Scale masks from traditions outside Western common practice, addressable by
scaleByName exactly as NAMED_SCALES is.
They are kept apart from NAMED_SCALES because chord-scale theory is a
Western practice: a raga offered as the scale over an augmented major seventh
would read as an answer while being a category error. Nothing else separates
them — a KeyScale built from one of these masks behaves like any other.
Three limits are worth stating plainly rather than leaving a caller to
discover:
A twelve-bit mask can only hold what twelve-tone equal temperament can
express. The maqamat that turn on half-flat degrees — Rast, Bayati, Saba,
Sikah — are therefore absent rather than approximated, and the entries that
are here are not tuned the way their traditions tune them. Cents, arbitrary
equal divisions and just ratios live in the tuning module.
A thaat is the pitch material a raga draws on, not the raga: ascent and
descent, the notes a phrase leans on, and the ornaments belong to the raga
and have no place in a mask.
Several of these sets are the same pitch classes as a Western mode. The
name is what carries the tradition, so pass the name, not the mask,
wherever the tradition matters (scaleSystemOf reads both).
The second limit is the general case: an entry is the pitch material a
tradition names, never the modal system built on it. A maqam is assembled
from ajnas that are transposed and exchanged as a phrase moves, and Koizumi's
tetrachord theory describes the Japanese scales by the nuclear tones framing
each tetrachord, so miyakoBushi and minyo differ by tetrachord type — a
difference their pitch classes record without explaining. Reach for these
entries when a pitch set is what is wanted.
Scale masks from traditions outside Western common practice, addressable by scaleByName exactly as NAMED_SCALES is.
They are kept apart from NAMED_SCALES because chord-scale theory is a Western practice: a raga offered as the scale over an augmented major seventh would read as an answer while being a category error. Nothing else separates them — a
KeyScalebuilt from one of these masks behaves like any other.Three limits are worth stating plainly rather than leaving a caller to discover:
The second limit is the general case: an entry is the pitch material a tradition names, never the modal system built on it. A maqam is assembled from ajnas that are transposed and exchanged as a phrase moves, and Koizumi's tetrachord theory describes the Japanese scales by the nuclear tones framing each tetrachord, so
miyakoBushiandminyodiffer by tetrachord type — a difference their pitch classes record without explaining. Reach for these entries when a pitch set is what is wanted.