SOURCE MATERIAL was composed for EXAUDI, under the supervision of James Weeks. In a similar fashion to SYNTAX, SOURCE MATERIAL is a work which draws heavily on notions of historical enquiry. With this work, it was important to me to use a choral ensemble in a way which did not ignore the vast history of choral music. Many questions emerged at the start of the writing process, such as whether historical enquiry was possible in music without the use of pastiche, or whether it was possible to write a truly new work for vocal ensemble in today’s world.
It became clear that I wanted to work with historical vocal material in a new way. I was deeply interested by an idea arrived at through research into medieval and Renaissance vocal music: that developments in polyphony are an apt metaphor for societal developments. Vocal lines existing independently can be seen to represent individual sovereignty, while their contrapuntal combination represents how individuals within a society interface with a community. Additionally, religious history became a significant factor in the initial planning phase. I became interested in taking the monophonic roots of early music and creating a vocal ensemble piece that generated polyphony in a contemporary way.
I began by collecting a series of monophonic vocal compositions to form a corpus of works. I was inspired by the ideas of Michael Finnissy regarding transcription, specifically the concept of ‘writing through’ a particular composer. I wanted to create a modern ‘transcription’ of multiple works at once. I performed an intervallic analysis on several notated choral works, a process similar to the treatment of training data in machine learning. I was interested to see what kind of composition could emerge from ‘training’ a computer algorithm on an existing corpus. Each piece was analyzed, and a tally was kept of how often each interval occurred, including unisons.
Once the intervallic frequencies were collected, the results were aggregated into a single list that formed the basis for a Supercollider algorithm. A melody was generated by choosing a random starting note, with each subsequent interval selected at random from the weighted list derived from the source compositions. By analyzing the intervals of the source material, the probability of an interval being selected by the algorithm was directly related to its frequency in the original corpus. In this way, the source pieces were abstracted and combined into a new, single melody.
To translate this melody for the ensemble, I orchestrated it across the voices based entirely on their respective ranges, allowing the physical limitations of the singers to dictate the texture. All surrounding material in the other voices consists of different expressions of this same melody; notes are either held as drones or the melody is rhythmically augmented. I also introduced slight variations in tempo to disrupt the rhythmic regularity implied by the note durations, creating barely perceptible disruptions to the metric surface of the music.
The text used for the piece is the Kyrie eléison and Christe eléison. This text serves as a placeholder extracted from the very Gregorian chants and vocal pieces that informed the melodic material. It was my ambition that this text would contextualize the work and make the reference to religious tradition explicit. My enquiries into the beginnings of polyphony are represented here: the ensemble sings together, yet each performer maintains their own distinct representation of the shared melodic line.