I would say it's cross over points should be just above it's max output mode tuning point (25 hz I believe) and 70 to 80 hz, which ever produces the least amount of localization. But that is just a couple decent starting points by which you should experiment. Honestly I wouldn't want it to even try to tackle the deep stuff, like below 30 hertz. Perhaps, like you said before, you could wire your speakers through the Outlaw so it hits the same high pass filter that they do, providing you are running them as "small" speakers (which you should be anyway, as they only look to extend down to 42 hz before dropping off). Then use its internal low pass crossover to where ever sounds best to you. That is one way of making it into a mid bass subwoofer. I think it is an idea worth playing around with anyway. But, like I said before, the best way to use it in this manner is in near field placement, you don't want this thing trying to compete with the VTF15H. Hopefully the room correction mode on whatever receiver you have can deal with all the phazes, so that cancellation is kept to a minimum.