I've not tried this and probably won't but picked up this tip in case your seating position is in a "null" bass position in the room - ie. you don't hear the bass (or feel it)
PLace the sub in your SEATING position, run the sub and walk around the room until where you hear/feel the bass the loudest.
Put the subwoofer there.
PLace the sub in your SEATING position, run the sub and walk around the room until where you hear/feel the bass the loudest.
Put the subwoofer there.