TWENTIETH- - Synapse Music

150 Form in Twentieth-Century Music
line makes its way through three different (but related) twelve-tone "sets'-' This bass line,
first heard in mm. 15- 23, serves as the passacaglia theme for the movement.
EXAMPLE 7-2 Hindemith: String Quartet No.4, Op. 32 (1921), IV, mm. 1-8 (© by B. Schott', Soehne.
Mainz, 1924. Copyright renewed. All rights reserved. Used by pennission of European American Music
Distributors Corporotion, sole U.S. and Canadian agent for B. Schott's Soehne, Moinz.)
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Another example is Crumb's "Voices from Corona Boreali s" from his Makrokosl1ws,
Vol. II (1973) (K-G, p. 585), which uses a sixteen-note passacaglia theme in the upper register.
The use of isorhythms (review Chapter 6, p. 133) can be thought of as an extension
of the passacaglia principle. This is especially true when there is a pitch pattern associated
with the rhythmic pattern, as in the "Crystal Liturgy" from Messiaen's Quartet/or the End
a/Time (1941) (TUR, p. 511). Of course, the pitch pattern (the color) must not be the same
length as the rhythmic pattern (the lalea), or an ordinary ostinato wo uld result. In the Messiaen
work the rhythmic pattern contains 17 attacks and the pitch pattern contains 29 notes
(10 different pitch classes), so the rhythmic pattern would have to be repeated 29 times before
the beginnings of the two patterns would again coincide (because 493 is the lowest
common multiple of 17 and 29). Messiaen stops the process long before that point.
CANON AND FUGUE
Canon and fugue are not "forms" in the sense that rondos and sonatas are. Instead, they are
contrapuntal procedures that can be cast in any of a number of form al designs. Nevertheless,
musicians customarily have referred to both "homophonic forms" and "contrapuntal
forms," and it will be convenient in this chapter to follow that tradition.
The canon, a form that saw relatively little use in the century and a half after Bach,
has enjoyed a new popularity among twentieth-century composers. Whole sets of canons
have been written, such as Webern's Five Canons, Op. 16 (1924) (WEN, p. 271), and
canons frequently appear as a major portion of a longer work, examples being the trio of
the minuet from Schoenberg's Suite, Op. 25 (1923) (WEN, p. 177), and the second movement
of Webern's Variations for Piano, Op. 27 (1936) (BUR, p. 485). In both of these
works, the canonic imitation happens to be by contrary motion. The uninformed listener
would almost certainly be unaware of the canon in the Webern work, and the same would
be true of the sixth movement of Arvo Part's Magnificat Antiphons (1988) (K-G, p. 591), in
which a canon by augmentation is hidden in the Soprano II and Tenor II parts. Canons also
frequently appear as passages in otherwise noncanonic movements. For instance, although
Schoenberg's "Summer Morning by a Lake," Op. 16, No. 3 (1909) (BUR, p. 424), is not a
canon, it contains canonic passages, two of the clearest being mm . 3-9 and mm. 32-38.
Much of the challenge in writing a canon in the tonal idiom is to control the dissonance
while at the same time creating harmonic interest. To a certain extent these difficul-