Audio Systems: adding speakers, music prefrence, ported boxes

Question
a sub
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The text above is a follow-up to ...

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How would i go about adding speakers to my 03 jeep liberty
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adding what?  more speakers to what's already there?  tweeters?  subwoofers?  what?

Answer
well you need an amplifier that has high level inputs since your factory stereo in the jeep doesnt have RCA outputs. you'll need to pick a sub that's right for you and you'll need a sub box that is right for your musical prefrence and space considerations.
Ported boxes are good for rap and deep ringing bass, they are larger and more dificult to build. sealed boxes are good for puncy beats like techno and rock, they are smaller and easier to build.
I cant really recomend anything withought knowing your budget, music prefrence and space considerations (measurments would be nice) then I can recomend something and tell you how to hook it up.