How we hear sounds. 22. 7. 2014 When we hear sounds this what actually happens. Firstly the sound waves enter the canal of the ear that makes the eardrum vibrate. Next the vibrations pass through three connected bones in the middle of the ear. Then this motion sets fluid moving in the inner ear. After that the moving fluid bends thousands of delicate hair like cells which convert the vibrations into the nerve impulses. Finally it goes in the brain, these impulses are converted into what we hear as sound.