Zygos changes the structure of the plagal 4th 5chord as follows:
The dominant grades ni, vu, di remain unaltered while pa raises towards vu by an enharmonic diesis
and ga approaches di, resulting in ga-di=Minimal tone.
In moria
plagal 4th
ni-12-pa-10-vu-8-ga-12-di =42
zygos
ni-15-pa-7-vu-12-ga-8-di =42
And most accurately in Delphic Units
(665/Octave, 113/Major tone, 88/Minor tone, 75/Minimal tone, 63/Apotome, 50/Leima, 25/Enharmonic diesis):
plagal 4th
ni-113-pa-88-vu-75-ga-113-di =389 Delphic Units
zygos
ni-138-pa-63-vu-113-ga-75-di =389 Delphic Units
AK
