contributed articles

DoI: 10.1145/1965724.1965742

Non-specialists may be disappointed that composition includes seemingly arbitrary, uninspired formal methods and calculation.c What we shall see here is that calculation has been part of the Western composition tradition for at least 1,000 years, This article outlines the history of algorithmic composition from the pre- and post-digital computer age, concentrating, but not exclusively, on how it developed out of the avant-garde Western classical tradition in the second half of the 20th century. This survey is more illustrative than all-inclusive, presenting examples of particular techniques and some of the music that has been produced with them.

A Brief history

Models of musical process are arguably natural to human musical activity. Listening involves both the enjoyment of the sensual sonic experience and the setting up of expectations and possibilities of what is to come: musicologist Erik Christensen described it as follows: “Retention in short-term

BY MIChAEL EDWARDS
Algorithmic
Composition:
Computational
Thinking
The composer still composes but also gets
to take a programming-enabled journey of
musical discovery.
in Music

in the West, the layman’s vision of the creative artist is largely bound in romantic notions of inspiration sacred or secular in origin. Images are plentiful; for example, a man standing tall on a cliff top, the wind blowing through his long hair, waiting for that particular iconoclastic idea to arrive through the ether.a Tales, some even true, of genii penning whole operas in a matter of days, further blur the reality of the usually slowly wrought process of composition. Mozart, with his celebrated speed of writing, is a famous example who to some extent fits the cliché, though perhaps not quite as well as legend would have it.b

 

a I’m thinking in particular of Caspar David Friedrich’s painting From the Summit in the Hamburg Kunsthalle.

b Mozart’s compositional process is complex and often misunderstood, complicated by myth, especially regarding his now refuted ability to compose everything in his head15 and his own statements (such as “I must finish now, because I’ve got to write at breakneck speed—everything’s composed—

but not written yet” in a letter to his father, Dec. 30, 1780). Mozart apparently distinguished between composing (at the keyboard, in sketch-es) and writing (preparing a full and final score), hence the confusion about the length of time taken to write certain pieces of music.

c For example, in the realm of pitch: transposition, inversion, retrogradation, intervallic expansion, compression; and in the realm of rhythm: augmentation, diminution, addition.

 

key insights

Music composition has always been guided by the composer’s own computational thinking, sometimes even more than by traditional understanding of inspiration.

Formalization of compositional technique in software can free the mind from musical and cultural clichés and lead to startlingly original results.

Algorithmic composition systems
cover all aesthetics and styles,
with some open-ended variants
offering an alternative to the fixed,
never-changing compositions that for
most of us define the musical limits.

IllustratIon By stuDIo tonne