NASHVILLE, Tenn. – Beck Hansen wants you to think about the way music has changed over the last century and what that means about how human beings engage each other these days.

Laboring over the intricate and ornate details of his new “Song Reader” sheet music project, he was struck by how social music used to be – something we’ve lost in the age of ear buds.

“You watch an old film and see how people would dance together in the ’20s, ’30s and ’40s. You’d go out and people would switch partners and it was a way of social interaction,” Hansen said. “It’s something that was part of what brought people together. Playing music in the home is another aspect of that that’s been lost. Again, I’m not on a campaign to get people to take up songs and play music in their home or anything. But it is interesting to me, the loss of that, what it means.”

Beck hopes the “Song Reader” inspires some of us to pick up instruments and limber our vocal cords. It includes 20 songs annotated on sheet music that’s been decorated in the style popular in the early 20th century when the songwriting industry was a thriving enterprise with billions of songs sold.

The 42-year-old singer notes in the book’s preface that Bing Crosby’s “Sweet Leilani” sold an estimated 54 million copies in 1937, meaning about 40 percent or more of the U.S. population was engaged in learning how to play that song. They were touching it directly, speeding it up, slowing it down, changing the lyrics and creating something new.

“There’s popular bands now that people know the words to their songs and can sing along, but there’s something about playing a song for yourself or for your friends and family that allows you to inhabit the song and by some sort of osmosis it becomes part of who you are in a way,” he said. “So when I think of my great-grandparents’ generations, music defined their lives in a different way than it does now.”

Beck proposed the idea to McSweeney’s Dave Eggers in 2004 and it soon blossomed into something more ambitious as the artist wrapped his mind around the challenge of not just writing a song, but presenting it in a classic way that also engages fans who might not be able to read music or play their own instruments.

They quickly agreed it would make no money, but it seemed like an idea worth exploring.

“And it seemed like only Beck would have thought of it,” Eggers said in an email to the Associated Press. “It’s a very generous project, in that he wrote a bunch of songs and just gives them to the world to interpret. That’s a very expansive kind of generosity and inclusiveness that we’re happy to be part of. On a formal level, we love projects like this, that are unprecedented, and that result in a beautiful object full of great art and great writing. And it all started with Beck. It’s a testament to his groundbreaking approach to everything he does.”

Beck hopes fans will record their own versions and upload them to the Internet so those songs grow into something more universal.

As for his own recorded music, that’s a little more complicated.

Beck’s not sure where he’s headed at the moment. He recorded an album in 2008, but set it aside to work with Charlotte Gainsbourg on “IRM,” which he wrote and produced. He’s also been writing songs for soundtracks and special projects and producing artists like Thurston Moore, Stephen Malkmus and Dwight Yoakam. All that has left him feeling creatively satisfied, but he does acknowledge it’s been a while since he released 2008’s Danger Mouse-produced “Modern Guilt.”

“Song Reader” spurred Beck to think about his own work in a new light. Spending six months finishing off the project after working on it sporadically over the years, he was struck by how much craft went into the creation of each song and how quickly music can come into existence today.

“There is so much music out there, to me,” he said. “I don’t know if it’s just where I am in my own music making or if it’s a product of the amount of music out there, but I feel like a piece of music does have to have a certain validity to be put out there and to ask people to listen. … I feel like it’s impossible for everyone to keep up, you know, so I guess I’ve been feeling like maybe there’s something to picking what you’re going to put out, about being more particular about what you put out.”