I had some momentums that I never opened (flipped them to fund my HD600 purchase). I considered trying them out, but was unsure due to the published frequency range, which falls well short of even the HD598. I also personally am not interested in a closed headphone, as I often need to hear the baby monitor while I'm watching a movie. Bass is clearly a need for movies. You mentioned needing more detail, too. I'm soon going to try the Beyerdynamic 990, which I've read has both of these features. I've also read warnings about it's overly bright treble; I wonder how that will sound on a sequence like the lobby scene in the Matrix. Can't wait to try!