Lasting over 70 minutes and made up of 16 sonatas and four interludes, John Cage's Sonatas and Interludes is his most substantial work for his invention, the prepared piano. Completed in March of 1948, the work is dedicated to Maro Ajemian, who premiered it in New York City at Carnegie Hall on January 11, 1949.
Students of music history have probably seen photographs of pianos fitted by Cage with all sorts of foreign objects -- bits of rubber stuffed between strings, hammers fitted with tacks, perhaps even a wooden spoon poking out from the instrument's entrails at an odd angle. The so-called prepared piano, for which the Sonatas and Interludes are composed, provides the means by which a single instrument is able to evoke a wide variety of colors, timbres, and textures. The score, then, indicates not the sounds to be heard, but the action to be taken. Striking a particular key might produce a pitch, a hi-hat-like sizzle, or a wooden thump. Cage originally conceived the prepared piano for his 1938 work Bacchanale, in response to a request from dancer Syvilla Fort to provide music for a six-minute dance that had no budget and space for no more than one pianist. He used it again in A Book of Music (1944) and Three Dances (1945) before employing it in Sonatas and Interludes in 1948. The sound is immediately engaging, and because of the differences between various pianos and the numerous varieties of weather stripping, thumb tacks, and wooden spoons available, each performance or recording is distinct. The work conjures a world of sound that is variously serene, haunting, percussive, and surreal.
Each movement examines a particular emotion, with a palette drawn from the Indian tradition that includes heroism, eroticism, wonder, mirth, sorrow, fear, anger, and tranquility. Another important principle at work in the Sonatas and Interludes is that of micro/macrocosmic structure. In short, this means that local elements of the structure reflect the overall form of the piece. We can look at the first sonata in the series as an example. Explaining micro/macro structure requires what is perhaps a frightening amount of math, but reveals a very interesting principle at work. The base unit of this structure is a phrase consisting of seven beats. The first section of the bipartite sonata consists of two phrases, each with a length equivalent to seven measures in 2/2 time, or 28 quarter notes -- making the entire first section, with the notated repeat, 112 quarter notes long. The second section also consists of two phrases, but each of these is only 21 quarter notes long, the equivalent of seven measures in 3/4 time -- making the second section, with its repeat, 84 quarter notes long. This creates a structural four-to-three ratio, and makes the total length of the work, then, 196 quarter notes -- the equivalent of seven times seven measures in 2/2. Thus the length of each phrase resonates with the length of the entire work, and the parsing of seven into four and three gives the work its principal formal division. By composing within this carefully controlled structure, Cage is free to make uncontrolled decisions of pitch, rhythm, and timbre in the moment-to-moment, while maintaining an overarching holistic continuity.