isopolyphonic

Isopolyphonic is a term used in music theory and ethnomusicology to describe a particular kind of polyphonic texture. The word derives from iso- "same" and polyphonic "many voices". There is no universally accepted definition, and the term appears only sporadically in scholarly literature.

In one common usage, isopolyphony denotes textures in which two or more voices articulate the same melodic line, either in unison or in parallel motion at fixed intervals such as octaves or fifths. This yields a reinforced, somewhat monophonic-sounding texture despite the presence of multiple parts. In another sense, the term is used to describe voices that retain identical rhythmic-melodic content with little independent development, producing a dense, uniform sonority. Some authors reserve the term for cases where the parallelism is deliberate and structurally central, akin to a formal canonic mechanism executed with minimal divergence.

Because of differing usages, some scholars prefer related terms like "parallel polyphony" or "isophony" or simply describe the texture without labeling it as isopolyphonic. The concept is most often encountered in discussions of non-classical or traditional musics, early polyphonic practices, or analytic glossaries rather than as a standard category in modern music theory.

See also: polyphony, homophony, heterophony, canonic texture, parallel motion.