Info on Building a Simple Platform

[Fors*]

I am a real novice when it comes to the construction end of HT, so please bare with me. I am interested in building what I believe is going to be a rather simple platform that is to serve the purpose of supporting my loveseat recliner so my single LFE buttkicker can be maximized. I have done some research and I am going to list what I believe is the simpliest platform. I am sure I will leave some things out, but this is what I know of, so far. Limited budget too, (not sure how much, this is why I am asking in this thread to find how much $$$ I absolutely need in order to get this done...) I understand there are a lot of other bells and whistles I could be adding, but I just want a platform for my couch to maximize my buttkicker:

Recliner is 5 feet wide and about 4 feet in depth when reclined:

1) 7 or 8 2X4's for the width of the frame (length recommendations?)
2) 2 more 2X4's for the front and back (length recommendations?)
3) Auralex U-Boats (Not sure how many I need with these dimensions?)
4) Plywood (Dimensions? Can it be 2 pieces or should it be one? - Limited doorway space down the stairs to the basement...)

Anything else I absolutely need to maximize the performance of my buttkicker for this platform......?

What I listed is what I think I absolutely need to make the buttkicker do its job right. I realize I could add additional things for the acoustics, but this room is "not ready for prime time" in any real way for the best acoustics (alot of open space, lack of concrete walls, etc....)

Any and all assistance from the blu-ray experts is appreciated....thanks in advance!!!!