In the musical composition entitled Alla Luna, Richard Gibson uses a wide variety of choral textures , from intensely antiphonal passages with extensive divisi, through solo and accompaniment writing to playful contrapuntalism, while tracing the melancholic imagery of Giacomo Leopardi's poem of the same title. Written in 1819, Leopardi's Alla Luna describes an address to the moon in which the poet reflects upon the themes of lost opportunity, the transient pleasures of youth and the remembrance of past happiness. The split parts require a degree of musical independence from members within each section, but the sonorousness of the resultant harmonies are guaranteed to reward the extra effort required of individual choristers. The vibraphone was chosen as the perfect vehicle to accompany the aethereal lunar character of this piece, although a piano or electronic keyboard could be used as an adequate, albeit second-best substitute.
Although the vocal parts are identical in both versions, in the case of Op. 75 (b) there is strong reinforcement for the voices in the organ accompaniment, whereas the vibraphone accompaniment in Op 75 (a) gives extra emphasis to the melancholy lunar allure of the composition.
Quoique l’écriture vocale soit identique dans les deux versions, dans le cas d’opus 75(b), l’accompagnement des grandes orgues renforce davantage la polyphonie vocale de la composition, tandis que l’accompagnement du vibraphone de l’opus 75(a) contribue à l’atmosphère éthérée suggérée par le texte de Leopardi.