Scale Geometry: Two-string Horizontal Major Scales Shapes
Once major scale shapes are mastered in position, many guitar students come to the erroneous conclusion that they have mastered the diatonic scale. Nothing could be further from the truth. There exist an endless manner in which scales can be approached and expressed. One that is particularly helpful to beginning and intermediate guitarists is that of scale geometry. So far we have learned our scales vertically, meaning the hand does not shift positions once the availability of digits has been exhausted, but rather shifts to the next string. A horizontal approach shifts to the next position once the digits have been exhausted, while remaining on a set amount of strings.
While this could be applied to one string, such an application would be tedious and limiting. In applying it to two strings, we increase our access to pitches in a given position while still maintaining availability of some of the melodic benefits of shifting positions. Obviously we cannot get all seven notes in the scale using the simplicity of a three-note per string approach, so to maintain that simplicity while shifting positions, we restart the sequence of six-notes again after shifting. This creates a natural sequence.
In C Major, it would look like this:
Since this creates a sequence, we can play each two-string cell descending while ascending the scale to create another interesting sequence.
We can also experiment with alternating between playing once cell ascending and the next descending, or vice versa.
Since A minor is the relative minor of C major, the figures above are also the horizontal two-string scales for A minor. To create two-string scales from CAGED shapes, simply look along any two strings. Play the first six notes on that string set, even if means combining two positions, and preceded from there.
You will notice that this approach creates five string sets. This pairs perfectly with the twelve-minute exercise. Go to my Youtube channel and use the major or minor scale backing tracks to improvise on each string set for two minutes, followed by another two minutes of free improvisation in the given key.