Originally Posted by Kevin_Hsu
Given where you're seated in that room, I believe you may very well be able to go with a single sub for that room. The benefit is that you are seated up against the back wall, so that tends to give you a good amount of boundary gain at your listening position and you tend to not get as strong of nulls versus when you're seated out into the middle of the room. For the single sub I would just keep it out in front and maybe try to place it on the inside of the right speaker (between the right speaker and entertainment center) to see if that gives you a better mid-bass punch at your listening position.
I wanted to clarify that the MLP is actually the center seat on the sofa, not where the figure is shown in the image, in case you thought that's what was being implied. Does that change your advice? What are your thoughts about putting the single sub in the front left corner, where the guitar amp is located?