Amping existing 6x9s VS getting sub+amp?

Question

I'm trying to round out my car stereo system, and i currently have a sony head unit, pioneer 4x6s (20 watt rms) in the front doors, and kenwood (90 watt rms) in the back.. all running off the sony head unit at about 20 watt rms. My system sounds tiny and underpowered, with little bass, and becomes distorted at high volumes. I'm considering purchasing a two channel amp (100 watt rms), and hooking it to the 6x9s VS getting a sub to add bass and using the existing speakears for highs/mids.

The 6x9s are here http://www.bestbuy.com/site/olspage.jsp?skuId=8287515&st=kenwood+speakers&lp=5&type=product&cp=1&id=1172881563579

would they supply enough bass with an amp to keep me happy or am i going in the wrong direction? also, im trying to spend as little money as possible, and im not exactly looking to set off car alarms, just rattle the interior a bit. :) any responses appreciated. also, if i got the amp for the 6x9s, should i attempt to go the DIY route and hook it up myself, or pay..

Answer 1

amp and sub.leave the6x9s alone. y will just blow them

Answer 2

i would a  small sub and amp to get the lower end of the bass that 6x9 can not produce. addin a amp to 6x9s would over power the front speakers

Answer 3

Add a amp&sub. One of the biggest gains in sound quality comes with the addition of a sub-woofer because adding a sub allows you to remove the bass that is sent to your smaller speakers so they can produce mid&high loud and clear without interference from low frequencies. Right now your small speakers are limited because the bass interferes, you will still have the same issues with 6x9s.

Do it yourself, if you know how to jump start a car you should be able to hook up a system. If you need help just ask more questions.