[Uncle Erik]

I don't listen to rap/hip-hop, so I can't give advice there, but a couple of headphones come to mind that you might enjoy.

One is the Beyerdynamic DT880. It has a huge amount of clarity and detail and is slightly forward in the high end. You will hear the shimmer of cymbals and the crackle of snares just fine. The bass is there but not overpowering and is clean. A lot of people love this headphone - myself included - and it does great with R&B, pop and rock. It goes for about $300 these days, though you can find used ones for less.

Another is the Sony MDR-SA5000. It is one of the most detailed headphones I've ever heard - you won't miss a thing with them. The highs are crisp and the bass is pretty good, too. However, these are polarizing and people either love them or hate them. Also, the wires can get flaky and sometimes need repair. I had to resolder the leads on the left earpiece for mine. They've been fine since, but keep in mind that this happens to quite a few owners. I'd recommend a lot of searches and reading before you buy a pair, but they might be exactly what you're looking for. B&H sells them for $370, which is a little above your budget.