Dolby Laboratories DP570 4.13 Using an External Shaft Encoder to Control Master Volume, 4.14 Emulator Bypass, 4.15 Solo Input Mode , 4.16 Unity Gain Mode

36 Dolby® DP570 Multichannel Audio Tool User’s Manual
Using the DP570 Features
4.13 Using an External Shaft Encoder to Control Master Volume
ThemastervolumefunctionisavailableonDP570sthathavetheCat.No.548Analog
OutputCardinstalled.TheGPI/Oporthasthreepinsthatallowcontrolofmastervolume
remotelybyusingashaftencoder.Table 4‐5describestheinterface.
Table 4 ‐6describestheelectricalcharacteristics.
4.14 Emulator Bypass
WhenyouenableEmulatorBypass,thefront‐panelEscbuttonisilluminated.Inthis
mode,theonlysettingsthataffecttheoutputaretheroutersettings.Monitoringoptions
arelimitedtoprogramselection.Ifyouareusingthe Lt/Rt Input,thatsignalissent,without
decoding,totheLeftandRightemulatoroutputs.Bassmanagementremainsactive.
4.15 Solo Input Mode
TheDP570providesatwo‐channelanaloginputthatcanberoutedtotheanalogoutputs.
ThisinputiscalledSolobecausethefeatureprovidesawaytorouteastandardsignalfrom
amixer(suchasthemixer’ssolobusoutput)intothemonitorchain.Thefeaturecanalso
beusefulasageneral‐purposeanalogbypass.
SoloInputmodebypassesthedigitalaudioinputs,andonlythesoloinputsfromthe
Analog I/O connectoronthebackpanelroutetotheLeftandRightoutputs.IftheMono
speakeroutputisselected,theinputsignalsaresummedandfedtotheMonooutput.
TheSoloinputisavailableonlybydrivingtheSoloControllineontheGPI/Oport.TheSolo
Controlline(pin6)islevel‐triggeredandisactiveinthehighstate.ThestatusoftheSolo
inputdisplaysonthefront‐panelSoloLEDandisindicatedontheSoloTally line(pin5)
ontheGPI/Oport.
4.16 Unity Gain Mode
UnityGainmodedefeatstheaudibleeffectsofdialoguenormalizationwhileallowingthe
dialnormvaluetobeusedinchoosingdynamicrangecontrolsettings.Itisvaluablewhen
theemulatoroutputsoftheDP570arereturnedtotheconsoleforuseasmonitorinputs.
Table 4-5 Shaft Decoder Signal Descriptions
Signal Pin Description
Shaft121Shaftencoderinput.Twosquarewavesinaquadraturephaserelationship:
Shaft0leadsShaft1by90°:volumeincreases.
Shaft0lagsShaft1by90°:volumedecreases.
Shaft020
ShaftPresent 22 Groundthispintoactivatecontrolviashaftencoder.Pulledhighinternally
(10kto+5V).
Table 4-6 Shaft Decoder Signal Electrical Characteristics
Characteristic Min Max
VT+Positive‐goinginputthresholdvoltage 1 .2V2.1V
VT–Negative‐goinginputthresholdvoltage 0.5V1.4V
VHHysteresisvoltage 0.4V1.5V