Do i need a capacitor for my sound system?

I have a base model 1996 Chevy Camaro. I have 2 KFC-W3012 Kenwood Subwoofers in a Dual sealed enclosure. I have all Kenwood KFC-1693PS Speakers all around. I have a 800 watt Kenwood KAC-8403 Four channel amp for my interior speakers. I have a 1800 watt KAC-9103D for my Subs. I will be hooking both of these up. I also have to sony xplod tweeters I installed in the rear running off my Jensen linear phase UV9 headunit. My amps are a total of 2600 watts. I haven't hooked it all up yet but I'm for sure my lights will be dimming and it will not be good. Could I just use a capacitor? If so how many farads. And what's a good brand? I realize upgrading my alternator would be a good choice but if I don't need to put out all the cash for it and then doing the "big 3 upgrade" I would prefer not to. Any ideas? What could I do? You can answer here and you may also email me at iskateboard716@hotmail.com. Please help me out. Thank you