Harding, 30, and Sloan, 31, met at Brown University as music students and later played in a band together. They figured others might enjoy hearing them overanalyze the musical components of Top 40 music, and they were right. Their show now receives over 100,000 downloads a month. Fittingly, the first episode to go viral was about Jepsen’s second-biggest hit, “I Really Like You.”

Switched on Pop takes the work of pop stars like Jepsen, Justin Bieber, and Ariana Grande seriously as music. While there is a surfeit of music criticism focused on the lyrics and personal backstories of these artists, there is little that considers the role of certain chord progressions or instrumentation. Harding and Sloan believe that the people behind today’s pop music are often brilliant composers, and that the nuance of their work is too frequently missed.

Quartz’s conversation with Harding and Sloan has been edited and condensed.

Quartz: For the uninitiated, lets start with an example of how the show works. In a recent episode, you analyzed the song “I’m The One” by DJ Khaled, which hit number one on the Billboard charts in May 2017. What did you find interesting about that song?

Sloan: Our goal is always to figure out why a song is resonating with people. Often the reason has to do with some musical technique that people might understand viscerally but not intellectually. In the case of DJ Khaled’s “I’m the One,” we thought the secret was the chord progression. Khaled is using a chord progression, the 1-6-4-5 progression, that has been used in some capacity for centuries. It’s the same progression that undergirds songs like “Blue Moon“, “Stand By Me“, and “I Will Always Love You.” Khaled is using this chord progression that we are all deeply familiar with, and it can’t help but get stuck in our heads.

So for that episode we dive into the world of tonal harmony and how the music theorist Jean-Philippe Rameau first encoded the way that musical harmony can work on our emotions in 1723. Now, three centuries later, whether he knows it or not, DJ Khaled is taking advantage of those same principles.

Switched on Pop is unique in how seriously it takes Top 40 music. What do you make of the criticism that the Top 40 is too frivolous to deserve such close reading?

Harding: I would almost invert the question. Why do we spend so much time paying attention to music listened to by such niche audiences? It’s strange how little we analyze the musical elements of what is mass consumed and central to our society. Writing music that is catchy and simple is extremely challenging. You will often see that the people behind it have gone to conservatories to study composition. Producing a hooky melody requires often a lifetime of practice and a lot of craft.

Sloan: The idea that writing “frivolous” music doesn’t take a lot of artistry is misguided. Mozart’s opera buffa “Così fan tutte” has the most ludicrous and silly plot, but man is it complex. It took all of Mozart’s considerable compositional skill. The music being put out by Justin Bieber and Diplo is completely analogous.

We had a producer duo on our show called Grey, who produced the Hailee Steinfeld song “Starving.” They said they spent 60 hours just fine tuning the sound of the snare drum on one of their songs. That gives you an idea of the immense efforts of a song you digest in three minutes and 30 seconds like an amuse-bouche.

The most frequent criticism of Top 40 music is that it all sounds the same. Do you disagree with that?

Sloan: I don’t think we would dispute that a lot of pop music sounds the same. That is basically true of any genre. A lot of Viennese classical music from the 18th century sounds very similar, and a lot of indie rock sounds very similar. Musical style is defined by stylistic cohesion. I don’t think it should surprise us that Top 40 has some sonic similarities. But I think the pejorative connotation is undeserved.

What we are trying to do on our show is describe how this music sounds the same with a little more nuance. For example, one of the most salient recent trends in pop music is the emergence of the “pop drop.” Instead of a chorus, 99% of the music on the radio now has this super dancey instrumental that is borrowed from EDM [electronic dance music].

Which mainstream pop artists or producers do you think don’t get enough credit for their brilliance?

Sloan: The songwriters Julia Michaels and Justin Tranter come to mind. Most people are not familiar with them, yet these people are quietly responsible for more of the music we listen to than anyone not named Max Martin. They have worked with everyone from Justin Bieber (“Sorry“) to Selena Gomez (“Bad Liar“) and Nick Jonas (“Close“), and have shaped the sound of contemporary pop in a profound way.

Harding: The thing that stands out for me about them is that they are extraordinary melodists. I remember one time the two of us talked for an hour, off-air, about the melody of Julia Michaels’ solo song “Issues,” which Michaels and Tranter wrote together.

It feels like a classic Broadway tune in its arc. It has a question-and-response verse and then a build into a pre-chorus. But then, in the chorus, she inverts the question and the answer in a way that musically and lyrically subverts our expectations. The melody is so clearly, deeply workshopped so that the words and music work together.

Finally, from a music theory perspective, what do you think are the 2017 songs of the summer?

Sloan: Calvin Harris’s current songs on the charts, “Slide” and “Feels“, are our current picks as unparalleled summer jams. Both are andante—a good tempo good for strolling down the street on a summer afternoon. My litmus test for a great song of summer is whether it feels like everything happens in musical time to whatever song you are listening to. The tempos of these songs allow that to happen.

📬 Sign up for the Daily Brief

Our free, fast, and fun briefing on the global economy, delivered every weekday morning.