It’s simple. With closed headphones, the housing is designed in such a way that little or no ambient noise can be heard. In addition, hardly any noise from the headphones reaches the outside. Because of this, care is taken in the development of closed headphones to use sound-absorbing materials.
With an open headset, on the other hand, you can perceive the sound more naturally and get a better sense of spatiality. The design of open headphones is responsible for this. This is characterized by sound-permeable materials or openings, such as those of the MMX 330 PRO.