Simon was born in London, the son of Alan Emmerson, an architect who had also worked as manager for the rock band Screw, and his wife, Mercia (nee Samson), a sociology lecturer, both members of the Communist party.

He attended Forest School Camps, in which his father was heavily involved, and there he developed his love of folk song, nature and bird watching.

Emmerson began to work as a producer around this time, earning credits on an album by Manu Dibango.

In the same year Emmerson was nominated for a Grammy for his production work on Baaba Maal's album Firin' in Fouta.

Emmerson joined Lush Cosmetics as musical director in 2008, composing soundtracks to some of their spa experiences.