The straight answer is they share the same service manual. THe AMP section is the same, the PS section is the same, the Elite has a few extra features. The DAC is the same. Worlds apart is the 59x. ..unless we are talking microscopic scale.
my speakers are around 86db efficient. My movie listening range from -8 to -14, depending on the mix of the movie. I went up to -4 once but it was too loud when some massive explosion came up...have to say it was still clear and clean.
-32 to - 20 for DTV watching. -14 to -12 for DVD viewing. My speakers are around 86-88db efficient. I notice a big jump in the volume between -20 to -14 . And my room is small, 12X 14 with a big opening into an adjacent bedroom 12X 13.