Well man since it looks like your new to this cause i see you've only posted 4 posts ill help u out some good companys to check out alpine , pioneer , audiobahn infinity , kicker some companys to stay the fuk away from kenwood , sony xplode cause thats all they do is xplode but check out these links
http://www.woofersetc.com
http://www.crutchfield.com
See if any those will help ya man if you got any questions just pm me or post back up on here
with a budget of 550 i dont think he should be looking at the brands you recomended.I wouldent look at most of those companys for speakers anyways.Take a look at cdt,focal,everybody seems to like rainbow speakers around here as well.
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My SyStEm
*Alpine Sps-c172 2 -way coaxial's 250 watts a piece
*Awc12t Audiobahn 12' Subs 500 watts a piece
* In a bandpass box with plexi glass over the top with 4 port holes
*Sony Headunit one of the better ones but will upgrade soon
*bouston acoustic 6x9's 350 watts a a piece
*Amp Still waiting on either gonna be 1200 watt amp or 900 Leaning toward Rockford Fosegate