Cyrus 8 DAC - DC OFFSET ADJUSTMENT; DC offset adjustment (no signal condition)

DCOFFSETADJUSTMENT
©CyrusAudioLtdJun2014 18 Cyrus6DAC,Cyrus8DACservicemanualIssue1
DCoffsetadjustment(nosignalcondition)
TheDCoffsetadjustmentsetstheDCvoltageatthespeakeroutputterminals.DCoffsetshould
alwaysbecheckedasamatterofroutinewhenanamplifierisreturnedforrepair,whetherthe
poweramplifiersectionhasrequiredrepairornot.
ThefollowingprocedureshouldbefollowedexactlytosettheDCoffsetvoltagetothecorrect
value.IftheDCoffsetvoltagewillnotsetcorrectly,thismayindicateapoweramplifierfault.
 Switchoffthepowertotheamplifier.
 Disconnectallloudspeakersordummyloads.
 ConnectaDVMsettoreadmVtotheleftloudspeakerterminals(ashortcableterminated
with Cyrus speaker connectors is recommended to make certain contact with the
terminals).
 Switchonthepowertotheamplifier,andbringitoutofstandby.Setthevolumelevelto‐
15dB.
 Leavetheamplifiertosettlefor5minutes.
 CheckthevoltagereadingontheDVM.Avoltagewithintherange0V50mVisacceptable 
andwillnotrequireanyadjustment.Ifthevoltageisoutsideofthese limits,adjustRV203
tosettheleftchanneloffsetwithintherange0V50mV.
 ConnecttheDVMtotherightchannel.
 Repeatthe voltagechecktothesamelimitsandadjustRV204tocorrecttherightchannel
offsetifnecessary.
 Leavetheamplifiertosettlefor15minutesandre‐checktheDCoffsetvoltages.

0.0mV
RV204
RV203