getting more bass out of meadowlarks

I have meadowlark kestral 2's in a 11.6x15x8 room with the speakers firing down the long wall, pergo floors, windows on one side covered by curtains, small area rug and for now pillows in the corners behind the speakers. At the end where the speakers are firing at there are french doors that open up. My question is....the bass is about 40 to 50% fuller when standing oppossed to sitting, what gives? By the way the speakers are 25 inches from the sidewalls and 19 from the rear wall, the kestral 2's are front ported, someone help?! Thanx!