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areallbehindthelisteners,creatingabig“hole”inthesoundeld
betweenthefrontandtheback.)
a 7.2 channel system layout
Subwoofer Placement Subwoofersoffersomewhatgreaterexibilityinplacement,sincethefrequen-
ciestheyreproducearenotreadilylocalizablebythehumanear.Thisisdueto
thefactthatthewavelengthstheyreproducearemorethantenfeet(3meters)
long,butourearsarelocatedonlyabout6-7inches(≈17cm)apart.Thusthese
extremelylongwavesdonotcontributemeaningfullytotheimagingthatthe
mainspeakerscreate.
However,thisfactdoesnotmeanthattheplacementofthesubwoofershasno
effectonthesoundqualityintheroom.Farfromit.Thesubwoofersarethe
mostlikelytosufferfromtheresponseirregularitiesintroducedbytheroom
itself,operatingastheydobelowapproximately80Hzinmostsystems.
Recentresearchintothebehaviorofroomsasafunctionofspeakerplacement
hasconcludedthat—ifyouhavethefreedomtodoso—therearesignicant
advantagestoplacingseveralsmallersubwoofersaroundtheroom,ratherthan
relyingonasinglelargewoofer.Moreover,theoptimumplacementisusu-
allycenteredoneachofthefourwalls.Ifyouhavetheluxuryofdoingso,this
simpleplacementstrategycanreducethesizeoftheroom’sresponseirregulari-
tiesfrom20decibelsdowntoperhapsaslittleas6-8decibels.
Reducingtheroom’sinherentproblemstothisdegreeisahugeadvantage.It
allowstheSC-1toputitsconsiderableabilitiestoworkonperfectingyoursys-
tem’sresponse,ratherthanontryingtoperformmajorcorrectivesurgery.
Room Treatment Rectangularroomshavesixreectingsurfaces(fourwalls,ceilingandoor)
thatreectsoundtothelistener,aftervariousdelaysintroducedbytheindirect
routesthesoundwavestakeontheirwaytothelistener.Theserstreec-
tionsareparticularlydamagingtosoundquality.Lookingatthesimplestcase
ofstereoreproduction,youhaveaminimumoftwelverstreectionpointsin
yourroomthatdeservesomeattention.
Unfortunately,itisoftendifculttodomuchabouttheceilingandoorreec-
tions,eventhoughtheyarearguablythemostdestructive.(Theminimizationof
thesereectionsisoneofthestrongestargumentsforthetall,linesourceloud-
speakersthatWisdomAudiobuilds.)Thisleavesyouwitheight“rstreections”
thatyoushouldconsiderminimizingsomehow.Thesepointsareeasilyfoundby
havingafriendmoveasmallmirroralongthefourwallsoftheroom,whileyou
sitatthelisteningposition.Anyplaceonthewallwhereyoucanseeareec-