Sound proofing the room
Its not possible to elimnate sound completely.

This helps me.
Close the doors and switch on the AC and that creates a type of vaccum and less sound is heard out side the door.
But i have thick glass windows but some other material used for my sliding windows.
Not the normal thin windows.
I too was not able to hear my door bell one day and my grandma was waiting outside the door for 1/2 hour , i then decided no more vaccum & loud noise when i am alone at home.

Also How much is Loud according to u.
Do you want so break some glass[def of loudness]

And i feel sound must allowed to flow instead of trapping it inside ur house.