The Dorian Scale This is simply two dorian shapes stacked on top of each other, a whole tone apart Here is the building block of this scale – the Dorian tetra chord. Stack two of these and you have the Dorian scale. The Phrygian Mode using Tetra Chords If you want to create a Phrygian scale, then stack two Phrygian tetra chords on top of each other, a full tone apart. Here is the G Phrygian Scale up the Neck Notice how the G in red on the D string plays a dual role. It is the fourth note of the second Phrygian tetra chord, and the first note of the third phrygian tetra chord on that D string. Also, notice how we ran out of strings, so the final phrygian tetrachord ion the G string, starting on D note, is only 3 of the four notes in the phrygian tetra chord. The G Aeolian Scale The G Aeolian is simply the G dorian tetra with a phrygian tetra stacked on top, one whole step apart. Here is what a dorian shape looks like: Stack a phrygian shape on that dorian shape, and you have the Aeolian scale. And if that doesn’t excite you, then look at how you can stack several of these to go way up the neck! And do this knowing only one, four-note pattern. Notice how the G in red plays a dual role. It is the last note of the stacked phrygian shape, and the first note of the dorian shape. So it has a dual role. Also notice how the last tetra chord, which starts on D on the G-string, is only a partial tetrachord, containing only three notes. This is because we ran out of strings! [Wouldn’t it be cool to put a C string on top so we can keep the pattern going? But then all the guitarists would be telling us to get a guitar… because they lack vision?] .