Acoustical Solutions or Auralex LENRD bass traps

You may want to check out the following links. If you're in to simple DIY you can equal or better about anything commercially available.

http://forum.studiotips.com/viewtopic.php?t=536

This one illustrates the relative cost of room treatment normalized to the effectiveness of the absorber.

http://forum.studiotips.com/viewtopic.php?t=534

http://forums.studiotips.com/viewtopic.php?t=535

http://www.bobgolds.com/AbsorptionCoefficients.htm

TONS of info here for those so inclined.

Shad...There is a ton of info out there, but I think the basics as as you've described them are pretty close to the mark. Ethan Winer is a good source & everything I've read from him keeps pounding on the same basic approaches.

However, not being a slave to dogma...Personally, I'm partial to oxygen & carbon dioxide-free OC 705 that's faced with virgin long-fiber, acid-free kraft paper...framed in old-growth bald cypress, stapled together with 5-9 silver staples & reinforced with glue from long-maned, in-season mongolian mare. Each panel is then loosely wrapped in homegrown, homespun, and unbleached cotton duck. The difference is subtle, but they really open the soundstage up once they are broken in.