how to setup this system

im sorry but i dont understand what this means whats the difference between, if they are capable of the 2 ohm per channel load, as opposed to not being capable

On one of your pictures it states a 2Ohm load.  On the picture where the woofers are connected, it says minimum of 4Ohms.  Give me a minute, I will do some research and get back to you.

I can find no on-line information about that amp.  I can find info on the xm5046, but nothing on the 42

You said that you were using each amp to power each sub before? Correct? Chances are you are not going to be able to get it as loud as you had it before. It sounds like you did not have the other speakers in your car amplified either. Now you door and deck speakers are louder, but you subs are getting less power. You might benefit from getting a slightly larger amp for your subs. Also, what I am an idiot was talking about in regards to Ohms. It is also known as resistance. Basically, the less resistance you have the more watts you have. Which means more volume. Also, with less resistance comes more heat. The higher the ohms the more stable the amp will be. In the diagram, it says that you have to have minimum of 4 ohms. If you go less than that the amp may run hot and go into protect mode. Some four channel amps can bridge both sets of speaker inputs. So if you check above them it may say bridged and arrows pointing to a positive input from one side and a negative on the other. You may be able to do that and you should double the power you are getting now. Only due that if it says bridged, because it may not be capable and it may make it overheat. Hope all that is helpful! lolMECP Advanced

Make your life easier and buy a DMM.

oh i am an idiot, its a 4Z not 42, thats probably why you couldnt find it so your saying that if i bridge the 2 subs from the one amp that they should run better then how it is currently setup?

Only if that amp is capable. It would say bridgeable in the specs.MECP Advanced

Make your life easier and buy a DMM.

okay so i bridged the subs, and it didnt make a difference, so is there any other way i could set it up? or should i just buy another amp to power the sub..

In order to get all you can out of these amps, you need to connect them just like the following picture.  Connect the Front RCA's and the front speakers to the 2 channels furthest away from the power input connections of the amp.  Split your SUB RCA cable (separate the left from the right), and connect one of those to the White RCA jack of the 2 channels nearest the power wires of the amp.  Bridge one sub to those 2 channels.  Just as the picture.  Connect the sub's positive wire to the left positive terminal.  Connect the sub's negative wire to the right negative terminal of the amp. 

Duplicate this for the rear speakers and the other sub.  One sub is to be bridged on 2 channels of one amp, and the other sub is to be bridged on the other amp.