John Sadak joined the Greenville Symphony in 2011 as Second/Bass Clarinet and was named Principal Clarinet in 2023. John also performs with the Charlotte Symphony, Opera Carolina, and the South Carolina Philharmonic. During the summer, he is a Festival Artist at the Wintergreen Music Festival in the Blue Ridge Mountains.

A native of upstate New York, John earned his MM in Clarinet Performance from the Manhattan School of Music. After graduation, he was Principal Clarinet for the Miami City Ballet. Two years later, he was appointed Bass Clarinetist for the Florida Philharmonic Orchestra and Florida Grand Opera. He has collaborated with musicians ranging from Itzhak Perlman, Cecilia Bartoli, and Andre Bocelli to Ray Charles, Buddy Rich, and Marvin Hamlisch. John has also been active as a studio musician in New York and Miami, recording for various commercial artists, and has recorded for the Naxos and Albany Records labels.

Previous faculty positions include Wake Forest University, Davidson College, Florida International University, and the New World School of the Arts in Miami. John has given Master Classes in New York and Miami as well as the South Carolina Governor's School of the Arts and Humanities, and also has an active private studio of clarinet students in Charlotte, North Carolina.