,oronthebasisofsubjectiveevaluationof

familiarprogrammaterial(or,moreaccurately,byusingpink

noiseorthenoisebetweenFMstations]asdescribedinthe

followingparagraphs.

Eachprogramchannelshouldbeadjustedindividually;

subjectiveevaluationshouldbemadewhileseatedinthe

normallisteninglocation.Ifsubjectiveanalysisistobeused,

andthepoweramplifiersareequippedwithlevelcontrols,

initiallyadjustthecontrolstoonehalfoftheirfullrotation

andthenregulateasnecessary.

Subjective

Adjustment of Bi-Amplified

Systems—The

followingappliestoa 5233ortoeachchannelofa 5234used

indualchannelbi-amplification.

(

Rotatethenetworkcontrolclockwiseuntila satisfactory

highfrequencybalancehasbeenobtainedintheprogram

material.

Ifnecessary,trimsourceoramplifierlevels.

Subjective

Adjustment of Tri-Amplified

Systems-When

bothchannelsofa 5234areusedfora tri-amplified

loud-

speakersystem,itisgenerallyinstalledsothattheChannel1

levelcontrolregulatestheoutputofthemidrangedriver

andtheChannel2 levelcontrolgovernsonlythehigh

frequencydriver.

WithbothHighFrequencyLevelcontrolsat"0','adjustthe

sourcelevelforcomfortablelistening.

RotatetheChannel1 levelcontrolclockwiseuntila

satisfactorymidrangelevelhasbeenobtainedinthepro-

grammaterial.Ifnecessary,adjustsourceoramplifierlevels

asappropriate.

3.IncreasetheChannel2 leveluntila satisfactoryhigh

frequencybalancehasbeenobtained.Itmaybenecessary

toreadjustmidrange,source,oramplifierlevelstoachieve

themostdesirableoverallbalanceoftheloudspeaker

system.

Oncehighfrequencyandamplifieroutputlevels

havebeenestablished,readjustmentisnotgenerally

needed.

Somemethodofmarkingorlockingthepower

amplifierlevelcontrolsisrecommended.

WiththeHighFrequencyLevelcontrolat"0"adjustprogram

sourcelevelforcomfortablelistening.

ServiceInstructions

Thedividingnetworksareshippedwitha 52-5120cross-

overcardwithtwo1000ohmresistorsinstalledineach

channel,

asinFigure5.Thiscardconvertseachchannelinto

aone-input,two-outputunitygaindistributionamplifier.Two

ofthesespeciallyloadedcardswillconvertthe5234totwo

independentdirectamplifiers,eachhavingoneinputandtwo

outputs,orthenetworkinputscanbeparalleledtoprovide

fouroutputsfroma singlesource.The"highfrequency"

channelwillbeatunitygainwhenthelevelcontrolissetat

maximum.Thecontrolcanbeturneddowniflossisdesired.

The52-5120crossovercardmustberemovedbefore

installingthefrequencyselectioncardneededforthepartic-

ularapplication.Toinstalla newcrossovercard

Placethe5233or5234upsidedownona softsurface,

removethetwoPhillips-headscrewsfromeithersideofthe

case,

andliftthebottomcoverfromthechassis.

Removetheoldcrossovercardbyliftinggently.

3.Alignthethreeholesineachnewcrossovercardwiththe

correspondingmountingpinsonthemainprintedcircuit

board.

Thecomponentsonthecardshouldfacetoward

thechassiswiththefrequencydesignationlabeltoward

thefrontpanel.

Asthecardisgentlypressedagainstthemountingpin

stops(roughly6 mm,

in),electricalconnectionwillbe

madebetweenthecardconnectorandsixpinsonthe

printedcircuitboard.

5.Replacethebottomcoverandsecureitwiththefour

screws.Theunitisnowreadyformountingandconnection

ofthevariousinputsandoutputs.

NOTE:

Operationofthe5233or5234withouta crossover

cardwillnotdamagetheunit.

WARNING:

Thissectionofthemanualcontainsserviceinstructionsfor

usebyqualifiedservicepersonnelonly.

VoltageConversion

The5233and5234canbeoperatedfromeithera 100-120

VACor200-240V AC,50/60Hzsource.TheSUPPLY

VOLTAGESELECTswitch,S301,convertstheunitfromone

operatingvoltagerangetotheother.Usethefollowingpro-

cedurestoconvertthepreamplifiertoa differentvoltagerange.

Disconnecttheunitfromthepowersource.

SlidetheSUPPLYVOLTAGESELECTswitchtotheappro-

priatelinevoltagerange.

3.Changethelinecordandattachmentplugtomatchthe

powersourcereceptacleorusea 120-to-240V adapter

(notprovided).Theattachmentplugand/orlinecord

usedfor240V ACmodeintheU.S.andCanada

isU.L.listedandOS.A.Certified.Foruseinothercountries

linecordselectionshouldbebasedonlocalregulations

governing240V AC50/60Hzsupplysource.

Table1.

VoltageWiringCode

SwitchS301 SwitchS201

Ground,

Terminal1 Terminal1 E401

U.S.A.

Black White Green

Europe Blue Brown Green/Yellow

CAUTION:

Thisunitmaybedamagedifoperatedwiththesupply

voltageselectswitchsetincorrectlyforthelinevoltageapplied.

BlankCrossoverCardAssembly

Inadditiontothestandardcrossovercards,circuitsfor

othercrossoverfrequenciesmaybeassembledonblank

crossovercardsusingstandardcomponents.Filterslopes

(12or18dBperoctave)areidenticaltothoseofthestan-

dardcrossovercards.Thecrossoverfrequencycanbewritten

onthecardbracketandwillappearthroughthefrontpanel

windowofthenetwork.

The

crossover

card

pressed

on to mounting

pins

shown

Note the use of two

hands

maintain

proper

alignment for

installation or removal of the card. Figure5.Direct Amplifier Modification

Using

two I /en,Vz W, 10%

resistors

on a 52-5120 blank

crossover

card

shown,

and installing the card,

will

convert

crossover

channel

to a

unity

gain amplifier having one

input

and

two outputs.

Table2.

12dB/Octave

BlankCrossoverCard

ComponentValues

Resistorsareall% W,5%tolerance.Capacitorsareall5%

tolerance,metalizedpolyester.

WARNING:Thissectionofthemanualcontainsserviceinstructionsfor

usebyqualifiedservicepersonnelonly.

Crossover

Frequency

(Hz)

Capacitors

C1-C5'

(MF)

Resistors

R1-R5'

(kn)

50 .22 10

70 .22 7.5

100 .22 4.7

200 .12 4.7

300 .082 4.7

400 .055 5.1

600 .039 4.7

700 .032 5.1

900 .027 4.7

1100 .022 4.7

1500 .012 6.2

2000 .012 4.7

2500 .0082 5.6

3000 .0068 5.6

3500 .0068 4.7

4000 .0056 5.1

4500 .0039 6.2

5500 .0033 6.2

6000 .0033 5.6

6500 .0033 5.1

7500 .0027 5.6

8000 .0027 5.1

8500 .0012 11

9000 .0022 5.6

9500 .0012 10

10000 .0022 5.1

Thecomponentvaluesforothercrossoverfrequenciescanbecalcu-

latedusingtheformulaRC=whereR istheresistanceinkn,

CisthecapacitanceinnF.andF isthefrequencyinHzTherec-

ommendedminimumvalueforR is4.7kO.

Figure6.12

dB/Octave

Blank

Crossover

Card

(JBL

Model

52-5120)

Component

values

for the

various

frequencies

are

listed

Table

Components

should

rest

against the printed circuit

board.

Leads

should

soldered

and cut

flush.

Table3.

18dB/Octave

BlankCrossoverCard

ComponentValues

Resistorsareall% W,5%tolerance.Capacitorsareall5%

tolerance,metalizedpolyester.

CrossoverFrequency Capacitors Resistors

30Hz CV-N/A RV-N/A

(HighPass

Only]

C2'-N/A R2'-N/A

C3'-N/A R3'-N/A

C4'-.33uF R4'-11kn

C5'-.33nF R5'-4.3kn

C6'-.33MF R6'-75kn

250Hz C1'-.015MF

'-5.6kn

C2'-.39MF R2'-5.6kn

C3'-.022^F R3'-5.6kn

C4'-.039MF R4'-12kn

C5'-.039nF R5'-4.7kn

C6'-.039uF R6'-82kn

500Hz SameasJBLCrossoverCard51-5132.

SeeTable5.forvalues.

800Hz SameasJBLCrossoverCard51-5133.

SeeTable5.forvalues.

1200Hz C1'-.039MF R1'-4.7kn

C2'-.10

R2'-4.7kn

C3'-.0056

R3'-4.7kn

C4'-.0082MF R4'-12kn

C5'-.0082MF R5'-4.7kn

C6'-.0082MF R6'-82kn

5500Hz C1'-.0068MF R1'-5.6kn

C2'-.018uF R2'-5.6kn

C3'-.001JJF R3'-5.6kn

C4'-.0018MF R4'-12kn

C5'-.0018mF R5'-4.7kn

C6'-.0018 fjF R6'-82kn

8000Hz C1'-.0056uF

'-4.7kn

C2'-.015iiF R2'-4.7kn

C3'-820pF R3'-4.7kn

C4'-.0012uF R4'-12kn

C5'-.0012MF R5'-4.7kn

C6'-.0012,iF R6'-82kn

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