Brand new speakers aren't working.......PLEASE HELP!!!

[SpeedDemon G8 GXP]

I installed my Polk Audio DB651's yesterday. I started with the front driver side, then went to the back driver side, then the rear passenger side and then the front passenger side. One by one as I put them in the door I tested the speaker and it worked. Went all the way around doing the same thing. No problems. Put all the doors back together and tested it out. It seemed to sounds good. So today on my way to work I cranked it up pretty loud. All the way up to 40, which I could only do 30 with the factory stuff. Everything sounded ok as as far as no distortion or anything like that, but i felt like it should sound a little better. I then realized that both of the front driver side and front passenger side speakers were not working. Not like a little sound....absolutely nothing. I have no idea what I did wrong. I checked the radio and the fade and balance are both set at the middle so I have no idea. So I'm at a lost for words. I was also thinking that maybe the power output of the head unit couldn't power all the speakers but I would image that with the fade all the way up to just the front speakers then they would work seeings as the head unit wouldn't be pushing anything to the rear speakers. I tried this and still no sound. I also thought that maybe the adapter between the factory wiring and the speaker came loose but they are on pretty tight. You definitely had to put a little force behind it. Also the fact that it's both front speakers makes me think its not that. I am definitely a novice when it comes to audio so I am at a loss for words. I would think if I blew the speakers which I can't imagine I did, the speakers would still at least have some sort of sound coming out of them. I don't know what to do.........any suggestions?????

[SpeedDemon G8 GXP]

So I figured it out. Both of the adapters that are used to connect the factory wiring to the new speakers came undone. The fact that it was both front speakers really had me worried. I just ordered some subs yesterday. 8'" JBL Stage 810. They have good reviews. There nothing crazy but for me it should work. I don't need that hard thump that you would want with rap or that sort of music. Now lets just pray that they fit into the rear deck where the factory ones are.

[MongosG8]

Are the subs 4 ohm or 2.. you want a 2 ohm sub.

[Lunitunz]

Are you using the stock headunit? Where do the new speakers plug into? I want to upgrade the door speakers and maybe the factory amp.