If´ you thinking for a feedback destroyer, the you must think about the Sound system. I use an dbx Driverack 260 for the Front. But when the Feedback destroye is in the GLD, so i can place the drive Rack by the Amps. In this time i have placed it by the GLD. So in need 6 ways to get the Output signals to the stage amps. If i have a delay Line one Amp is placed by the Mixer.
But if i can pair for example the Main Out, st Mtx and the Stereo Mix and have a posibility for crossover, so i dont need a crossover. If have no fixed crossover System. Because i have different Events. Sometimes i need Monitor Boxes on Stage, so have not so much possibilities for FOH. I can drive by 2-Way or 3-Way Speaker System. It´s an open System. I´ve 18″ and 15″ Speakers, they have diffence Frequeny Spectrum in the high Frequences.