The idea of sadness connects the music of Adele, Kendrick Lamar, Billie Holiday, the English folk singer Nick Drake, the metal band Slayer and Wolfgang Amadeus Mozart.
But no streaming service is going to tell you that. They would seem to prefer that you continue to follow your usual patterns of listening — which they have put effort into recognizing — or, in a mood-based playlist, to stay within easily identified genres and sounds of melancholy.
We now have something close to instant, unlimited, often free access to the history of recorded music. But the recommendation engines of the Internet are teaching us to listen more conservatively, through obvious connections based on our casual choices. How can we learn to really listen across genre and era, in a way that takes full advantage of our astonishing new power, this vast musical inventory? How can we listen better than we are being listened to?