McIntosh MAC 4100 User manual

THEMCINTOSHMAC4100RECEIVER
ReadingTime: 48Minutes
Price$2.00

VARIOUSREGULATORYAGENCIESREQUIRETHATWEBRINGTHEFOLLOWINGINFOR-
MATIONTOYOURATTENTION.PLEASEREADITCAREFULLY.
WARNING:TOPREVENTFIREORSHOCK
HAZARD,DONOTEXPOSETHISUNITTO
RAINORMOISTURE.
TheMclntoshyouhavepurchasedisa Model
MAC4100.Ithasa serialnumberlocatedontherear
panelofthechassis.Recordthatserialnumber
here:
SerialNumber
Themodel,serialnumberandpurchasedateareim-
portanttoyouforanyfutureservice.Recordthepur-
chasedatehere:
PurchaseDate
Uponapplication,MclntoshLaboratoryprovidesa
Three-YearServiceContract.YourMclntosh
authorizedServiceAgencycanexpediterepairs
whenyouprovidetheServiceContractwiththein-
strumentforrepair.Toassist,recordyourService
Contractnumberhere:
ServiceContractNumber

YourMAC4100SolidStateAM-
FM/FMStereoReceiverwillgiveyou
manyyearsofpleasantand
satisfactoryperformance.Ifyou
haveanyquestions,pleasecontact:
CUSTOMERSERVICE
MclntoshLaboratoryInc.
2ChambersStreet
Binghamton,NewYork13903
Phone:[phone]
Contents
TakeAdvantageof3 years
ofContractService...
FillintheApplicationNOW.
INTRODUCTION...2
INSTALLATION...3
HOWTOCONNECT...5
WHATTHEFRONTPANELCONTROLS
DOANDHOWTOUSE THEM.. .10
PUSHBUTTONS...10
FRONTPANELINDICATORS. . .12
BALANCINGYOURSTEREO. ..13
LISTENINGTOYOURSTEREO. ..13
MAC4100PERFORMANCELIMITS...15
TECHNICALDESCRIPTION. ..16
PERFORMANCECHARTS...20,21,22,23
BLOCKDIAGRAM...24
MCINTOSHTHREEYEARSERVICECONTRACT
Anapplicationfora THREEYEARSERVICECONTRACTisincludedwiththismanual.
Thetermsofthecontractare:
1.Mclntoshwillprovideallparts,
materialsandlaborneededtoreturnthe
measuredperformanceoftheinstru-
menttotheoriginalperformancelimits.
TheCONTRACTdoesnotcoverany
shippingcoststoandfromtheauthoriz-
edserviceagencyorthefactory.
2.AnyMclntoshauthorizedserviceagen-
cywillrepairMclntoshinstrumentsat
normalservicerates.Toreceiveservice
underthetermsoftheSERVICECON-
TRACT,theSERVICECONTRACTCER-
TIFICATEmustbepresentedwhenthe
instrumentistakentotheservice
agency.
3.Alwayshaveservicedonebya
Mclntoshauthorizedserviceagency.If
theinstrumentismodifiedordamaged,
asa resultofunauthorizedrepairthe
SERVICECONTRACTwillbecancelled.
Damagebyimproperuseormishandl-
ingisnotcoveredbytheSERVICECON-
TRACT.
4.TheSERVICECONTRACTisissuedto
youastheoriginalpurchaser.Topro-
tectyoufrommisrepresentationthis
contractcannotbetransferredtoa se-
condowner.
5.ForyourprotectionMclntoshselects
onlydealerswhohavetechnicalcom-
petencetoguidepurchasersfairly,and
provideservicewhennecessary.To
receivetheSERVICECONTRACTyour
purchasemustbemadefroma
Mclntoshfranchiseddealer.
6.Yourcompletelyfilledinapplicationfor
aSERVICECONTRACTmustbepost-
markedwithin30daysofthedateof
purchaseoftheinstrument.
7.ToreceivetheSERVICECONTRACTall
informationontheapplicationmustbe
filledin.TheSERVICECONTRACTwill
beissuedwhenthecompletelyfilledin
applicationisreceivedatMclntosh
LaboratoryIncorporatedinBingham-
ton,NewYork.
Copyright1978© byMclntoshLaboratoryInc.
1

Introduction
TheMclntoshMAC4100isa highquality,high
powerAM/FMStereoReceiver.Itsdesignhasbeen
governedbyinsistenceongreatflexibility,sensitivi-
ty,highperformancewithlonglife.Itiseasytouse.
Someofthemanynewimprovementsdesigned
foryourlisteningenjoymentInclude:
Lownoisefieldeffecttransistoranaloginputswit-
chingthatkeepssignalleadsshorttoreducepossi-
blenoiseandhumpickup.Mechanicalcontactnoise
isalsoeliminated.
LEDInputindicatorsshowwhichsourcehasbeen
selectedandhelpmakeinputselectionfaster,
easier,surerandmoreconvenient.
Newlowimpedancetransistortechnology
reduceshumandnoiseinterferenceinthephono
preamplifier.
Electronicallycontrolledtrimmingofthepreci-
sionsteppedvolumecontrolmaintainsa channelto
channelaccuracyof1 dB.Thishighorderofexact-
nessassurescontinuingprogrambalanceasthe
listeningloudnessischanged.
Thefivebandprogramequalizerpermitsthead-
justmentandimprovementofthetonecontrastof
thefivemostimportantlisteningranges.Eachcan
beemphasizedorde-emphasizedtosatisfyyour
tasteorlisteningatmospherewithoutaffectingany
oftheotherranges.
Thehighqualitypowerperformanceiscon-
tinuouslyassuredbyPOWERGUARD.ThePOWER
GUARDcircuitdynamicallypreventspower
amplifiersfrombeingoverdrivenintohardclipping--
-whichprotectsyourspeakersfrompotential
damage- - - whichassuresthattheamplifierwillpro-
duceitsmaximumoutputwithoutincreaseddistor-
tion.Thepowerdeliveredis100wattsperchannelat
4ohmstogiveextradynamiclifetoyourmusic•
evenwhenyou'reusinganycombinationof3 setsof
stereoloudspeakers.
Theselectivelylighteddial pointerlightsonlythe
relevantpartofthetuningindicatortomaketuning
easier.
AutomaticACpowercontrolisprovidedbythe
autoOn/Offcircuitthatconvenientlyshutsoffthe
entiresystemwhentheturntableshutsoff.Noneed
tointerruptyourpleasureattheendoftherecord.
Frontpaneltaperecorderjacksallowsimpleplug
Inofan"outboard"taperecorderwithoutupsetting
yourregularsystemconnections.
Copiesoftapescanbeeasilymadebetweentwo
connectedtaperecorders.Frontpaneltapecopying
controlsfunctionwithoutdisturbingothersound
sources.
Thisoutstandingreceiverwillserveyoubestwhen
youunderstanditsfunctionsandwhatitisdesigned
todo.Sometimeinvestedwiththismanualwillbe
valuableinyourknowledgeofhowitworks.
2

x8"[20.32cm],[seeFig.2].Inaddition,a single3/8"
to1/2"[1cmto1.3cm]screwhole[seeFig.2 and
Fig.3]mustbedrilledintheshelftosecurethe
receiverafterinstallation.Thetopoftheshelfmust
beattachedflushwiththebottomofthecustom
panelcutout.
BOTTOMOFPANELCUTOUTAND
TOPOFSUPPORTSHELFMUSTCOINCIDE
Fig.1 CustomCabinetFrontPanelCutout.
TheMAC4100maybeusedona shelfortabletop
intheenclosureinwhichitcomesormaybeinstall-
edina customcabinet.Inanymethodofuseprovide
adequateventilation.
Thetrouble-freelifeofanelectronicinstrumentis
greatlyextendedbyprovidingsufficientventilation
topreventthebuild-upofhighinternaltemperatures
thatcausedeterioration.Allowenoughclearanceso
thatcoolaircanenteratthebottomofthereceiver
andbeexhausedfromthetopandrear.Withade-
quateventilationtheinstrumentcanbemountedin
anyposition.
TheMAC4100isinstalledfromthefrontofa
customcabinet.Thedesirablespacebehindthe
cabinetpanelis15"[38.1cm]deep,18-1/2"[47cm]
wide,and6"-[15.2cm]high.Theunitfitsanopening
exactly5-1/16"[12.9cm]by17-5/16"[44cm]wide.
Makethiscutoutcarefully.Thereceiver'sfrontpanel
hasa 1/8"[.32cm]overhangonbothsidesanda
3/32"(.24cm)overhangonthetopandbottom,[see
Fig. 1].
Theweightofthereceivermustrestona shelfin
whichthereisa ventilationholecutout15"[38-1cm]
PreparetheMAC4100forcustommountingby
removingthewoodcabinetandfeetasfollows:
1.Remove4 screws"A"[seeFig.4];twofromeach
sidepanel.
2.Toremovetheenclosuretoppanel,thereceiver's
metaltopmustbetemporarilyremoved.Itisat-
tachedtothechassisby4 screws"B"[seeFig.4]
installed2 throughtheflangeonthebackand1
througheachoftheflangesontheside.Remove
these4 screws.Savethescrewstoreinstallthe
metaltopafterremovaloftheenclosuretop
panel.
3.Underthemetaltopare5 screws"C"thatholdthe
enclosuretoppaneltothemetaltop[seeFig.4].
Removethe5 screws"C"thatholdthemetaltop
totheenclosuretoppanel.
4.ReplacethemetaltopontheMAC4100withthe4
screws"B".
5.Onthebottomofthereceiverarethe4 plasticfeet
heldonbyscrews"D"[seeFig.4].Removethese
feet.Donotattempttoremovethe4 plasticbut-
tonglidesastheserestagainsttheshelf,(seeFig.
2and3).Atthispointthereceiverisreadytobe
custominstalled.
Fromthefrontofthecabinet,threadthepower
cordthroughtheopeninginthecabinetpaneland
slidetheMAC4100inontheshelf.Adjusttheposi-
tiontoevenlycoverthecustompanelcutout.Lock
theunitinplacewitha screwandwasherinserted
throughthedrilledholeinthemountingshelf[see
Fig.3].Usea 1-1/4"[3.2cm]screwfor1/2"[1.3cm]
shelfora 1-1/2"[3.8cm]screwfor3/4[1.9cm]shelf.
Donotuselongerscrews.
EDGEOF4100FRONTPANEL
3

MAC4100UNITOUTLINE(DOTTED)
MOUNTINGSURFACE
MOUNTINGPANEL
Fig.2 CustomCabinetShelfMountingCutout.
MOUNTING
SURFACE
15"(36.1cm)
MINIMUMDEPTHREQUIRED
FOR1/2"SHELFUSE1 1/4"SCREW
(1.3cm)(3.2cm)
FOR3/4"SHELFUSE1 1/2"SCREW
(1.9cm)(3.8cm)
MOUNTING
PANEL
PLASTIC
BUTTONS
CUTOUTFOR
VENTILATION
SECUREUNIT
WITHSCREWAND
WASHER
Fig.3 MAC4100CustomMountingProfile
Fig.4 MAC4100EnclosureAssembly
4

HowtoConnect
CONNECTINGTURNTABLES
TheMAC4100hasshortingplugsinthephonoin-
puts.Topreventunwantednoiseremoveonlythe
shortingplugsfrominputjacksthatare10beused
Connectthecablefromtheleftchanneloftheturn-
tableintotheINPU1L PHono1 jack.
Connectthecablefromtherightchannelofthe
turntableintotheINPUTR PHono1 jack.Connect
PHono2 inthesamewayforusewitha secondturn-
table
CONNECTINGTAPERECORDERS
ToRecord
Connecta cablefromtheRECORDERL TAPE1
OUTjacktothelefthighlevelinputofthetape
recorder.Connecta cablefromtheRECORDERR
TAPE1 OUTjacktotherighthighlevelinputofthe
taperecorder.Connecta secondrecorderinthe
samemannertotheRECORDERTAPE2 OUTjacks.
ToPlayback/Monitor.
Connecta cablefromtheleftchanneloutputofa
taperecordertotheRECORDERL TAPE1 INjack.
Connecta cablefromtherightchanneloutputofa
taperecordertotheRECORDERR TAPE1 INjack.
Connecta secondrecorderinthesamemannerto
theRECORDERTAPE2 INjacks.
FrontPanelTapeRecorderJacks:
Taperecorderinputsandoutputsareavailableat
theTAPEIN-OUTjacksonthefrontpanelleftofthe
INPUTSELECTORswitch.Rapid,temporaryconnec-
tionstoTAPE2 facilitiesareeasilymadewithout
gettingattherearpanel.A metalshielded1/4"
stereophoneplugisusedConnectionsaretip:left
signal,ring:rightsignal,and.sleeve:common
ground.
Whena taperecorderispluggedintothefront
jacksallthefacilitiesnormallyassociatedwith
TAPE2 ontherearpanelareautomaticallytransfer-
redtothefrontpaneljacks.
CONNECTINGACPOWER
ThereceiverACpowercordispluggedintoa 120
volt6OHzwalloutlet.
TherearethreetypesofACpoweroutletsonthe
backpaneloftheMAC4100onered.twoblack,and
twogreen
TheredandthegreenACpoweroutletsareonat
alltimes.Theredoutletcanbeusedfora tape
recorderwithitsownACpowerswitch.PlugtheAC
powercablesfromtheturntableintothegreen
TURNTA8LEpoweroutletsontherearpanel
Thetwoblackoutletsareswitchedonandoff
whenthereceiveristurnedonoroff.Thesearein-
tendedforequalizersandotheraccessories.
ThePOWERONpushbuttonsharesACpower
control,withtheACpowerswitchona turntable,
througha currentdetectingswitchcircuitOnme
rearpaneltheTURNTABLEAUTO/MANUALswitch
selectsthemodeofoperation.
WhentheswitchisintheAUTOpositionanda
turntablepluggedintooneofthegreenACpower
outlets,theACpowertothereceiverandtothe
blackACpoweroutletscanbecontrolledbythe
turntableon/offswitch.WhenACpowertotheturn-
tableisturnedon,automaticallythereceiverandthe
SWITCHEDblackACpoweroutletsareturnedon
Thesystemwillremainonuntiltheturntableisturn-
edoil.ThePOWERONpushbuttoncontrolstheAC
powerloranysourceotherthantheturntable.
IntheMANUALpositiononlythePOWERON
pushbuttonwillturnACpoweronoroff
Someturntableshaveelectroniccircuitsthat
drawcurrentallthetime.Tousetheseturntablesthe
AUTO/MANUALswitchmustbeintheMANUAL
position.WiththeAUTO/MANUALswitchinthe
MANUALposition,ACpowertothesystemwillbe
controlledbythefrontpanelPOWERpushbutton
only.
5

ThegreenACpoweroutletsareprotectedwitha
oneampfuse.Anyincreaseinthevalueofthisfuse
willaffecttheprotectionofthesensingcircuitand
maycausedamage.
AVHF-TVantennacanbeeffectivewhenitis
designedforbothFMandTVreception.Connectthe
twoleadsfromtheVHF-TVantennatotheANTEN-
NA300WFMpushconnectors.
CONNECTINGPROGRAMSOURCEGROUNDS
AsingleGROUNDpostisprovidedtowhich
groundsforturntables,recordchangers,tapedecks,
etc.areconnected.Topreventhumpickup,theleft
andrightprogramcablesandthegroundwirefrom
thatsourceshouldbewoundortwistedtogether.
Makesurethegroundwiredoesnotmakeanycon-
nectiontotheshieldsoftheleftandrightprogram
cablesbetweenthesourceandtheinputoftheMAC
4100.
FMPRESELECTORSWITCH
FMreceiverscanbeoverloadedbyverylarge
antennainputsignalswhenthereceiverislocated
veryneartoa FMbroadcastingstationorwhena
highgaindirectionalantennaisusedina
metropolitanarea.
Thepreselectormaybeswitchedintooroutofthe
FMRFcircuitbya slideswitchlocatedontheMAC
4100rearpanelneartheAMantenna.
WerecommendthattheFMPreselectorswitchbe
usedinthe"out"positionforallFMlisteningcondi-
tionsexceptwherethereisevidenceofoverloadby
strongstations.Inthatcase,the"in"positionwill
immunizeagainstoverload.Formoststationsthere
willbenolisteningdifferencebetweenthetwo
switchpositions.
MAC4100receiverswithserialnumbersbelow
BY3000donothavetheFMpreselectorswitch
describedabove.
CONNECTINGANFMANTENNA
Oneofthreeantennasystemscanbeused:[1]an
outdoorFMantenna,or[2]a VHF-TVantenna,or[3]
theindoordipolesupplied.
Anoutdoorantennaisrecommendedforoptimum
performanceinallareas,Infringe[outlying]areas,
bestresultswillbeobtainedwitha highlydirec-
tionalFMantennausedinconjunctionwitha
rotator.Iftheantennausesa 300ohmlead,connect
ittotheANTENNA3000FMpushconnectors.
Thecoaxialcableofanunbalanced75ohmanten-
naconnectstotherearpanelANTENNA750FM
typeF coaxialconnector.
Anoutsideantennasystemshouldnotbelocated
inthevicinityofoverheadpowerlinesorotherelec-
triclightorpowercircuits,orwhereitcanfallinto
suchpowerlinesorcircuits.Wheninstallinganout-
sideantennasystem,extremecareshouldbetaken
tokeepfromtouchingsuchpowerlinesorcircuits
ascontactwiththemmightbefatal.
CONNECTINGANINDOORDIPOLEANTENNA
Theflexiblefoldeddipoleantenna[300ohm]isfor
useinurbanorhighstrengthsignalareas.Connect
thetwoleadsfromthedipoletotheANTENNA300W
FMpushconnector.
Theflexibilityofthetwinflatwireassemblyper-
mitsittobeplacedundera rug,tackedbehindthe
stereo...orplacedinanyotherconvenientlocation.
Insomecases,itmaybenecessaryto"position"the
antennaforbestsignalreception.Thisshouldbe
donebeforeitispermanentlylocated.
Avoidlocatingtheantennanexttootherwiresor
metalobjects.Anyindoorantennamaybeineffec-
tiveinhouseshavingmetalsidingormetalfoilin-
sulation.
AMANTENNA
ForlocalandmostmoderatelydistantAMrecep-
tionthebuilt-inferriteloopstickantennamaybeus-
ed.TheAMloopstickantennaisona swivelbase
andmustbeadjustedawayfromthechassisforbest
reception.
Distantreceptioncanbeimprovedwiththeuseof
acopperantennawire50to150feetinlength.Sus-
pendthewireina straightlineashighaspossible.
Attachthewireateachendwithsuitableglassor
ceramicinsulators.Connecta lead-inwireatany
convenientpointontheantenna.Itisrecommended
thata lightningarresterbeusedwithanoutdoorAM
antenna.Thearrestershouldbewellgroundedtoa
groundrodorcoldwaterpipe.
CONNECTINGA MAXIMUM
PERFORMANCEINDICATOR
ThescopeTP1andTP2jacksontherearpanelare
usedtoconnecta Mclntoshmaximumperformance
indicatororanoscilloscope.Followdirections
outlinedinthemaximumperformanceindicator
owner'smanual.
FUSES
A4-ampSLOBLOfuseprotectsthereceivercir-
cuits.Thefusedoesnotprotectadditionalequip-
mentconnectedtotherearpanelACpoweroutlets.
Aoneampfuseprotectstheturntableautooncir-
cuit.Ifthisfuseopens,powertothegreenoutlets
willbeinterrupted.
6

7

CONNECTINGLOUDSPEAKERSFORSTEREO
Allspeakersareconnectedtothepushconnec-
torsontherearpanel.Whenstereospeakershave
beenconnectedtotheproperpushconnectors,the
correspondingfrontpanelpushbuttonsturnthe
speakersonoroff.
Selectionoftheproperguagewiretoconnectthe
loudspeakerspreservesthequalityofsoundrepro-
ductionforwhichtheloudspeakershavebeende-
signed.Ifundersizewireisused,resistanceisadded
tothereceiver/loudspeakercombinationwhich
adverselyaffectstheperformance.Addedresis-
tancecausesreductionofdampingcharacteristics,
modificationoffrequencyresponseandreductionin
poweroutput.
Uselampcord,bellwire,orwirewithsimilartype
ofinsulationtoconnectthespeakerstotheam-
plifier,inallcases,theleadstoandfromthespeaker
shouldbetwinconductorortwistedtogether.When
using8 ohmspeakersandforthenormallyshort
distancesofunder30feetbetweentheamplifierand
speaker.No.18wireorlargercanbeused.For
distancesover30feetbetweenthereceiverand
speakeruselargerdiameterwire.Selectthecorrect
sizewireforthewirelengthfromthechart.Itis
recommendedthattheDCresistanceofthespeaker
leadsbelessthan5%ofthespeakerimpedance.Up
to10%canbetolerated.Resistanceoftheleads
shouldbecomputedforthelengthofwirebothto
andfromthespeakerorspeakers.Theheaviergauge
wiresmaynotfitintotheholesinthespeakerand
receiverterminals.Attacha shortpieceoflighter
gaugewireandthenconnecttotheterminals.
MAXIMUMWIRELENGTHS
WireFor4 OhmLoadFor8 OhmLoad
Gauge
22
20
18
16
14
12
10
Wirelengthsaboverepresentthewireresistanceequalto5%
ofthespeakerimpedance
Formultiplespeakeroperation,runseparate
leadsfromthereceivertothespeakers.
Connecttheleadsfromtheleftmainloudspeaker
totheSPEAKER1 LeftandCommonpushconnec-
tors.Connecttheleadfromtherightmain
Feet
6
10
15
25
40
60
100
Meters
1.8
3.1
4.6
7.6
12.2
18.3
30.5
Feet
12
20
30
50
80
120
200
Meters
3.7
6.1
9.1
15.2
24.4
36.6
66.0
loudspeakertotheSPEAKERI RightandCommon
pushconnectors.Connecttheleadsfroma second
leftloudspeakertotheSPEAKER2 LeftandCom-
monpushconnectors.Connecttheleadfroma se-
condrightloudspeakertotheSPEAKER2 Rightand
Commonpushconnectors.Connecttheleadsfrom
athirdleftloudspeakertotheSPEAKER3 Leftand
Commonpushconnectors.Connecttheleadfroma
thirdrightloudspeakertotheSPEAKER3 Rightand
Commonpushconnectors.
CONNECTINGONELOUDSPEAKERFORMONO
TheleftandrightoutputsoftheMAC4100mustcon-
necttoseparateloudspeakers.Donotparallelthe
outputconnectionsfora singleloudspeaker.Ifthe
leftandrightoutputsareconnectedtogetherex-
cessiveheatisgeneratedinthepoweramplifiers
whichcausesdamageeventhoughtheMODE
SELECTORpushbuttonisintheMONOposition.If
youwishtodrivea singleloudspeaker,putthe
MODESELECTORinMONOandconnecttheloud-
speakertotheleftortherightspeakerpushconnec-
torsonly.Itisnotnecessarytoconnecta loadtothe
otherchanneloutput.
CONNECTINGAMCINTOSHEQUALIZER
OntheJUMPERpanel,removethejumpersbet
weenthePREAMPOUTjacksandPOWERAMPIN-
putjacks.Theenvironmentalequalizerisconnected
betweenthesejacks.Standardshieldcablescon-
nectthePREAMPOUTtotheinputoftheequalizer.
ConnecttheoutputoftheequalizertothePOWER
AMPINputjack.
CONNECTINGOTHERPOWERAMPLIFIERS
ExternalpoweramplifiersmaybefedtotheMAC
4100intwoways:
1.FedfromtheRECORDERTAPEOUT.Theout-
putatthispointisnotaffectedbythevolumeor
equalizingcontrolsoftheMAC4100.Usethisoutput
todriveanamplifierwhichhasitsowncontrols.A
possibleusewouldbetooperateanindependent
systemina remotelocationwherevolumere-
quirementsneedtobelocallycontrolled.
2.FedfromtheAMPLIFIER- PREAMPOUT
jacks.Theoutputatthesejacksisaffectedbythe
VOLUME,EQUALIZER,BALANCE,andLOUDNESS
controls.Usethisconnectiontodriveanamplifier
withoutcontrolsofitsown.orwheretheinfluenceof
thecontrolsoftheMAC4100arewantedonall
loudspeakers.
8