From 50 Essential Guitar Lessons
Although you could combine almost any two scales into a hybrid, the first one we will focus on involves notes from the A minor pentatonic (A–C– D–E–G) and A major pentatonic (A–B–C#–E–F#) scales. Fig. 1 shows you a fingering for each of these scales. The third fingering is the scale that results when you combine them—the scale we will call the A minor/major pentatonic hybrid (A–B–C–C#–D–E–F#–G). The notes in boxes in this fingering represent the notes of an A7 chord (A–C#–E–G); soloists tend to emphasize these when they use this kind of scale. The rationale behind this hybrid is simple: when players solo over a dominant seventh chord, they generally create phrases with the minor pentatonic or the major pentatonic. So it makes sense to create a hybrid that is based on these two scales.
The lick in Fig. 2 uses the hybrid scale fingering.
Fig. 2 - Download Example Audio
The hybrid scale in Fig. 3 combines the A major pentatonic scale and the A blues scale (A–C–D–E%–E–G), also commonly used over an A7 chord.
When combined, they form the A blues/major pentatonic hybrid scale (A–B–C–C#–D–Eb–E–F#–G). Because this new scale has nine notes, it can seem a bit unwieldy. But remember, when you solo with this (or any scale for that matter), there is no need to use all the notes. Again, you can emphasize the notes in an A7 chord (the notes in boxes). Examine the licks in Figs. 2 and 4 to see how they favor these notes—and notice that neither lick uses all the notes in the scale.
Fig. 4 - Download Example Audio