What is the difference between an (open interval) and a [closed interval]?

What is the difference between closed and open headphones?

• I've seen a lot of headphones that are open or closed, but I never really knew what the difference is. And which one should I get if I dont want to bother other people around me with my music? When we finish a test at school we are allowed to listen to music until the rest is done, so it would be really bad if the others heard my music too, or doesnt it matter with open or closed headphones? and also, i want to block out as many sounds from the outside as possible when listening, although, i often listen to music when im going to school, so it should at least minimize the sounds from the outside coming through but still be (kinda) safe to wear when on the bike. And if you have any suggestions, please post a link ^^

• Answer:

  Per wikipedia: The housing, or earcup, of an earcup headphone will be either open or closed. Open headphones, sometimes marketed as “open air” headphones, have an open grille on the back of the earcup, exposing the driver to the outside and allowing sound waves to propagate away from the ear freely. This backing type does not isolate the listener from outside sounds Closed headphones have a sealed backing, which attenuates sound waves propagating away from the ear. As a result, listeners away from the headphones cannot hear the produced sound easily. In addition, sound from outside is attenuated by the sealed backing, providing a level of isolation to the listener. A sealed chamber is often claimed to have the negative effect of distorting sound in certain frequencies due to resonances within the earcup housing, however, bass frequencies are stronger in a sealed chamber headphone design.