Quote about the balls in the house.

The people!! I also thought of the neighbors before, but you raised the topic and I became curious. So here! I talked to 3!! Candidates of Sciences in Physics. Opinions agreed that the sound insulation there is silly, especially for low frequencies. The sound is heard by everyone. And the sound itself is caused by some processes in the elevator mechanism, but these processes occur rarely, so this is not the movement of the elevator, but most likely its checking with lifts (standard bypass). These are things.

Thank you to Archangel Julia Serafimovna for the detailed explanation of this thought.

ZZY put the quote plus, because this is the only version so far and see it should as many people as possible)