ok my friend is about to sell me his 15 L7 in a custom ported box for $350, including this come a rockford 1001bd mono amplifier, i'm not sure what configuration his voice coil is because i've heard the rockford is only 2 ohm stable, but i've heard its one also, i have an orion 1200d sitting around, so if it is dual 2 ohm vc's, should i use the orion or the rockford....