EAW 804064 Speaker 18" 8 ohm Made in the USA by Eminence. The Eminence OMEGA PRO-18A is an 18" woofer recommended for professional audio installations as a woofer in vented enclosures. The OMEGA PRO-18A is also perfect for horn loading and scoops. A member of Eminence's Professional Series, the OMEGA PRO-18A sports a strong, lightweight cast-aluminum chassis. Aluminum doesn't conduct the magnetic field out of the gap, thereby raising the motor strength and lowering the stray magnetic field. Eminence coats the chassis and all metal components with a robust epoxy-acrylic finish using their proprietary e-coat process. The thickness of the coating is controlled to within 0.001" - critical when working with close-tolerance transducer motor designs. Front and rear sealing gaskets are then added to accommodate front or rear loading. If you want a great woofer for your installation, you've found it - the Eminence OMEGA PRO-18A. Specifications : Nominal Basket Diameter: 18" Nominal Impedance: 8 ohms Power Rating: 800W; music program 1600W Resonance: 25Hz Usable Frequency Range: 40Hz-800Hz Sensitivity: 97dB Magnet Weight: 109 oz. Gap Height: 0.37" Voice Coil Diameter: 4" Resonant Frequency (fs): 25Hz DC Resistance (Re): 5.2 Coil Inductance (Le): 1.67mH Mechanical Q (Qms): 8.18 Electromagnetic Q (Qes): 0.32 Total Q (Qts): 0.31 Maximum Linear Excursion (Xmax): 4.8mm Coil Construction: Copper voice coil Coil Former: Polyimide former Magnet Composition: Ferrite magnet Basket Materials: Die-cast aluminum basket Cone Composition: Paper Cone Cone Edge Composition: Cloth cone edge Dust Cap Composition: Solid composition paper dust cap Net Weight: 25.2 lbs We Carry A Full Line Of RCF, Celestion & Eminence Speakers & Drivers