Really, the TH900 is almost certainly aeons ahead of the LCD-2. Orthodynamics can't deliver the same amount of raw slam that a dynamic driver can, and the TH900 measures FAR better than the LCD-2. Even the transients (which orthodynamics are known for) are far better on the TH900:
The LCD2r2 30Hz squarewaves are textbook perfect dude. What the heck are you talking about?