See two people on the bus, greeting each other after having not seen each other for some time. Conversation lasts no more than five minutes. Then the earphones in and both stare away.
See two friends on the bus, side by side. Earphones in, with no conversation whatsoever, until time to get off the bus and earphones out.
Used to see couples sharing earphones and talking, while enjoying the same music. Don’t see that as much.
With the introduction of the Sony Walkman as of 1979 and into the early 1980s, remember how odd the ads looked, with player hung from neck or clipped to pocket, and earphones. Why would someone want to cut out the world like that?
Where, as of 2016 “Sony’s new noise-cancelling headphones block out the world” and someone “was very impressed by their performance. They dutifully shut out all conversations in the room, even when I wasn’t listening to music.”
So when does music envelop, from a distance, and when does someone re-enter the world…