Originally Posted by
paulsaveo
You shouldnt have any issues with upgrading aside from deciding what type of sound you want. I dont know what size spekers your aveo is equipped with, my 04 hatch had 4 inch in the front door and 4x6 in the rear. best thing you can do is shop around check stereo shops, they usually have speakers on demo you can listen to, most basic after market speakers as long as you get the same size as factory will give you better sound and wont have issues mounting them. if you want to upgrade the whole stereo, start with a good head unit, a few places sell wire harnesses that you match to the after market head unit and plug directly into the plag that comes from the stock radio. just replacing the head unit, gives you better ( slightly better) than stock sound. then you can get a decent 5 channel amp to power a sub, front and rear speakers (preferably coaxial for good sound), if you want to go big for not alot of money you can also get a dedicated sub amp, and a mids and highs amp and component speakers for front. it comes down to what you want. if you just want decent, get a good head unit, replace all the stock speakers and get a small sub amp and a small sub. options are endless.