t8kc - I agree with you... I was kinda grasping at straws for an explanation. Maybe it's because my room, while large, is oddly shaped, with a ~10 ft. niche where the speakers are. Maybe that helps their efficiancy? So, I guess it would be my room, not yours, that could account for the different results with similarly rated amps. I don't know, just guessing. And I see from the photos that there is no reason not to place anything above the cans. And, yes, mapman is correct about the tweeter facing forward, and non-directional frequencies, so again, I stand corrected. Although, placing any significant weight directly on top of the grill caps is probably not a good idea, and it is not really flat, anyway.