The Forty Part Motet (2001), a sound installation by Janet Cardiff (Canadian, born 1957), was the first presentation of contemporary art at The Cloisters. Regarded as the artist’s masterwork, and consisting of forty high-fidelity speakers positioned on stands in a large oval configuration throughout the Fuentidueña Chapel, the fourteen-minute work, with a three-minute spoken interlude, continuously played an eleven-minute reworking of the forty-part motet Spem in alium numquam habui (1556?/1573?) by Tudor composer Thomas Tallis (ca. 1505–1585). Spem in alium, which translates as “In No Other Is My Hope,” is perhaps Tallis’s most famous composition. Visitors were encouraged to walk among the loudspeakers and hear the individual unaccompanied voices—bass, baritone, alto, tenor, and child soprano—one part per speaker—as well as the polyphonic choral effect of the combined singers in an immersive experience. The Forty Part Motet is most often presented in a neutral gallery setting, but in this case the setting was the Cloisters’ Fuentidueña Chapel, which features the late twelfth-century apse from the church of San Martín at Fuentidueña, near Segovia, Spain, on permanent loan from the Spanish Government. Set within a churchlike gallery space, and with superb acoustics, it has for more than fifty years proved a fine venue for concerts of early music.

Of the work, Cardiff says,

“While listening to a concert you are normally seated in front of the choir, in traditional audience position. With this piece I want the audience to be able to experience a piece of music from the viewpoint of the singers. Every performer hears a unique mix of the piece of music. Enabling the audience to move throughout the space allows them to be intimately connected with the voices. It also reveals the piece of music as a changing construct. As well I am interested in how sound may physically construct a space in a sculptural way and how a viewer may choose a path through this physical yet virtual space. I placed the speakers around the room in an oval so that the listener would be able to really feel the sculptural construction of the piece by Tallis. You can hear the sound move from one choir to another, jumping back and forth, echoing each other and then experience the overwhelming feeling as the sound waves hit you when all of the singers are singing.”

http://www.metmuseum.org/exhibitions/listings/2013/janet-cardiff