I believe that comfort plays hugely in the role of how you view what you hear.
Most modern planar magnetics are weighty/heavy/impractical to wear, they bear strain on your head and I feel that contributes to a closed-in sound and perhaps even a more 'weighty' sound.
Open dynamics are much more comfortable to wear and generally create a more expansive wider stage, similar with electrostatics.
HD800 being a popular dynamic headphone is almost weightless, 'disappears in your head'-level of comfort. They are considered to be the most open sounding out at the moment.
Anyone concur with me?
Edited by nehcrow - 7/7/14 at 5:34am