Owner`s manual

11
Surround Speakers Surround channel geometry
Ina5.xchannelsystem,thesurroundshouldbeplacedeitherdirectlytothe
sidesoforslightlybehindthelisteningarea(90°–110°fromthecenterchannel,
asseenfromabove).Ina7.xsystem,thesurroundspeakersshouldbecloserto
90°fromthecenterspeaker,andthesurroundbackspeakersshouldbeatap-
proximately135°–150°fromthecenterspeaker.Thisconformstoindustrystan-
dards,andensuresthatyouhearwhatwasintendedfromaspatialplacement
pointofview.(Toooften,thesurroundspeakersareallbehindthelisteners,cre-
atingabig“hole”inthesoundeldbetweenthefrontandtheback.)
LR
C
Sub 1
Sub 2
L
s
R
s
R
b
L
b
22°
30°
90°
110°
135°
150°
0°
a 7.2 channel system layout
Onepossibleexceptiontotheseguidelines:ifyouhaveaTHX
®
-certiedpro-
cessorandareusingtheTHXAdvancedSpeakerArray™circuitry,youshould
followtheguidelinesinyourowner’smanualfortheprocessor.Usingthis
technology,itcanactuallybemoreeffectivetohavetherearspeakersina7.x
systemdirectlybehindyouandimmediatelyadjacenttoeachother.
Subwoofer Placement Subwoofersoffersomewhatgreaterexibilityinplacement,sincethefrequen-
ciestheyreproducearenotreadilylocalizablebythehumanear.Thisisdueto
thefactthatthewavelengthstheyreproducearemorethantenfeet(3meters)
long,butourearsarelocatedonlyabout6-7inches(17cm)apart.Thusthese
extremelylongwavesdonotcontributemeaningfullytotheimagingthatthe
mainspeakerscreate.
However,thisfactdoesnotmeanthattheplacementofthesubwoofershasno
effectonthesoundqualityintheroom.Farfromit.Thesubwoofersarethe
mostlikelytosufferfromtheresponseirregularitiesintroducedbytheroom
itself,operatingastheydobelowapproximately80Hzinmostsystems.
Recentresearchintothebehaviorofroomsasafunctionofspeakerplacement
hasconcludedthat—ifyouhavethefreedomtodoso—therearesignicant
advantagestoplacingseveralsmallersubwoofersaroundtheroom,ratherthan
relyingonasinglelargewoofer.Moreover,theoptimumplacementisusually
centeredoneachofthefourwalls,ordeepinthecornersoftheroom.Ifyou
havetheluxuryofdoingso,thissimpleplacementstrategycanreducethesize
oftheroom’sresponseirregularitiesfrom20decibelsdowntoperhapsaslittle
as6-8decibels—atremendousimprovement.