Triple Quartet is for three string quartets. For Kronos (or any other single string quartet) to perform the piece they must pre-record quartets two and three and then play the quartet one part along with the pre-recorded tape. Alternatively, the piece can be played by 12 or more string players with no tape.
The piece is in three movements (fast-slow-fast) and is organized harmonically on four dominant chords in minor keys a minor third apart: E minor, G minor, B-flat minor, C-sharp, minor, and then returning to E minor to form a cycle. The first movement goes through this harmonic cycle twice with a section about one minute long on each of the four dominant chords. The result is a kind of variation form.
Rhythmically the first movement has the second and third quartet playing interlocking chords while the first quartet plays longer melodies in canon between the first violin and viola against the second violin and cello.
The slow movement is more completely contrapuntal with a long slow melody in canon eventually in all 12 voices. It stays in E minor throughout.
The third movement resumes the original fast tempo and maintains the harmonic chord cycle, but modulates back and forth between keys more rapidly. The final section of the movement is in the initial key of E minor, and there the piece finally cadences.
Triple Quartet was commissioned by and is dedicated to the Kronos Quartet.
— Steve Reich