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Coda 07x FET Preamplifier User manual

  • Hello! I've reviewed the provided user manual for the CODA Preamplifier 07x. This document details the preamplifier's features, such as its balanced outputs, adjustable gain, and FET-based design. I am ready to answer your questions about the device's operation and specifications.
  • What are the main output connections on the 07x?
    How do I adjust the volume on the 07x?
    What does the BYPASS button do?
    How can I adjust the gain of each input?
OPERATION MANUAL
Preamplifier07x
CARE&HANDLING
WARRANTY REGISTRATION
WARRANTY & DISCLAIMER
3
6
9
8
4
INSTALLATION CONNECTIONS
DETAILED INSTALLATION
DESIGN PHILOSOPHY
10
TECHNICAL DATA
2
INTRODUCTION
11
1
SAFETY PRECAUTIONS
2
INTRODUCTION
1
SAFETY PRECAUTIONS
!
CAUTION
CAUTION
WARNING
WARNING
1
SAFETY PRECAUTIONS
CAUTION -
-
-
-
-
CAUTION: TOPREVENT ELECTRIC
SHOCK,DONOT REMOVECOVER.
NOUSERSERVICEABLEPARTS
INSIDE,REFERSERVICING TO
QUALIFIEDSERVICEPERSONNEL.
THISSYMBOL IS TO ALERT YOUOF
THEPRESENCEOFUNINSULATED
DANGEROUSVOLTAGEWITHIN THE
UNIT'SENCLOSURE THAT MAY BEOF
SUFFICIENT MAGNITUDE TO
CONSTITUTE A RISKOFELECTRIC
SHOCK.
THISSYMBOL ISINTENDED TO ALERT
YOUOF THEPRESENCEOF
IMPORTANT OPERATING AND
MAINTENANCEINSTRUCTIONSIN THE
LITERATURE ACCOMPANYING THE
UNIT.
WARNING:TOPREVENT FIREORSHOCKHAZARD,DO
NOT EXPOSE THISUNIT TORAINOR
MOISTURE. TO AVOIDELECTRICAL SHOCK,DO
NOT OPEN THEUNIT.REFERSERVICING TO
QUALIFIEDPERSONNEL.
Neverinstallorremovethepowercordfromthechassis
unlessithasbeendisconnectedfromthe ACpowersource
first.
Neverpullonthepowercordwhenremovingitfroman AC
powersource.Graspitbytheplug.
Donotleavethepowercordconnectedtoan ACpower
sourceunlessitisconnectedtotheunit.
Itisrecommendthatduringextendedperiodsofnon-use
thattheunitspowercordbeunpluggedfromits ACpower
source.
Routethe ACpowercordsothatitwillnotbedamagedor
walkedon.
!
2
INTRODUCTION
Thispreamplifierisaprecisiondevice,designedinanefforttoprovidethelistenerwith
unmatchedsoundquality,design,andconstruction.Inordertooperateyourpreamplifier
properlyandtorealizeallofthecapabilitiesofthe07XPREAMPLIFIERwerecommendthat
youreadthisentiremanualcarefully.
3
INSTALLATIONCONNECTIONS
Illustratedbelowistherearpanelofthe07X. Theconnectionsarestandardandtypicalofany
audiopreamplifier. Anyunknownfeaturesshouldbeadequatelyexplainedbythefunction
descriptionsonthefollowingpage.
Bothsetsofbalancedreceptaclesontheleftsideareidenticalstereooutputssuitablefor
connectiontomultipleamplifiers. Thetwosetsofbalancedreceptaclesontherightsideare
separateinputchannels.
Makesureduringinstallationthatthe ACpowerconnectionsareinterruptedtothe
preamplifierandallothercomponentsareoff.Whilethediagrammaybeselfexplanatory,we
stronglyrecommendthatyoureadthefrontpaneldescriptiononthefollowingpageforuse
instructions.
4
DETAILEDINSTALLATION
1. Thefirstfourbuttonsselecttheinputsource.
2. ThePROCESSORbuttonswitchesinanaudioprocessor(surroundsound,equalizer,etc.)
3. TheMONObuttoncombinestheleftandrightaudiochannels.
4. TheBYPASSbuttonwillcausethegaintodroptounity,bypassingthenormal12dB
standardgainofthe07x.
5.Volumeandbalancesettingisindicatedbythedecibel(dB)display.
FORVOLUME ADJUSTMENT: Thevolumedisplayshows"relative"volumelevel.Whenthe
displayreads"99"thereisnodecibelattenuation,"00"isthemaximumdecibelattenuation,
andlevelchangesoccurin1dBincrements.
FORBALANCE ADJUSTMENT:Inthewindownexttothenumberdisplayarethreeindicator
LEDs,MAIN,LEFT,andRIGHT.IntheMAINmode(blueLED)thedisplayreadoutshows
volumelevel.IntheLEFT mode(whiteLED)thedisplayreadoutshowsleftbalancelevel.In
theRIGHT mode(redLED)thedisplayreadoutshowsrightbalancelevel.Inadditionthe
displaywillflashonandowhenthevolumeismuted.
Whenadjustingindividualchannellevelforbalancingpurposes,thedisplayshows"actual"
decibellevel.Inotherwords,thedefaultvalueof"0"ontheLEFT orRIGHT channelmode,
showsthatthechannelisnotattenuated. A valueof"99"showsthechannelis-99dbbelow
fullvolume.
6. TheVOLUME/BALANCEiscontrolledbytheopticalencodercontrol.Clockwiserotation
increaseslevel,counterclockwiserotationdecreaseslevel.Leftbalanceisselectedby
pressingtheknobonce,andadjustingthelevel.Rightbalanceismadebypressingtheknob
again,andadjustingthelevel.Pressingtheknobonceagainwillbringitbacktobeinga
volumecontrol.
7. ToadjusttheGAINofeachinput(tomatchthelevelsofallthecomponentsinthesystem),
pressandholditsselectorbuttonwhileyoupressthevolumeknob-thenreleasethemboth.
Thedisplaywillswitchto"00"andtheselectedinputlightwillflash.
Turnthevolumeknobclockwisetoraisetheinputgainupto+18dborturncounterclockwise
toreducetheinputlevelupto-99db(notethatthesigns"-"or"+"arenotdisplayed).
ToswitchbacktoMAIN,pressanybuttonortheknob,orwaitfifteenseconds.
REMOTEOPERATION
The07xcanbeoperatedbyremotecontrol. TheMX-450LearningRemoteis
includedwiththeamplifier.ForinstructionsonusingtheMX-450itselfseethe
onscreenmanualincludedintheremote.
5
DETAILEDINSTALLATION
6
DESIGNPHILOSOPHY
ThecircuitryusedintheFET PREAMPLIFIER07xistheresultofanadvancedandcomplete
designprocesscombininginnovationandprovefundamentals. Thisprocessavoidsboththe
limitationsoftotaladherencetoconventionandtheflawsresultingfrominappropriate
applicationsofclevercircuitgimmicks.
ImpedanceisolationandmatchingisderivedfromFETs.Whilecarefuldesigncanyieldgood
resultsfromanydevicetype,FETsconsistentlyhavetheedgeinvoltagegain,lownoise,low
interaction,andinterfaceapplications.
FETsareinherentlytransconductancedevices,meaningthataninputvoltagecontrolsan
outputcurrent.Unlikeconventionaltransistors,FETshaveextremelyhighinputimpedance
(about10megohm-similartovacuumtubes). TheFET "senses"theaudiosignalwithout
drawingcurrentfromthesource. Thiseliminatescomplexinteractionswiththesource,allows
maximumperformancefromeachsystemelement,andgreatlyreducesthechanceofcable
characteristicsalteringthesound. TheabsenceofinputcurrentinFETsallowshighbias
currentsforlinearityandspeedwithoutsacricingDCparameters.
Noiseiskeptlowbymultipleparallelingofinputdevices,carefulselectionofcircuit
impedances,andpre-screeningofdevices. TheClass A complimentaryfollowersusedto
drivethepreamplifieroutputareofsuchspeed,linearity,andlowoutputimpedancethatno
feedbackcorrectionisrequiredorused. Theadvantageofthisisthatthecircuit'sperfect
stabilityandtransientresponsearepreservedintoawiderangeofdicultandunpredictable
loads.Variationinsound,whichcouldoccurthroughinteractionswithinterconnectcablesand
othersystemelementsarethusavoided.
Untilrecently,perfectvolumecontrols(attenuators)didnotexist. Thisisbecause
conventionalstereopotentiometershaveseriouschannelmistracking(20%typically),
becomenoisywithage,wearout,andhavepoorresolutionoflevel-particularlywhen
operatedbyamotorasrequiredforremoteoperation.Inanattempttosolvetheseproblems,
manymanufacturershavebeenusing"switchedattenuators",whicharediscrete,resistor
laddersbuiltonrotaryswitches.Butwhiletheseeliminatechannelmistracking,theyintroduce
newproblems,includinglimitedresolution,steppingtransients,andcannotbeoperated
remotely. Andtheystillwearout.
Theylimitresolutionbecausethemostcontactsavailableonrotaryswitchesarethirty-one.
ThisrequirestwoorthreedBstepsinordertogetenoughrangeoutoftheattenuator,which
isn'tafineenoughresolutionformostlisteners.Switchedattenuatorsalsointroduceswitching
transients(a"click"or"pop")eachtimetheychangepositions.
Thisnoisecomesfromtwosources. Thefirstismechanicalnoisefromtheswitchitselfasits
ball-detentmechanismmovesfromdetenttodetent.Butamoretroublesomesourceisthe
voltagedifferencecausedbythechangeinthemusicalwaveformduringthetimeittakesthe
switchtomovefromonepositiontothenext. Thegreaterthevoltagedifference,thelouder
thetransient.
7
DESIGNPHILOSOPHY
1.Finishes- Allexteriorandinteriormetalpartsareanodized.Whilepaintmaybemore
impactresistant,theanodizedsurfaceismoreresistanttosolventsandpreventscorrosion.
Moreover,theanodizedparts'appearancecanbeenhancedbyeithergrainingorbead-
blastingthesurface.
2.CircuitBoard-Circuitboardsarefiberglassepoxywithgoldplatingoveratin/nickelbarrier.
Thisgoldlayerwillnotcorrode,whilethebarrierplatepreventsthegoldfrommigratingtothe
lowercopperlayeranddetractingfromitsappearance.
3.Resistors- Allarehighreliabilitymetalfilm1%resistors.
4.Capacitors- Allcapacitorsareofhighquality. Theonlyelectrolyticsusedareinthepower
supplywherelargenumbersprovideenormousfilteringcapacitanceforthesupply.
5.Semiconductors- Therearenointegratedcircuits(IC)tobefoundinthecircuitpath.Very
highqualitydualFETsaretheonlysourceofvoltagegainandwereselectedfortheirsuperb
noiseperformanceandprecisionmatching. Theremainingsemiconductorsarealsoofvery
highquality,eachpossessingparametersideallysuitedforthespecificapplication.
6.Connectors-CodaemploysastandardRCA configurationwithagoldplatedcase. The
balancedconnectorsareNeutriksfromSwitzerland.
7.Wire- Allsignalwirehasbeeneliminatedwheneverpossible.Wherewireisused,Coda
employssilverplatedcopper,141strand,18gaugewirewithasiliconeinsulation.
8
TECHNICAL DATA
FrequencyResponse
Distortion
Gain
MaximumOutput
Noise
InputImpedance
OutputImpedance
Crosstalk
PowerSupplySpecifications
Dimensions
:
-3dB@5Hzto200kHz
:
<.005%from10Hzto40kHz@5Vpeakinto600ohmsorhigher,shuntedby1000pForless.
:
12dBplus0-18dBvariableperinputin1dBsteps.UnitygainwhenBypassfeatureis
enabled.
:
10Vpeak
:
<110dBA referencedto1Voutput
:
20kOhmsbalancedorunbalanced
:
50Ohmsnon-reactiveunbalanced
100Ohmsnon-reactivebalanced
:
90dB@20kHz
:
Regulatedsupplywithshieldedtoroidaltransformerand19,800uFoflow-ESRcapacitance
andcapacitorssmoothingtheregulatoroutputs.
:
Height: 2.5”Faceplate,2.85”Overall
Width: 18”Faceplate,17.0”Chassis
Depth: 9.75”Overall
Weight: 14.0lbsShipping
PowerConsumption: 10Watts
9
CARE&HANDLING
Theinterioroftheunitrequiresnospecialcare.Ifitbecomesnecessarytocleantheexterior,
asimpledustingmaybeallthatisrequired.Ifacleanerisnecessary,anydilutecommercial
ammoniabasedproductwillbeappropriate.NEVERuseanyabrasiverags,cleanersor
chemicalsolventsonCodaproducts.
Whenhandlingtheunit,takecarenottomarthealuminum. Aluminumisamediumhardness
metalandcanbescratchedbythehardertoolsteels.
Avoidexposingtheunittodirectsunlight,andkeepitawayfromsourcesofintenseheat.
Donotthrowawaythecartonorassociatedpackingmaterial. Theyareidealifyouneedto
packtheunitformovingandintheunlikelyeventthatservicingisneeded,theywillbe
necessaryforsafeshipment.
Besuretoprovideadequateinsurancewhenshipping.
10
WARRANTY &DISCLAIMER
I.Warranty- AnyfailureoftheCodaproduct,hereafterknownastheproductororiginal
product,tooperateortomeetspecifications,applicableattimeofmanufacture,duetoa
manufacturingdefectorcomponentfailure,willbecorrectedbyCoda Technologieswithout
chargeforpartsorlabor,foraperiodoftenyearsfromdateoforiginalpurchase.Coda
Technologieswillprovideforsurfacetransportationtoandfromthefactoryforaperiodofone
yearfromdateoforiginalpurchase.
II.Procedure-IftheproductshouldrequireserviceunderwarrantycontactCoda
Technologiesatthelocationonthebackcoverofthismanualforshippinginstructions.
ProductspurchasedoutsideoftheUnitedStateswillbecoveredbythewarrantyconditions
extendedbytheimportingdistributorwhichmaydifferfromthosegivenabove.
III.ExclusionofCoverage-Coda Technologiesisnotobligatedtoservicetheproductin
certainconditions,asaccordingtothefollowingsubsections.
a. Theproducthasbeendamagedthrough:
i.operationnotinaccordancewiththeinstructionsinthismanual
ii.abuse,tampering,modificationoraccident
iii.serialnumberdefacement
B.
c. TheproducthasbeentransportedoutsideoftheUnitedStatesof America.
IntheseconditionsanyservicewillbemadeatCoda Technologiessoleoption.
IV. TotalLossandReplacement-Iftheproductissubmittedforserviceduetoasevere
malfunctionwhichhascauseddamagesufficientenoughtomakearepairattemptinfeasible,
theproductwillbereplacedwithanotherunitofequalorsuperiorspecifications.Coda
Technologiesproductlineisfrequentlyupdatedandchanged,andthespecificmodeland
versionoftheoriginalproductmaybediscontinuedatanytimewithoutnotice.Inthiscaseno
guaranteesaremadethatthereplacementunitwillbevisuallysimilartotheoriginalproduct.
V.SubjectiveDifferences-Noguaranteeismadethattheproductwillperformtoany
specificationsthatcannotbemeasuredandconfirmedwithprecisionaudioanalysis
equipment.Coda Technologiesisonlyobligatedtomakerepairswhichwillbringtheproduct
intocompliancewiththespecificationsstatedinthismanual.
VI.UnnecessaryService-Inallconditions,iftheproductissubmittedforserviceandfound
tobeoperatedwithoutfaultandwithinspecifications,shippingchargeswillbebilledtothe
customer.
Thiswarrantygivesyouspecificlegalrights. Youmayhaveotherrightswhichvaryfromstate
tostate.
Disclaimer-Coda Technologiescannotbeheldresponsibleforanydamagecausedbytheir
products,includingbutnotlimitedto:
a.DamagetospeakerscausedbyfailureofaCoda Technologiesproducttomute
ordisableitselfasexpectedordescribedinitsmanual.
b.DamagecausedbyconnectingaloadtoaCoda Technologiesproducthaving
animproperimpedanceasdescribedintheproductsmanual.
c.Damagecausedbydefectsindesign,constructionorcomponentquality.
Theproducthasbeentransferredtoathirdparty.Inthiscasethewarranty
Iisvalidfor5yearsfromdateofmanufactureasdeterminedfromtheserialnumber
11
WARRANTY REGISTRATION
FillinthisregistrationsheetandfaxormailittoCoda Technologiestoensureyouareinour
warrantysystem. Thiswillfacilitatewarrantyserviceshoulditbecomenecessary.
Itisrecommendedthatyouretainacopyofthisformforyourownrecords.Coda
Technologies’addressandfaxnumberarelocatedonthebackofthismanual.
MODEL DESIGNATION:
SERIAL NUMBER:
DATEOFPURCHASE:
PLACEOFPURCHASE
OWNERINFORMATION
NOTES:
Name:
Address:
City: State: Zip:
Phone:
Name:
Address:
City: State: Zip:
Phone:
12
WARRANTY REGISTRATION
FillinthisregistrationsheetandfaxormailittoCoda Technologiestoensureyouareinour
warrantysystem. Thiswillfacilitatewarrantyserviceshoulditbecomenecessary.
Itisrecommendedthatyouretainacopyofthisformforyourownrecords.Coda
Technologies’addressandfaxnumberarelocatedonthebackofthismanual.
MODEL DESIGNATION:
SERIAL NUMBER:
DATEOFPURCHASE:
PLACEOFPURCHASE
OWNERINFORMATION
NOTES:
Name:
Address:
City: State: Zip:
Phone:
Name:
Address:
City: State: Zip:
Phone:
7850CUCAMONGA AVENUE#34
SACRAMENTO,CA 95826USA
phone
onthewebat
emailusat
fax
+01916.383.3653 +01916.455.3653
CODA.CC
[email protected]
/