Like in any healthy relationship, your car and your iPod need to cultivate good communication. One of the most popular ways of transferring the sound from an iPod to the car radio is to use an FM transmitter. These translate the iPod's information into an analog signal, which the radio then picks up. You can designate a frequency for it -- preferably a weak one, which may be hard to find in a big city. Just tune your radio to that frequency and voila! You're listening to your iPod in your car.
All FM transmitters aren't created equal, however. Some have a feature that seeks a good frequency automatically. What's more, sound quality may depend on the efficiency and length of the transmitter's antenna [source: Kensington]. A few models use the charging cable itself as an antenna for better quality, while other FM transmitters are completely wireless, small and very portable. If this is the case, they'll have poorer-quality antennas. And without a charger, they'll sap power from the iPod itself, shortening the device's battery life.
For the best sound quality from an FM signal, experts recommend an FM modulator that uses wires to connect the car's antenna and the radio [source: Cabell]. Using one of these involves removing the radio -- a more complicated process than hooking up typical FM transmitters.
While FM transmitters (especially wireless ones) are simple to install and use, beware interference and hissing sounds. For better sound quality, you can try using an adapter, which we'll talk about next.