... Program NoteThe Sanctus is an aleatoric mass movement in which the pitches are selected by the performers and thedurations are cued by the conductor. The score is divided graphically into three pitch boxes, high, middleand low. The numbered vertical arrows are conductorTs cues for entrances, cutoffs, pitch changes. anddynamic changes. In the first section, no tempo or duration is specified except by horizontal spacing.Vertical arrows joined by a bar are to be executed in quick succession. At the beginnning, the pitches of thefour soloists (SATB) are individually selected according to the positions of the lines in relation to the pitchboxes. At 2, the respective choral sections enter individually at the unison. At 3, the choral sections glideat individual rates above and below the central pitch sustained by the soloist. The conductor may want todouble the central pitch after it has been established by the soloist. The choral parts should dwell on thecentral pitch from time to time, and should progress no further than a major third above and below it. Thecentral pitch changes at 11. The basses leap up an octave, the altos rise a half-step, the tenors go down awhole tone and the sopranos go down a fifth. Shortly after conductorTs cue 15, the basses begin a rapidfluctuation above and below the center pitch, agitato. The other parts repeat this in succession. At Al,the basses intone in unison on the center pitch while the other parts begin a gradually descenting glide tothe lowest note ( P.4), out of which the soprano and tenor and later the alto and bass glissando upwardsinto the high range.At letter B (p.7), a measured 4/4 has to be maintained for synchronization of the parts. In this section,the beat is equal to the single square box. For example, in the beginning alto part, ~oBe� is two beats, ~~ne�Tis one beat, odic� is six beats, etc. At. B6, the conductor once more cues the durations (oHosannaTT, etc.)