[quote:b4a01944c8="Ramy"]The MPA 6.570 is 5x70 + 1x220 watts. Your sub would need the same wattage on 2 channels.
You could probably run the one 200 watt channel of the MPA 5.480 to both voice coils of your sub by running the voice coils in a series.
EMass could probably go into more detail.[/quote:b4a01944c8]Sheesh, I missed that spec on the 6 channel amp entirely and Ramy is correct, except you can wire the two voice coils together to the single channel in parallel or series in order to run the sub off the new amp.
The primary advantage of the dual voice coil speaker is wiring flexibility. A single dual voice coil driver offers the user three hookup choices...parallel, series and independent.
In a parallel hook-up the drivers impedance will be half that of each individual coil (a dual 4 ohm speaker would be a 2 ohm speaker in parallel.) The advantage to this is that the lower the ohm load, the higher the wattage is to the apeaker. In other words a 50 watt channel at 4 ohm will be 100 watts at 2 ohms. The disadvantage is that a lower impedance (2 ohm) load is much harder for an amp to drive.
A series hook-up results in twice the impedance of each single coil (a dual 4 ohm speaker results in 8 ohms if its coils are wired in series.) The advantage is that an amp that cannot handle a 2 ohm load can be wired up to a dual 4 ohm speaker. The disadvantage is that you lose a lot of wattage. That 50 watt channel at 4 ohms, when presented with a 8 ohm load will only produce 25 watts of power.
Finally, you can wire each voice coil to a separate channel of your amplifier, which can be useful if your amplifier is not mono-bridgeable or if you are bridging a four channel amplifier down to two channels to run your sub. The disadvantage is that the signals must match perfectly and if they do not, you can hurt the speaker.
So as Ramy pointed out - it makes no sense to get the 6 channel version - the 5 (with parallel wiring to the sub) is actually the right choice.
I'm not too sure however what the starting impedance of the stock sub is so I'm not sure if the Rainbow amp can handle the DVC in parallel impedance. If the stock sub is dual 8 ohm - you're safe with parallel - but if it's dual 4 ohm (more likely) then you'll need to be sure that the Rainbow amp is 2 ohm stable in order to do parallel. And being as small as it is - it might not be.
If the sub impedance is 4 ohm per voice coil and the amp is not 2 ohm stable, I'd recommend wiring in series since the Rainbow easily supports 8 ohm loads.
Here's a diagram on the difference between parallel/series/independant sub wiring. The stock sub is wired independantly but could be wired for parallel.
Whatever you do though, do not wire up only one side of a DVC sub, you will damage it.
FYI the 12" single sub in my own ride has dual 4 ohm voice coils. I bridged the two amp channels together (taking + from left channel and - from right channel) effectively making it mono and wired it to the sub in parallel.