Och du funderar på enbart slutna (DT770) eller kan även tänka dig öppna hörlurar?
http://en.wikipedia.org/wiki/Headphones#Open_or_closed_back
Open or closed back
Both circumaural and supra-aural headphones can be further differentiated by the type of earcups:
Open-back headphones have the back of the earcups open. This leaks more sound out of the headphone and also lets more ambient sounds into the headphone, but gives a more natural or speaker-like sound and more spacious "soundstage" - the perception of distance from the source.
Closed-back (or sealed) styles have the back of the earcups closed. They usually block some of the ambient noise, but have a smaller soundstage, giving the wearer a perception that the sound is coming from within their head. Closed-back headphones tend to be able to produce stronger low frequencies than open-back headphones.
Semi-open headphones, have a design that can be considered as a compromise between Open-back headphones and Closed-back headphones. This may imply that the result combines all the positive properties of both designs. Some believe the term "Semi-open" is purely there for marketing purposes. While there is no exact definition for the term semi-open headphone, there are designs that can be considered as such. Where the open-back approach has hardly any measure to block sound at the outer side of the diaphragm, and the closed-back approach, really has a closed chamber at the outer side of the diaphragm, a semi-open headphone can have a chamber to block sound partially while leaving some sound through, via openings or vents.