C504
BESTCOMPACTPREAMPLIFIER!
Whenyouneeda reliable,townoiseflexible
preamplifierina compactsize,youneedthe
MclntoshC 504.
Thevaluestolookforina preamplifierare:
1.QUALITYCONSTRUCTION
2.RELIABILITY
3.MECHANICALSTRENGTH
4.ELECTRONICSTABILITY
5.CONVENIENCEOFOPERATION
6.VERSATILITY
7.SUPERIORPERFORMANCE
TheMclntoshC 504isa hightechnology
preamplifierina compactnewcasesize.The
featuresandperformanceoftheC 504reflectthe
latestinMclntoshLaboratoryengineeringdesign
excellence.
PRECISIONTRACKINGVOLUMECONTROL
Thevolumecontrol,manufacturedforMclntosh
Laboratory,isa stepattenuatorwhichhastracking
accuracywithin1 dBthroughoutitsentirerange.
Suchextremelyaccuratematchingisachieved
throughelectronicallycontrolledtrimmingofthe
resistancematerialdepositedonpairsofminiature
printedcircuits.Trackingaccuracyandquietperfor-
mancearepermanentlymaintained.Usedoesnotaf-
fectperformanceasinordinaryvolumecontrols.
TRUELOUDNESSCOMPENSATION
TheC 504activecircuitloudnesscontroliscon-
tinuouslyvariable,withconstantmidrangegainand
actsindependentlyofthevolumecontrol.The
loudnesscontourisaccuratelymodeledafterthe
FletcherMunsomfamilyof"EqualLoudness"
curves.Useofthiscontrolrestoresproperlistening
responseateventhesoftestlisteninglevels.
FETANALOGINPUTSWITCHING
Allcriticalinputswitchingisdoneelectronically
usingfieldeffecttransistoranalogswitches.The
frontpanelselectorsimplyswitchessmallamounts
ofcontrolDCvoltagewhichturntheFETanalog
switchesonoroff.SincetheFETanalogswitches
arelocatedneartheinputjacks,thelengthofinter-
connectingleadsismuchshorter.Noise,switching
transients,andhumpickupareeliminated.
TRI-FREQUENCYPROGRAMEQUALIZER
Threeseparatecontrolsallowthebalanceand
responseofmusicalinformationtobeadjustedwith
farmoreflexibiltythanwithconventionaltonecon-
trols.Thecenterfrequenciesofthecontrolsare30
Hz,750Hzand10KHz.Plusandminus12dBofcon-
trolisavailable.Useoftheprogramequalizercon-
trolsdoesnotaffectintheslightest,thelownoise,
lowdistortionperformanceofthepreamplifier.
Whentheequalizercontrolsareintheircenterorflat
detentposition,theiractionisneutralandresponse
ofthepreamplifierisabsolutelyflat.
HEADPHONE/OUTPUTAMPLIFIER
Themainoutputamplifiersectionofthe
preamplifierisa push-pullcomplementaryclassAB
circuit.Becauseoftheextremelylowdistortionand
powercapabilityofthiscircuititisusedforboth
mainandheadphoneoutputs.
INTEGRATEDCIRCUITOPERATIONALAMPLIFIERS
Boththemagneticphonoandtheequalizer
amplifierstagesutilizenewhightechnologyin-
tegratedcircuitoperationalamplifiers.Noisefac-
torsareincrediablylow,anddistortionlevelsareat
orbelowthelimitsofpresentdaytestequipment.
showninoptionalwalnutveneercabinet
