I have a pair of 7seIII's in my dining room. They have a bit of a boomy low end (not to the point that it's offensive to me), and the high end isn't as bright as my totems, nor my Infinitys. If this is what you're experiencing, I think that may be the Paradigm sound . . . at least for the 5-7-9 se line up.
Sorry, I can't help with how to brighten them up.
Sorry, I can't help with how to brighten them up.