There's nothing quite like the sweet sound of your favorite music coming clearly through your car's audio system. Unfortunately, the stock speakers in most older or inexpensive cars really are nothing quite like that. Unless you happen to get a new car with expensive factory audio upgrade, you're forced to listen to tinny, crackling distortions that drive any music lover nuts.
To get a complete stereo system upgrade worth paying for, you normally need to spend a few thousand dollars to replace everything from the head unit, the power wiring, speaker wires and speakers. And of course you would be adding aftermarket amplifiers, speaker enclosures and other accessories.
You can get a huge improvement in sound just by replacing the factory speakers that came with your car. The cheap speakers that come with most cars are made with the lowest quality material and construction methods to keep the costs down.
Even inexpensive aftermarket speakers will sound better than these. At the lowest end, an aftermarket speaker will have better quality cones, domes, and wiring. If you can spend a little more money, you can get into some more exotic materials such as carbon fiber or specially designed plastics.
Going up one more step, you can get speakers designed for stock speaker replacement that will have a special configuration that puts two speakers, typically a mid-range and tweeter, into the same space as a single speaker. And if you have a compatible vehicle, you can even get tweeter and mid-range speaker kits that have the tweeter in a separate enclosure for you place in an appropriate spot in your car. By replacing the speakers first, you're able to enjoy better sound immediately while you take the time upgrade the rest of your system.