Summary: Perhaps it was just these headphones or perhaps it happens in all closed supraaural phones, but these cans provided an incredibly poor seal and isolation. When I wore them, I kept hearing this high-pitched noise like the sound of air being passed through a very small crack in your window. The only way I could achieve some good sound is if I actually pressed the two sides to my head with my hands. I think that alone speaks volumes on the quality of these cans.
Summary: While I don't own these anymore and they may not be as fresh in my mind as they should I know I liked these headphones. Despite being slightly uncomfortable and not something I would wear for an extended period they had a great clean and clear sound and I don't remember any problems with to much sound getting in, or to much music getting out in public.