Looking at your situation a bit closer, this is most certainly a matter of expectations. I am pretty sure that sub is pounding hard in that room. I think you were expecting absolutely blinding bass. I don't think that a room mode is primarily at fault here.
If you want to see if that is the case, run pink noise tones like
this one, turn the speaker channels way down but leave the sub channel at its current level, then walk around the room with the sub blasting that pink noise. As you walk around the room, the sound of the pink noise will change, and this is the room modes shifting the peaks and nulls of the room response up or down. If the pink noise tone sounds weak at your primary listening position compared to other locations in room, then the problem is a room mode, but if it sounds as powerful at your listening position as elsewhere in the room, then the problem is your expectations.
But a PC13-Ultra should be able to hit hard virtually anywhere in a 10x10 room. Yes, standing waves will create nulls in some frequency bands in some locations in room, but, for the most part, it should be very powerful. The fact that you caused the dub to emit an odor means that you were running it very hard. Don't do that again because you risk killing the sub and voiding the warranty. To get the sound you want, you are going to need something more powerful. My recommendation, if you can spend a bit more, that still have a small-esque footprint although slightly larger than the PC13, is the
XTZ 3x12. The only problems are it is very heavy and, at $2500, a bit costlier than the PC-13. It is a much more powerful performer than the PC13-Ultra across the board. Something else you can do, if you don't want to spend more than the cost of the PC13-Ultra and need a small footprint, get a couple
ULS-15 mk2s and stack them. That does give up a bit of deep bass in the 16 to 25 Hz range compared to the PC13-Ultra, but would have far more output at 40 Hz and above, where you get that 'punch in the chest' feeling.
