Although Melvin Jerome Blanc is remembered today for his voice characterizations for
Warner Brothers, he arguably was the man of 1000 voices not for the
cartoons, but for his work on
radio.
Although he started as a musician (An talented violinist, bassist and sousaphone player, Blanc played in the NBC Radio Orchestra and conducted the pit orchestra at the Orpheum Theatre in Portland), a local radio show he hosted with his wife lacked the funds to hire a cast of actors, so he filled in. Soon Blanc began to appear on network radio in 1934 with a regular appearance on The Joe Penner Show as a duck. You can also hear him on various episodes of The Abbot and Costello Show, The Adventures of Ellery Queen, The Al Jolson Show, Al Pearce and his Gang, Baby Snooks, Baker's Broadcast, The Bob Hope Show, Blondie, The Camel Comedy Caravan, The Chesterfield Supper Club, Fibber McGee and Molly, G.I. Journal, Icebox Follies, Meet Mr. McNulty, Nitwit Court, Point Sublime, and The Tommy Riggs & Betty Lou Show. His character work on these radio shows got him his audition and contract with Warner Brothers. The success of these sent him back to radio, where he leveraged his success into featured parts on the top network shows: He played the Happy Postman on Burns and Allen, Professor LeBlanc on The Jack Benny Program (as well as various animals and Jack's car); Mexican handyman Pedro on The Judy Canova Show (also Roscoe P. Wortle); Pancho on The Cisco Kid opposite Jack Mather; and Floyd Munson the Barber on The Great Gildersleeve. He had his own show on CBS in 1946, The Mel Blanc Fix-It Shop (which, considering his talent, is surprisingly unfunny).
Of all the characters he did, only one of his voices was not original.
Sources: Anthony Tollin, Program Notes to Old Time Radio's Greatest Shows. Radio Spirits, 1997.
Mel Blanc Voiceography, Voicechasers,
http://www.voicechasers.org/Actors/M_Blanc.html
Los Angeles Times Obituary, July 11, 1989.