Clausen has scored or orchestrated music for more than 30 films and television shows, including Moonlighting, The Naked Gun, ALF and Ferris Bueller's Day Off.
[3] He began playing the French horn in the seventh grade and also learned piano; and he sang in his high school choir.
[4] He studied mechanical engineering at North Dakota State University although, after being inspired by his pianist cousin, switched his major to musical theory.
[5] Whilst there, Clausen took a correspondence course at Boston's Berklee College of Music in jazz and big band writing.
[6] He went on to attend the University of Wisconsin–Madison to complete his master's degree, but he quit as he disliked the place, especially what he felt was an "anti-jazz" attitude.
[4][7] Clausen was the first French horn player to ever attend the college and took part in many ensembles; he is also featured on some Jazz in the Classroom albums.
[5] Clausen moved to Los Angeles, California in 1967 in search of television work, wanting to become a full-time composer.
[7][11] Other television compositions included Wizards and Warriors (1983), Fame (1984), Lime Street (1985),[5] Christine Cromwell (1989) and My Life and Times (1991) as well as the television films Murder in Three Acts (1986), Double Agent (1987), Police Story: The Watch Commander (1988), My First Love (1988), She Knows Too Much (1989) and the feature film Number One with a Bullet (1987).
[1] He also conducted the orchestras and, for some, provided additional music for several films including The Beastmaster (1982), Airplane II: The Sequel (1982), Splash (1984), Weird Science (1985), Ferris Bueller's Day Off (1986), Dragnet (1987) and The Naked Gun (1988).
[1] The show provides him the opportunity to score realistic drama, overblown comedy, gritty urban jazz, Broadway-worthy show tunes, and some of the most clever and loving parodies of cheap-o television news themes, '70s action music, and feature film scores ever done.
He has proved beyond a doubt that television scoring is not the vast wasteland it is often purported to be and that an intelligent composer can take even the most demanding shows and elevate them to new heights.—Doug Adams of Film Score Monthly about Clausen's work on The SimpsonsFollowing ALF's conclusion, Clausen was unemployed for seven months.
However, the show's creator Matt Groening told him "we don't look upon this as being a cartoon but a drama where the characters are drawn, and we would like it scored that way."
[5] The limited timeframe proved the most challenging aspect of the job for Clausen; he was once required to write 57 musical cues in one week.
[1] He recorded the album Swing Can Really Hang You Up The Most in 2003, comprising the arrangements he made over his career, performed by his jazz orchestra, after self-financing it.
ASCAP President Paul Williams said his "decades of scores for The Simpsons and other TV programs and films are as endlessly inventive as the imaginations of the shows' writers and animators.
"[16][23] On August 30, 2017, after 27 years of scoring for The Simpsons, it was revealed that Clausen was dismissed from the show, with suggestions that the reasons behind the decision were largely financial.