Third and Seventh (Grave) Modes belong to the Enharmonic Scale. The Enharmonic Scale has two interval sizes: 12-6.

Sixth Mode interval sizes:
12-12-6-12-12-6-12
Ni-Pa-Vou-Ga-Di-Ke-Zo'-Ni'

There are 72 "comas" or micro steps in an octave, For example, a full tone is equal to 12 comas. The distance from Ga(F) to Di (G) is 12 comas. However, the distance from Ke(A) to Zo(B) is 6 comas.

The Enharmonic Scale tuning is similar to the equal-tempered scale:

A special signature (Martyria) is written to indicate the mode and starting pitch. Also, the modulation signs (Phthorai) are written to indicate the transition from one mode to another.

The Enharmonic Scale

Illustrations:

Martyria of the Enharmonic Scale:

Pthora of the Enharmonic Scale:

The Enharmonic Scale in both Psaltic and staff notation:

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