A crossover is an electronic device that is used to send the appropriate signal to the correct speakers or drivers. A crossover dedicates each driver to a particular frequency range. How it works begins with the speaker system breaking the audio signal into different pieces; low frequency, high frequency and sometimes mid-range frequencies. The frequency is divided up by inductors and capacitors and then sent on to the woofer, tweeter and mid-range driver. In summary, the crossover is a necessary device that aids the in-car entertainment experience. It automatically creates sound that is evenly distributed resulting in an optimum performance.