Originally Posted by J Stamp
Here are 2 new curves. The blue line is in the same position as the first curve, only with the crossover set to 120. The red line is in a new position. Looks like moving it fixed one dip, but introduced others.
Unless you can find a position that has much better frequency response, you might be a good candidate for a pair of Epik Empires, or if you can up your budget, a pair of HSU ULS-15.
Dr. Hsu is willing to review FR graphs, review floor plans, discuss placement, and make recommendations on subs.
I would be surprised if a pair of ULS-15s wouldn't help your FR.
Of course, first you need to explore all the placement options with your Supercube Reference.
One other thought. Nearfield placement really helps with room modes.
Is there any way you can place your sub REALLY CLOSE
to your listening position? Like right next to or right behind your seat?