SonicFarmProAudio,Vancouver,BC,CanadaTel310-402-2390,778-863-1613www.sonicfarm.comforemail,pleaseusecontactboxonourwebsite

SonicFarmXcalibur/XcaliburJC

PentodePreamplifierandSaturator

USERMANUAL

DearAudioProfessional,ThankyouforpurchasingtheXcalibur.Wehopeitwilldeliverexceptionalrecordingsformanyyearsintothefuture.Pleasetakethetimetoreadthismanual.ItdescribesXcalibur’sdesignphilosophyaswellasitsmostimportantfunctions.DESIGNPHILOSOPHYSeveralyearsafterlaunchingourCreamerandBerlinertubepreamps,anideaarosetobuildsomethingspecial,apreampthatcouldsoundbothpristinecleanbutcouldalsobepushed“overtheedge”toaddsomegritwhenitwasneededtohelpotherwisepailtrackscutthroughthemix.Intoday’smodernmusicproduction,theboundariesbetween“normal”and“twisted”areincreasinglygettingblurred.Backinthe60’s,whentheBeatlesrecordedtheWhiteAlbum,GeorgeMartinusedalotofdistortionontrackstobreatheanewlifeintothosesongs.TheRedd47preampsbuiltintothemixingconsoleyieldedtheguitarfuzzonthe“Revolution”.Butbytoday’sstandardsthosesoundsarewaytoothinandpiercing.Wewantedtomakeapreampwithasmoothandcreamyoverdrivethatcouldbetailoredtosuitdifferentinstrumentsandthenblendedinwiththecleansignalinthepreciseamountneeded.IthadtosoundmoreorganicthanthemanyDAWpluginsusedforthatsamepurpose.WedidalotofexperimentationandfinallycameupwithacombinationofapentodewithaFETtransistorthatmadethetubeclipinanevenmorepleasingway.Thus,Xcaliburwasborn.LiketheCreamer,Xcaliburisapentodepreampwithnofeedbackloop.ItusesthesameEF86tubes.ButunliketheCreamerthathas2tubemodes,italwaysworksinthepentodemode.BecausethetubebiascircuitisdifferentthantheCreamer’s,itallowsfora3+1=4switchedgainsettings(thisisexplainedabitlaterinthismanual).Thisfirststageprovidescleangainonly,butevenifit’soverdriven,itstillclipsverygraduallytoavoidanyharshness.Ingeneral,Xcalibur’scleansoundisalmostidenticaltoCreamer’spentodemodetone.“Almost”,becauseduetoadifferentbiasingcircuitXcalibursrunonaneffectivelyhigherplatevoltage(320V)thanCreamers(285V),sothere’smaybeatadmore“juice”.Afterpassingthroughanadjustablehighpassfilter,thesignalisappliedtothesecondtubetooverdriveittotheleveldependentonthe“drive”controlsetting.Finally,the“OD”controlblendsthisharmonicallysaturatedsignalbackwiththecleanone.TheimportanceoftheODfilter,however,cannotbeoveremphasized:whensetcorrectly,itcanyieldawholerangeofusefulsaturation,fromathickvocalthatnoonewouldsuspectcontainsdistortiontotrashypsychedelicdrumsandgrindingbass.Ormikedguitarcabstreatedforamorerefinedoverdrive.Youcaninfactrunyourstereobussesthroughit,drumtracksoreventhemainmix.XcaliburusesthesameoversizedCinemagtransformerastheCreamer.Theinstrumentinputgoesdirectlytothetube,whereitseesaninputimpedancesimilartothatofatubeguitarorbassamp.TheoutputmodeontheXcaliburcan,likewithallofourpreamps,beswitchedbetweensolid-statebalancedandtransformer-driven.

ThestandardoutputtransformerhasaNi-Fealloycore,butXcaliburcanbealsoorderedwith100%Fetransformers.Thosecanevenbecombinedonthe2channels.Thetransformerwillimpartmore“weight”tothesignalwhendesired,asopposedtothetransparencyandhigherdefinitionofthesolidstatemode.(Tip:Ifyoupreferasofterhighend,trya100%Feoutputtransformer.)TheXcaliburJCwasintroducedinearly2018incollaborationwithJoeChiccarelli,aLosAngelesbasedproducer/engineer.HewascheckingouttheoriginalXcaliburathisSunsetStudioinHollywoodandrequestedafewmodstomaketheunitmoresuitableforhiswayofwork:Amasterpotreplacesthe3-wayattenuatorswitch,ODgain(markedOD+)nowhas3stages(mid/low/high),andthere’sanadditional3-pospost-driveLowPassfilter(markedODf2)SOMEREMINDERSREGARDINGTUBESTubesworkwithveryhighsupplyvoltages.TherearepointsinsideXcaliburthatmeasureinexcessof350VDC.Iftouched,thosevoltagescouldbelethal!Makesurethatnopointedobjects(especiallymetal)orliquidspenetratetheinsideoftheunitthroughitscoolinggrillesorotherwise.Ifthataccidentallyoccurs,immediatelypulltheplugoutofthepowersocketandwaitfortheunittodischarge.Xcaliburmustnotbeoperatedifmoisturepenetratesinside.Beforeopeningtheunit(tochangetube,wipeoffmoisture,etc)onemustdisconnectthemainscordandthenwaitseveralminutesfortheinternalcapacitorstodischarge.Whenmountinginarackenclosure,alwaysleaveanemptyspaceabovetheXcaliburtoensurepropercooling.Pleasedonotreplacethemainsfusewithoneofahighervalue:useonly600mA@115V(500mAalsoworksfine)(250to300mA@220-240V)LegalDisclaimer:NeitherSonicFarmnoranybodyassociatedwithitcantakeanyliabilityfordamagetopersonsorpropertycausedbyeitheruse,modificationorservicingthisunit.HOWTOCHANGETUBESThisonlyappliestoafunctionalunit.Pleaseentrustanyrepairstoqualifiedservicepersonnel.OnlyanEF-86(orequivalent,like6267,6CF8orRussian6J32P)pentodecanbeused.Pulloutthepowercord.Waitforatleast10minutesforallthecapacitorstodischarge.RemoveXcalibur’scoverbylooseningscrewsencircledredandmarkedwithanasterisk(3ontherearpanelandoneonthefrontone)aswellasallsidescrews(4M4screwsoneitherside).Youwillneedanallenwrench(somemodelswillhavePhillipsscrews).WhilepressingontheedgeoftheverticalPCboard(theonecontainingtubes)withonehand,pulloutthetubewithyourotherone.Small,butfastforward-reversemotionmaybeneededtoloosenthetubefromatightsocket.Donotbendthetubemuchoutoftheaxisbecauseyoucanbreakthepinsorcauseairtoenterthetubeanddestroyit.Payingattentiontothepinalignment,pushthereplacementtubeintothesocketusingsamemotionsbutintheoppositedirection.Makesureitgoesinalltheway.Duetoelectricshockdanger,testingthepreampwiththelidremovedisnotrecommended.Screwthecoverbackinplaceandyou’redone.

XCALIBUR’SFRONTPANELCONTROLS

XCALIBURJC:

1Phantompowerswitchwiththecorrespondinglight.Xcalibur’ssoftphantomcircuiteliminatestheannoyingaudible“crack”withMOSTmicrophones.However,someraremicrophones,duetotheircircuitdesign,willstillcausealoudpopafewsecondsAFTERthephantomvoltageisswitchedoff.Withthose,youwillstillneedtomuteorloweryourmonitoringlevel.2Inputattenuation15dBpad,pre-transformer.Alsolowersmicinputimpedance.31/4-inchunbalancedinstrumentinput.Goodforguitar,bassorkeyboards.Theinputimpedanceis2.2MΩ.4Line/Instrumentinputselector:pushintoactivatethelineorinstrumentinput.XcaliburhasadedicatedLineinputwithaseparate1:1transformer.Greattoinsertintoamasterbuss(oranyindividualtrack)fortonalcoloration.Withnothingpluggedintothefrontpanel¼”jack,therearpanelXLRlineinputswillbeactive.Tousetheinstrumentinput,simplyinserta¼plugintothefrontpaneljackwiththisswitchpushedin.Don’tcrankupthegainandMasteroutputinlinemodewithnothingconnectedinthebackorfront,youwillgetfeedback.5PoweronblueLEDindicator.6Drivecontroltocontrolthedistortionintensityofthesecondtube.TheOD+switchwillalsoinfluencethedrivegain(see9/9a).An“advanced”useofthiscontrolwhenrecordingclean:withtheBlendcontrol(8)atzero,Clean(18)adjustedasneeded,andtheairswitch(15)inthemiddle(off),tryturninguptheDrivecontrol(6).Althoughtheoreticallynothingshouldchange,becauseofthecapacitiveleakagebetweenthestages,onecanhearasubtleboostofextremelyhighfrequencies(“air”).Infact,thissoundsreallycoolonvocalsandsomeotherstuff.Tryit!TheOD+switchshouldbeout(Xcaliburstandard)ortotheleft(JC).7Bi-colorLED(green/red)signalpresence/overloadindicator.Redindicatesclippingdistortion.Toeliminateit,makesurethe“FAT”switchisnotintheright(gainmaxed)position,and/orreducethegainusingthegainswitch.Thelastresortisthepad.8Overdrive(OD)blendlevel.Thissignalissummedtogetherwiththecleanone(seecontrol18)toconstitutetheoutputsignal.Don’tturntheODBlendtoohighhopingtogetanadditional,pre-Masterleveloverdrive.Itwon’tsoundnice.Letthetubesdothesaturationwork.9(Xcaliburstandard)Pushthisswitchtoengagethesecond,FETbasedoverdrivestage,formoresaturationandharmonics.It’sagoodideatoreducetheODblend(8)firstbecausetheloudnesswillgoupquiteabit.9a(XcaliburJC)3positionoverdrivegainswitch:mid(left),low(middle)andhigh(right).Again,usetogetherwith(8).10Outputselect:low-distortionsolid-stateICortransformer.Solid-statemodewillsoundsomewhatcleaner,andthetransformerrounderandfatter.Xcalibur“A”hasNi/Fe(50/50),andXcalibur“B”100%Fetransformers.Bsoundsmorevintage.11Phasereverse(attheveryoutputofthepreamp).Affectsmic,lineandinstrumentinputs.12Channelcascadeswitch.Whenpushedtotheright,itroutsthefirstchannel’soutputintothesecondchannel’slineinput.Bothoutputsontherearpanelwillstillbeactive.Inordertocombinethesaturationsofbothchannels,the2ndchannelobviouslyneedstobeinlinemode.Beverymindfulofthegainstructurewhendoingthis,asthelevelsquicklygetveryhigh.Butsometimes,thiskindofanextremesetupiswhat

yourtrackrequires.(hint:forflexibility,keepch1clean,engagethecascadeswitchandrunch2inODonly,noclean.RecordbothoutputstoseparatetracksandlaterinthemixblendinasmuchdirtasyouwantwithinyourDAW).13Fatshelvingpresetboostandgainmaxswitch.Leftposition(Fat):Lowfrequencyshelvingbooststartingat300to1000Hz,dependingonthegainswitch(16)settingwithlowergaincorrespondingtohighercornerfrequencyandconsequentlymorebassboost.Thisfilterdoesnotuseaseparatestage;rather,itutilizesthecleantubegainstage.Theboostlevelcanbeadjustedbytheleftofthe2trim-pots,accessiblefromthetoplid,betweentheboostswitchesandaboutaninchinfromthefrontpanel(14,markedbyaredpointer).Themaximumboostyoucangetalsodependsonthegainswitch:thelowerthegain,themorebassboostisavailable,uptoabout12dB.6dB/octaveslope.Lowboostusesarealinductorforafattone.Midpositionisflat.RightpositionmaxesthepreampgainanddefeatsboththeFatandAirfilters.14Trimpots,accessiblethroughthecover,canbeusedtoadjusttheamountof“Fat”and“Air”boost.Useaminislot(.098”/2.5mmØ,.031”/0.8mmwide)orhex(.104”/2.64mmhexx.055”/1.4mmdeep)screwdrivertoadjustpots.15LeftandRightposition:Highfrequencyshelvingbooststartingat1to8kHz,dependingonthegainswitchsettingwithlowergaincorrespondingtolowercornerfrequencyandconsequentlymoretrebleboost.Theleftpositionhasthecornerfrequencylowerbyabout1.5octavesvs.therightone.Thisfilteralsoactsatthecleantubegainstage.Usetherighttrimpottoadjusttheboost(see14).Thisfunctionalsoalsointeractswiththegainswitch:thelowerthegain,themore“Air”boostisavailable,uptoabout12dB.6dB/octave.Midpositionisflat.

16Cleantubegaincontrolswitch.3positions:Lo,MidandHigh.When“High”isnotenough,maxthegainbypushingswitch(13)totheright.17Microphoneinputimpedance.Thelowertheimpedance,themoreofaloadwillthepreampinputpresenttothemicrophone.Standardvalueswillbe10kΩforthemiddleposition(HI),900Ωfortheleft(LO)and2400Ωfortheright(MED).The“PAD”switchwillalsoinfluencetheresultantmicinputimpedancevalue.Changinginputimpedanceismorelikelytoinfluencethetoneofdynamicmics,tosomedegreeribbons,andtoalesserdegreeornotatallcondensers.Lowerimpedancevalueswillrolloffsomehighend.18Cleanoutputlevel.ThesumofcleanandODblenddoesnotaffecttubegainorsaturation,justdetermineshowhardtheoutputbuffer,transformer,andultimatelytheloadisdriven.TheXcaliburmaydriveyournextunit(Compressor,EQ,Converter,Mixer)intoclippingeventhoughtheredlightdoesn’tindicateanydistortion.Inthatcase,reduceXcalibur’soutputlevel(cleanandODproportionally).Attenuationswitch(21)(orthemasterlevelcontrol21aforJC)canbeusedforthispurpose.19(markedHPf1fortheJCversion)High-passfiltercutofffrequency.160Hz(pos.1)or80Hz(pos.2),6dB/octave.Affectscleansignalonly.20(markedODf1forXcaliburJC)ODf/ODf1isapre-overdrivestagehighpassfilterthatcanbehandywhentoomuchbassorlowmidshittheODtubeandcreatemud.Youcanthenrollofftheundesiredbassormidswiththis6dB/octavemildslopefilter.Thepositionsare:fullon(left);bassandlowmidsrolledoff(middle)andonlybassrolledoff(right).Trythecenterpositionwhenyouonlywanttoaddpresencetothevocals,snaredrum,evenbassguitar.Experimentationisthebestapproachhere.

20a(JCversiononly)ODf2isapost-drive,pre-blendlowpassfilter.3positions:5.5kHz,12dB/octave(left);18kHz(middle)and1kHz,6dB/octave(right).Thefirstpositioncanbeusedtorolloffbuzzydistortionthatcanoccurwhenprocessingsomesignals.Themiddleoneisvirtuallyabypass.Therightpositionisusefulwhenblendinginsomesaturationtomakesomethingsoundbiggerandfatterbutwithoutdistortionbeingtooapparent.21Thisswitch(XcaliburStandardonly)attenuatesthefinaloutputmix(cleanplusOD).Itwillbeusefulwhenworkingwithhotsignalstoavoidclippingthenextprocessorinchain(likecompressor,EQorA/Dconverter).Thesettingsare:-6dB(left),0dB(middle)and-12dB(right).21a(XcaliburJC)Masteroutputlevelpot,postblend.Keepthiscontrolfairlyhigh,justshortofoverloadingyournextunitorinterface.22Powerswitch.XCALIBUR’SREARPANELCONTROLS:

23ACpowerreceptacle.Alwaysoperatetheunitonthemainsvoltageitwassetfor(110-120VACor220-240VAC,50-60Hz).Slidetheoperatingvoltageselectorswitch(23a)totherightfor110-120VAC(theleftsideoftheredswitchbodywillthenread110V),ortotheleftfor220-240VAC(therightsideoftheredswitchbodywillshow220V).Wrongvoltagesettingcancausealotofdamagetotheunit.24Mainsfuse.Pleasereplaceitonlywiththeoneofvalueindicated.(600mA@115VAC,300mA@220-240VAC)

25Groundliftswitch.Itshouldnormallybekeptin“GndOn”position.However,ifyouencounterhumwhentheunitispatchedintoyoursystem,switchitoverto“GndLift”.Thiswillremovehumduetogroundloopsonly;itwillnothelpeliminatehumthatcomesinwiththesignal!Donotdisconnectthegroundwireonyour3-prongmainsplug!

26and27Outputs.Balancedconnectiononly!(XLRpinconnection:1=GND,2=HOT,3=COLD).28and29Linelevelinputs.Balancedconnectiononly!(XLRpinconnection:1=GND,2=HOT,3=COLD)30and31Microphoneinputs.Balancedconnectiononly!(XLRpinconnection:1=GND,2=HOT,3=COLD)

TECHNICALSPECIFICATIONS:2channelsVariableinputimpedance(formicinputonly)Frequencyresponse:10Hz-50kHz+/-3dBMaximumcleangain:68dB(mic),48dB(inst.Andline)Harmonicdistortion(withnoODblend):<2%beforeclippinglevel,quicklydecreasesifdrivenless.Maximumoutputlevel:32dBuMinimumoutputload:600ΩConnectors:XLR’sformic,lineandoutput,balancedonlyInstrumentinput:1/4”unbalanced,monoPowerconsumption:30WWARRANTYINFORMATIONSonicFarmgivesaone-yearwarrantyonpartsandlaborfromthedateofpurchase.Shouldyouneedtosendinyourunitforwarrantycoveredservice,pleasecontactusforanRMAnumberfirst.Wewillalsotellyouwheretosendtheunit.AnyModificationoftheunitvoidsthewarranty.CONTACTINFORMATION:

SonicFarmProAudio,Vancouver,BC,CanadaTel310-402-2390,778-863-1613www.sonicfarm.comForemail,pleaseusecontactboxonourwebsite