Crossovers and PA System Control
Back in the day, PA system control and drive was done with separate rackmount units for your active crossover, system EQ, system compression and limiting. Thesedays however, many manufacturers are producing an all-in-one solution for this application. DBX has their DriveRack series, while BSS, XTA and Xilica are also excellent for system drive solutions. Of course, if you're after a simple active crossover (stereo 2-way or stereo 3-way), DBX is always a good place to start.