Vandersteen 2wq's are available for under $2K for a pair, but you need the crossovers ($800/pair). Just follow the directions and you'll have the best integrated subs you will ever know.-And, they will perform without issue for years.
Bob
Subwoofer recommendation
Von Schweikert Vr-8's
There are giant, They are rated to 20hz but due to room I don't think they get there.
Looking ta around 2K used
Something that gets out of the way unless I want it to and can rock the house.
Looking at Rel t9X?? Rythmic, ect.
Want to do this once...