Bi-Triadic Hexatonic Scales

Take two triads, any two triads. Preferably, two triads that don’t have any notes in common. When you arrange them so that they form a scale, that scale is a Bi Triadic Hexatonic Scale.  As an example, let’s take A Minor and G Major.

First, in Example 1, I write the triads out as chords. Then, in Example 2, I write the notes out as arpeggios. Next, in Example 3, I arrange them in a way that combines them to form a scale with 6 tones, a “hexatonic” scale.

Am G Bi Triadic Hexatonic Construction

I especially like this one, because it’s a minor scale with no sixth degree, which makes it ultra useful, since you can use it in place of natural minor or Dorian.

Let’s try an A minor triad with a G minor triad. When combined into a scale, it yields a minor pentatonic scale with the addition of the b2. See examples 3 – 6.

1 b2 b3 4 5 b7 (Pentatonic With b2)
Building a Bi Triadic Hexatonic Scale with an Am triad and a Gm triad

So far, these have been fairly “normal” sounding: kind of diatonic or modal, not really that exotic or “outside” sounding. Let’s try one that starts to move in the “outside” direction. Examples 7-9 take the A Minor triad and combine it with the Eb Major triad.

1 b2 b3 #4 5 b7
How to Construct a Hexatonic scale from an Am and an Eb Triad

So far, we’ve just been building Minor Hexatonics, so let’s see what we get when we start with an A Major Triad.

In examples 10-12, we start by combining an A Major triad with a G# Minor triad. When it all shakes out, we get a pretty “inside” sounding ALMOST Lydian scale. In fact, it’s a Lydian scale without a 6th degree: 1 2 3 #4 5 7.

1 2 3 #4 5 7
Constructing a scale from an A triad and a G#m triad

We can also combine triads to get another kind of altered dominant sound. In this case, let’s look at Examples 13-16, which use the  A major and G minor triads.  It becomes a kind of “Phyrigian Dominant” or “Mixolydian b9” without the 6th degree, so: 1 b2 3 4 5 b7.

1 b2 3 4 5 b7
Constructing a Bi Triadic Hexatonic Scale from A Major and G minor

The triads from which we build these hexatonic scales don’t have to be limited to major or minor, we can also use augmented, diminished and sus4 triads.

In examples 14 – 16, we combine A Major and the G Augmented Triads. This particular combination yields a “Not Quite Lydian Dominant” scale. Or a Lydian Dominant without the 6th degree: 1 2 3 #4 5 b7.

A Major and G Aug Bi Triadic Hexatonic Scale
Bi Triadic Hexatonic Scale From A Major and G Aug

Now that you’ve got the gist, you can try building your own. Some to try: A major combined with G# Diminshed, Am combined with Bb Sus4, A major with C minor.  Let me know through the comments what you come up with.

Have fun.