Lead vocalist and guitarist Serge Fiori met Michel Normandeau (vocals and guitar) in a theatre music meeting in November 1972.
A single was also released at the time with the hit "Pour un instant" on the A-side and "100,000 Raisons" on the B-side, the latter was eventually included on the CD-reissue version of the album nearly 20 years later.
For this album, the band invited two guests to play on the sessions: Judi Richards, who handles the vocalizations on the instrumental "Histoires sans paroles" and Marie Bernard performing the theremin-like sounds of the Martenot waves on "En pleine face".
[14][15] Locat, who later revealed in an interview that he had not been permitted by Fiori to contribute his compositions to the band, announced his departure in August 1977, wanting to record a solo album.
Fiori teamed up with Richard Séguin to create the album Deux cents nuits à l'heure, which had been in development for four years and was finally released in May 1978, featuring several Harmonium members as session musicians.
After a full American tour failed to materialize in the spring of 1978, Harmonium was later invited to perform a handful of concerts in Berkeley and Los Angeles in September 1978, where the performance of material was filmed by a team from the National Film Board of Canada and released theatrically as Harmonium en Californie in October 1979.
[18][19] Without Fiori, Harmonium then comprised Valois, Farmer, Stanley, Subirana, and Fauteux, which together continued planning the fourth album, scheduled for release during the first half of 1979, but which ultimately never materialized.
The remastering reflected more closely the vision of Fiori, into fully open music compared to the original studio mix.
It was accompanied by the release of an extra song recorded live in 1977, called C'est dans le noir, available on iTunes.
[24] A remix from the original 16-track master tapes of the group's first album, titled Harmonium XLV was released in December 2019 which includes a different take of the hit Pour un instant.
[25] In 2020, Simon Leclerc scored a full orchestral version of the totality of Harmonium's music and recorded it with the Montreal Symphony Orchestra.