"Classical Gas" is an instrumental musical piece composed and originally performed by Mason Williams. Originally released in 1968 on the album The Mason Williams Phonograph Record, it has been re-recorded and re-released numerous times since by Williams. One later version served as the title track of a 1987 album by Williams and the band Mannheim Steamroller.
Williams was the head writer for The Smothers Brothers Comedy Hour at the time of the piece's release and premiered the composition on the show. Williams performed it several times over several episodes. After the piece had reached the Top Ten, Williams asked an experimental filmmaker named Dan McLaughlin to create a video montage of classical art works edited in time to the music, using the visual effect now known as kinestasis. The pioneering work, 3000 Years of Art, premiered in 1968 and may have helped push the song high on the charts; it peaked at Number 2 for two weeks in August that year.
Williams re-recorded "Classical Gas" as a solo guitar piece on his 1970 album Handmade. This version was re-released by Sony in 2003, after being featured in the film Cheaper by the Dozen (which starred Williams' Smother Brothers protégé, ).
During the 1970s and early 1980s, many television stations (such as WTAE-TV in Pittsburgh, WBAL-TV in Baltimore, KNTV in San Jose, and WNEP-TV in Wilkes-Barre, Pennsylvania) used the composition - or a version of it re-recorded by Telesound - as their theme song.
There is a common misconception that "Classical Gas" was composed and performed by Eric Clapton. Clapton has never recorded a cover of the song. This misconception may possibly be attributed to the fact that Clapton was musical director of, and played much of the guitar music for, the feature film The Story of Us. The version of the song on the film's soundtrack is actually Williams's own solo-guitar re-recording of it, from his 1970 album Handmade.