I am looking to replace my Definitive Technology Supercube 6000 with a new subwoofer to augment my Fyne F-702 speakers. My listening room is about 13 x 22 ft with 8’ ceilings and an 8’ opening to the dining room to the left of the listening area. I try to avoid major products made in mainland China—in spite of their at times very good quality, and I have narrowed the brands down to Paradigm, Vandersteen, and JL Audio, specifically, a single Paradigm XR11 or dual Defiance X12s, the Vandersteen Sub Three with “required” crossover, and the JL Audio Fathom f110v2. My budget is about $4K, with the XR11 and Fathom right at that price, the dual X12s at about $3K, and the Vandersteen with required crossover at about $5300 (including two crossovers, as they are sold in pairs). I may be able to audition the Paradigms and the Vandersteen; a friend has told me the room correction software with the JL Audio sub is way behind that of the Paradigms. In light of the excellent advice I have received in this forum, I wonder if folks out there have had an experience with these subwoofers and what they might recommend. Many thanks.