first off, i should say that this forum is primarily for installing computers in cars, though i think i should be able to help you a little:
my response to a PM about a similar question:
Originally Posted by PM question
this deals with the speaker resistance.
speakers use a round coil of wire-- called a voice coil. to create it, a single wire is wrapped around the voice coil part many times.
the amount of times the wire gets wrapped around the voice coil determines how high the resistance is-- the more wire that gets wrapped around, the higher the resistance. the resistance to the power flowing through the wire, is measured in ohm's.
in your case, your amp is capable of 2ohm loads--or, in other terms, a lower resistance then normal.
no amp specs will ever say it, but it is always ok to connect a higher resistance then what is stated in the specs.
to answer your question, the resistance that you connect to the amp is determined by the speakers-- there are no amp settings to change.
but to further explain-- every setup has a advantage and disadvantage--for instance, you have 3 speakers, a 2 ohm speaker, 4 ohm speaker, and 8 ohm speaker.
the 2 ohm speaker will be the loudest, but will sacrifice clarity--you will be able to hear the music, but it would lack some details.
the 4 ohm speaker will be a little quieter, but will be have a more detailed sound then the 2 ohm speaker.
the 8 ohm speaker will be even quieter, but will have much more detail then either the 2, or 4 ohm speakers.
to further add to this, each step up in resistance will allow the amp to run cooler-- a 4ohm setup will run cooler then a 2 ohm setup, etc.
as you can see, each speaker setup has a very specific advantages and disadvantages.
and to even further confuse you, connecting speakers in series/parallel will change the resistance the amp sees.
connecting two 4 ohm speakers in series will have a 8 ohm load at the amp.
connecting two 4 ohm speakers in parallel will have a 2 ohm load at the amp.
again, each has a advantage-- the 8 ohm layout will boost the sensitivity, and make some sounds a little clearer, but the 2 ohm layout will be much louder, at the cost of clarity.
that answers part of the your question, but the other part of your question deals specifically with the power that the components would receive:
1. the wattage ratings on sub's denote the amount of heat they can dissipate-- every time you pass power through a wire, some of the power gets lost in heat. the average power rating of a sub takes this into account-- the better a sub's voice coil, and other components can get rid of heat, the higher the power rating.
2. 'more power' while it is correct that a 2 ohm sub will receive more power then a 4 ohm sub, there is a catch--similar to what i detailed in the PM response-- the catch is that the 2 ohm sub will require more power to move the sub clearly-- part of the advantage to the 4 ohm sub is that there is more windings in the magnetic gap, so that means there is more control over cone movements-- a 2 ohm sub, while louder, would require more power to get that same control.
so while on paper, it appears that the 2ohm is better because there is more raw power, there is much more to it..
3. to further complicate things-- you are getting 2 subs-- so to meet the subs power requirements, you need a amp capable of 1200w rms. when you split the output of a amp between subs, the amount of power that each sub gets is halved.
4. BUT!! you can power subs will less power it won't hurt them-- this just means that you will have a little less control over cone movements-- so instead of the sub cleanly 'bumping', it might 'thwomp' more.