> These speakers have tremendous bass output, but how do I get to hear it? <
Your room is very close to the same size as my living room, so I know what it sounds like and what it could sound like. First, it's not clear from your post how you're oriented, but you should set up so the speakers fire the longer way down the room. Then set the listening position so your ears are 9.1 feet from the front wall you face. If you'd rather not be so close (though the sound is more accurate close) you can sit with your ears 9.1 feet from the wall behind you. The 9.1 foot distance is based on the "38 percent rule" which is the most favorable compromise for modal peaks and nulls. However, you'll still benefit enormously from bass traps. One in each wall-wall corner is a minimum for good bass.
--Ethan