The crossover is a device which allows the subdivision of the range-range multiple audio (commonly called "streets"), each of which will power the corresponding speaker. To operate the attenuation of frequencies "unwanted" property is exploited reactive electrical components, especially inductors and capacitors.
In particular, the inductance shows a low resistance (typically one of the wire that is) from 20 Hz to the frequency of intervention, beyond this value will increase the resistance with a progression of 6 dB per octave (remember that is the eighth ' interval between any frequency and its double) up to 20000 Hz capacitor behaves exactly the opposite, its resistance will decrease with increasing frequency with a progression of - 6 dB per octave Let's apply this concept in practice . Suppose we want create a system consisting of a woofer and a tweeter, so we split the audio range into two parts (two-way system) and identify, based on the characteristics of the speakers and the objective of the project, which will be the frequency separation between the two zones (crossover frequency), for our example a frequency of 3000 Hz then adding a series inductance to the woofer to reduce frequencies above 3000 Hz (low pass) and a capacitor in series with the tweeter to mitigate the frequencies below 3000 Hz (high pass).
