https://newatlas.com/technology/sound-bubble-headphones-tune-out-background-noise/
The campus was busy. From his office window he watched the students below. The quad was as crowded as it had been for generations probably. Others were walking in small groups between lectures. He remembered when he first started, watching the brightest and best minds arguing with each other over literature, philosophy or politics. He’d been here long enough to remember raised voices and the sound of the occasional fight floating through his window. They were still talking but agreement didn’t make as much noise it seemed. On the grass each group’s bubble was set to filter out opposing views.