Crossovers for speakers are passive LC-filters of sound frequencies. The application is designed to calculate such filters: low pass filter, high pass filter, bandpass filter, notch filter, as well as correctors of the amplitude-frequency characteristics of the speaker system. Calculation of filters from the first to the fourth orders is provided. Also in the program there is a calculation of auxiliary crossover circuits: circuit Zobele to compensate for the inductance of the coil dynamics and attenuator to reduce the signal supplied to the speaker. The calculation of crossovers is made by the method of filters of the so-called "all-transmitting" type. These filters provide minimal frequency and phase distortion for the designed speakers.