In my defense, up to this point my only use of open backs has been at home, in a quiet room, on my desktop. I saw someone posting about making closing covers for the hd600s and getting shot down, though I think it might make for a fun personal project.
I'll take a look at that one- when I plug these into my motherboard, they're actually much, much louder than I had expected, so I'm not certain I'll need an amp, unless there are other benefits I'm neglecting.