Owner`s manual

7
Description
YourSageSCSsubwooferusesamodernimplementationofanoldideaforhigh
quality,lowdistortionbassreproduction.WhiletherootsoftheRegenerative
TransmissionLine
™
gobacktothe1950’s,itisthecombinationofmoderncom-
putermodelingandthevastlymorepowerfulmotorsofcontemporarydriver
designthatmaketheRTL
™
sospecial.
Regenerative
Transmission Line™
Thereisaclassofbassenclosuresthathas
beenaroundsincethe1950’s,whichcan
bedescribedgenericallyas“lowfrequency
tappedwaveguides”or“tappedpipes.”Itwas
anideathatwasabitaheadofitstimethen,
sincefullyoptimizingitsuserequiredboth
powerfuldriversandcomputermodeling.
Butifyouareintosuchthings,checkoutUS
Patent2,765,864(ledin1955),andanAESpaperpublishedin1959,“Analysis
of a Low Frequency Loudspeaker System.”Wehavepublishedbothonourweb-
siteforyourconvenience,at
http://www.wisdomaudio.com/support_documents.php
Wehaveutilizedsophisticatedmodelingsoftwareinordertofullyoptimizeour
enclosures,andhavedevelopeddriversthatarespecicallyoptimizedforthis
application.Wecallouruniqueimplementationofthisrelativelyoldideaa“Re-
generativeTransmissionLine
™
”subwoofer,or“RTL”subforshort.
Alldynamicdriversdevelopenergyonbothsidesofthediaphragm,withthe
rearenergybeing180°outofphasewiththefrontenergy.Ifyouallowthe
drivertooperateinfreespace(noenclosure),thefrontandrearenergieslargely
canceleachotherout—especiallyatlowfrequencies.
InourRegenerativeTransmissionLine
™
subwoofer,theenergyfromtheback
sideofthedriverissentalongalong,foldedpathinsuchawaythatitslowest
frequenciesarrivebackatthefrontsideofthedriverinphase,effectivelysum-
mingtoanincreaseof6dBinoutput.Thus,theenergyfrombothsidesofthe
wooferconeisusedinaproductiveway,resultinginasubstantialreductionin
distortionandaneffectivesurfaceareathatistwicewhatyouwouldotherwise
expect.Asanexample,theeffectiveradiatingsurfaceareaintheSCSisroughly
equivalenttoa13”diameterroundwoofer,yettheenclosureisonlyabout7”
wide.
Theresultsarequitestunning.Lowfrequenciesarestrikinglydynamicandre-
sponsive,andintegratequiteseamlesslywiththefastanddetailedSageSeries
planarmagnetichybrids.Asanexample,theSCSiseasilyhiddenbehindasofa,
orwithinasetofrisersinadedicatedhometheater,yetisonly–3dBat20Hz
andcanoutputinexcessof120dBat22Hz(measuredatitsoutputportto
minimizetheroom’seffectsonthemeasurement).