1. Decks – Car stereos cannot function without a deck. A deck constitutes any piece of equipment ranging from cassette decks and CD players to MP3s and mini discs. The deck is considered the glue that holds the car stereo together. The deck controls the overall output of the sound and allows you to control the music being played. All car stereo decks have a minimum 4-channel output for your speakers. If you want more power than what your speakers alone can hold, you may want to consider purchasing an amplifier.
2. Amplifiers Amplifiers provide the power needed to blast the music in your car. The more powerful your amplifier is, the louder the sound system is going to be. An amplifier can have anywhere from 1 to 7 channels. The number of channels in your amplifier is the number of speakers you can hookup in a series circuit.
3. Speakers Speakers are where the sound from the stereo is emitted. Different types of speakers are designed to produce different frequencies. Higher frequencies provide the capacity for more sound and produce a higher level sound as well. The efficiency of the speakers is what will determine how far the sound will travel. If you want the sound to travel far, you will need speakers with a higher frequency.
4. Subwoofers Every high-tech car stereo system should have a subwoofer. Subwoofers complete the sound by providing high efficiency of low frequencies, through the bass. In other words, the subwoofer is the piece of equipment which makes the car vibrate. A subwoofer needs to be enclosed in either a box or possibly the trunk of your vehicle. Keep this is mind when budgeting the cost of your stereo system.
Now that you know the basics of how everything operates, you can ask informed questions as to which components you should have in your car.