William Paul Mitchell (born March 21, 1972) was born in the Harlem section of New York, New York. He moved, in his early childhood, to Flushing Queens were he was raised. He is best known as Large Professor, also as Large Pro and Xtra P, and is a New York based hip hop record producer and emcee. He is also best known as a member of the influential underground hip hop group Main Source, and for discovering popular emcee Nas.