Raise my subwoofers off the ground approximately 12”?

I have a pair of JL Audio F113V2 subs and in my former home (in a room with terrible bass) I built some stands using 4 x 4's and sturdy metal hardware, and that reduced the boominess in that room.

I'm about to move into a new home and if I don't need them, will probably try to see if someone else can use them.