Am 833S User manual

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833SMonoblockAmplifierManual.
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CongratulationsonyourpurchaseoftheAMMusic833S,PureClassA,SingleEnded
Monoblocks.YouarenowtheownerofoneoftheWorld’sfinestamplificationsystems.This
amplifieristheculminationof14yearsofcarefulresearchanddevelopment,inthesearchof
themythicallyperfectamplifier.Webelievedthatwehaveachievedthiswiththisamplifier.
Unpackingandassembly:
Carefullyremovertheamplifiercomponentsfromtheircartons.Themodulesareveryheavy
andcareshouldbetakentonotdamagetheamplifierorcauseyourselfinjuryinliftingthem.
Havingtwopeopleavailableisadvisable.
Carefullyunpackthe833tube.Thetubemounthastwothumbscrewstosecurelyholdthetube
inplace.Thisisaccessedbyunscrewingthe4chromeknobsoneachcornerofthetube
surround.

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Removethe4screws(asshown)andcarefullyliftthe
surroundbyabout8cmtoalloweasyaccess.
(Asshownbelow)
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
Insertthe833tube,makingsurethatitisinasfaras
itwillgo,andfirmlytightenthetwothumbscrews.
Replacetheassemblyandrefitthe4screws,
tighteningthemuntiltheyarefirm,butdonotover
tighten.
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
FitthetwoTefloncapstotheelectrodesontopof
thetube.UsinganAllankey,tightenthegrubscrew
asshowntoensurethatthecapissecuredtothetop
ofthetube.(Seefollowingwarningonnextpage)
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WARNING.TheAMMusic833Sdoesnotrunattheexcessivelyhigh
voltagesofsomeotherSuperAmps,butthereis900Vpresentatthetopcaps,
whentheamplifierisswitchedon.Thisvoltagecanbeextremelydangerous,
andifthecapisremovedwheninoperation,asevereelectricshockispossible.
Itisthereforeveryimportantthatthecapsaresecuredbydoingupthegrub
screwtopreventanyinexperiencedpersonremovingthecap.Ifproperly
secured,itiscompletelysafe.Thevoltagedropstozeroassoonasthepowerisswitched
offandthegreenoperatinglightisoff.Ensurethatthepowerisoffandthepower
leadisremovedbeforeattemptingtoremoveoraccessthetube.
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Connectthetwoumbilicalcordsbetweeneachamplifierandthecorrespondingpowersupply.
Theseleadsare1.5minlengthandtheamplifiersectioncaneitherbeplacedontopofthe
powersupply,orwhereverelsesuitsinyourinstallation.
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Eachplughasseveralguideridgesonit.Thereisonethatismuchthickerthantheothers.(As
seeninrighthandphotograph)Thisoneisalwaystothetop,ortowardstheamplifieronthe
amplifierend.Thismakesfindingthecorrectorientationmucheasier.
On/offswitch:
Theon/offswitchofeachamplifierisontherearofeachpowersupply,ontherightandside
(asviewedfromthefront.)
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DriverTubes:
FittheECC88andKT88DriverTubes.Besuretoensurethatthepinorientationiscorrectand
donotforcethem.TheKT88hasakeywayonthebaseandwillonlyfitoneway.Linethekey
onthetubewiththeslotinthetubesocket.Donotrockthetubeexcessivelyinthesocketto

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fitorremoveit,astheguideisBakeliteandiseasilybrokenoff.Thiswillnotaffectthe
operationofthetube,butitmakesfittingdifficult,andifthetubeisfittedincorrectly,amplifier
damagewilloccur.
ConnecttheamplifiertoyourHiFiSystem.Ifindoubtastowhethertousethe4or8ohmtaps
ontheamplifier,startwiththe8ohm.Justbecauseaspeakerisratedat4,6or8ohmsdoes
notnecessarilymeanthatistheloadseenbytheamplifierwhenplayingmusic.Whenthe
amplifierhasbeenbiasedandiswarm,listentosomemusicandthenconnecttothe4ohm
tapsandlistentothesamepieceagain.Theonethatsoundsfuller,strongerandmoremusical
isthecorrectsetting.Havingitontheincorrecttapswillnotdamagethespeakersorthe
amplifier.
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Biasing:Thebiasingontheamplifierwasreducedpriortoshippingasasafetymeasure.
Oncetheamplifierhasbeenonforawhileandisfairlywarm,connectaMultimetertothered
andblackbiasingterminalsontherightsideoftheamplifier.(Asseenfromthefront).
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SettheMeteronDCVolts,andadjustthescrew
betweenthetwoplugsuntilitreads2.2V.
Repeatontheotheramplifier.
Afteraboutamonthormoreofrunning,or
about200hours,checkandresetthebias.After
this,thereisnorealneedtokeepcheckingit,
unlessthetubeisreplaced,asthebiaswill
naturallydriftasthetubeages.
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Theseamplifiersgiveoffquitealotofheat,sopleaseensurethateachonehasadequate
ventilation
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Warranty:
ThewarrantyonallAM productsistwoyearspartsandlabor.Theamplifiermustbereturned
tothefactory,ortothedealerfromwhichitwaspurchased,ortoarepairerauthorizedbythe
factoryorthedealer.Thewarrantyontubesis3monthsfrompurchase.Ifatubelasts3
months,thenitismostlikelytolastthenormallifecycle.

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Pleasecontactyourdealerifyouhaveanyotherquestionsorifyouwouldlikeanyinformation
onother AM products.
AMwishesyoumanyyearsofveryhappylistening.Thankyou.
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Dataspecifications:
PowerTube833
TubecomplementECC88asthedrivers,KT88astheamplifiers.833
Frequencyresponse20Hz‐100KHz
InputImpedance100kohms
Inputsensitivity1.0Vrms
S/N >98dB
Inputselections RCAsingle‐ended;balanced/XLR
PowerOutput 120w
Loadimpedance 4&8ohms
Powerconsumption400W(each)
Powersupply100,110,120,220,230,240VAC50‐60Hz
Dimensions(W*D*H)amplifier340X450X292(mm)‐powersupply340X450X200(mm)
Weightamplifier30.7kgx2.powersupply44.7kgx2...
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