Phyllis Stevenson (1922–2000) — Spectral Prelude No. 6 (1985) for organ
Phyllis Stevenson (1922–2000) lived most of her life fairly reclusively in North Dakota, where she taught music and composed a number of musical works. Her music was particularly inspired by the work of Charles Ives, Claude Debussy, and American minimalism. In particular, she wrote a large number of pieces for the piano and for her own instrument, the tuba.
The composer wrote the following notes about this piece:
"Spectral Prelude No. 6" (1985) is one of twelve such pieces I have written, each scored for a different solo instrument. Each prelude is based, very simply, on the harmonies of the overtone series of a particular fundamental. In the case of the organ, it is the pedal's lowest C. This piece is also the simplest conceptually of the spectral preludes, since the full organ's basic tone color is so rich in overtones to begin with. As with all the preludes, the piece gradually unfolds the entire pitch spectrum of the overtone series to lead to the saturation of the total chromatic. Along the way, it fixates on various intervals -- in this piece it is the tritone in particular that becomes the source of a major/minor ostinato. Finally, at the very end, over the fundamental C held in the pedals, we get the full 12-note total chromatic in crazed arpeggios across the keyboard."