Join Joshua Duchan on Thursday, Sept. 14, for the next Knowledge on Tap event at HopCat Detroit as he discusses ethnomusicology, popular music and his recently published book about the music of singer-songwriter Billy Joel.

When Joshua Duchan decided three years ago to write a book about Billy Joel, he hoped to score a brief phone interview with the Piano Man.

Never in Duchan’s wildest dreams did he expect to have lunch in the singer-songwriter’s home near Oyster Bay, New York. Yet, there he was, enjoying a Caesar salad and receiving a lesson from Joel on the correct way to eat oysters.

“When I started the project, I told myself that I would try and get in touch with him. I did not expect to succeed,” says Duchan, 37, associate professor of music history at Wayne State University and interim graduate officer for music. “I planned it as such that I could write the book without him. It wasn’t absolutely necessary for me to do what the book set out to do.”

Duchan’s book, “Billy Joel: America's Piano Man,” available now, looks at the singer’s career and music. It explores the unique ways Joel channels and transforms the cultural life of a changing America over four decades into bestselling song after song and album after album.

Duchan spent four hours at Joel’s home in late 2015, much of that time with the singer-songwriter behind the piano.

“We sat there and he played for me. We talked through a lot of his music,” Duchan says. “It was a really wonderful meeting and he was super nice. He was eager to talk about everything. He even remarked to me, at one point, that he’s at the point in his life and career where he is ready to talk about his songs, what they mean and why they were written when they were written.”

The book delves into Joel’s endeavors as a musician, lyricist and commentator on questions of geography and regionalism, politics, working- and middle-class culture, human relationships, and the history of music itself. Duchan draws on key songs from Joel’s career to explore each theme, from his folk-like lament for Long Island’s changing industry and lifestyle in “The Downeaster ‘Alexa’” to his emotional ode to Vietnam veterans in “Goodnight Saigon.”

“This is not a Billy Joel biography,” Duchan is quick to point out. “What I set out to do in the book is to discuss groups of his songs that speak to particular themes.”

For example, there is a chapter about places. In it, Duchan discusses tunes such as “Los Angelenos” and the relation to Los Angeles, “New York State of Mind” and the Big Apple, and several songs about suburbia.

On the back cover of the book, Joel gives Duchan's work his blessing and a ringing endorsement: “This is the most comprehensive and accurate analysis of my work that I have ever read. Joshua S. Duchan has done a brilliant job explaining the many intricacies involved in the construction of the music I have composed and [providing] an insightful interpretation of my lyrics as well.”

Before joining Wayne State’s faculty in 2011, Duchan taught at Kalamazoo College and Bowling Green State University. He earned his Ph.D. in ethnomusicology — the study of music in its cultural context — from the University of Michigan with a dissertation on collegiate a cappella groups.

At WSU, Duchan teaches undergraduate and graduate courses in music history, world music, popular music and ethnomusicology. Outside of teaching, he remains an active participant in the regional and national a cappella scene as an adjudicator, arranger, clinician and producer. One of the things Duchan says he loves the most about teaching at Wayne State is the diversity of the students.

“I remember teaching a class and playing a particular piece of music from Africa,” he says. “One of the students raised her hand and said, ‘My grandmother used to sing me that song.’ You’re not going to find that at many other places. I really appreciate that that diversity doesn’t just enrich my class, but probably enriches every class at the university. That was amazing to me and is one of the many reasons I truly enjoy teaching at Wayne State.”

Being an ethnomusicologist also helped Duchan take a different approach to Joel’s work. Whereas other writers, biographers and journalists were more concerned with the ups and downs of the singer’s personal life, he focused solely on Joel’s music.

As for Duchan’s next book? “Tentatively,” he says, “I’m thinking of James Taylor.”