Abstract Improvisation often seems to have a negative reputation among ‘serious’ composers, since it is considered to be characterised by an artistic looseness in contrast to classical compositions, which are meticulously notated and require disciplined observance from musicians. ‘Comprovisation’ is a portmanteau word coined by the American composer Richard Dudas (2010) to describe notated compositions that include improvisation. The instrumental parts of Nigerian Igbo Choral Art Music (ICAM) are highly structured and interwoven with the notated choral part. While such parts could be considered ‘composition’, they are often left un-notated by composers, thus allowing musicians to make their own creative contributions to the final work. The process whereby ICAM is comprovised allows the musical form (in both its choral and instrumental parts) to retain freshness as well as gravitas in the art music sphere. Many studies have been conducted on ICAM, primarily focusing on its history, development and compositional principles, such as the relationship between melody and rhythm, accents and the intonation of Igbo texts. The existing research does not, however, explore the critical role that un-notated instrumentation plays in the final musical product and the genre’s ontology. This article addresses this gap by arguing that the instrumental part of ICAM is a well-structured process that is integral to the genre, albeit un-notated.

中文翻译：

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伊博合唱艺术音乐 (ICAM) 中的“合唱”：介绍

摘要 在“严肃的”作曲家中，即兴创作似乎经常受到负面评价，因为与古典作品相比，它被认为具有艺术上的松散性，古典作品经过精心标记并需要音乐家严格遵守。“Comprovisation”是美国作曲家 Richard Dudas (2010) 创造的一个混合词，用来描述包括即兴创作的乐曲。尼日利亚伊博合唱艺术音乐 (ICAM) 的器乐部分高度结构化，并与带符号的合唱部分交织在一起。虽然这些部分可以被认为是“作曲”，但作曲家通常不会对它们进行注释，从而允许音乐家对最终作品做出自己的创造性贡献。ICAM 的合成过程允许音乐形式（在其合唱和器乐部分）在艺术音乐领域保持新鲜感和庄严感。已经对ICAM进行了许多研究，主要集中在其历史、发展和组成原则，例如旋律与节奏、口音和伊博语文本的语调之间的关系。然而，现有的研究并没有探索未标注乐器在最终音乐产品和流派本体中所起的关键作用。本文通过论证 ICAM 的工具部分是一个结构良好的过程来解决这一差距，尽管没有注释，但它是该类型不可或缺的一部分。发展和组成原则，例如旋律和节奏之间的关系、口音和伊博语文本的语调。然而，现有的研究并没有探索未标注乐器在最终音乐产品和流派本体中所起的关键作用。本文通过论证 ICAM 的工具部分是一个结构良好的过程来解决这一差距，尽管没有注释，但它是该类型不可或缺的一部分。发展和组成原则，例如旋律和节奏之间的关系、口音和伊博语文本的语调。然而，现有的研究并没有探索未标注乐器在最终音乐产品和流派本体中所起的关键作用。本文通过论证 ICAM 的工具部分是一个结构良好的过程来解决这一差距，尽管没有注释，但它是该类型不可或缺的一部分。