I am a new owner of a 1993 Lexus LS 400. It has a factory Pioneer cassette with cd changer in the trunk. I would like to order some MB Quart component speakers to replace the factory speakers in the front door. Tweeters tells me 5.25" are the size to get.

I also have a JL Audio 300-4 amp I would like to put in the car. Is the trunk the best place for this? What is the best "bang-for-the-buck" sub to buy? I listen to rock and "old school jazz", looking for quality sound.

Would these upgrades make a noticeable improvement? If possible , I would like not to disrupt the dash of my new car. But if a new CD player (or minidisc) would make a significant improvement , I might go this route. Any help would be greatly appreciated. New to Site, New Lexus owner (had for two full days now)! Thanks, David