You can have extension, but at the expense of output. In that room, you will want output first. If you are really interested in subsonic bass, the best way to go really deep is a bunch of sealed subs. The gradual rolloff plus room gain can get you very low bass, sometimes as low as 10 hz. But if your budget is strict at $2k, I would go for a Rythmik FV15HP or SVS PB13 Ultra. If you can swing an extra thousand, I would go for some sealed 15"s like some Hsu ULS-15s or Rythmik F15s, and stack them in a corner, a setup like that would dig to subterranean levels.