Change of Register

Definition: A developmental technique involving dramatic octave displacement of thematic material, moving low notes to extreme treble and treble notes to extreme low register through abrupt leaps, creating maximal registral contrast and textural transformation.

Messiaen's Treatment: Messiaen describes this as: "the low notes of the theme pass to the extreme treble, the treble to the extremely low, in abrupt leaps." He cites Alban Berg's use of this procedure in the Suite lyrique and passages from André Jolivet's Mana bearing evidence of analogous preoccupations (Example 127).

Augmentation combined with change of register will communicate "crushing power" to the theme (Example 128).

Modern Context: Change of register represents a twentieth-century developmental technique particularly associated with expressionism and modernist instrumental writing:

Historical development:

• Late Romantic: Occasional registral extremes for dramatic effect (Mahler, Strauss)
• Expressionism: Systematic exploitation of registral extremes (Schoenberg's Pierrot Lunaire, Berg's operas and chamber works)
• Post-war modernism: Registral displacement as primary developmental parameter (Webern, Boulez, Stockhausen)

Compositional applications:

• Klangfarbenmelodie: Timbre melody through registral/instrumental change (Schoenberg, Webern)
• Pointillism: Notes distributed across extreme registers creating disjunct textures
• Registral streaming: Different registers functioning as independent layers

Berg's Lyric Suite (1925–26) represents a key work in the development of this technique—thematic material undergoes systematic registral transformation, with extreme leaps creating expressive intensity. Messiaen's citation acknowledges Berg's influence and positions himself within the Second Viennese School's developmental tradition, despite his different harmonic language.

Jolivet (1905–1974), Messiaen's contemporary and founding member (with Messiaen) of La Jeune France group (1936), shared interests in non-Western music, ritualistic elements, and systematic compositional procedures. The reference to Mana (1935)—a set of piano pieces exploring magical/ritual themes—indicates shared aesthetic concerns and mutual influence within French modernist circles.

The combination of augmentation with registral change creating "crushing power" demonstrates the expressive potential of combining transformational techniques. Augmentation alone slows the theme, increasing its temporal weight; registral displacement to extremes adds spatial/registral weight; together they create maximum intensification—the theme becomes monumental, overwhelming.

This connects to Messiaen's interest in expressing "noble sentiments" and "religious sentiments exalted by theology" (Chapter I). The combination of temporal augmentation and spatial displacement can evoke transcendence, grandeur, or divine power—technical means serving theological/expressive ends.

Examples: Examples 127–128 demonstrate registral displacement and its combination with augmentation.