Just to share an answer from Sennheiser service engineer i got about the grills function
QUERY TO SENNHEISER ASIA
Some headphones I have seen have some metallic grille on them, does that
mean that sound can come out of them. Does metallic grille produce better
sound as some headphones claim?
REPLY FROM SENNHEISER SERVICE ENGINEER
Closed headphones and opened headphones have different technologies.
For good quality headphones, there is a material in the headphone is very
good sound absorber.
So there is no reverberation in the space from the speaker to the ear.
A good example is our HD25
For opened headphones, there is less worry of this factor hence it is
cheaper to build.
The metalic grill you mentioned serve this purpose, to let the sound
escape.
The setback is that you sometimes hear the outside atmosphere if you have
very small volume.
The shape of this grill is designed so to reduce this sound to the ear.
What do you think about this?
i got some other few queries answered too, if anyone interested, i can also post them.
