Not sure if this is question for this part of SE.
Anyway, how would you sound proof a door that is made just with wood frame and a sheet of glass 5 milimeters thick? I got to some ideas like Egg crates but that is too tall to fit properly in the space available. I could cut it but it would look ugly.
Another idea I got is bottle caps, but that way I have to buy lot of bottles to cover the whole area.
Here are some images I made of my door. The glass is covered with wood-lookalike duck-tape.
As you can see from the second image the frame has space which is 2-2.5 centimeters deep.The Egg crate is about 6 centimeters tall.
Any ideas are welcome.
I got inspiration by NASA soundless room: