I'm mostly new to the headphone game, and I'm looking to buy some nice headphones ($370 max) and I was wondering what would be the best headphones compared to the preferences I have:

Closed back
Around the ear
Good for gaming yet I can still listen to high quality opera and jazz

If they are cheap enough I might consider buying an amp if they need it. As I stated il new to this, but I'm eager to learn. So if someone wouldn't mind telling me about how impedance effects headphones, that'd be great. I know what resistance/ohms law is I'm just not sure how it relates to headphones.

Thanks in advance!