Pop music surrounds us, but how often do we really listen to what we’re hearing? Switched on Pop is the podcast that pulls back the curtain on pop music. Each episode, join musicologist Nate Sloan and songwriter Charlie Harding as they reveal the secret formulas that make pop songs so infectious. By figuring out how pop hits work their magic, you’ll fall in love with songs you didn’t even know you liked.

The sound of R&B is difficult to pin down.

Since the 1950s, the label has been used both as a genre and as a catch-all for the entirety of black popular music. Soul, funk, disco and even hip-hop have at times been covered by this R&B umbrella — Billboard has changed how it counts what genres over the years.

On Chance The Rapper's new album, "The Big Day", all of these influences come through. He's not alone. On Kehlani's recent records for example, 90s R&B and 2000s trap both play a role. But both these artists are a far cry from the 50s R&B sounds of Sam Cooke.

To understand how R&B has changed over time, we consult with Trevor Anderson, manager of Billboard's R&B/Hip Hop chart. Then we speak with R&B super-producer Oak Felder to understand how R&B is progressing and what it might become.

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