Hey phillihp23, I have experienced some mid level shakers,(can't recall which offhand)(friends theater). From that, and looking over your already nice equip list, I'm going to absolutely recommend 2 more subs. I'm pretty sure his shakers were set up correctly, but I disliked them very much. (I'll confess prejudice toward them in general to be clear though) I just don't think you can substitute pressurizing air with vibes in the couch. They do have their place with some, and I will not begrudge them, and mean no disrespect. ...just not for me. I should ask. Have you ever experienced shakers before?