What you're noticing is just some cheezy "bass reflex" and "3D stereo expansion" that Creative puts into the Live drivers to make them sound better. You can get the same thing by turning on SRS TruBass and WowEffect in Windows Media Player 7.
Creative has been using some really low tricks to keep people buying their high end cards. As a near-monopoly, they're almost as worthy of scorn as Intel or, perhaps in the near future, nVidia.
Modus