27 Edo + 28 Edo Polymicrotonality over a 27:28 Polyrhythm | Lunar Mansion Cycles

The sonification of two lunar mansion correspondence systems as they cycle through the zodiac.

The systems:

The 27 equal divisions of the Indian, or Vedic Astrology, Nakshatra system

The 28 equal divisions of the Arabic Manazilu ʾl-Qamar

The 12 equal division of the Sidereal Zodiac

The method:

Both systems begin with 0° Aries (Sidereal). This became the root note for each cycle [G3 was chosen arbitrarily]. To construct the arpeggio through the 27 and 28-note rows, a non-repeating note cycle was determined for each, in the same way the Circle of 5ths is created. Since the Circle of 5ths in 12 Edo is determined by a coprime cycle [7/12], it comparatively becomes [16/27] in 27 Edo and [17/28] in 28 Edo.

Edo, or EDO, stands for Equal Divisions of the Octave.

The 27 and 28-note arpeggios are programmed to meet up again simultaneously on the one, 0° Aries, as they complete their 27:28 polyrhythm cycle (along with the 12 Edo Circle of 5ths for the Zodiac signs)