WOW, it seems I hadn't been notified of the multitude of additional responses, sorry...
Yes, My system is actually comprised of a Main box with a High and a Low and an additional subwoofer.
130Hz, well, my subs sound like total crap crossed over that high, very floppy and muddy.
As per the manufacturer's specs, they recommend a 90Hz crossover point at a minimum and it sounds pretty good there but I've found that the system gels a bit better when I move the crossover point a bit lower.
Like I said, I'm pretty happy with my setting, I was just wondering if anybody had any tricks they'd like to share to help me get to the best possible crossover point a bit quicker, that's all.