there was this really awesome head unit i saw that was like 75x4 for like $120 im trying to find that i know i saved the link somewhere
Other than that, for a descent good system, 3Way 6x9 Is always a good idea for the rear
and a component Mid bass and Tweater for your doors is a pretty basic setup.
It may seem like it's worth it to save money and buy something a little cheaper. For now you could simply upgrade your headunit that will give you the most immediate sound qaulity improvment, and anything 200watts and up should be more than adequit.
The next thing on your to-upgrade list should be a larger speaker. Most door speakers are difficult to hear as it is without heavy modification ( dynamat, kick panels etc. ) So just finding a good 6x9 speaker should produce some descent bass and lots of sound.
Now if you're a bass junky. Forget all of that. Go order some subs off the internet. Retail subs are just the most horrid Sound Qaulity i've ever seen. I good subwoofer in my opinion is one with an RMS of a 1000watts and 1500 max watts at 4Ohms.
Then you need an Amp and Box. I would say the minimum you are going to spend on just the subwoofer stuff is going to be $400.
It's a real shame to settle with an "ok" system if you're a die hard music listener.
My cars sound system has evolved from 4 stock 4inch speakers on a 30Wattx4 Casette headunit.
Then a 180 x 4 head unit on 4 kenwood 6.5 inch 2 Way speakers.
(My car was broken into and my head unit was stolen, after that point my attitude changed alot, i wasn't going to hide in a corner and cry, i torn all my speakers out of my car and started from scratch again)
Now i'm up to 6 Loud Speakers running on a 710Watt RMS (thats about 89.7 x 4 @ 4 Ohm )Amp
Not only does it no longer distort but i can raise the volume to deafining levels about 100dB right now without any Subwoofer support.
It's taken 2 years and about $1000 in wasted Speakers, stolen equipment, labor fees and Wire and acessories but i;m finally happy where i'm at.
Ya good luck though
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---Thomas jefferson, Declaration of Independance.
whenever any form of government becomes destructive to securing the rights of the governed, it is the right of the people to alter or to abolish it
---Thomas jefferson, Declaration of Independance.