best sub for spendor S8r

I would like some recommendations for subs that go well with my Spendor. S8e's...price can be up to about 2K used
Depends on the size of your room and how loud you listen. I had paired an M&K 350THX sub with my S8e's. High passing the S8e helped them quite a bit. I used an M&K bass management controller.

Just about any sealed sub should work well. I recommend bass management. The 8" driver will bottom out when pressed.

I'm a fan of SVS and Velodyne, but there are numerous quality sub manufacturers.
REL. Nothing in my pretty substantial experience intgrates as well and as easily.
Velodyne DD-18 or 15----fantastic integration-- Rel is good also, but not as good as Velodyne IMHO