Need some new sealed headphones and am looking for good isolation and a flat response. Budget is not a major concern but I'm not planning on spending more than $1000, and the less I spend, the more I have to spend on other gear - I need to get a new amp as well.
From looking at measurements and reviews online, it seems like the MDR-7520 (which are supposed to be the same as the Z1000) or the Sennheiser HD280 Pro are the best headphones for isolation and a flatter frequency response required for studio work.
Isolation and accuracy are important, so please don't recommend Denons or anything that is closed but doesn't isolate, or are tuned to sound pleasing instead of accurate.
Durability is important as well, and it looks like the Sony 7520 is one of the sturdiest headphones around with its magnesium construction. An easily replaceable cord is very useful to have as well, and it looks like the 7520 just uses a 3.5mm jack, though you would need one of their cables if you want it to lock in place.