The modes of limited transposition are musical modes discovered by the French composer Olivier Messiaen. In music, a mode is an ordered series of musical intervals, which, along with the key or tonic, define the pitches. ... Olivier Messiaen (IPA: or ; December 10, 1908 – April 27, 1992) was a French composer, organist, and ornithologist. ...

Based on our chromatic system of twelve notes, these modes are made up of several symmetrical groups, the last note of each group being the first note of the next. After a certain number of chromatic transpositions (i.e. up or down a semitone) each mode cannot be transposed further - the next transposition resulting in exactly the same notes as the first. In music, chromatic indicates the inclusion of notes not in the prevailing scale and is also used for those notes themselves (Shir-Cliff et al 1965, p. ... In music, transposition is moving a note or collection of notes up or down in pitch by a constant interval. ...

For example, the first mode contains notes C, D, E, F#, G#, A#, C; transposing this mode up a semitone gives C#, D#, F, G, A, B, C#. Transposing this up another semitone would give D, E, F#, G#, A#, C, D which is exactly what we started with.

Messiaen found ways of employing all of these modes both harmonically and melodically.

The first mode is divided into six groups of two notes each. It is transposable once. This is the whole-tone scale, quite widespread since Debussy. In music, a whole tone scale is a scale in which each note is separated from its neighbors by the interval of a whole step. ... Claude Debussy Claude Achille Debussy (August 22, 1862 – March 25, 1918), composer of impressionistic classical music. ... Image File history File links Messiaen-modus1. ...

The second mode, also called octatonic scale, is divided into four groups of three notes each. It is transposable twice, like the diminished-seventh chord. Here it is, expressed melodically: In music, a diminished scale is a scale in which the notes of the scale ascend in alternating intervals of a whole step and a half step. ...

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The third mode is divided into three groups of four notes each. It is transposable three times, like the augmented triad. Here it is, expressed melodically:

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Here are two modes of the fourth type, divided into two groups of five notes each, transposable six times, like the augmented fourth.

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The symmetry inherent in these modes (meaning no note can be percieved as the tonic), together with certain rhythmic devices, Messiaen described as containing "the charm of impossibilities." The tonic is the first note of a musical scale, and in the tonal method of music composition it is extremely important. ... Rhythm (Greek ρυθμός = tempo) is the variation of the duration of sounds or other events over time. ...