Núñez was born in New York City, and grew up in the Dominican Republic and New York's Washington Heights neighborhood.[2][4] He graduated from New York University in 1988 with a B.S. in piano performance.[1]
Núñez is the recipient of numerous awards in addition to the MacArthur Fellowship, including a 2009 ASCAP Concert Music Award, the 2009 New York Choral Society’s Choral Excellence Award, and the 2005 Liberty Award from the New York Post.[1] He is a member of ASCAP.[5]
Núñez founded an annual festival called Transient Glory in 2001. Transient Glory features original compositions created expressly for YPC by award-winning composers such as Paquito D'Rivera. The Transient Glory festival has been performed at leading New York City music venues such as Carnegie Hall.[6]
Núñez also leads the University Glee Club of New York City, its fifth conductor since the all-men’s choir was established in 1894. He served as the director of choral activities at New York University from 2003 to 2010.[1]
Núñez served as conductor of the 2011 North Carolina Middle School Honors Chorus. Núñez wrote a piece entitled 'Forever Is My Song' for the event.
On May 19, 2014, Núñez was awarded the NYU Steinhardt Distinguished Alumni Award (and received a tie custom designed for NYU by Salvatore Ferragamo).
Núñez is married to Elizabeth McKinney and has two children, Sebastian and Sabrina.