Originally Posted by longfinger
A side story: We had a drummer audition for my band this summer. He played loud and did not know how to play soft while keeping intensity. We did not take him. Later on, we had a drummer come in and coach us, a guy who taught drums at the University level, he played with power, drive and intensity at a very low volume. All this on a crappy kit that we have at our rehearsal space. Excellent drummers can do this. Our current drummer can do this pretty well, not as well as the university teacher, but pretty good. Your drummer needs to learn how to do this.
A big +1 to this. Drums can be a loud instrument. Still, too many drummers think you have to beat the heck out of them to play rock or metal. A good drummer - especially someone who's played in jazz combos - doesn't have to play loud to sound good.
That being said, the other suggestions are also excellent. Hearing protection, headphone or IEM amplification, brushes instead of sticks, etc. You've probably already suffered an amount of hearing damage. When your ears hurt, something needs to be done about the SPL immediately. There's no point being a musician once you've gone deaf.