Recommended for professional audio and bass guitar applications as a woofer in a vented enclosure. Also works well for PA in a sealed or bandpass enclosure. Woofer | Midbass | Midrange | Pro Audio | Home Stereo | Home Theater | Bass Guitar Box Type: Sealed | Vented | Horn Loading SPECIFICATIONNominal Basket Diameter12", 305 mmNominal Impedance*8 ΩPower Rating*Program Power500 WWatts250 WResonance47 HzUsable Frequency Range43 Hz - 3.8 kHzSensitivity*98 dBMagnet Weight38 oz.Gap Height0.312", 7.9 mmVoice Coil Diameter2", 51 mmTHIELE & SMALL PARAMETERSResonant Frequency (fs)47 HzDC Resistance (Re)5 ΩCoil Inductance (Le)0.64m HMechanical Q (Qms)6Electromagnetic Q (Qes)0.5Total Q (Qts)0.46Compliance Equivalent Volume (Vas)120.1 liters / 4.24 cu.ft.Peak Diaphragm Displacement Volume (Vd)237 ccMechanical Compliance of Suspension (Cms)0.29 mm/NBL Product (BL)10.8 T-MDiaphragm Mass Inc. Airload (MMs)40 gramsEfficiency Bandwidth Product (EBP)94Maximum Linear Excursion (Xmax)4.4 mmSurface Area of Cone (Sd)538.9 cm2Maximum Mechanical Limit (Xlim)11 mmMOUNTING INFORMATIONRecommended Enclosure VolumeSealed25.5-35.4 liters / 0.9-1.25 cu.ft.Vented36.8-139 liters / 1.3-4.9 cu.ft.Driver Volume Displaced0.071 cu.ft. / 2 litersOverall Diameter12.03", 305.6 mmBaffle Hole Diameter11.07", 281.2 mmFront Sealing GasketYesRear Sealing GasketYesMounting Holes Diameter0.25", 6.4mmMounting Holes B.C.D.11.59", 294.4mmDepth5.5", 139.7 mmNet Weight7.5 lbs, 3.4 kgShipping Weight9.7 lbs, 4.4 kgsMATERIALS OF CONSTRUCTIONCoil ConstructionCopper voice coilCoil FormerPolyimide formerMagnet CompositionFerrite magnetCore DetailsVented and extended core Basket MaterialsPressed steel basketCone CompositionPaper coneCone Edge CompositionCloth cone edgeDust Cap CompositionSolid composition paper dust cap