Roll off 18db/oct at 20hz.
I have a mate of mine down here that owns a Funktion1 rig and I cut my teeth on infra-bass, so I have a thing for exploring what can be done done in the nether regions of sub-space. Tricky territory but I reckon its fun, just dont over crowd it or expect most systems to translate the music very well in that area.
I dont produce for vinyl as it has limitations I cant live with.