Binperoctave

Binperoctave is a theoretical musical concept used in speculative music theory and some microtonal discussions. It denotes an interval spanning exactly two octaves, corresponding to a frequency ratio of 4:1. In practice, the term is employed to explore pitch relations and perceptual questions that extend beyond the conventional octave boundary, and it may appear in discussions of constructed scales or tuning systems that treat octave equivalence more loosely.

Etymology and naming reflect its intended meaning: the prefix bi- signals “two,” while octave refers to the standard musical octave. The coinage is not standardized, and different authors may attach slightly different formal definitions depending on the theoretical context or tuning framework being discussed.

The binperoctave appears primarily in theoretical models rather than as a conventional musical interval used in performance. It provides a framework for examining how scales, harmonies, and timbral relationships behave when pitch relations cross multiple octaves in a single conceptual span. Some researchers use the idea to test how perceptual loudness, pitch spacing, and register transitions are affected by large-scale pitch relationships.

Notation and practical use vary with the tuning system under consideration. In 12-tone equal temperament, a binperoctave can be described as 24 semitones, i.e., two standard octaves. In other systems, it may be expressed differently according to the chosen division of the octave. Given its speculative nature, there is no universally adopted notation or usage.