The Eminence Impero 18 Inch Replacement PA Speaker plays extremely loud and low in compact vented designs. Advancements include a 1/2 inch thick by 7. 5 inch diameter machined top plate, one piece machined T-yoke, and a 4 inch deep wound fiberglass voice coil. These features combined with an ultra-linear long-excursion suspension and bumped motor assembly allow the Impero 18 Inch Replacement PA Speaker to move serious air, generate serious SPL, while handling tremendous amounts of power. The 18 inch Impero rated at 1, 200 watt continuous / 2, 400 watt program power, has a frequency range of 39 Hz to 820 Hz, and is suited for full-range three-way boxes, bass guitar boxes, and small subwoofers. Available in 4 or 8 ohms.