BBK DK2810HD - Night Mode

2.3.13“Night”mode
TheDolbyDigitalsystemprovidesan
extremelybroaddynamicrangeofplayback
sound-fromgentletoroaring.Itcreatesthe
presenceeffect,especiallywhileseeingmotion
pictures.However,atnightapowerfulsound
withabroaddynamicrangemaygivepleasureto
you,butdisturbandannoyyourfamilyand
neighbors,ifyoujustdecreasethevolume,you
willimmediatelynoticethatyouceasedtonear,
e.g,dialoguesasclearasyoudoatnormal
volume,andsuchsoundeffectsasrustle,
whisperetc.Havemerelydisappeared.Toavold
this,youjusthavetodecreasethevolumeof“
loud”soundsbysimultaneouslyincreasingthe
volumeof“soft”soundswiththevolumeof
“average”soundsleftunchanged,l.e.Just
decreasethedynamicrangeofsoundcontrol.It
usestheprincipleofcompressingtheacoustic
signal’sdynamicrangewhilerecording;
therefore,whileplayingandinverse
transformation(volumeexpansion)takesplace.
Thisiscalled”night”mode.Theregulationlimits
arerestricted,however,toavoiddistortionsof
resultantsignal.
Set-upoftimedelayinthecentralchannel
Sometimesseveralpeoplearelisteningto
themusic,andthespaceislimited.Inthiscase,
youcaninstallthreespeakers(twofrontones
andacentralone)asshowninFig.1.Withthe
distancetothelistenerbeingapproximatelythe
same.Thecentralchanneldelayistobeset
at”0”.
Shouldthecentralspeakerbeinclose
proximitytoleftandrightfrontspeakersas
showninFig.2,orthecentralspeakerbenearer
tolistenerswhencomparedwithfrontspeaker’s
location,orthecentralspeakerbenearertothe
listenerby1foot,inallthesecasesyoumayset
thedelayvalueforthecentralchannelat1ms.
Forinstance,asshowninFig.2,ifthelineC
isby1footshorterthanthelinesRandL,the
delayvalueistobesetat1ms,Ifyoursofais
broadenough,andthereareseverallisteners
sittingonit,itmakessensetolocatethe
speakersinoneline,asshowninFig.3withthe
delayvalueofthecentralchanneltobesetat”0”.
Finally,ifitwillbenecessarytoinstallthe
centralspeakerbehindtheleftandrightfront
speakers,thedelayvalueshallbesetat“0”.
Fig.1.Delayofcentral
channel=0
L=R=C
Fig.2.Smallarea
Delayofcentralchannel
=L=(orR)-C
Fig.3.Smallarea
Delayofcentralchannel=0
L=RC
-12-
Fig.2.Determinedelay
valueastoDolbyProLogic
mode.
Fig.3.Determine
delayvalueastoDolby
Digitalmode.