Need help designing powered woofers for my 2 channel system

[conscious]

Well the bad weather is approaching and I'm spending more time listening to my 2 channel and really missing the bass. I will finish my new speakers in the next few weeks http://www.soundandvisionmag.com/ide...searchstring=, but know that I will want to add a genuine "woofer" for 2 channel listening. The problem is space. I've got 2 corners right behind my bookshelves but the wife would go crazy if the boxes were big enough to obscure any of our view, or limited floor space. I'm hoping for something around 1 cubic foot (similar to the size of a def tech supercube or sunfire true subwoofer, without the tremendous expense).

My room is about 15x12x8 but it opens to a kitchen/dining room which is 20x15x8 (or 16' high in some places). My goal is to go down to about 30Hz or so,with low THD. I don't listen to anything very loud, mostly acoustic music in the 2 channel (no hometheater), so I'm hoping I can build something that is small enough but gives me sufficient weight to the bottom end. I probably could build 2 woofers if it will help and doesn't mess up the acoustics.

I can't find many projects out there, but here are a few ideas:
http://www.zaphaudio.com/archives.html


Here are a few drivers I've been thinking about. If I've got it right, to achieve low bass with a smallish driver in a smallish box, I need a one with lots of linear excursion and lots of power, right? Maybe:
http://www.adireaudio.com/Home/ExtremisMidwoofers.htm
http://solen.ca/pee.htm (maybe the 21cm XLS driver)

Any thoughts would be greatly appreciated.

[keyser]

you might want to take a look at these. they perform well in a box as small as you mentioned. a bit bigger would ofcourse be better. i'm going for the same unit too. probably in a 100 liter box, tho.

[Cal Weldon]

I have moved this over here to woofers.

Cal