bass in the room

I am imagining a grouping of bass traps in the hallway. Hmmm...... That should go over well.

You could try the old method of putting the sub where you sit and taking measurement around the room to find the best place to put the sub. It might be in a spot you haven't thought of. Bass nodes are funny things and hard to predict. Also, the walls in your hallway may be reflecting bass in several directions, thereby increasing certain frequencies.

No, actually, I was joking, thinking of what my very patient wife would say to bass traps in the hallway. I would probably be beaten over the head with them! I have found that using a decibel meter and one of the spreadsheets for bass frequencies can help. Smoothing out a sub's frequency responses is very labor intensive. I still think you should try the trick of placing the sub where you sit and walking around to find the "best" sound from the sub. Then, put the sub there. Getting a Radio Shack meter and taking measurements, recording them, using one of the spreadsheets that help you correct the inaccuracy of the meter and moving the sub around is better. Check out the many posts here on Audiogon. I am no guru. Try out all the methods. Remember to have fun!