Alexander Scriabin - Prometheus or The Poem of Fire (with score) 

Many thanks to Thomas Van Dun for his preparation of this score video. / @thomasvandun
Prometheus or The Poem of Fire / Symphony no. 5 - for orchestra, chorus and light organ
Written by Alexander Scriabin in 1910.
Performed by the Chicago Symphony Orchestra and the Chicago Symphony Chorus, conducted by Pierre Boulez
'This was the last orchestral work written by Scriabin, and it is widely regarded as his most radical large composition and one of his greatest masterpieces. From about 1903 onward Scriabin was drawn toward the study of theosophy, and he gradually became more daring stylistically as well. The Symphony No. 5 reflects his increasingly eccentric artistic persona: it attempts to take the first step toward uniting all art forms, as well as to express certain religious and philosophical ideas.
The work's harmonic language is advanced -- but this was only another step along the way for Scriabin, who had already fashioned a style well beyond the average listener's comprehension in his own day. The composer never realized a crucial part of his conception: in the score he specifies that certain colours should flood the concert hall during performance, projected by a "clavier à lumières," a keyboard instrument not even in existence at the time. Scriabin associated keys with colors -- F major, for example, he linked with hell and saw as blood-red. At the March 15, 1911, premiere -- led by Koussevitsky -- the music was given without the accompanying colour projections. A 1915 New York performance provided the colours for the audience, but by projecting them on a screen -- a disappointing compromise for the composer.
The score also calls for a huge orchestra (eight horns, five trumpets, and other large sections), piano, organ, and chorus, whose members are instructed to wear white robes and sing with closed lips. Scriabin attempts to unify sound and color, as well as to convey his mystical and philosophical ideas via his Prometheus, a mythological character who symbolizes rebellion against God. The composer associates him with Lucifer, called the bringer of light, thereby introducing the element of bright color, infernal images, and much else into the work.
Scriabin bases the composition on a single chord of six notes, from which emerges the opening theme on muted horns and virtually all subsequent thematic material. Prometheus begins with music depicting Chaos, and then turns to a variety of other subjects that include joy, eroticism, human passion, and ego. Near the end, when the music reverts back to the gray mists of the opening, there is a section entitled "Dance of the Atoms of the Cosmos."
The whole work evokes ethereal and otherworldly images. The music has an aura of the surreal throughout, with thematic development taking unexpected detours and instrumental colours often brighter and more intense than the colours any machine could project in a concert hall. The expressive language of Prometheus lies somewhere between Stravinsky's The Firebird -- a work written at about the same time -- and some of the early 12-tone works. Still, this is tonal music, masterfully crafted and hardly offensive to the modern ear. It is also pure Scriabin from first note to last.' - Robert Cummings