There are three major units in a Car`s Radio system and they are:
* Head unit – generally a high end home audio system consist of a radio tuner, a CD player, Preamps and amplifiers click here to learn more about autoradio android. But since place is a constraint in a car, all these had to be shrunk and put into a single device which is the head unit. So it is a multi-faceted unit performing different functions but the two major operations it performs predominantly is controlling the entire unit and generating audio signals.
* Amplifier – the amplifier is supported by a preamp that gets the audio signals from the head unit first and prepares it to be sent to the power amplifiers.
* Speakers – These amplifiers strengthen the signals received so that they can drive the speakers.