MUS 312 Form & Analysis
N. The Roles of Chance and Choice in 20th-Century
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There has been a general tendency in Western music to restrict
the performer's options ever more closely, and at the same time an
increasing dedication to honoring the composer's intentions at the
expense of the performer's creativity. However, an important
force in music in the second half of the 20th century has moved in
just the opposite direction, toward less control by the composer and
more creative responsibility for the performer. This new
responsibility can range from making an insignificant decision to
shaping all aspects of a piece. In either case, the composer
deliberately leaves something unspecified, up to chance or to the
whim of the performer. Two terms for music of this sort are indeterminacy
and aleatory, which mean essentially the same thing.
These two approaches--chance in composition and choice
in performance--form the two related branches of experimental
music, a term that is appropriate for any music in which the
final product is deliberately kept beyond the control of the
Chance in Composition
In order to allow chance to play a part in composition, the
composer must decide what aspects of the work are to be decided by
chance and what the range of probabilities of each aspect should be.
The most influential composer to make extensive use of chance in
composition is American composer John Cage.
Only the imagination limits the variety of means which may be
used by a composer to determine the element of chance: I-Ching
(Chinese treatise on probabilities), imperfections in paper, even
machine gun fire aimed at manuscript paper!
Computers have been used to some extent in this regard, since
they can be programmed to produce an apparently random series of
numbers within a specified range and to use those number in
decision-making processes. Using a computer, the probabilities
can sometimes be quite complex.
A very simply example may be as follows:
Suppose we want to generate a melody that will conform to the
- Use only the notes C, E and G.
- Allow no repeated notes.
- Use fewer G's than C's or E's.
- Distribute the C's and E's evenly.
The following table would tend to produce such a melody, although
we still must specify its length and the first note. (For
instance, if C is the most recent note generated, then the next note
will probably be E [75%], but might be G [25%].)
Conditional probabilities can be nested to any depth, with the
result that the selection of a particular event may depend upon the
result of the last several decisions.
Lejaren Hiller is a composer whose name is often associated
with computer composition. Together with Leonard Isaacson,
he composed the first serious computer piece, the Illiac Suite
for String Quartet, in 1957. Other composers associated
with computer probability composition include: Iannis Xenakis,
Larry Austin (a USF prof!), Barry Vercoe.
Choice in Performance
Aleatory in performance can range all the way from the most
insignificant detail to the entire shape of a piece. In the
latter case, the result may be an entirely different sound each time
the piece is performed.
The elements of composition that may be left up to the performer
include the following:
- Medium (instrumentation)
- Expression (dynamics, etc.)
- Duration (rhythm & tempo)
Composers interested in allowing the performer to have more
freedom frequently omit expression marks, etc.
Some composers wish to exercise only a limited amount of control
by leaving durations up to the performer. In such cases, proportional
notation is used, where the spacing of the notes on the page
indicates their approximate durations.
A simple example of pitch indeterminacy is the instruction
"as high as possible." More extended examples often
show the general contour of a desired line.
The usual method of leaving the form of a work unspecified, short
of total improvisation, is to allow the performer or conductor to
choose the order in which sections of a piece will be performed, or
whether they will be performed at all! This approach to form
is sometimes called open form or mobile form.
Some composers associated with pieces which utilize performer
indeterminacy are: Stockhausen, Morton Feldman, Lukas
Foss, Cornelius Cardew, Witold Lutoslawski.
Graphic Scores & Text Scores
A graphic score is one in which conventional musical
notation has been abandoned in favor of geometric shapes and designs
that suggest more or less how the music is to be performed.
Some composers associated with graphic scoring are: Feldman,
Martin Bartlett, Robin Mortimore.
A text score is one that consists only of words. The
text usually provides instructions for an improvisation, but it may
do little more than set a mood. Some composers associated with
text scores are: Stockhausen, Christian Wolff, Dick
Music on the Fringe
In the 1960s and 1970s especially, a number of composers wrote
pieces that seem to many musicians to push the limits of what can be
called "music." Traditional definitions of music
often include references to organized sound and to the expression of
ideas and emotions, but some works challenge these notions.
Some composers associated with "fringe music" are:
Dick Higgins: includes works where persons simply
listen to environmental sounds.
Pauline Oliveros: environmental theater piece that uses
an entire city or university as its performing stage.
Mortimore: one piece contained the instructions:
"Play until 2000 A.D."
Paul Ignace: retitles works, such as a "Symphony
No. 2," which is a repeat of Symphony No. 1, heard the
David Cope: "danger music," which suggests
Takehisa Kosugi: instructions include: "scoop out
one of your eyes five years from now."
Philip Corner: "One Antipersonnel-Type CBU Bomb
Will Be Thrown into the Audience."
Experimental music, in which the composer consciously abdicates
control over the compositional process or the performance, or both,
has been an important element of music in the second half of the
20th century. Chance in composition has involved the use of a
number of decision-making techniques, including the I-Ching,
while the computer has made practicable aleatoric compositions that
are much more complex. The element of chance--or, from the
performer's viewpoint, choice--has been even more influential in the
performance of music than in composition. The improvised
portions of a score may be insignificant, or improvisation may be
the major element of interest in the work. New notations have
been devised for indeterminate music, including proportional and
graphic notation; text scores dispense with notation entirely.
Finally, a number of "fringe" movements have ranged from
the absurd to the violent, calling into question our notion of what
music really is.
Minimalism & Neoromanticism
Minimalism and neoromanticism are two important trends in more
recent music. They both developed first in the United States
and only later were adopted by European composers.
Minimal music, also called process music, phase
music, pulse music, systemic music, and repetitive music,
may have had its roots in some of the works that Cage, Wolff, and
Feldman composed in the 1950s, but the first important example of
what has become known as minimalism was Terry Riley's In C
Some of the characteristics of minimalist music include:
- Restricted pitch and rhythm materials
- Tonal (or neotonal) language
- Use of repetition
- Phasing (moving out of sync)
- Drones of ostinatos
- Steady pulse
- Static harmony
- Long duration
Many of these aspects are also found in some kinds of Eastern
music, as is the meditative quality characteristic of many
minimalist works. Riley, Steve Reich, and Philip
Glass, the three Americans most closely associated with
minimalism, all studied Eastern music. Glass' study of the
improvisations of Ravi Shankar was especially important in the
development of his mature style.
Neoromanticism is the term used for
"romantic-style" music usually superimposed on an atonal,
avant-garde background, or swallowed up in a collage of other
quotations in a "stream-of-consciousness style."
George Rochberg is a composer whose name is perhaps most
closely associated with this style, although there are many
others: David Del Tredici, Krzysztof Penderecki,
Frederic Rzewski, Ladislav Kupovic.
While the post-serial avant-garde tradition has not died out, it
has certainly met with serious opposition in the forms of
indeterminacy, minimalism, and neoromanticism. Indeterminacy
was a reaction against the total control that is the basis for
serialism. Minimalism opposes the atonal ideas of the
incessant recycling of pitch material, of constant variation, and,
of course, of atonality itself. Neoromanticism does these
things, too, but it represents also a complicated relationship
between today's composers (and listeners) and the music of the past.
And so 20th-century music continues as it has always been--a
maddening but fascinating collage of approaches and materials, a
period without a style.
Popular Music Form
These are the primary sections found in many pop songs.
Naturally, there are typically repetitions of verses and
choruses. The bridge is a modulating section.
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