Sure -- sit on the sub with your speakers off and your headphones on. Should scramble your eggs right well.
Can I use Headphones AND a Subwoofer?
Has anyone done this before. I have the Senn HD650s which, I don't think are considered closed. They're not like the AKG K100s either though. I'm missing the sensual bass I used to have with my speaker system and was wondering if this would be a fruitful pursuit. Any thoughts besides, "Your Crazy!"?