[1][2][3] Mullen was music director on radio and television programs in addition to his work as A&R representative for Rodeo Records for a period of time in the 1960s.
[3] Mullen originated from a musical family and learned how to play the 5-string banjo, fiddle, guitar and mandolin at an early age.
[10] Mullen also played various instruments on numerous entertainers' songs such as Fred Mckenna[11] and the Boutilier Brothers,[12] in addition to production roles for Rodeo Records during this period.
He joined "Don Messer's Jubilee" on CBC television in 1962 and made regular appearances as banjo player performing with the likes of Myrna Lorrie[14] and others until the show's cancellation in 1969.
[3] Starting in 1970, he was music director and band leader of "The Hickorys" consisting on Ron Naugle, Ken Meisner and Stan Taylor[15] on CBC's Countrytime[1][16] filmed in Dartmouth, NS.