Halcro DM38 User manual

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TableofContents
Important SafetyInstructions....................................................................2
Introduction.....................................................................................................3
Installation.......................................................................................................4
Unpacking.................................................................................................4
Positioning................................................................................................5
Connections.....................................................................................................5
Connecting the MainsSupply Cable...................................................5
Connecting the Loudspeakers..............................................................5
Connecting the ExternalGround.........................................................6
Bridging.....................................................................................................6
Running-inperiod...................................................................................6
dm38InputSelections............................................................................6
Commentsonthedifferentdm38inputs...........................................7
Operating Instructions.................................................................................8
ElectronicProtectionand Reliability........................................................9
Specificationsforthedm38.......................................................................13
CareandMaintenance................................................................................14
Troubleshooting...........................................................................................15
Service.............................................................................................................16
Warranty.........................................................................................................17
Warranty RegistrationForm.....................................................................18

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ImportantSafety Instructions
120lb
CAUTION
RISKOFELECTRICSHOCK
DO NOT OPEN .
Thisproduct shallbeconnectedtoaMAINS socketoutletwith a
protectiveearthingconnection.
Weighs55kg(120 lbs.)perunit.Shipping weight-85kg (187lbs.).
Neverlifttheamplifierbyyourself.
Alwaysuse twopeople tounpack ormovetheamplifier.Always
bendatthekneeswhenlifting.Donotstrainyour back.
Designedforindooruseonly,thedmrangeof amplifiersarenot
protectedagainstliquids.Theyshouldnotbe exposedtodripping
orsplashingandnoobjectsfilledwith liquids,suchasvases,
shouldbeplacedonthem.
Thedm38isproducedintwomodelsdesignedtooperateon
differentmainpowersupplies.
110Vmodel(Halcroitem411-005):100 -120V,45-65Hz
240Vmodel(Halcroitem411-006):220-240V,45-65Hz
TheAmplifier’sPositiveLoudspeakerTerminal cangenerate
HazardousLiveVoltages.To complywith International Safety
StandardsonlyuseLoudspeakercableswith wellinsulated
terminalssuchasWBT-0660.Alwaysswitchtheamplifiersto
StandByorOFF beforetouchingtheseterminalsoradjusting
loudspeakerconnections.
Neverobstruct the airflowtotheheatsinks.
Containsnouserserviceableparts.Donotattempt toopenanyof
theamplifiercompartments,asthismayexposeyoutodangerous
voltagesandwill voidthe warranty.
Allcompartmentsare sealedatthefactory. Ifthesealsarebroken,
thewarranty will bevoidandallservicecostswill bechargedto
the owner.
RequiresF10AL250Vfuse (if operatingon220–240V)or
F15AL110Vfuse(ifoperatingon100–120V)forcontinued
protectionagainsttheriskoffire. Neverbypassoruseany other
typeof fuse. Thefuseislocatedonthebottomof theamplifier,
nearthe masterON/OFF switch.
Warning do notuse any cableslongerthan3M

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Introduction
Congratulationsonpurchasingthe HALCRO™dm38 Stereoamplifier.
HALCRO™designsandmanufacturesthe only "SuperFidelity"
amplifiersinthe world.This"Super Fidelity"amplifier reproduceswith
better than 99.9997%purity ofalltonesacrosstheentireaudiorange.
Theconceptbehindtheelectronicdesignwastocreatean amplifier,
whichdidnotcolorthesoundwithitsownelectroniccharacteristics.
i.e.recreatethe originalsoundasitwasatthetimeof recording.
Pleaseenjoy theHALCRO™audioexperience.
HALCRO™hasenjoyedcreatingperfectaudioreproductionforthe
world'smusicconnoisseurs.
IfyoudesiretocontactHALCRO™togiveusfeedbackonyour
purchaseor for generalenquiries;
pleasefeelfreeto:
email [e-mail]
orphone [phone]
orfax+61882380852

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Installation
Ensureyou have readtheImportantSafetyInstructionssectiononpage2,priorto
installing your HALCRO™amplifier.
Ifyou requireassistanceinthe unpackingandinstallationofyourHALCRO™
amplifier,pleasecontactyour dealer.
PLEASENOTE:
Whenlifting theunit, alwaysusetwo people.
Theunitmustbeliftedbyplacingyourhandsunderthemiddleofthebottom
compartment.Do not lifttheunitunderthetopcompartment.
Unpacking
1.Unscrewthe4knurledknobsatthebaseofeachbox. Thenremovethe upperpart
ofthe containerby lifting directly upwards, tillitclearsthetop oftheamplifier.
2.Withanassistant,removetheplasticwrappingandfoampieces,thenliftthe
amplifierfromthebaseofthe container.Removetheplasticcoveringfromthe unit.
Pleasesaveitfor later use.
3.Movetheunittoitsfinallocation(see Positioning).Whitecottongloveshavebeen
providedtopreventmarkingtheamplifierwhilemoving itintoplace.
Important
• Donotconnectany cablesasyet.
• Safely storethe packagingso itmaybeusedforfuturerelocationofthe unit,and
for shippingif serviceisrequired.

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Positioning
Wesuggestthatthedm38bepositionedasnear toyourloudspeakersaspractical.This
will reducethelengthofthe loudspeakercablerequired.Thesidesofthe unithouse
theheatsinksthatareusedtodissipateheat.The airflowtotheseshouldnotbe
interrupted. Ensurethereisatleast12 inches(300mm) clearancearoundtheunit.
Connections
ConnectingtheMainsSupply Cable
Plugthemainsplugintotheunit'ssocket,whichispositioned, attherear, onthe base
of the bottomcompartment,whichhousesthepowersupply.Ensurethe cableexitsto
therear of the unit. Do notplug into themainsoutlet.
ConnectingtheLoudspeakers
The dm38has4loudspeakerterminals:
• 2x Positive+(RedBezel).
• 2x Negative-(BlackBezel).
Allofthe pure copperconnectionsarefinishedwiththehighest-gradegoldplating.
• Ensurethepositiveterminalofthe amplifierconnectstothepositiveterminalof
theloudspeaker. Thiswill ensurecorrectphasingoftheaudiosignal.
• The loudspeakerterminalswillacceptspadeorhookterminals.Only fully
insulatedterminal aretobeused.
• Ensuretheloudspeaker terminalsaresecurelytightened.Donotovertightenor
youmaydamagetheterminals.
• Whenconnectingloudspeaker cablesalwaysensurethe conductivesurfacesare
nottouching eachother.DONOTSHORT-CIRCUITTHETERMINALS.
Theremaybehighvoltagespresentattheloudspeakerterminals,whichcanbe
hazardousiftouched.Alwaysensuretheunit isswitchedto OFForSTANDBY
modewhenconnectingordisconnecting loudspeakers.
PRIORTOTURNING ONTHEUNIT,PLEASE CONTINUE TOREADTHE
FOLLOWING PAGES.

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ConnectingtheExternal Ground
The dm38isequippedwithaseparategroundterminal. Thegroundterminalhasa
greenbezelandislocatedunder thepowersupply. Thisterminalmaybeusedto
reducehumandrippleinsome circumstances.
Bridging
You maybridgetheHALCRO™amplifier,fordetailspleaseemail usat
[e-mail]
Abridging kitisavailablethroughHALCRO™.
Running-in period
The dm38’selectronicrunning-inperiodiscompletedatthefactory. Afurther
running-inperiodisnotrequired.
dm38InputSelections
The dm38hasthree switchselectableinputs,eachhavingaseparateinputsocket.Both
theinputsocketsandswitcharemountedonthetoprear panel.
Input
Styles Requiredoutput source impedance Input socket Inputimpedance
Balancedvoltage
input Lowimpedance.e.g., standardpreamplifier or
CDplayer etc.
XLR10kohms+10kohms
Un-balanced
voltageinput Lowimpedance.e.g., standardpreamplifier or
CDplayer etc.
RCA10kohms
Current-mode
input Very high: “infinite.”RCA60ohms

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Commentsonthedifferentdm38inputs
The balancedvoltageinputorcurrent-modeinputsaremostdesirableforminimizing
earthloop generatedmainshumandripple,or highfrequency interference.
Sourceswithcurrent-modeoutputsare rare andaremostlikelytohavean RCA
outputsocket.Theadvantagesofthissourcearethat:
• Earthloopgeneratedmainshumandrippleareminimized.
• Cable,plugandsocketgeneratedinterferenceisminimized(from poorconnections
whichmay beaffectedbysoundvibrationforexample).
The unbalancedinputisquitesatisfactoryso longasearthloopgeneratedmainshum
andrippleisnotaproblem.
Allorsome of theinputsocketsmay haveactivesourcessimultaneouslyconnectedto
them.Theselector switchselectsthe inputtobeamplified.

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OperatingInstructions
• Oncetheexternalcablesare connectedtothe unit,ensurethemasterON/OFF
switchisintheOFFposition. (ThemasterON/OFF switchissituatedonthebase
ofthelowercompartment,nearthemainssocketontheunit.Youwillhaveto
kneelontheflooratthebackoftheunitto accesstheswitch).
• Plug themainsplug intoamainsoutlet.
• Switchthe masterON/OFF switchtoON.The LEDsonthe frontandrear ofthe
amplifierwillglowred.Thisindicatesthattheunitisinstandbymode.Inthis
modeasmallcurrentisdrawnfromthe mainssupply, buttheunitwill notdrive
theloudspeakers.
• Pressthe modeswitchoncetoswitchbetweenStandbyandON modes.(Themode
switchisasmall pressureswitchaccessedwhenstandingat thefrontoftheunit.
It islocatedunderthebottomlipofthetopcompartment.
• Whentheamplifier hasbeenswitchedtoON,theLEDsonthefrontandrearwill
glowgreen.
• The amplifier isnowready todriveyourloudspeakers.
• Itisrecommendedthattheunitbeswitchedtostandby whennotinuse.
Itissafertoturn themainspower offwhennotusingthedm38.Howeverthe
amplifiermaybeleftoninthestandbymodeforprolongedperiods.Ifyouwishto
turnthemainspower off, the amplifierhasaveryminimalwarmup period.

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Electronic Protectionand Reliability
Electronicprotectioncircuitryandamplifierreliability,alas,isan areasadly neglected
bymanyhigh-endaudioamplifierdesigners.HALCRO™haspaidagreatdealof
attentiontothisarea.
Components
Our componentsareselectedfornotonlyperformancebutreliabilityaswell,for
example:
• AllHalcroelectrolyticcapacitorsareratedataminimumof105degreesCinstead
oftheusual85 degreerating. Theoperationallife ofelectrolyticcapacitorsis
severely shortenedattemperaturesnear the maximumtemperature rating. Thisis
showninthetablebelow.
• AllHalcrointegratedcircuitsareatleast “industrialgrade” ratherthanthe usual
“commercialgrade”.Industrialgradecomponentsareratedatleast from–40
degreesCto+85degreesCwhereascommercialgradecomponentsareonly rated
from0to70degreesC.Inaddition,the electronicspecificationsofindustrialgrade
componentsare superior tocommercialgrade.
Electrolytic
capacitor
temperature
rating
Meanlifetime at
40 degrees
Centigrade
Meanlifetime at
85 degrees
Centigrade
Meanlifetime at
105degrees
Centigrade
85 C (most
commonly used) 50,000Hours2,000Hours(0)
105C (usedin
Halcro
amplifiers)
180,000 Hours8,000Hours2,000Hours
Typicaldatafrom ahighly respectedmanufacturer.
Consideringthatmostamplifiersrunatsignificantly elevatedtemperatures,itcanbe
seenfromthetable,thattheHalcrohightemperatureratedcapacitorsarehighly
advantageouscomparedtothestandard85degreerateddevices.

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Outputcurrentlimiting
In termsofmaximumavailableoutputcurrent,therearebasically 3amplifiertype
options:
a.Anamplifierwithareasonablelimitplacedonthemaximumavailableoutput
current.
b.Anamplifier withnolimitplacedonthemaximumavailableoutputcurrent,which
will eitherblowafuseorselfdestructifexcessivecurrentisdrawn,forexample
throughadeadshort.
c.Anamplifierwithaveryhighlimitplacedonthemaximumavailableoutput
current,butdesignednottoblowafuseifthisveryhighcurrentisdrawn.
Ifthe maximumcurrentdrawnfroman amplifier withmaximumavailablecurrent
limitingisreachedundervery loudmusicconditions(amplifiertype a.orc.above),
highly obvious“cracking”overloadsoundsmaybeheard.Notethatthisoverload
soundmayalso occurifaloudspeakeroverloadsorif anyamplifiersuffersvoltage
overload.
Thereisan expectationintheaudiophileelectronicindustrythatahighendamplifier
shouldbecapableofdeliveringexactly doublethe outputcurrentfor a halving ofthe
loudspeakerimpedance(downto1ohm)atthemaximumoutputvoltagethatthe
amplifiercan produce.
Thisrequiresan amplifieroftype b.or c. above.Thetablebelowlistsan example ofan
amplifierratedat150 Wattsoutputinto8ohms.
Loudspeaker
load
impedance
Output
power Peakoutput voltage r.m.s. output current Peakoutput current
8ohms 150W49V4.33A6.12A
4ohms 300W49V8.66A12.25A
2ohms 600W49V17.32A24.5A
1ohm 1200W49V34.64A49.A
Ifthe loudspeakercableisinadvertentlyshortedout,thesesortsofcurrentsarequite
capableofcausingsome cablestocatchfire. Weknowofonesuchinstancewithan
amplifierratedaccording tothetable!
Aswedonotwishtosetyourhouseonfire wehavelimitedthepeakoutputcurrent
to15A.

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Onealso hastoquestionthebeliefthatan amplifiershouldbecapableofsuch
unreasonably highoutputcurrents.Consider the followingfacts:
• Mostloudspeakershaveimpedancesof4ohms(not1or 2ohms).
• Allvalveamplifiersareoutputcurrentlimited,andyetthe industrydoesnot
considerthisaproblem,whichisinconsistentwiththe belief thatmaximum
availablecurrentlimiting isaproblem.
• Allwelldesignedloudspeakershave impedancesthatdonotdeviateexcessively
fromtheirnominalimpedancesandhencenoexcessivelyhighcurrentsare
requiredanyway.
• Ifindeeda4or8ohmloudspeakerdoeshave animpedanceof1ohmata
particularfrequency,one mustwonderwheretheheatgeneratedisdissipatedif
thisloadispredominantly resistiveorwhythecouplingisso poorifthisloadis
predominantly reactive.
Hencewebelievethattheseexcessivelyhighoutputcurrentsare,
• notrequiredforwell designedloudspeakers,and
• highly dangerous.
Manypeople have listenedtomaximumavailablecurrentlimitedamplifiersplayed
throughdifferentloudspeakerswithoutencounteringanycurrentlimitingproblems
thatis,obvious“cracking”soundsatveryloudlisteninglevels,exceptforloudspeaker
orvoltageoverloadswhichareindependentofcurrentlimiting.
Outputtransistorprotection
Halcrouniquely incorporatescircuitrywhichaccuratelycalculatesthemean power
dissipatedinthepoweroutputtransistors(powerFETs).Anothercalculatingcircuit
thenmayreducethemaximumavailableoutputcurrentaccordingtotheheatsink
temperatureandcalculatedaveragedissipatedpowerinthetransistors.Thehigherthe
heatsinktemperature,andthe higherthe meanpowerdissipatedinthe output
transistors,the greaterthisreduction.Thiswillonly occur atveryhighheatsink
temperaturesandvery highmeanoutputpowers.

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Unusualoutputconditions
The vastmajorityofamplifierfaultsshowupashighpositiveornegatived.c.output
voltages.Anindependentcircuitinthe Halcroamplifierssensesanyunreasonabled.c.
outputvoltageandswitchestheamplifier offifthisoccurs.
Likewise,ifanyexcessiveoutputcurrentflowsforanextendedlengthoftime,this
alsoimpliesafaultandanindependentcircuitmeasuresthisandwillshutdownthe
amplifier.
Powersupply output currentlimiting
Tofurtherreducethepossibilityoffaultconditionscausingsubstantialdamage,the
powersupplyislimitedinitsmaximumavailableaverageoutputcurrent.Notethat
thislevelishigherthanthe amplifier’s normalcurrentlimitingconditions. Thepower
supply limitwillonly cutinunderfaultconditions.
Internal powersupply protection
Thereare numerouspowersupply protectioncircuits, forexample:
• Twoindependentover temperaturecutouts.
• Twoindependentmaster clockfaultsensingcircuits.
• Allpowersupplies,includingthosefor“housekeeping”standby,activepower
factorcorrectionandswitchmodepower etccheckforunder/overvoltageand
over currentconditions.
• The smallsignalpower supplieshave transientdiodeover-voltageprotection.
Mainstransientoverloadprotection
The mainsinputisprotectedagainstall butthe mostseveremainsinputtransients.
Threeindependentcircuitsachievethis:twosurgeabsorbersandhighenergy
inductivefiltering.
Inputoverloadprotection
The inputshaveover-voltageprotectioncircuits, whichwillhandlemosttypicalinput
overloads.
Amplifierinter-stageprotection
In additionwithinthe amplifierstages,therearemorethan adozenprotection
circuits.

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Specificationsforthedm38
POWER
Poweroutputinto4ohmsresistive>350W
Poweroutputinto8ohmsresistive>180W
DISTORTION (Footnote1).
Atfullpoweroutput,allharmonicdistortionorders
THD<-110dB (<3000partsperbillion)upto20kHz
(100kHzB.W.)at350Winto 4ohms.
THD@1kHz<-130dB(<300partsperbillion).
Forsumof19and20kHztones,eachdelivering100W
into 4ohms =peakpower350W,intermodulation
productseach<-110dBrelativetooutput.
SMPTE-IMintermodulationproductseach
<-110dBrelativeto output.
INPUTS
Thereare3inputmodes:
• Anunbalancedvoltagemodeinputwithan
impedanceof 10kohm
• Abalancedvoltagemodeinputwithanimpedance
of 10kohms +10kohms
• Acurrent-modeinputwitha60ohminput
impedancetominimizecable reflections (to befed
froman infiniteimpedancecurrentsource)
• Voltagegainofthebalancedandunbalanced
inputsis30V/V
• The gainofthe currentmode is 5V/mA
NOISE
Theequivalent inputnoiseattheinputis5nV/sqrt(Hz)
forthevoltagemodesand6pA/sqrt(Hz)forthe current
mode.
SLEWRATELIMIT: 100V/µs
POWERSUPPLY (Footnote2).
• Activepowerfactorcorrectionminimizes mains
currentharmonicdistortion
• 110Vmodeloperatesfrom100-120VRMS,45-
65Hz,
• 240Vmodeloperatesfrom220-240VRMS,45-65Hz.
• Lessthan 100 partspermillionmains humand
rippleontheamplifierpowerrails
• Conforms withallcurrentemissionandsafety
standards
OVERLOAD (Footnote3).
Recoveryfromhardoverloadat20kHzinto 4ohms:
1µs.
DIMENSIONS
• Height,31inchesor79cm
• Width, 16inchesor40cm
• Depth, 16inches or40cm
• Weight,120lbs. or55kg
• Shippingweight, 187lbs.or85kg
PROTECTION
THEAMPLIFIERPROTECTION:
• Isshort-circuitproof
• Hasovercurrentlimiting
• Willcutoutif temperatureisexcessive
• WillcutoutifacontinuousD.C. offset
appearsonoutput
• Willcutoutifoutputcurrentexceeds 10A
averagecontinuously overaperiodofafew
minutes
• Isprotected againstmostinputoverloads
THEPOWERSUPPLYPROTECTION:
• Willcutoutifmostcommonfaultsare
detected inthe powersupply (e.g.over-
voltage,masterclockatincorrectfrequency,
excessivetemperaturesetc)
• Isprotected againstmostmains transients
COMPONENTS (Footnote4).
• All semiconductorsareatleastindustrial
gradeinboththepowersupply andamplifier,
forreliability
• All electrolyticcapacitorsareexceptionally
longlifeindustrial grade inboththe amplifier
and powersupply
• Onlyhighly linearresistorsandthe lowest
impedancepolypropylenecapacitorsare
employedinthe criticalaudiopath
• 6-layerPCBsareused inthepoweramplifier
to minimizestraymagneticfieldsandto
accurately definevoltages
• 4-layerPCBsareused inthepowersupplyto
minimize E.M.I. andvoltagetransients, which
improvesreliabilityandpowerefficiency
COMPARTMENTS
Thereare3heavily shielded compartments:
• Powersupplyunit
• Inputamplifiersection
• Poweramplifiercompartment
FILTERING
Seriesand commonmodeEMIfiltering ispresent
• onthemainsinput
• between the amplifierand powersupply
Highfrequencyfilteringis presentatthe inputsand
output.
FOOTNOTES
1.THDspecificationsofour typicalbestcompetitorsare,
200,000partsperbillion.
2.Uniqueto thebest ofourknowledge.
3.Indicatesnoexcessivenegativefeedback.
4. "Industrial"gradeisahighergradethanthe "commercial"
gradeusedbymostmanufacturers.

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Careand Maintenance
TheHALCRO™dm38hasbeen designedforindooruseonly.Undernocircumstances
shouldtheamplifier beallowedtogetwet.Theonly maintenancerequiredwill be
ensuringtheunitiskeptclean.
Important
HALCRO™takesnoresponsibilityforanydamagecausedthroughcarelessor
improper cleaningtechniques.Never useflammableproductswhen cleaningthe
HALCRO™dm38.
Pleasereadthefollowing proceduresvery carefully
• The outersurfaceofthe unitisanodizedaluminum,whichwhilebeingvery
durable, willbemarkedifrubbedwithan abrasivecloth.
• Priortocleaning, turn the powertothe unitoffatthe mains.
• Useonlyextremelysoftcloths.
• Useasoftdryclothtoremoveanydust,particularly fromthe heatsink area.
• Add 15 mls(0.5oz)ofverymildhouseholddishwashingdetergenttoa4-litre(1
gal)bucketof lukewarm water.
• Immersethe softclothinthe bucketofwater, then wringthe clothoutthoroughly
untiltheclothisnearly dry.
• The slightly damp clothshouldonly ever beusedtoclean theanodizedaluminum
surfacesandtimberfeet.Neverclean anyelectricalfittings,terminalsorthefront
andrear Labelswiththedampcloth.Thelabelscan becleanedusinganextremely
softpolishingcloth,whichmustbedry.No moistureshouldeverbeallowedto
enterthe amplifier'scompartmentsthroughthejoinsinthepanels.
• Afterusingthe slightly damp cloth,wipeoverthesurfaceswithasoftdrycloth,
andthenallowthe amplifiertoair foratleastonehourpriortoturningthepower
back on.
• Ifyou areunsureaboutthe cleaning of theamplifierandrequiremoreinformation,
pleaseask yourdealeror contactHALCRO™at [e-mail]

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Troubleshooting
The HALCRO™dm38containsnouser serviceablepartsinsidethecompartments.
Pleasedonotattempttoopen the unitasthis willvoidthewarranty andwillexpose
youtodangerousvoltages. Forallservicerequirementspleasecontactyourdealer,or
HALCRO™at [e-mail]
SymptomSuggestion
NoSoundorlight1.Ensuremainscableispluggedintothe amplifier.
2.Ensurethemainscableispluggedintoaworking
wallsocket.
3.EnsuretheMaster SwitchisON.
4.Check Fuse.
Redlightison,
Nosound 1.PresstheStandby /ON switchtoON.
Green lightison,
Nosound 1.EnsureInputSelectorSwitchissettothecorrect input.
2.EnsureLoudspeakerCablesarecorrectly connected
(bothends).
3.EnsuretheInputcablesarecorrectly connected(both
ends).
4.Check preamplifier isonandcorrectly connected.
5.Checkforasignalfromthe preamplifier (with
headphonesifavailable).
6.Check audiosourceisonandcorrectlyconnected.
7.Checkforasignalfromtheaudiosource(with
headphonesifavailable).
8.Tryadifferentaudiosource.
Ifnoneoftheaboverectifiestheproblempleasecontactyour dealerforservice.

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Service
The HALCRO™dm38 hasbeendesignedformaximumreliability. Ifaproblem does
occur withyour unit,pleasecontactyour dealer.
Contactyour dealer tohelpyou withsometroubleshootingpriortoorganizingservice
foryouramplifier. YourdealerorHALCRO'Sservicedepartmentwillalwaystry to
help youcorrectanybasicproblemsatyourhome viaemailortelephone.
Ifserviceisrequired,allproblemsmustbedescribedinasmuchdetailaspossible.
Thiswill help streamlinetheserviceprocess.
Return authorizationfromHALCRO™priortoshipmentmustbeobtainedforany
servicerequirements.Toobtainthisauthorization,pleaseaskyourdealer oremail us
at [e-mail]
The originalpackagingisrequiredforshippingpurposes.HALCRO™willnotbe
responsiblefor anydamagecausedtoyouramplifierduringshippingduetoimproper
packaging.If thepackagingneedstobereplacedonitsarrivalatthefactory,the
owner couldbechargedreplacementcosts.

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Warranty
IMPORTANT-Please readthefollowingdetailsvery carefully
The dm38iswarrantedtobefreeofdefectsifusedundernormalconditionsfora
periodofninety (90) daysfromthedateof purchase.Toextendthewarrantyperiodto
five(5) years, pleasecompleteandreturnthewarrantyregistrationform.
Asmentionedpreviously,donotattempttoopen upanyoftheamplifier
compartments.Thecompartmentsaresealedatthefactory. Ifanyofthe sealsare
broken,thewarrantywillbevoidandallservice,repairandfreightcostswillbe
chargedtotheowner.Willfuldamage, tampering, anddamagecausedbymoistureare
notcoveredby thewarranty.
The warrantywillonly berecognizedbyHALCRO™ifacopy oftheoriginalreceipt
fromyourdealershowingalldetailsincludingthedateofpurchase,accompaniesa
copy ofthecompletedwarrantyregistrationform.Thewarrantyperiodwill
commenceatthe dateofpurchase,notatthedatethe warrantyregistrationform is
receivedby HALCRO™.
Return authorizationfromHALCRO™priortoshipmentmustbeobtainedforany
warrantyrequirements.Toobtainthisauthorization,pleaseemailHALCRO™at
[e-mail] orfax [phone].
The originalpackagingmustbeusedforshippingtheamplifierforwarranty
requirements.Thiswillensure thesafetyoftheamplifier. Ifyou havemisplacedor
damagedtheoriginalpackaging,youcanpurchasenewpackagingthroughyour
dealer orHALCRO™.
The warrantyregistrationform isincludedinthisowner'smanualonthefollowing
page.Pleasecutitoutcarefullyalongthe lineupthe left-handsideofthepageand
returnittoHALCRO™. YouwillfindHALCRO'Saddressandfacsimiledetailsonthe
warranty registrationform.
PLEASECOMPLETEALLSECTIONS OFTHEFORM.FAXORPOSTTHE
COMPLETED WARRANTY REGISTRATION FORMTOHALCRO™
IMMEDIATELY.WE WILLTHEN NOTIFYYOUOFITSARRIVAL AND
ACCEPTANCE.

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Warranty RegistrationForm
Oneform mustbecompletedforevery amplifier.
Title……………
Firstname………………………….. Surname………………………......................................
Address………………………………………………….…………………………………......
…………………………………………………………………….………………………….....
Zip or postcode………………………Country………………………………………...........
DateofBirthDay………..Month………….Year…………..
PhonenumbersHome (……)…………………….. Work (……)…….……………............
FacsimilenumbersHome(……)…………………Work (……)…….........……………….
Email address………………………………………………
PRODUCTDETAIL
Modelnumber dm38
Serialnumber………….. (locatedonabadgeatthebottomofrear panel)
DateofpurchaseDay..……….Month………..Year…………..
Purchasedfrom(Dealername)….…………………….....……………….………………...
You mustattachacopy oftheoriginalreceiptforthe warranty tobeaccepted.
Pleasedescribethe mainfunctionfor the amplifier.
DomesticuseCommercialuseDemonstrationuse
Pleaserefer tothepreviouspagefordetailsof the warranty periodforyour model.
Postto, HALCRO,
118 HaywardAvenue,
Torrensville,SouthAustralia5031.
Faxto, [phone]