What would be better for SQ with this amp Alpine MRP-m650

600W x 1 @ 2 Ohms

400W x 1 @ 4 Ohms

One or Two subs???

 

Really depends on your car and the sub. If you can't hear one single voice coil sub very well because of your trunk, then you can always throw another in there to try to increase the volume without overpowering your gain and making your signal distort. Using a dual voice coil sub, you can wire it to take advantage of that 2 ohm power load and provide more clean power to the subwoofer as well.