So I may be living in the 90's, but I've taken a liking to Dave Matthews lately. Most of his stuff sounds just great on the SDA's, and it's very full-range and well composed music.
Also, I've been listening to Muse quite a bit. Most probably haven't heard of them, as they're a British rock band. A lot of their stuff is harder.... I usually listen to it if I want something loud and powerful (typically on my way home from work in the car).