Wow, Kevin, good luck with those. During the advent of your second sub, why don't you try moving your current sub out of the corner? That'll smooth that curve out. My bet is that even with a second sub, you'll be moving the first one out of the corner anyway. I tried a corner loaded sub balanced by a second sub and I couldn't find a good place for the second sub to balance the peaks and valleys. When I moved the first sub out of the corner the balancing got a lot easier.