I am very happy that that solved your problem however, I can't really understand why!
The M80s were set to large so playing full range. Even if the crossover was set low to 40Hz, the M80s will play down to 25 Hz or so and the EP500 from 40Hz down. Now with the new setting, the M80s will play to 80Hz and then the sub from 80Hz down. If the system is calibrated properly, it should be no difference in volume by the 20Hz-80Hz being played by the sub vs by the towers.
Can someone tell me what am I missing?
