ATI Audio DA206 Operating instructions

AudioTechnologiesInc. |154 CooperRoad#902|WestBerlin,NJ08091|Voice856-719-9900 |Fax[phone] |www. audio.com
©Copyright1997-2005, AudioTechnologiesIncorporated-PrintedinUSA
DA206 ANDDA412
DISTRIBUTION AMPLIFIERS
OPERATINGAND MAINTENANCEMANUAL

AudioTechnologiesInc. |154 CooperRoad#902|WestBerlin,NJ08091|Voice856-719-9900 |Fax[phone] |www. audio.com
DESCRIPTION
The DA206 and DA412 provide twoorfour1x3distribution amplifierchannelswith
balanced inputsand +24dBmoutputs.Amastergainadjustmentforeachchannel
controlsallthreeoutputstogethertoadjustforvarying inputswhileindividualtrimmersfor
eachoutputallowadjustmentovera20dBrange toaccommodate-10dbu semi-proup to
+8dBmline levels.
Anotherofthe DA206 andDA412Distribution Amplifiersmanyclaimstofameisthe use
ofXLRtype inputandoutputconnectors.XLRsareeasytousebutmakeparalleling
inputsfor1x6or1x12 operation difficult. However, if you lookunderthe hood (removethe
top cover) you will find someconvenientjumperplugsthatallowyou toparallelinputsA
and B(P4&P5), Band C(P6&P7), Cand D(P10 &P11), individuallyorsimultaneously.
Ifyou aremakingastereo 1x6DA,driveinputsAand CwithLeft and Rightsignalsand
jumperinputsAtoBand CtoD.You can usethe emptyinput connectorstoloop-thruto
the otherdozen ATIdistributionampsthatwehope you areusing.
The DA208/416 hasaquietinputstage withexcellentcommon mode humrejection.An
internalgainselectionjumperplugforeachinput(P2,P3,P8,P9)optimizesfornominal
inputsat -20dBu, -10dBuor+4dBu. Inputsup to+24dBuwillnot clipinthe +4dBuposition
and inputsignalsexceeding +24dBuwillclipcleanlywithno hang-up orphasereversal.
Aquad bi-fetopampformsthethree variablegainoutputadjustsstages.The variable
gainstagesutilizeaunique circuitarrangementthatallowsustoprovide asmooth,
logarithmicgaincontrolforeachoutputusing an inexpensive(butgood)linearcermet
potentiometer.Sinceweactuallyreducethe stage gainforlowoutputsratherthan taking
the moreconventionalapproachofreducingthe inputleveltoafixed gainamplifier,we
can usethe DAatlowoutputlevelswithverylittlenoisepenalty.You can usetheDAto
matchconsolemediumlevelinputs(-20dBu)ortodrivesemi-proIHFinputswithout
requiring outboardattenuatorpads.
Activebalanced outputdriverssensethe voltage on theirhigh and lowoutputlinesand
will shutoff drivetoagrounded outputline whiledoubling the driveon the other.This
capabilityallowsyou toconnectthe outputstobalanced orunbalanced loadswithout
regardtowhetherorwhichside ofthe output isgrounded.Maximumoutputatclipping is
+24dBmintobalancedloads,however,even though the gainisthesameundereither
condition,clipping outputisreducedby6dBwhen driving an unbalanced load sincethe
full output swing capabilityof onlyone driverof the twoisavailable.
YourEncoreDAoperatesfromabipolar15VDC regulated supply.The powersupplyis
designedforminimumsusceptibilitytopowerlinetransientsand conductedRFIusing
ferritebeads, doublebypassing and anon-concentricwound semi-toroidaltransformer.

AudioTechnologiesInc. |154 CooperRoad#902|WestBerlin,NJ08091|Voice856-719-9900 |Fax[phone] |www. audio.com
INSTALLATION
MOUNTING
YourDAisdesigned forrackmounting on standardEIA13/4-inchcenters.Eachunit
dissipatesapproximately10 wattsand isdesigned foruseinan officeenvironment. Avoid
excessiveheatbuildup (suchasmightbe due tonearbypoweramplifiersinunventilated
racks)toensuremaximumcomponent life.
WIRING
AUDIOCONNECTIONS
XLRtype inputsand outputsarewired withpins2asHiand pins3asLo. Pin1 (shield)of
all inputandoutputconnectorsarepermanentlygroundedinaccordancewiththelatest
AES recommendations.The pin1 groundsarerouted viaalarge lowimpedanceground
pathdirectlytothe chassisseparatelyfromanyaudioground paths.Internalcircuit
ground isalsoconnected tothechassisforshielding through an independentpath.AC
ground (green wire)isalsoseparatelygrounded tochassis.Activebalanced outputs
requireareferenceground connection tothe receiving deviceforproperoperation.This
ground iscarriedthrough pin1.Ifthe pin1shieldgroundisnotcarriedthrough tothe
receiving device,the ACground maycompletethisground,rackframeorstudioground
system.Noisygroundsrequireexcellentcommonmode rejectioninthe receiving device
forquiet systemoperation.
Wehavetaken measurestokeep RFIoutofyourEncoreSeriesDAincluding splitand
bypassed inputnetworks,beaded,bypassedand isolated powerinputs,nonconcentric
wound,semi-toroidalpowertransformers,doubleground plane PCboardsand anice
enclosuretokeep rainandsnowoff the circuitboards.However,indifficultbroadcast
applications,the RFshieldingandsuppression systemcanbe nobetterthan theground
systemintowhichitistrying todumptheunwanted RF.Foroptimalproduct
performance, be suretohaveagood grounding system
ADJUSTMENTS
The Masterand individualoutputlevelcontrolsshouldallbe setcloseto2o’clock to
provide nominal+4dBmoutputsforanominal+4dBuinput.Thesesettingsallow+6/-
16dBoutputadjustmentrangearound nominal, whichwillallowoutputsof+10to-12dBm
tobe set. Inaddition the Mastergainhas+10dBtoOFF adjustment range tocompensate
forinput levelvariationsfrom-6dButoinput clipping at+24dBu.
Changing the position ofthe inputgaincompensatesforlowerlevelinputssetting jumper
plugs(P2,P3, P8, P9). Theseplugsadd 14 or24dBof extragaintopermit nominalinputs
of -20dBuand minimuminputsaslowas-30dBufor+4dBmout.
The inputparalleling jumperplugs(P4&P5,P6&P7,P10 &P11)arelocated underthe
hood justbehind the inputXLRconnectors.Theymustbe used inpairs(e.g.P4&P5
together) toproperlyjumperHI&LOinput lines. Thesejumperplugslet you useaDA412
asaQuad 1x3, Stereo 1x6oraMono 1x12 DA.

AudioTechnologiesInc. |154 CooperRoad#902|WestBerlin,NJ08091|Voice856-719-9900 |Fax[phone] |www. audio.com
230VACOPERATION
YourDAiswired for115VAC,50/60Hzoperation unless otherwiserequested attimeof
order.Itcan be easilymodified for230VACoperation byremoving the powertransformer
primaryjumpersW1&W3and inserting ajumperwireinposition W2.Differenttypesof
attachmentplugsorline cordsmaybe required forconnection toalternatesupply
voltages.
MAINTENANCE
Powersupplyvoltagesareregulated byA1and A2to+15 and -15VDC respectively.IC
outputDC voltagesunderno signal;shorted inputconditionsshouldremainwithin
0.1VDC of ground. Agreaterdeviation isan indicatorof ICorcircuit problems.
Inputsand outputsaresusceptibletohigh common mode and differentialACand DC
voltagesfed fromexternaldevicesorappearing on ground
ULLISTING
The DA206 and DA412arelistedbyUnderwriterLaboratoriesas“ListedProfessional
AudioEquipment 2D65”.

AudioTechnologiesInc. |154 CooperRoad#902|WestBerlin,NJ08091|Voice856-719-9900 |Fax[phone] |www. audio.com
SPECIFICATIONS
OUTPUTLEVEL: +24dBmpeakinto600 ohmbalanced load.
THD:.001%typical, 20to20KHz
IMD.05%maximum, SMPTEmeasurement.
SLEWRATE:13 Voltspermicrosecond
RESPONSE:+/-.25dB, 20 to20,000Hz.
NOISE:-100dBmEIN, 20Hz-20KHz
GAIN:40dBmaximum
CROSSTALK: 70dBminimumat10KHz, anypath.
OUTPUTS: Activebalanced,servocontrolled,ground sensing,50ohm
output impedance, DC coupled.
HUMREJECTION:70dBCMRat 60Hz.
INPUTS:20Kohmactivebalanced,splitand RFbypassed.+26dBm
maximuminputlevel
CONNECTORS:XLRtype, Pin2-HI, 3-LO, 1-GND.
POWER:115/230 VAC+/-10%,47 -63Hz,20VA,use.5A,250VAC
fuse, ULlisted, 1/4DX11/4inchesLong.
SIZE: 19”(48.2cm)WX1.75”(4.45cm)HX7.5”(19cm)D.
18lbs.(8.2kg).
MODELSAVAILABLE:DA206 Dual1x3Activebalanced outputs
DA412 Quad 1x3Activebalanced outputs