'Voice' contestant Devon Barley is already participating in his second NBC vocal competition after appearing on the a cappella contest 'The Sing Off.' The pre-med student at the University of Vermont earned a spot on Adam Levine's team with his performance of Jason Mraz' 'I'm Yours.'

Despite his demanding curriculum, Barley says he tries to find a good balance between his studies and his singing aspirations. "With me, school is always a big priority but so is singing," the 20-year-old from Massachusetts tells SouthCoastToday.com. "To focus just on school is not possible. To not be involved with music, that's never an option."

Barley and his a cappella group the Top Cats made it through the first round of cuts on 'The Sing-Off,' and it was that experience that helped lead to his appearance on 'The Voice.' "The same casting people were working on 'The Voice' and they invited me to come and audition," reveals Barley.

Barley admits he was nervous before performing in front of the four 'Voice' coaches. "Having to sing in front of America is one thing, but in front of a panel of artists you've grown up listening to was the single, most intense moment of my life!," wrote Barley on a post-show blog. "I get pretty bad stage fright right before I go on in any performance but this was by far the worst."

Nonetheless, Barley's performance of 'I'm Yours' won the approval of Levine and Cee Lo Green, and the young singer ultimately chose Levine to be his coach.

Watch Devon Barley and the Top Cats Perform Gavin DeGraw's 'In Love With a Girl'

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