Ok so I know there are a lot of explanations of what a ohm is and how it works but i just don't get it. I also would like to know how many ohms in an amp I would need for two 400w rms 800w peak subwoofers. I see all these amps on amazon that say things like 4 ohms stable @ 800w but would that power my two 4 ohm subs at 400w each? If you could also a nice explanation of what a single voice coil is vs a dual voice coil. Thank you in advance!