well for 2 sa12's i would get a 1200-1500 rms @ 2 ohm. people in my other thread and at my local shop said i would need to upgrade my electrical system. as far as my goals. just want a box so i get some nice bass without cranking the volume knob, have having the music blow out my ear drums. also, 90% of the time i listen to rap, the other 10% is partyboy mash ups and dubstep remixes. space isnt a problem, i know for a fact that i have room. i have no clue what vas, qes, and fs are. care to explain please? Drivers don't require any specified amount of power, and they will perform just fine without meeting their RMS numbers. So yes 1500watts on both drivers will be louder then say 500watts on both drivers, but it doesn't mean the latter wouldn't be louder then a single driver, or sub-optimal in any way. Your going to want an enclosure on the larger side for increased efficiency, and better low end response. Vas, Qes, and Fs are from a set of specifications known as Thiele Small (T/S). Each represents some characteristic of the driver, and all together allows for enclosure modeling among other things. If your that interested in learning about it then buy The Loudspeaker Cookbook, otherwise: copy the t/s specs from the Sundown site into either previously mentioned apps, and let them do their "magic."