Question on New System

ALPINE CDA-9855 CD-MP3 RF P3 12' Subs (2x) RF P8002 2400watt 2-Channel Amp RF P4004 4 Channel Amp This system, along with my new RF components are all working fine, except for one slight problem. The 12' Subs do not produce that much bass, I have to put the bass boost all the way up to hear it (with my old system my RF HE2 were loud and very clean). We have found that when we installed my friends 10' Sony Explodes, the bass was loud clean and hit extremely hard. So it does not seem to be the amp unable to give the subs power. Lastly we are running the, subs at 2x4 Ohms (8 total). Still, it is hard to hear the bass. Does anyone have a few suggestions with what could be the problem?

i think its you sub wiring can you give me more detail about  how you have them wired  your subs are dual 4 ohm  if that is correct you could get a total of 1 , 4 ,or 16 ohms and if you hooked up those sony subs which are single 4 ohms you would of been at 2 ohms ? do you have the amp bridged  1974 ford pinto 4 15" punch Z power punch bd 1001 pioneer DEH-6700

 what you want to do is wire the subs +to+ and -to- and run the amp stereo then you will be running the amp at 2 ohms and you should get the results you are looking for1974 ford pinto 4 15" punch Z power punch bd 1001 pioneer DEH-6700

We tired rewiring them

We set it to 4 ohms cause that is what the particular subs are suppose to be used at...don't understand why you would run it at such a low ohm rating.