Is it possible to get an amp to power one 12" sub in back and 2 5 1/4 components in the front? I think the sub is around 150 RMS and components are about 120 RMS. What kind/size amp would be needed to power this? Also, I suppose this would overpower the 3 way 6x9'* in the back??

i had an 3/5 channel xtant amp before. xtant 3300x
powered a type r 12 and boston rm9 6x9s perfectly
it was around 400 watts to the sub and 60 to each 6x9
only thing is that amp ran for $1000 brand new

xtant now makes a 603x that replaces that model

i think there is a way to run tri mode on most 4 channel amps though

If you have a 4 channel amp all you have to do is run the sub off one and bridge out the other side which means running it from both + posts to run your other exponents.

I did this with a 4 channel pioneer and it did just fine I got around 300 to subs and had plenty of power to run all the interior speakers. 300/4 so about 75 to each speaker.

Don't mean to sound like I"m steppin on anybodies toes.. but more of an enquisitive like to learn more question.. so I hope no one gets offended

But if you run both + the one speaker.. in a sense you're running parallel and thus would still get the same wattage per channel going to the sub? But if you run + from lets say the left channel and - from the right channel ( and on older amps.. you would actually need to put a jumper from left - to right + ) wouldn't that be in series and increase the wattage then? Would this change or affect the load ohms? Or any other problem? Just wondering from an electical view.. that'* all.. enqurin minds wants to know.

Well most new amps require it to run from both + posts because you should be running them in series. Im not accually sure why this is but I seem to hit more peak power from this rather then from running + on one and - on the other. Its recomended by most manufaturers to run this way and also I have measured and accually have proof that this is the way to go.

Thanx russianpolarbear... that'* what I wanted to hear...

So let me see if i understand -
You only use one of the channels for the sub. Then you are left with three channels for 4 other speakers. To get back to 4 channels two are bridged/ run in series?

With a 4 channel amp, use the front channels, L&R, for the 5 1/4" component set, and bridge the rear channels L&R, following the manufacturers instructions, for the sub.
A good 4 channel amp with a rating of 40 watts/chan RMS into 4 ohms will put out about 160 watts, X2, when 2 channels are bridged into 4 ohms.
The bridged channels see half the impedance that they are connected to. A 4 ohm load is seen as 2 so don't put too low an impedance on the bridged channels. Again follow the manufacturers reccomendations.

Beat me to the explaination damn it Silver