Revolutions In Classical Music Pt. 3 -
The four organs harmonically expound a dominant eleventh chord (E–D–E–F♯–G♯–A–B), dissecting the chord by playing parts of it sequentially while the chord slowly increases in duration from a single 1/8 note at the beginning to 200 beats at the end. The process of increased augmentation is accomplished first by causing notes to sustain after the chord, and then notes start anticipating the chord. As the piece progresses, this "deconstruction" of the chord emphasizes certain harmonies. At the climax of the work, each tone sounds almost in sequence. A continuous maraca beat serves as a rhythmic framework.
Reich describes the piece as "the longest V–I cadence in the history of Western Music" the V (B–D–F♯) and I (E–G♯–B) chords being contained within the one chord: "You'll find the chord in Debussy and Thelonious Monk – the tonic on top and the dominant on the bottom." (from Wikipedia)
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