Thanks. It was just astonishing that the vibrations transmitted upwards. I guess that means it was transmitted first to your floor, then to the walls, then to your ceiling (ie, your upstairs neighbor's floor). It was amazing that after all that traversal, there was still enough energy left for the upstairs neighbor to perceive it (whether he was disturbed by it or not).
I just felt surprised because, in my experience of apartment living (whether wood frame or concrete), I was most of the times disturbed by the footsteps from upstairs, but never from downstairs. I guess your old apartment did have a terrible structure.
