Main Source is an innovative, acclaimed Toronto and New York-based hip hop group comprised of Toronto natives Sir Scratch, K-Cut, and New York native Large Professor. Their first album, Breaking Atoms, featured conscious MC tracks such as "Looking at the Front Door", "A Friendly Game of Baseball" and "Watch Roger Do His Thing". The album also has the first on-record appearance of Nas on "Live at the Barbeque", which also featured Joe Fatal and Akinyele.