You're no longer using it as a, "SUB." 200Hz is close to a piano's Middle C(264Hz). BUT- As long as it makes you happy..... You may find this of interest: (http://greenboy.us/fEARful/frequencytables.htm)
Sub best at high crossover?
I am wondering, is my ears deceiving me, or is the Velodyne DD-18 actually sounding better, when I defeat the crossover (by setting it to max, 199hz), and turn the volume some steps down? This is in a fairly large room, with the sub well positioned, augmenting full range speakers. I hope others will share experience.