I guess my question should have been more specific. Would raising the the tuning frequency a bit strengthen the mid-bass? If yes, to what extent can I raise the tuning of the boxes to taste with out messing things up? I made two thick paper ports to lengthen the Theatre 4 ports an inch and another two inches from your design's 3.5 inch length. Both seemed to strengthen the lower midbass a bit with some loss of the lowest bass. The percieved midrange was also affected, not sure if it was better or worse.

Thanks,
Orren