A good quality electronic crossover with settings for 2 way stereo or 3 way mono. There is an additional subwoofer output which can be adjusted from 10Hz to 235Hz.An electronic crossover will be wired inbetween mixer and amplifiers, this will allow the correct frequencies to be sent to the correct amplifiers then to the correct speaker cabinets. This will mean that bass frequencies to bass amp then to bass speaker cabinets. Each output has gain and mute facilities, this will help setting and adjusting each output. All frequencies can be adjusted with rotary knobs so there are no complicated menus. Other features include phase reverse switch, XLR inputs/outputs, illuminated switches and low cut filter.