Like @erik_squires said, there are many possible issues, but if you have a DSP there will be a lot less!
Let us know what you do.
SPL when designing
I am in the process of designing some speaker cabinets with Vituix Cad. Got a question. The main speakers will be driven by a flea watt 6 watt amp. The sub by a Hypex 250 watt amp. Should I try to match the efficiency of the drivers even though the subwoofer and mains will be driven by separate amps. If I want the preamp to be the main volume control (I hate setting the sub all the time), would it help at all?