Deniz,
I dont know. Did you try running these tests using a no sub configuration? then we could at least compare the digital speaker to analog speaker setups more accurately. also when the mains were lower, are you saying they are lower than the surrounds and then the lfe channel was even lower than the mains?

Best regards,
Jerry
Main System: 861v6, DSP8000s in corners, DSP7000s Center and Sides, 1-9 humans.