RE audio's xxx line of subwoofers are insaneimg src=
http://reaudio.com/images/woofers/xxx_thmb.jpg>
12"specs...
Electrical Q Value -Qes: 0.46
Mechanical Q Value -Qms: 3.29
Total Speaker Q Value -Qts: 0.404
Free Air Resonance -Fs: 21.00 Hz
Equivalent Compliance -Vas: 74.0 liters
One-Way, Linear Excursion -Xmax: 54 mm
Efficiency -SPL 1W/1m: 83.76 dB SPL
Effective Piston Area -Sd: 480 cm^2
DC Resistance -Re: 4.2 ohm
Nominal Impedance -Znom: Dual 2 ohm
Thermal Power Handling -Pe: 2000 W
Force Factor -Bl: 18.16
what all that means.. is with a class d 2500 watt amp rms thats bridged for 2ohms with just about any kind of box u can want.. its gonna blow your seal off your windshield