Decided to put the subs in 17hz mode and rerun XT32, and then level match with REW and the certified mic. XT32 does a pretty good job, found the subs to be about 1.5db low. SPL meters really arent accurate here.
By going to 17hz tuning I gained 10db at 16hz and 20hz, and kept pretty much the same output from 25-80hz. Gonna be curious to see what the new sub looks like tomorrow after its all calibrated up.
Subs in 17hz tuning
I have a null at 22hz, not much I can do about that right now. All in all, when you take a before and after, I think XT32 does a good job boosting and knocking off peaks where it needs to.