Subwoofer placement is weird. Shortly after receiving it, I was trying to place my sub to get the smoothest sitting position frequency response too. I lugged that 145lb box into about 15 different positions, as I remember. Exasperated, I was just going to center it between the speakers on the same outward plane as the mains and order a second sub, but I saw a spot on the carpet I wanted to clean up first. So I set the sub down in a somewhat random position, off-center about three inches, and closer to the back wall than the mains. I sat down in my listening position waiting for the carpet to dry where I cleaned it, and suddenly the drums on the CD I was playing sounded more natural than they had. I put on the OmniMic CD and measured, and indeed it was the smoothest response below 150Hz I had seen yet. A little EQ on the sub to smack down that 52Hz room mode I have, and some other fine tuning, and the sub has been in that somewhat silly-looking random position ever since. I have used masking tape to mark that position and experiment further, but I've never been able to improve upon mere chance.
