User:CellularAutomaton/Bitetradic

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A bitetradic scale is a heptatonic (or in certain cases smaller) scale created by constructing two tetrads, one starting on 1/1 and one ending at the period. A special variety, the tertian bitetradic scale, is specifically created with two tertian seventh chords and a period of 2/1. In a tertian bitetradic scale, the tetrads interlock to form the scale such that notes from the lower and the upper tetrad alternate. Any heptatonic scale can be analyzed as bitetradic; for example, the 12edo Ionian scale consists of a Maj7 chord on the 1/1 and a Min7 chord ending at 2/1.

Extensions to greater note sizes

It is possible to extend the bitetradic format to any odd size; instead of choosing two tetrads, one simply uses two pentads for nine notes, two hexads for eleven, et cetera.

Design principles

Tertian tetrads should be close to 0-2-4-6\7

If you're not using tertian tetrads, then try to assign each note of 7edo to one or the other tetrad

Examples of bitetradic scales

Any heptatonic scale could be considered bitetradic, but these scales were created specifically using the bitetradic method.

Rashtic

TBD