Lux Aeterna is scored for Flute (Piccolo), Bb Clarinet (Bass Clarinet), Oboe, Bassoon (Contra-Bassoon), French Horn, Trumpet in C, Tenor Trombone, Soprano Voice, Alto Voice, Tenor Voice, Bass Voice, 2 Violins, Viola, Cello and Double Bass. The piece lasts 17-18 minutes. The text, in its original Latin, is from the Requiem Mass. The pitch material for the four voices is directly derived from the original Gregorian Chant (B, C#, D, E, F#, G, A). The primary pitch materials for the instrumental ensemble are drawn from the overtone series, with the fundamental of B natural. As found in the natural overtone series, the chords produced in this composition include microtones found both naturally from the series along with microtones added by the composer to create harmonic friction. This treatment of microtonal materials is juxtaposed with the “pure” nature of the B minor modal scale sung by the 4 vocalists.
Lux Aeterna uses the performance space so that the sixteen performers and conductor surround the audience in an oval shape. Entrances of instruments are determined by their position around the audience and the way in which those sounds interact with one another across the space of the hall. The instruments are strategically placed so that timbres can be balanced in a specific way and the listener can hear the pitches blend in the acoustics of the hall. The goal is to create an immersive listening experience for the audience. Although there are some spectral techniques involved in this composition, no computers or software programs were used to analyze harmonic materials. The pitch material is either from the overtone series or the B minor scale. Essentially, the music is instinctually composed.