the 3 subs I have are all different ... have been trying different models to decide for myself the bang for the buck of subwoofers. my first sub as can be seen in the other thread is the velodyne dls-5000R (15") second one is the axiom ep500 and a third one coming is the velodyne DD-18 (hence my reason for not needing dual subs on LFE duty)

during my experimentations, I have also discovered that using the first 2 subs NONcolocated have resulted in negating what low end the axiom has ... (room measurement have resulted that instead of the 18hz extension, it followed the crappier 23hz extension of the velo) this is solved by colocating.

setting the left and rights to large however will take too much work out for the velo DD-18. (hence deciding between the surrounds or center) - I cant assume performance will improve using dual LFE's (axiom and DD) until the DD actually arrives.