5a: Triadic Voice-Go-Round

Once you understand the mechanical construction of the diatonic modes from the theory page as maximally even subsets of the regular 12-tone system, you may apply the same idea to the construction of the 21 inversions of the seven diatonic triads. The lower movie is more suggestive with regard to this analogy, while the upper movie shows, how to play the example on the SolFa Mode-Go-Round. Basically - on the basis of the seven scale degrees - you may think of a rotating triangle, whose vertices are moved one by one rather than simultanously. In a more refined way - on the basis of the 21 tone roles (three tone roles for each scale degree) - you may literally think of a rotating triangle,

Think of the inversions of triads as 3-tone modes in a world with seven (equally distributed) steps.

Instead of seven Modes with seven tones (Ionian, Dorian, Phrygian, Lydian, Mixolydian, Aeolian, Locrian) one has three modes with three tones:

  • Root position (5/3 Chord)

  • First Inversion (6/3 Chord)

  • Second Inversion (6/4 Chord).

What would be the intrinsic "solmization syllables" in such a world of triadic modes? Help: Remember that the syllables do, re, mi, fa, so, la, ti refer to unique neighborhoods in the step interval pattern. Do is preceded from below by a half step and it followed above by two steps and one half step. Re is preceded from below by a full step and it followed above by a step, a half step, and again a step, etc.

Thus one may say that the triadic tone roles: prime, third, and fifth behave analogously to the Solmization syllables (see the background image of the lower video):

  • The prime is always preceded by a fourth from below and followed by two thirds.

  • The third is always preceded by a third from below and followed by a third and a fourth.

  • The fifths is always preceded by a third from below and followed by a fourth and a third.

Each voice cycles through the syllables do - re - mi - fa - so - la - ti three times and cycles through the tone roles prime - third - fifth seven times. The entire cycle completes after 21 tones in each voice.

In addition to just playing the "Voice-Go-Round" you may pick one of the three voices and sing the tone roles, while playing the other two voices on the instrument.

NB: The above Movie was made with an earlier version of the App.