It is very common for the EP500 and EP600's to be very low on the gain setting on the receiver and/or sub to achieve a calibration with the other speakers.

Most of us have the sub gain very low, around 6-7 o'clock, and the receiver gain in the -6 to -8 ranges.

M80s VP180 4xM22ow 4xM3ic EP600 2xEP350
AnthemAVM60 Outlaw7700 EmoA500 Epson5040UB FluanceRT85