Hi BigHonu,
No, the driver does NOT have to face you. It will make no difference at all if you use a crossover frequency of 80 Hz or lower. My Axiom EP500 is at one end of the couch, with the driver firing towards the wall on the other side of the room. If you use a higher crossover frequency (100 Hz and up) you should put the sub with your main left and right front speakers, as some bass from the sub will be directional.
As long as the port is a 4 to 6 inches away from the wall, you'll be fine. I would not face the driver into the fabric of the couch, however.
More important is the relative position of the subwoofer to nearby boundaries--not just a wall but a corner. The closer you move a subwoofer to any boundary (wall) or corner, the greater the reinforcment of low bass, corners providing the greatest emphasis at the risk of sounding quite "boomy". Conversely, if you move the sub away from boundaries, you'll get less boundary reinforcement of low bass, which may make it smoother.
Of course, the sub crawl is an excellent method to determine the best place for a sub.
Regards,
Alan
