Mark Howes Metcalf is an American actor. He was born March 11, 1946, in Findlay, OH. He portrayed Bob Cobb AKA The Maestro on Seinfeld. He is best known for his role as Neidermayer in National Lampoon’s Animal House. Mark also appeared in two music videos for Twisted Sister: “We’re Not Gonna Take It” and “I Wanna Rock”.