SPECIFICATION
Nominal Basket Diameter	18", 457 mm
Nominal Impedance*	8 Ω
Power Rating**
Watts	500 W
Music Program	1000 W
Resonance	28 Hz
Usable Frequency Range	37 Hz - 0.2 kHz
Sensitivity***	96 dB
Magnet Weight	67 oz.
Gap Height	0.38", 9.7 mm
Voice Coil Diameter	2.5", 64 mm
THIELE & SMALL PARAMETERS
Resonant Frequency (fs)	28 Hz
DC Resistance (Re)	5.3 Ω
Coil Inductance (Le)	3.43m H
Mechanical Q (Qms)	10.38
Electromagnetic Q (Qes)	0.33
Total Q (Qts)	0.32
Compliance Equivalent Volume (Vas)	493.2 liters / 17.42 cu.ft.
Peak Diaphragm Displacement Volume (Vd)	796 cc
Mechanical Compliance of Suspension (Cms)	0.25 mm/N
BL Product (BL)	18.9 T-M
Diaphragm Mass Inc. Airload (MMs)	128 grams
Efficiency Bandwidth Product (EBP)	84
Maximum Linear Excursion (Xmax)	6.7 mm
Surface Area of Cone (Sd)	1188 cm2
Maximum Mechanical Limit (Xlim)	15.0 mm
MOUNTING INFORMATION
Recommended Enclosure Volume
Sealed	N/a
Vented	85.00-297.00 liters / 3.00-10.50 cu.ft.
Driver Volume Displaced	0.212 cu.ft. / 6.01 liters
Overall Diameter	18", 457.2 mm
Baffle Hole Diameter	16.57", 420.9 mm
Front Sealing Gasket	Yes
Rear Sealing Gasket	Yes
Mounting Holes Diameter	0.28", 7.1mm
Mounting Holes B.C.D.	17.25", 438.2mm
Depth	8.13", 206.5 mm
Net Weight	17 lbs, 7.71 kg
Shipping Weight	20.5 lbs, 9.3 kgs
MATERIALS OF CONSTRUCTION
Coil Construction	Copper voice coil
Coil Former	Polyimide former
Magnet Composition	Ferrite magnet
Core Details	Vented and extended core
Basket Materials	Die-cast aluminum basket
Cone Composition	Paper cone
Cone Edge Composition	Cloth cone edge
Dust Cap Composition	Solid composition paper dust cap