Studio-Pro manual

VERSION 061411
Written & produced by the staff of
9167IndependenceAve.
Chatsworth,CA91311
(818)998-7791•FAX:(818)998-7835
Skype:paul.patroneteorpatrick.selfridge
www.MercuryMagnetics.com
[email protected]
Circuitry design by Alan Cyr
(www.Amp-Exchange.com)
Ifyoudonotknowhowtoreadaschematic,westronglyrecommend
thatyoutakethisprojecttoaqualifiedtechnicianforinstallation.
AllMercury Magneticsproductsare100%handmadebyusinCalifornia,USA.
Copyright©2009–2011byMercury Magnetics.AllRightsReserved.Mercury Magnetics,Mini-Choke,Studio-ProUpgrade
Kit,and“TheHeart&SoulofYourAmp”sloganaretrademarkslicencedtoMercury Magnetics.AxiomandToneCloneare
registeredtrademarkslicensedtoMercury Magnetics.VOXandAC4TVaretrademarksofVOXAmplification.Mercury
MagneticsisnotaffiliatedwithVOXAmplification.Thisprojectanditsdocumentationistheresultoftechnicalinvestigationsmade
bytheengineeringstaffofMercury Magnetics.Thedisclosureoftheinformationhereinmaypertaintoproprietaryrightsandthe
furnishingofthesedocumentsdoesnotconstituteanexpresedorimpliedlicensetousesuchmaterials.
Mercury MagneticsproductsareUL(UnderwritersLaboratoriesInc.)recognizedcomponentsfortheUSAandCanada.OBJY2
componentsystems,electricalinsulation,E120568.ULRecognition,class130(b)–Class200(n).OBJY8componentsystems,
electricalinsulation,certifiedforCanada,class130(b)–Class200(n).
Mercury MagneticstransformersandotherproductsareincompliancewiththeEuropeanUnionRoHSDirective2020/95/ECwith
respecttothefollowingsubstances:lead(Pb),mercury(Hg),cadmium(Cd,hexavalentchromium(CR(VI)),polybrominatedbiphenyls
(PBB),andpolybrominateddiphenylethers(PBDE).
Attention: Modifying your VOX AC4TV amp voids the VOX warranty!
2
VOX AC4tv•Mercury Studio-Pro Upgrade Kit
ThisprojectanditsdocumentationistheresultoftechnicalinvestigationsmadebytheengineeringstaffofMercury Magnetics.Thedisclosureoftheinformationhereinmaypertaintoproprietaryrightsand
thefurnishingofthesedocumentsdoesnotconstituteanexpresedorimpliedlicensetousesuchmaterials.
Introduction to the VOX AC4tv Studio-Pro Upgrade Kit
Congratulations!Andthankyouforinvestingin
theMercuryStudio-Pro Upgrade Kitforyour
VOX AC4tv.You’regoingtolovetheToneofyour
Upgradedamp.
About Upgrading your AC4tv
biddertransformersonlygiveyoulow-biddertone.
Manufacturersmaybestuckwiththisdilemmabut
youdon’thavetobe.MercuryhasTHEsolution
withournocompromiseUpgradetransformer
designs.Thesameyou’llfindinthebestproand
studioampsallovertheworld.
Don’tletyourVOXAC4tvamp’scompactsize
andpricefoolyou.Asidefromamazingtone,your
UpgradedAC4tvwillrunbothstudio-quietand
pedal-friendly.
Thebottomlineisthatnomatterhowanamp
plays,itcannotachieveitsfullsonicpotential
withoutfollowingthetime-testedrecipesof properly
engineeredtransformers.
Mercuryiswellconnectedwithbothproandstudio
players,andlongbeforetheUpgradedlittleamp
wasreadyforprime-timetheprototypesweremaking
theroundshereinLosAngeles.
Considerthattheseplayers
havethechoiceofanygearthey
want–butthey’rerunningwith
theUpgradedAC4tvbecause
theylovethewayitsoundsand
responds.Theyknowit’sbesttool
forthejob!
Qualitytransformersareagoodinvestment
becauseyou’regettingsomuchmoretone(and
ampreliability)foryourmoney.Usuallymakingthe
differencebetweenanampyou
loveandareinspiredtoplayvs.
onethat’sorphanedinyourcloset.
You’llfindthatyourUpgraded
AC4tvmaybeoneofthe
mostpedal-friendlylittleamps
you’lleverown.Sogoahead,
unmothballthosestompboxes,
experimentanddiscoverwhatnewdirectionsyou
cantakeyoursound.
Upgrade transformers and your tone
Savvyguitaristsandamptechsknowthattube
ampdesignbeginswithqualitytransformers.The
transformersyouusedetermineyouramp’stone.
Whenyougetthetransformersrightyou’reonthe
roadtoagreat-soundingamp.
However,thesedaysampmanufacturersareoften
forcedintoabalancingactofcompromisesinorder
tomeetthelowbudgetdemandsofthemarket.First
onthehatchetlististhetransformers.Andsadly,low-
Why’s that?
Oneofthemostsignificant(and
notsoobvious)reasonswedon’t
likethesoundofsomeampsisa
phenomenonknownas“earfatigue.”
Innatureallsoundsare
composedoflayersoffrequencies
producingallsortsofharmonics
anddistortion.Ear fatigueis
causedbyinformationcomminglingwithnonmusical,unnaturalnoisethatbeatupyourinternal
mechanisms–someofwhichwe“feel”morethan
hear.Thesemechanismsendupworkingovertime
tryingtoseparatethedesirablefromtheless
desirablesounds.That’showfatiguehappens.
Apopularmisconceptionisthatvacuumtubeswere
designedtodistort.Weonlyenjoythebenefitsof
distortionbytheinfluenceoftheamp’stransformers
– not its tubes.Whenit’sdonerightyouheartone
that’smoremusical,appealing,andless fatiguing.
Tonethattakesyouin,invitesandinspires
Continued on next page è
VOX AC4tv•Mercury Studio-Pro Upgrade Kit
3
ThisprojectanditsdocumentationistheresultoftechnicalinvestigationsmadebytheengineeringstaffofMercury Magnetics.Thedisclosureoftheinformationhereinmaypertaintoproprietaryrightsand
thefurnishingofthesedocumentsdoesnotconstituteanexpresedorimpliedlicensetousesuchmaterials.
moreplaying.Tonethatgivesyouanemotional
experience.It’sallaboutmusicalitythat’svirtually
impossiblewithouttherighttransformers.
spectrumofthosewishingtomaketheUpgrade.
Thephotosandillustrationsinthismanualwill
minimizeguessworkorinterpretationissues.
Kick-starting your tone
There’salottobesaidaboutrollingyourown,but
ifyouhavea caseoftinkerituswerecommend
thatyouinstalltheUpgradeasdocumentedhere
–doitfirst–beforeconsidering orexperimenting
withanyothermodification.Inthiswayyou’llhave
agoodtonalreferenceforothermodsyoumay
choosetomake.
There’snoshort-cuttobuildingqualitytransformers.
That’swhyMercuryplayssuchanimportant
roleinyourmusic.Weprovideyouwiththekey
componentsinthechainbetweenyourguitar
andtheear.But,wecanonlygettherewith
uncompromisingengineeringexpertise,the
uncommonlyhighqualityofourmaterials,our
uniqueandproprietary“recipes,”andcraftsmanship
unlikeanywhereelseintheworld.
Itcostsalotmoretoproducezero-compromise
transformers.Buttheresultisthatmusicians
everywheretellushowmuchtheyloveour
products.Webelievethatwhenyou’veheardhow
Mercurytransformerscanimproveyoursound,
you’llbehooked,too.
Using this Upgrade Kit
Besuretoreadthroughthisentiremanualbefore
beginningtomodifyyouramp.Ifyouarenot
comfortableorunsureinanyway,werecommend
thatyoutakeyourKitandamptoaqualified
Mercuryinstaller.Foranamptechnearyou,
pleasecall,Skype (a popular web-based telephone
service),writeoremailusforareferral(worldwide).
Workingonanyelectronicdeviceispotentially
hazardous.ToperformthisUpgradeyoushould
haveatleastcompletedabasicelectronicsassembly
class,orknowsomeonewhocansafelyguideyou.
It’s easytodamageyouramp.Whilemostthingsare
repairablethe“learningexperience”couldcostyou.
Thatsaid,we’veattemptedtobreakthismanual
downintoaseriesofeasy-to-follow,sequentialsteps
–almost“paint-by-number.”We’reawarethatthis
stylemayputoffsomeonewithold-schooltraining,
butourintentionistohelpthebroadestpossible
TheUpgraderequiresaradicalmodificationof
youramp’smainPCB(printedcircuitboard),
replacingthepowerandoutput transformers,with
theadditionofaMercury“Mini-Choke.”Our
Mini-Chokereplacesaresistorontheoriginal
PCBandaddsanoticeableamountofdynamic
headroom(WOW!factor)tothecircuit.
Notethatallampsofthistypearedividedinto
threesections:powersupply,preampandpower
amp.Learningaboutandunderstandingthese
fundamentalprinciples,alongwithhowtheamp’s
transformersandchokeinteract,willtakeyoualong
waytowringingthemostfromanytube-basedamp.
Your feedback
Wouldyouliketohelpusmakeevenbetter
Upgrade Kitsinthefuture?Or,wouldyouliketo
shareyourideas, experiencesorperhapsasound
cliporYoutube?YourfriendsatMercurycare
aboutwhatyouhavetosay,andwelcomeyour
feedbackandcontributionstothisproject.
Sendcomments,suggestions,video,relevant
links,photosandsoundsamplesto:
[email protected]
orcallusat(818) 998-7791
OnbehalfofthestaffofMercury Magnetics,
thankyouagainforputtingyourtrustinus.
O
You’ve made the Mercury Upgrade – now you’re ready to play!
4
VOX AC4tv•Mercury Studio-Pro Upgrade Kit
ThisprojectanditsdocumentationistheresultoftechnicalinvestigationsmadebytheengineeringstaffofMercury Magnetics.Thedisclosureoftheinformationhereinmaypertaintoproprietaryrightsand
thefurnishingofthesedocumentsdoesnotconstituteanexpresedorimpliedlicensetousesuchmaterials.
Table of Contents
Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 3
PartsList. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
WiringSchematicsandTransformerDiagrams. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
TransformerandMini-Chokespecificationsheets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
AWalk-ThroughtheUpgradeProcess. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 14
Appendices:
UsingaVariac&CurrentMeter. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
Tips’nTricksforWorkingonPCBs. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 40
AbouttheFilamentLeads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
TheOutputTransformerCircuit. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43
DischargingFilter Capacitors. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
CelestionGold(G10)10”speakerspecifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
CAUTION!Thevoltagesinyouramplifiercanbedangerous.Transformersandchokesarenotuser
servicableparts.Installationofthesecomponentsshouldalwaysbeperformedbyanexperiencedtechnician.Thesimpleabilitytouseasolderingironisnotenoughtoqualifya“do-it-yourselfperson.”Those
whoareinexperiencedinworkingwithelectroniccircuitsshouldneverattempttoservicetheiramplifiers.Householdlinecurrentscanbedeadly!!Transformers,chokesandlargefiltercapacitorscanstore
dangerouscharges forseveraldays,orlonger,aftertheamplifierhasbeenunplugged.Nevertouchthe
terminalsofthesecomponentswithoutbeingcertainoftheirchargestatus.Riskofshockanddamageto
equipmentmayresultfrom mishandlingand/orimproperuseofthesecomponents.Pleaseusecommon
senseandalwaysthinksafetyfirst.Afterall,greattoneismostenjoyedwhenyouarealivetohearit.
SOLDERING NOTE:VOX’s AC4tvisassembledusingRoHScompliant,lead-freesolder.Workingwithlead-freesolderisdifferent
thanstandardsolder.Generallyahotterironisnecessary.Formoreinformationwerecommenddoingaweb-earchfor“lead-free
solderingtechniques.”
PULL TEST:Afterreassembly,makesurethatalloftheclipconnectorsfromthetransformerstootherampcomponentsaresecure.To
besure,givetheclipsatugwithasetofneedlenosepliers.Ifaclipslipsoffrelativelyeasily,you’llneedtoreshapeorcrimpitsothatit’ll
holdsecurely.
DO NOT POWER UP THE AMP WITHOUT TUBES!
CAPACITOR DISCHARGE WARNING:Safedischargingoffiltercapacitorsmatters.Itisessentialforyoursafetyandtoprevent
damagetotheamp’scircuitry,thatlargeorhighvoltagecapacitorsbefullydischargedbeforemeasurementsaremade,solderingis
attempted,orthecircuitryistouchedinanyway.Forinformationonhowtodothis,web-search“capacitordischarging.”Alsoseethe
appendixforadditionalinformation.
CAPACITOR POLARITY:Notethatmanycapacitorshavepositiveandnegativepolarity,andarestampedaccordingly.Besurethat
theirpolarityiscorrectwhensolderingtoaPCB.
BRAIDING, TWISTING AND COILING LEADS:Donotbraid,twistorcoilthepowertransformer’sB+leadwire.Checkourreference
illustrationsandphotostoseewhichleadsaretwistedtogether.Typicallyonlythefilamentleadsofthepowertransformer.Otherpositioningofleadsmaybenecessarytominimizeampnoise.Followarediagramsandinstructsforoptimalperformance.
TRIMMING TRANSFORMER LEADS:Tominimizenoise,measureandtrimthesolderableleadlengthsofthetransformersandMiniChoke™.Routeallwirescleaningaroundthetubes,chassis,etc.
CLIPPING vs. UNSOLDERING PCB COMPONENTS:TomakethisUpgradeitwillbenecessarytoremoveseveralcomponentsfrom
theMainPCBoftheamp.Duetoqualityissueswithmodernoff-shorePCBmanufacturing,itcanbedifficulttounsolderanitemwithout
creatingotherproblems,themosttypicalofwhichisaneyeletdetachingfromthePCB.Thereforewe’veindicatedwhichcomponents
shouldbeclippedvs.unsoldered.Tounsolderheatyourironto800ºF,thenveryquicklyheatinguponesideoftheexistingsolderconnectionwhilepullingitthroughontheother.Iftheironisnothotenough,oryoulingertoolong,theeyeletwillgetdamaged(orfalloff).
Ifthishappensyou’llhavetofabricatearepair,orcreatedajumpertoatrace.Seethismanual’sappendicesfortips.
POWERING UP A GUITAR AMP:Aftermakinganymodificationstoanamp’scircuit(e.g.thisUpgrade)useaVariacalongwithan
currentmeter(somehaveboth)toslowlyapplypowertotheampwhilecheckingforwarningsignsofcircuitryerrorsorshorts.Seethe
sectionon“UsingaVariac”attheendofthismanual.
LOADING OUTPUT TRANSFORMERS:Youmustconnectaspeakerorspeakercabtoyourampbeforepoweringitup.Withouta
loadtheoutputtransformerwillblow.
MINI-CHOKE FACTOID:AMercuryMini-Choke™replacesaresistorandaddsadisernableamountoftonaldimensiontothecircuit.
TRANSFORMER BREAK IN PERIOD:Asageneralrule,transformersrequireapproximately30hoursofplaying time tobefully
brokenin.PleaserefertoMercury’swebsiteformoreinformation.
BE SAFE! ALWAYS USE PROTECTIVE EYEWEAR!
VOX AC4tv•Mercury Studio-Pro Upgrade Kit
5
ThisprojectanditsdocumentationistheresultoftechnicalinvestigationsmadebytheengineeringstaffofMercury Magnetics.Thedisclosureoftheinformationhereinmaypertaintoproprietaryrightsand
thefurnishingofthesedocumentsdoesnotconstituteanexpresedorimpliedlicensetousesuchmaterials.
Parts List
Transformers:
• MercuryAxiom120Vpowertransformer(part#:VXP-AC4-REREV.3)or . . . . . . . . . . . . . . . . . . . . . .
• MercuryAxiom240Vpowertransformer(part#:VXP-AC4-RE-240) . . . . . . . . . . . . . . . . . . . . . . . . . .
• MercuryAxiomoutputtransformer(part#:VXO-AC4-95). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
• MercuryAxiomMini-Choke™(part#:VXO-AC4-CH). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1
1
1
1
Power Diodes:
•IN4007(blackwithwhiteband) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
Capacitors:
•47mF(electrolytic/radial/35V85°C) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
•10mF(electrolytic/radial/50V85°C) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
•10mF(electrolytic/radial/350V85°C) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
•47mF(electrolytic/radial/350V85°C) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
•22mF(electrolytic/radial/350V85°C) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
•22mF(electrolytic/radial/25V85°C) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
•47rF(silvermica/500V). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
•680rF(silvermica/500V). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
•0.047mF(mylar/400V) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1
1
1
1
1
1
1
1
1
Resistors:
•2.7KW(1watt/metaloxide(flame-proof)/colorcode:red,violet,red). . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
•47KW(.5watt/carbonfilm/colorcode:yellow,violet,orange). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
•470W(.5watt/carbonfilm/colorcode:yellow,violet,brown). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
•470KW(.5watt/carbonfilm/colorcode:yellow,violet,yellow). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
•3.9KW(.5watt/carbonfilm/colorcode:orange,white,red). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
•15KW(.5watt/carbonfilm/colorcode:brown,green,orange). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
•2.2KW(.5watt/carbonfilm/colorcode:red,red,red) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
•68KW(.5watt/carbonfilm/colorcode:blue,grey,orange).....................................1
•100KW(.5watt/carbonfilm/colorcode:brown,black,yellow). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
•22KW(.25watt/carboncomp/colorcode:red,black,orange). . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Misc. Components:
•Audiotaperpotentiometer(A1M)replacementfor“Volume”control. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
•Coilofshieldedfilamentwire20gauge. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ~12"
•Coilofclearinsulationtubingspaghetti. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ~12"
•Coilofunshieldedfilamentwireforjumpers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ~12"
•Stand-offassembly. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
•Cableties–6" . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
•No.8–1/2"woodscrews(tomountMini-Choke) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
•InstructionalCD-ROM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
• Mercurymetalbadge. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
• Mercuryguitarcasesticker . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Recommended tools for this project:
• Goodqualitysolderiron(capableoftempsat>800ºF)
• Electronicsgradesolder
• Soldersuckerand/orwick
• Dremel Toolwith1/16"bit,reamerandsmallgrinder*
• Setofscrewdrivers(Philips)
• ExactoknifeforcuttingandscrapingPCBtraces*
*Dremel ToolcanbeusedtocuttracesanddrillholesinPCB.
6
VOX AC4tv•Mercury Studio-Pro Upgrade Kit
• Smallneedle-noseplyers
• Wirestrippers
• Loctite 290(green)
• PureisopropylalcoholandQ-tips
• Variacandcurrentmeter
ThisprojectanditsdocumentationistheresultoftechnicalinvestigationsmadebytheengineeringstaffofMercury Magnetics.Thedisclosureoftheinformationhereinmaypertaintoproprietaryrightsand
thefurnishingofthesedocumentsdoesnotconstituteanexpresedorimpliedlicensetousesuchmaterials.
Power
Transformer
VXO-AC4-95
VXP-AC4-RE REV. 3 (120V) or
VXP-AC4-RE-240 (240V)
Output
Transformer
RESISTORS (carbon film)
1x
1x
1x
1x
1x
1x
1x
1x
CAPACITORS (electrolytic)
470Ω 1/2W
(yellow/violet/brown/gold)
47KΩ 1/2W
(yellow/violet/orange/gold)
470KΩ 1/2W
(yellow/violet/yellow/gold)
2.2KΩ 1/2W
(red/red/red/gold)
1x
10µF 350V 85°C
1x
22µF 350V 85°C
1x
47µF 350V 85°C
1x
1x
1x
3.9KΩ 1/2W
(orange/white/red/gold)
15KΩ 1/2W
(brown/green/orange/gold)
68KΩ 1/2W
(blue/grey/orange/gold)
20KΩ 1/4W
(red/black/orange/gold)
2.7KΩ 1W
(red/violet/red/gold)
47µF 35V 85°C
47µF 35V 85°C
22µF 25V 85°C
22µF = 25V 85°C
10µF 50V 85°C
10µF = 50V 85°C
1x
2x
#8 – 1/2” wood screws
IN4007
(black with white band)
2x
47µF 350V 85°C
Stand-off kit
RESISTOR (metal oxide / flame proof)
POWER DIODE
22µF 350V 85°C
1x
RESISTORS (carbon composition)
1x
10µF 350V 85°C
Note that electroyltic capacitors have polarity.
Be sure to study the schematics for the correct
directions when Upgrading your amp.
100KΩ 1/2W
(brown/black/yellow/gold)
1x
Mini-Choke™
VXO-AC4-CH
CAPACITORS (silver mica)
1M audio taper
potentiometer
with nut and washer
1x
680ρF 500V
1x
5x Cable ties (6 in.)
47ρF 500V
Instructional CD ROM
Mercury metal nameplate
Mercury guitar case sticker
CAPACITOR (mylar)
1x
.047µF 400V
~12 in.
coil
~12 in.
20 gauge shielded wire
coil
Insulated wire “spaghetti”
~12 in.
coil
Unshielded filament wire
Version: 02-24-11
VOX AC4tv•Mercury Studio-Pro Upgrade Kit
7
ThisprojectanditsdocumentationistheresultoftechnicalinvestigationsmadebytheengineeringstaffofMercury Magnetics.Thedisclosureoftheinformationhereinmaypertaintoproprietaryrightsand
thefurnishingofthesedocumentsdoesnotconstituteanexpresedorimpliedlicensetousesuchmaterials.
8
VR-2
VOLUME - A500K
R-7 - 15Ω
R-13
15Ω
C-9
10µF
CT
R-14 - 5.6Ω
www.VoxAmps.com
C
JS-2
EXTERNAL SPEAKER
R-25 - 15Ω
C-5
4.7ηF - 100V
OUTPUT
TRANSFORMER
C-10
10µF
R-9
220K
Schematics for the
Stock AC4tv
A
R-1
220K
D
SW-1A
SWITCH
R-22
220K
R-21
5.6K
9
2
C-6
22ηF - 400V
16Ω
+
B
3
1
V-2B
12AX7
2
3
H
2K
R-5
220K
C-8
220µF - 63V
R-20
220K
C-20
22ρF - 500V
C-11
10µF
C-12
2.2ηF
H
R-8
1.5K
VR-1
TONE - A500K
R-18
2.2K
C-16
1µF - 50V
R-2
1M
C-1
22ρF - 50V
8
C-18
100ηF - 400V
-
V-1
EL84
7
R-15
3.9K
V-2A
12AX7
C-15
470ρF - 500V
6
7
R-12
1M
R-4
27K
C-4
220ρF - 500V
R-3
10K
C-3
.022µF - 400VDC
JS-1
INPUT JACK
FB-1
FERRITE BEAD
C-2
NF - 50V
2G
C
B
5
H
6
IP
H
7
3
8
2
2P
D
4
9
1
12AX7
IG
K
IK
G1
4
6
Ic
7
3
8
2
Ic
HT
5
9
1
EL84
P
Ic
G2
A
AC4TVH (Head)
R-16
470Ω
Q-3
1N4007
R-24
220Ω
POWER
TRANSFORMER
Q-2
1N4007
R-17
220Ω
CT
N
E
L
FS-2
T125mAL
250V
R-11
100Ω
R-6
560Ω
FS-4
FS-1
T6.3AL 250V
Q-1
1N4007
C-13
100µF - 350V
C-7
10µF - 350V
R-16
22K
C-17
10µF - 350V
R-23
22K
C-14
33µF - 350V
with
V112TV
Speaker Cabinet
R-10
100Ω
GROUNDING WASHER
VOX VERSION 1/ ISS2b / 03-13-09
VOX AC4tv•Mercury Studio-Pro Upgrade Kit
ThisprojectanditsdocumentationistheresultoftechnicalinvestigationsmadebytheengineeringstaffofMercury Magnetics.Thedisclosureoftheinformationhereinmaypertaintoproprietaryrightsand
thefurnishingofthesedocumentsdoesnotconstituteanexpresedorimpliedlicensetousesuchmaterials.
SW-1B
SWITCH
SW-7
POWER SWITCH
Schematics drawn and supplied by—
AC4TV Combo
Copyright © 2009–2010 by Mercury Magnetics. All Rights Reserved. VOX and AC4tv are trademarks of VOX Amplification Ltd. Mercury Magnetics and “The Heart & Soul of Your Amp,” are trademarks of Mercury Magnetics. Axiom is a registered trademark of Mercury Magnetics. Mercury Magnetics is not affiliated with VOX Amplification Ltd.
www.MercuryMagnetics.com
(818) 998-7791
VERSION: 05-13-10
9
2
3
H
H
R-5
220KΩ
2K
D
CHOKE
7
8
2
12AX7
H
IG
K
IK
G1
5
4
6
Ic
7
3
8
2
1
Ic
HT
R-24
IN4007
9
EL84
G2
Q-2
1N4007
R-17
IN4007
POWER
TRANSFORMER
CT
N
E
L
FS-4
FS-1
T6.3AL 250V
CT
FS-2
T125mAL
250V
10µF - 50V
47KΩ
35VDC
approx.
Q-3
1N4007
R-6
560Ω
C-13
47µF - 350V
C-14
22µF - 350V
C-17
10µF - 350V
C-7
10µF - 350V
9
1
Q-1
1N4007
2.7KΩ - 1W
470KΩ
3.9KΩ
IP
6
A
B
10µF - 350V
C
H
5
4
3
2P
R-23
~17KΩ
R-25 - 15Ω
+
B
2G
D
R-14 - 5.6Ω
R-7 - 15Ω
R-13
15Ω
C-9
10µF
C-10
10µF
680ρF - 500V
47µF - 35V
R-9
68KΩ
VR-1
TONE - A500K
V-2B
6 12AX7
-
V-1
EL84
7
VR-2
VOLUME - A1M (AUDIO)
R-2
1MΩ
7
22µF - 25V
8
JS-2
EXTERNAL SPEAKER
SW-1A
SWITCH
.047µF - 400V
3
+
V-2A
12AX7
4.7ηF - 50-100V
1
2
20KΩ
R-4
27KΩ
47ρF - 500V
JS-1
INPUT JACK
R-18
470Ω
Notes:
1. Unless otherwise stated
all resistors are carbon film
.5 (1/2) watt.
2. RED indicates modifications
to the original PCB circuit.
3. See accompanying parts list
for a more detailed specifications
of the new components.
OUTPUT
TRANSFORMER
R-22
100KΩ
For the VOX AC4tv PCB version 1 / ISS2b / 03-13-09
Mercury versions: 09-10-09 (original),
02-21-11 (current)
SW-1B
SWITCH
A
C
www.MercuryMagnetics.com
(818) 998-7791
GROUNDING WASHER
VOX AC4tv•Mercury Studio-Pro Upgrade Kit
To Filaments
SW-7
POWER SWITCH
To Filaments
Copyright © 2009–2011 by Mercury Magnetics. All Rights Reserved. VOX and AC4tv are trademarks of VOX Amplification Ltd. Mercury Magnetics, AC4tv Upgrade Kit and “The Heart & Soul of Your Amp” slogan are trademarks of Mercury Magnetics. Axiom is a registered trademark of Mercury Magnetics. Mercury Magnetics is not affiliated with VOX Amplification Ltd.
This project and its documentation is the result of technical investigations made by the engineering staff of Mercury Magnetics. The disclosure of the information herein may pertain to proprietary rights and the furnishing of these documents does not constitute an expressed or implied license to use such materials.
9
ThisprojectanditsdocumentationistheresultoftechnicalinvestigationsmadebytheengineeringstaffofMercury Magnetics.Thedisclosureoftheinformationhereinmaypertaintoproprietaryrightsand
thefurnishingofthesedocumentsdoesnotconstituteanexpresedorimpliedlicensetousesuchmaterials.
Schematics drawn and supplied by—
P
Ic
16Ω
VXP-AC4-RE
TM
Mercury Magnetics
9167 Independence Ave. • Chatsworth, CA 91311
(818) 998-7791 • FAX (818) 998-7835
[email protected] • www.MercuryMagnetics.com
100% of our products are designed & handmade in So. California, USA. • Established in 1954
120V Version
3”
2”
2-1/2”
2-1/2”
REV. 3
PRIMARY
SECONDARY
RED
0V
BLACK
Note: Black dots
indicate polarity—
start of winding
2-3/4”
1-5/16”
120V
SHIELD
WHITE
GREEN/
YELLOW
W H IT E
BL AC K
W HI TE
K
B L AC
EL
Y
N/
GR
RED
W HI TE
RN
D
/G
RE
TE
HI
W
W H IT E
RE D
BL AC K
RE D
B L AC K
L
/YE
GRN
BL AC K
(All dimensions are nominal)
W H IT E
WH
ITE
/GR
WHITE
N
W H IT E
Chatsworth, CA USA • www.MercuryMagnetics.com
BLACK
RED
257V
0V
B+
257V
WHITE
WHITE/GREEN CT
FILAMENT 6.3V
WHITE
LABEL
Note: Grounding of the Faraday
Shield is optional. It may reduce
noise depending upon the source
of the ground.
VXP-AC4-RE
REV. 3
RED
R ED
W HI TE
K
B L AC
EL
Y
/
N
GR
W HI TE
TE/G
WHI
TYPE: Power Transformer
MOUNTING: Horizontal Mount
CLASS: Axiom®
PART NO.: VXP-AC4-RE
ORIGINAL VOX
PART NO.: 076-AC4U
DATE: 01-27-11 (Rev. 3)
REV. 3
For upgrading the VOX AC4tv
combo or AC4tvH head
VXP-AC4-RE
RN
www.MercuryMagnetics.com
Made in Chatsworth, CA U.S.A.
The Mini-Choke was invented by Mercury Magnetics. Copyright © 2009–2011 by Mercury Magnetics. All Rights Reserved. Mercury Magnetics, Mini-Choke, AC4tv Mercury Upgrade Kit and “The Heart & Soul of Your Amp”
slogan are trademarks of Mercury Magnetics. Axiom is a registered trademark of Mercury Magnetics. VOX and AC4tv are trademarks of VOX Amplification Ltd. Mercury Magnetics is not affiliated with VOX Amplification Ltd.
10
VOX AC4tv•Mercury Studio-Pro Upgrade Kit
ThisprojectanditsdocumentationistheresultoftechnicalinvestigationsmadebytheengineeringstaffofMercury Magnetics.Thedisclosureoftheinformationhereinmaypertaintoproprietaryrightsand
thefurnishingofthesedocumentsdoesnotconstituteanexpresedorimpliedlicensetousesuchmaterials.