Would I hear a noticeable difference in sound quality if I got these speakers/deck installed?

Possibilities why kicker comps could sound weak?

• Okay so I have the kicker comps in a pre-enclosed box. They are refurbished, but I don't think that has anything to with it. They are 300 rms together at 4 ohms. I don't expect them to crack the pavement, but they barely vibrate my mirrors. Sometimes it's hard to tell the difference between my stock speakers and my subwoofers. I have the gain all the way up. My amplifier is a alpine 500 rms at 2 ohm and 300 rms at 4 ohm. Me and my dad installed these, first system and installation ever. It's been about a week. Some points of certain songs sound very good, but I expected more. The only thing questionable why it could sound weak is my power wire. If I got a $30 dollar wire kit which had good reviews, and it happened to be poor quality I would only need to replace the power wire right? Should I get a high quality power wire? Or is it my amplifier? Ill post everything I bought with links. http://www.amazon.com/gp/product/B0013TQ6FK/sr=8-1/qid=1284823200/ref=olp_product_details?ie=UTF8&me=&qid=1284823200&sr=8-1&seller= http://cgi.ebay.com/KICKER-DC12-R-SUB-BOX-DUAL-12-C12-SUBWOOFER-4-OHM_W0QQitemZ400148666484QQcategoryZ18805QQcmdZViewItemQQ_trksidZp3286.m7QQ_trkparmsZalgo%3DLVI%26itu%3DUCI%26otn%3D2%26po%3DLVI%26ps%3D63%26clkid%3D5571534401233202015 http://www.amazon.com/GSI-GPROKIT8-Gauge-PRO-Power/dp/B002JCSB80/ref=sr_1_1?s=STORE&ie=UTF8&qid=1284910437&sr=1-1

• Answer:

  having the gain all the way up is a bad thing first off. second get a good 4 gauge amp kit knukonceptz makes real good wire and third wire the subs to a 2 ohm load if that dont work. Well you have kicker lol look into some other brands.