Manual

FilterType Highpassfactors Lowpassfactors
Bessel12dB/Oct. 1.45 0.69
Butterworth12dB/Oct. 1.31 0.76
Bessel18dB/Oct. 1.37 0.73
Butterworth18dB/Oct. 1.19 0.84
Bessel24dB/Oct. 1.35 0.74
Butterworth24dB/Oct. 1.15 0.87
Bessel48dB/Oct. 1.39 0.72
Butterworth48dB/Oct. 1.08 0.93
CrossoverFilterSlopes
Itshouldalsobenotedthattheturnoverfrequencydisplayedonthescreenisthe-3dBpointforalltypes
exceptLinkwitz-Rileywherethe-6dBpointisshown.Ifthe-6dBpointistobeusedfortheBesselor
Butterworthfilter,taketherequiredcrossoverfrequency,multiplythisbytheappropriatefactorfromthe
followingtableandthenselecttheclosestavailablefrequencyonthedisplay.
Pleasenotethatunlikeconventionalanaloguecrossovers,crossoverpointsandslopesaresetwithabsolute
accuracysincecomponenttoleranceproblemsdonotoccur.
Pleaseseepagefordetailsofhowtoadjustthehighandlowpasscrossoverfiltersettings.
AfurtheradvantageoftheSP27Seriesoverconventionalproductsistheprovisionofanindependently
adjustabledelaysectionforeachoutput.Thisallowsthetruearrivaltimefrommultipledriverstoprecisely
alignedratherthanrelyingonthecompromise'phaseadjust'approach.Delaytimeisadjustablein03Ssteps
(0.1mm).
Pleaseseepagefordetailsofhowtoadjustthedelaytimes.
Toconvertfromunitsoftime(i.e.milliseconds)tounitsofdistanceusethefollowingformula:
1millisecond=343mm(1.126ft)@20C(68F)
Tocalculatetimedelayforaknowndistance,use:
Timedelay=
20.06x273+C
whereCisthetemperatureinC.
Tosimplifythisequationat20C.
Delaytimeinmilliseconds=
(Distanceinmetersx2.192)or(Distanceinfeetx0.955)
Note:Centigrade=(Fahrenheit–32)x0.5555.
TimeAlignment
.
Distanceinmeters
32