installation
Placement
Foroptimumsourcelocalizationwithinthestereoimage,a
pairof4311sshouldbearrangedsothatthelistening
posi-
tioniscenteredbetweenthetwosystemsandnomorethan
30degreesoff-axishorizontally.Verticalorientationshould
betreatedina similarmanner.(Note:Smoothestfrequency
responsewillbeheardfroma listeningposition15degrees
off-axisfromeitherunit.)Ifthreeormore4311s areused,the
enclosuresshouldbeangledtowardthehorizontalcenter
lineofthearraytoobtaintherecommendedpatternoverlap
atthelisteningposition.Ifa pairof4311sareplacedhorizon-
tally,andfairlyclosetogether,a widerstereoperspectivewill
berealizedbyorientingtheenclosuressothatthehigh
frequencydirectradiatorsarefurthestapart.Ifphysically
practical,
locatingthe4311ssothatthehighfrequencyunits
arenearearlevelisgenerallypreferable.
SystemConnection
Inputtothe4311isviaspring-loadedterminalpostslocated
onthebackoftheenclosure.Theterminalsarecolorcoded
tofacilitateconsistentpolarityconnectionbetweenunitsin
stereoormulti-channelinstallations.Eighteengaugeinsulated
wireistheminimumsizerecommendedforconnectionsup
to50feet.Heaviergaugewireisrecommendedforgreater
distances;16-gaugefrom50to100feetand14-gaugefrom
100to200feet.
Important:Whenconnectingordisconnectingloudspeakersfrom
anamplifier,theamplifiermustbeturnedoff.Makingconnections
whiletheamplifierisoperatingcouldseriouslydamagetheloud-
speakersystemandvoidthewarranty.
SystemAdjustment
Thefrequencydividingnetworkofthe4311isprovidedwith
frontpanelcontrolstoallowseparateregulationofoutputin
the1500to6000Hz"presence"rangeandthe"brilliance"
regionabove6000Hz.Labeled"Presence"and"Brilliance','
thecontrolsarecontinuouslyvariablefrommaximumtofull
off,withtheflattestresponse(measuredinananechoic
environment)achievedatthemidpointsoftheirtravel.With
suitablesettingsofthetwocontrols,thefrequencyresponse
contourofthe4311canbealteredtocompensateforalmost
anyacousticalenvironment,ortoachievethetonalbalance
desired.
Controlscalesareclearlymarkedfrom0 to10,with
"5"
astheirmidpoints,sothatspecialsettingscanbelogged
andeasilyresetwhenneeded.
PresenceandBrilliancecontrolsarelocatedonthefrontpanel,
belowthegrille.Flattestresponse,measuredina laboratoryenviron-
ment,willbeachievedwithbothcontrolssetat"5:'/
AmplifierPower
The75-Wattcontinuousprogrampowercapacityofthe4311
isindicativeofan"average"programlevelthatcanbetoler-
atedbythecomponentswithoutdamage;however,transients
canexceedthislevelbya considerablemarginwithout
danger.Toachievetheamplifierpowerreservenecessary
foraccuratetransientreproductionathighloudnesslevels,
the4311maybedrivenbyamplifiersratedupto150Watts
RMS(perchannel).Evenlargeramplifierscanbeemployed
ifnormalprecautionsagainstinputdevicedistortionor
amplifierclippingarefollowed.Forportableinstallations,
amplifiershavingaslittleoutputas10WattsRMS(perchan-
nel)willdrivethe4311touseablevolumelevels.
ComponentRemoval
Tooptimizethesounddispersioncharacteristicsofthe
loud-
speakersystem,maintaintheacousticalintegrityofthe
enclosureandfacilitateinspectionandservice,allcompo-
nentsmountdirectlytothebafflepanelandareremovable
fromthefrontoftheenclosure.
Gr/V/e-Thegrilleissecuredtotheenclosurebyhook-and-
pilemountingtapeateachcorneroftheassembly.Toremove
thegrille,graspitatthebottomedgeandgentlyliftitfrom
theenclosure.Toreplacethegrille,repositionitontheen-
closureandapplylightpressureatthecorners.
Low Frequency—The lowfrequencyloudspeakerismounted
withfourPhillips-headscrewsthreadedintoT-nutfasteners
whichareanchoredonthebackofthebafflepanel.After
placingtheenclosureonitsbackona clean,paddedsurface,
carefullyunscrewthemountingscrewswithoutapplying
pressurethatmightdislodgetheT-nuts.Whenthescrews
havebeenremoved,gentlylifttheedgeoftheloudspeaker
framefromthebafflepanel,disconnectthewiresatthe
terminalsandremovetheloudspeakerfromtheenclosure.
Midrange and High Frequency—The midrangetransducer
isheldinplacebyfourself-tappingscrewsateachcorner
ofitsframe.Carefullyremovethescrews,lifttheunitfrom
theenclosureanddisconnecttheleadsattheterminals.The
highfrequencydirectradiatorismountedina similarmanner,
withtheexceptionthatitsinputisviatabconnectors.
Dividing Network-The dividingnetworkismountedtothe
rearofthebaffleandheldinplacebymachinescrewsextend-
ingthroughthefrontofthepanel.Togainaccesstothe
network,removethetransducers,pullthewireleadsfrom
themidrangesub-chamber,disconnecttheleadsatthetab
connectorsontheinputterminalsatthebackoftheenclo-
sure,
carefullypeelbackthefoilnameplatewhichconceals
thetwomountingscrews,removethescrewsandliftthe
networkoutthroughthelowfrequencyloudspeakeropen-
ing.
Note:Malfunctionofthenetworkishighlyunlikely.Since
thenameplateisgenerallydestroyedduringremoval,itis
notrecommendedthatthenetworkberemovedsimplyfor
thepurposeofinspection
