Harmonium is a composition for chorus and orchestra that could be considered a choral symphony in all but name, by the American composer John Adams, written in 1980-1981 for the first season of Davies Symphony Hall in San Francisco, California. The work is based on poetry by John Donne and Emily Dickinson. It is regarded as one of the key compositions of Adams' "minimalist" period. The San Francisco Symphony and the San Francisco Symphony Chorus, with conductor Edo de Waart, gave the premiere of the work on 15 April 1981, and subsequently recorded it. The UK premiere was on 13 October 1987 at Birmingham Town Hall, with the City of Birmingham Symphony Orchestra (CBSO) conducted by Simon Rattle. Rattle and the CBSO gave the London premiere on 28 July 1990 at The Proms.
Each movement is a setting of an entire poem:
- "Negative Love" (by John Donne)
- "Because I could not stop for Death" (by Emily Dickinson)
- "Wild Nights" (by Dickinson)
Timothy Johnson has discussed various aspects of the harmonic language of Harmonium in detail. K. Robert Schwarz has noted the influence of the musical techniques of Steve Reich on Harmonium, and also has commented on the less schematic and more "intuitive" manner of Adams' composition in the work.
Harmonium and The Chairman Dances (another work by Adams) were featured in the Civilization IV soundtrack.