Perpetuum mobile

Perpetuum mobile (Latin, English pronunciation /pəːˌpɛtjʊəm ˈməʊbɪleɪ, ˈməʊbɪli), moto perpetuo (Italian and Portuguese), mouvement perpétuel (French), movimiento perpetuo (Spanish), literally meaning "perpetual motion", means two distinct things:

  1. pieces of music, or parts of pieces, characterised by a continuous steady stream of notes, usually at a rapid tempo
  2. whole pieces, or large parts of pieces, which are to be played repeatedly, often an indefinite number of times.

Contents

As a technique

A well-known example is the presto finale of Frédéric Chopin's Piano Sonata No. 2:

This figuration of rapid triplet quavers (eighth notes) continues for the duration of the movement.

For other examples, see Examples below.

As separate compositions

As a separate piece, a "Perpetuum Mobile" can be defined as a composition where (a large part of) the piece is intended to be repeated an (often not specified) number of times, without the "motion" of the melody being halted when a repeat begins. Canons are often intended to be performed in a moto perpetuo fashion (which, in that case, can be called canon perpetuus). In some cases the repeats of a "perpetuum mobile" piece are at a different pitch (while a modulation or a chord progression occurs during the repeatable part): some of the riddle canons of Bach's Das Musikalische Opfer are examples of this particular kind of Perpetuum Mobile/Canon Perpetuus.

Perpetuum mobile as a genre of separate musical compositions, was at the height of its popularity by the end of the 19th century. Such pieces would often be performed as virtuoso encores, in some cases increasing the tempo along the repeats.

Examples

"Perpetuum mobile" pieces of both kinds include:

19th century

19th-century examples of the "Perpetuum Mobile" genre include:

20th century

20th-century examples of the "Perpetuum Mobile" genre include:

21st century

21st-century examples of the "Perpetuum Mobile" genre include: