I have often found that writing a piece for a specific acoustic and architectural space can provide the composer with enough initial aural stimuli to set off a torrent of musical ideas. I visited York Minster late last year and came away with the beginnings of a strange "antiphonal" sound world that I felt would suit the grandeur of this magnificent building.
My solution was to take as my raw material Hildegard of Bingen's monody hymn "Ave Generosa". The fluidity and invention of the original musical line became the starting point for a series of compositional decisions. I began by melodically developing the original monody and then subjecting it to a process of "spatialised" heterophony where the line is fractured and heard at six different speeds. Through a process of juxtaposition, Hildegard's original and my reworking are realised by using an amplified ensemble of 12 voices (4 sopranos, 4 altos and 4 tenors) which are electronically routed to any of the 7 loudspeaker locations within the Minster, creating a kaleidoscope of changing vocal perspective. The voices are accompanied by a large instrumental ensemble which sets up a distant veiled resonance to the chant throughout the duration of the piece.