His signature voice is an impersonation of Orson Welles. LaMarrche as well provided a voice of A alive character The Braaround in Little finger & a Brain, world health organization is modeled fallowing Welles; numbers of Little finger & a Brain episodes come nods to Welles's career. "The Third Mouse" is according to The Third Man and inside another episode the Brain stages the faithlessly alien invasion for television, in the studied attempt to achieve what Welles's radio adaptation of The War of the Worlds accomplished by accident.

LaMarche has voiced Welles himself from time to time. He dubbed on top a voice of Vincent D'Onofrio's performance of Welles in the film Ed Wood and parodied Welles again in The Critic, in which a video will devolves into a commercial for Rosebud Frozen Peas. Inside Codename: Kids Next Door he is the voice of Father (Mr. Wigglestewithin) & in Jukebox's Catscratch he is the voice of the butler, Hovis.

LaMarche has besides portrayed: Chief Quimby around Inspector Gadget Egon Spengler in the many incarnations of the Ghostbusters cartoons Numerous secondary characters around Futurama including Kif Kroker, Morbo, and Brainspawn Alec Baldwin for the 2004 feature film, Team America: World Police. Kellogg's Froot Loops mascot Toucan Sam Xiaolin Showdown - Master Fung (Seasons 2-Three) & numbers of others

LaMarche joined a cast of The Transformers television series after a release of Transformers: The Movie. Oddly, LaMarche did non voice Unicron, a character whose voice was provided by Welles in the film.