Ryan Owen Granville Williams, better known by his stage name Roni Size, is an English DJ and music producer. He came to prominence in 1997 as the founder and frontman of Roni Size & Reprazent, a drum and bass collective. That year they won the Mercury Prize for their debut studio album New Forms.

Roni Size & Reprazent are a British drum and bass group fronted by Roni Size. Their debut album New Forms won the Mercury Music Prize in 1997. Their follow-up album In the Mode featured artists including Rahzel, Zack de la Rocha of Rage Against the Machine and Method Man.