The three knocks seam to be a distraction either from a spirit or your subconscious mind. You may have something on your mind at that moment or you maybe dreaming of something that that is not good for you. A spirit or your subconscious mind seams to be telling you, Don't Think Of This! or Wake- Up! Next time you hear the three knocks try to think of what was on your mind or what were you dreaming of at that moment?, whatever it is it does not want you to think or dream of this. From my own experiences it seams to be connected to adultery and divorce.
sound door
Here, hear, and hare are three homophones for hear.
hear
It is possible to hear a teacher through a closed classroom door if the teacher is speaking loudly or if the door is not soundproof. The ability to hear through a closed door also depends on the thickness and material of the door.
I Still Hear Your Voice at Night was created on 2011-01-29.
1) Pet 2) Fridge 3) Creaky window/door 4) Other people
nocturnal
Did you hear about the girl and the guy who met in a revolving door and started going around together is the answer.
It's Shambala by Three Dog Night from 1973. Michelob beer is also using it in their TV ads. You can hear the song here: http://www.last.fm/music/Three+Dog+Night/_/Shambala
I hear- The secrets that you keep- - When you're talking in your sleep-
Mama thinks all three of her children saw the night men in Chapter 4 of "Roll of Thunder, Hear My Cry."