If it's cymbals you're having trouble hearing, you should visit your local audiologist pronto. You might not get your hearing back but you might realize how much you've lost, and you can learn how to prevent it from happening in the future. And in such a case, you might indeed have to boost your EQ permanently, but the tests will show you exactly how much and in what bands so the end result will sound flat to you. Good luck, my friend...and please take this seriously, it's serious.
BTW -- after being in a band where I had to stand near the cymbals --
I got a set of custom-made earplugs (yes, they poured some kinda goop
in my ears to make the mold). They cut down the sound level like crazy,
but, thanks to a special channel, you don't have that pressure buildup
in your head that makes it feel like you have cotton stuffed in, and it
doesn't totally wipe out the high frequencies, just the edginess thereof.
I can hang out right in front of giant speaker cabs and not have any problems
whatever, and nobody can see them so I don't feel like I have a wooden
leg or something (another advantage of being a longhair :-) These things
only cost about $40, but that was in 1993.