The head unit is the source for the musical signal, whether it goes straight into the speakers, into an equalizer, or into an amplifier. If the signal is distorted or noisy, that is what you are going to hear. Installing an aftermarket head unit is almost always going to give you a cleaner signal (and more output) than a factory radio...not to mention tons of more features. It is important to make sure that the install is done correctly, though. It doesn't matter whether you drive an old work truck or a nice new vehicle, installing a deck doesn't have to be a big pain or a big expense. A lot of shops charge a flat rate to install a deck, no matter whether it takes 10 minutes or it takes an hour. (I know that doesn't sound fair, but it happens. I've done installs in less than fifteen minutes that the customer got charged full price on.) By learning the basic principles of wiring and sound system design you can choose and install your own unit and save money at the same time!  Plus, the aftermarket decks will give you a lot of options, like the ability to easily add amps, CD changers, satellite radio, and more. If you want to learn to install your own head unit, just click the link below for more information.