The 840's are sold as studio phones. I have them and got them for a deal at $129 shipped. Don't think they go for that anymore. They are BIG and closed but the sound isolation even beats my IEMs (in ear monitors). I can't even here people next to me when the music is off. Great sound, solid bass and mids, wide soundstage.

I can't recall who, Wid maybe, recommended Grados to get the closest to Axiom's sound. That was a good call. I've used the 325i's and HF2's, both of which are great phones but open so it's not quiet to those near you. I've heard good things about the Alessandro's as well.

You might check out head-fi.org for suggestions. But make sure to keep the comments in perspective. It can tun into AVS forums once in a while over there.