There must be a word or phrase for this in some language.

The bus is packed today. No empty seats, people huddled together standing in the aisles. But no one is talking, not even friends sitting close to each other. All that is heard is the hum from the electric motors. The silence from inside the cabin can not be characterized as awkward, but more akin to the sound of water running down a steep cliff. The silence calms, an inverse relation to day the, most people here have suffered through. Collectively people must work together to reach this point of serenity. Without a word, a force higher than comprehension, subconsciously guides us to a place that emanates the sound of nothing.

Then suddenly, the flick of a telephone.
A young woman asks her mother about dinner in korean, the whole bus hears hear words.