With a youthful smile and infectious optimism, bassist and vocalist Esperanza Spalding is boldly challenging how mainstream audiences define “popular” music.

Spalding has already had an impressive career. At just 27 years old, she’s the youngest faculty member at the prestigious Berklee College of Music in Boston. Her most recent album, “Radio Music Society”, peaked at no. 10 on the Billboard 200 chart and was the no. one album on the Top Jazz Albums chart. Perhaps most famously, she won the Best New Artist Grammy in 2011, defeating Justin Bieber, Drake, Mumford & Sons and Florence + the Machine.

Yet, despite all of the attention she has received, she remains humble and eager to share the spotlight with other musicians who wouldn’t ordinarily be noticed by mainstream audiences, including saxophonist Joe Lovano and drummer Jack DeJohnette, who are very well known in the jazz community.

“One thing that irks me a little bit is this idea that people paying attention to you is good for everybody,” Spalding said in an interview with the New York Times. “But it’s such a focused beam of light that that’s not realistic. Unless you intentionally go, like, ‘I’m with him!’ ” Referring to her album “Radio Music Society”, she explained that “the idea of this society is: yeah, we are making this music. And it really takes a ‘we’ to make this kind of music.”

This atmosphere of sharing and collaboration is one of the defining characteristics of her music. Her recordings borrow elements from many different musical genres, such as jazz, classical, pop and fusion. But the genres meld together so seamlessly that her music transcends traditional genre stereotypes and becomes something else entirely — something completely new and original.

In some ways, listening to Spalding’s music is like eating at a buffet. Some food has a familiar and pleasant taste, while other food has a new and unfamiliar taste but is still delicious. The familiar and unfamiliar food might even be mixed together to create a new dish, which has a very distinctive, satisfying flavor.

For example, “Radio Music Society” contains enough pop elements to satisfy the existing tastes of mainstream audiences without making the music formulaic or unoriginal. At the same time, Spalding pours the perfect amount of jazz into the mix. An occasional trumpet squeal, big band riff, intricate piano solo or lively bass line from Spalding herself is enough to satisfy fans of “real jazz” without overwhelming listeners that may be hearing elements of modern jazz for the first time.

Spalding believes that the radio is an extremely valuable tool to expose listeners to new kinds of music.

"The benefit of the radio is, something beyond your realm of knowledge can surprise you, can enter your realm of knowledge," Spalding explained to NPR host Rachel Martin. "Part of the premise of that stems from my concern about the accessibility of jazz, just how people can access it. If you don't already know about jazz music, how would you be exposed? How would get an opportunity to find out if it spoke to you? If you get exposed to it enough, you might find a taste for it."

This is the magic of Spalding’s music. Her recordings contain a little bit of everything, yet it’s virtually impossible to pinpoint any one genre at any given moment. It’s a futile effort to try to define her recordings using traditional musical labels. Spalding simply makes music — thoughtful, deliberate, spirited music.

Perhaps the most intriguing parts of Spalding’s compositions and arrangements are the quiet moments: some sustained bass notes, the light touch of a drum stick on a cymbal, the whispers of an organ. These moments give the music some breathing room.