an Article on the subject from THe Dallas Morning News
There is a nice little article on the subject in The Dallas Morning Times.
(see Attached)
My personal experience is that I listen at lower volumes with my Ultrasone HFI 580 phones without feeling the need to Crank 'Em Up. On top of that, they are just fabulous headphones! Your mileage may vary, but I haven't met anyone who has actually tried the Ultrasone cans and not been impressed. There is no electronic hocus pocus, they just position the drivers to utilize your outer ear instead of "beaming" the sound straight into your ear canal. I wouldn't be surprized to see larger companies start doing this. They will probably even create "Research Papers" to take credit for it!
I found out about these from a friend who bought an inexpensive (not cheap though, I think around $95.00) Ultrasone set that I believe is called Zino (or maybe Zinio?) and they are superb for earbud relacement to use with iPods, etc. They are way nicer sounding than any buds I have tried, don't put a "plug" in your ears, and are very light.