Ok, so I'm brain-dead when it comes to cabs, so I beg for a little help. Let's say that I have a 200w head at 4ohms. What will happen if I run it through a cab rated at 8ohms. I really don't understand how the whole ohms thing works, and although I've seen a few threads that sort of explained it, I didn't get it. Answers would be appreciated, in extreme lamens terms.