Brand new--they came w/spikes---Don't expect much in bass definition w/o spikes.--Get U some.
As I remember from the manual their setup instructions were "spot-on"--Something like 3 to 3 and 1/2 feet back and sides for unbelievable imaging.--Of course that was for the 3si's---I would also at least try the short wall. My short wall is wider than your 12;wide. Mine is 14.6 wide and that worked well.---(That rear tweet loves proper reflection.)
As I remember from the manual their setup instructions were "spot-on"--Something like 3 to 3 and 1/2 feet back and sides for unbelievable imaging.--Of course that was for the 3si's---I would also at least try the short wall. My short wall is wider than your 12;wide. Mine is 14.6 wide and that worked well.---(That rear tweet loves proper reflection.)