Even though it may sound (no pun intended) "uncool", but you should really use ear plugs in loud concerts. I recommend not the ones made of wax (ewww), but polyurethane foam as the material of choice. They fill most of the outer ear canal, and filter loud noise, while letting you still hear your neighbor's voice (-:

You will need your ears, when the revolution comes. (-;

Definitely. I wish I had remembered to buy some before I went.

Yeah, not a joke. I have some high-end hearing loss, apparently due to a combination of bad internal design and "exposure" (read: playing in bands when younger). This is not a big deal, as long as you don't mind cogently answering "What?" to any question that has a sibilant in it. Remember the rule of thumb: eyes recover, ears don't.