The Common Minor Pentatonic b6 & Scale Spectra
This interesting but little-known scale cropped up in the context of some exotic scale work this week. It's easy to learn, has an unusual but very usable sound and can help with learning several larger scale structures.
Learning the Shapes
The scale is just a Common Major Pentatonic (1 2 3 5 6) with the 6 flattened to give 1 2 3 5 b6. Hence its fingerings are all identical to those of the Common Major with just with sixth moved down one fret, although technical considerations might make you want to move that note to a neighbouring string in some cases.
Thinking of it another way it's just a major triad arpeggio with the 2 (=9) and the b6 (=#5) added. I mention that the b6 is the same as the #5 because it might help to think of it as the "union" of the major and augmented triads overlaid on top of each other. This seems to work quite well for me; then the only task is to add the 2.
As with any scale, once you have a general idea how to play it it's worth working with it for a while, finding the technical challenges and getting the sound into your ear.
Heptatonics
Something you probably learned early on is that the Major Scale modes can be related to Common Pentatonic modes with two added notes; this may even have been the way you first learned them (as it was for me). This is a trick we can use with more advanced material as well. All the scales in this section are given full fingering diagrams in Scale and Arpeggio Resources.
The following are all the "obvious" heptatonic scales that consist of this pentatonic plus the 4 and 7, however altered:
| 1 2 3 4 5 b6 7 | Harmonic Major |
| 1 2 3 4 5 b6 b7 | Mixolydian b6 (mode of Melodic Minor) |
| 1 2 3 4 5 b6 bb7 | Mararanjani |
| 1 2 3 #4 5 b6 7 | Latangi |
| 1 2 3 #4 5 b6 b7 | Rishabhapriya (mode of Neapolitan) |
| 1 2 3 #4 5 b6 bb7 | Kantamani (mode of Enigmatic) |
Most of these are very rare in Western music. Things get even more exotic if we add the two notes after the b6:
| 1 2 3 5 b6 b7 7 | Semidominant Augmented (mode of Jyoti Swarupini) |
| 1 2 3 5 b6 6 7 | Augmented ##11 (mode of Varunapriya) |
| 1 2 3 5 b6 6 b7 | Mixolydian ##4 #5 (mode of Rupavati) |
or add either the b2 or #2 plus another note:
| 1 b2 2 3 4 5 b6 | 1maj + b2maj + 2 |
| 1 b2 2 3 #4 5 b6 | Super Locrian bb3 bb6 bbb7 (mode of Jalarnavam) |
| 1 b2 2 3 5 b6 bb7 | Kanakangi b4 (mode of Chalnata) |
| 1 b2 2 3 5 b6 b7 | Ratnangi b4 (mode of Suvarnangi) |
| 1 b2 2 3 5 b6 7 | Super Locrian bb3 nat5 nat7 (mode of Divyamani) |
| 1 2 #2 3 4 5 b6 | Eurean Mode II |
| 1 2 #2 3 #4 5 b6 | 1maj + b2maj + 6dim |
| 1 2 #2 3 5 b6 bb7 | Jhankaradhvani b4 scale (mode of Kanakangi) |
| 1 2 #2 3 5 b6 b7 | Aeolian b4 (mode of Ionian b2) |
| 1 2 #2 3 5 b6 7 | Harmonic Minor b4 (mode of Dhatuvardani) |
There are more possibilities if we allow more consecutive semitones, but this seems like quite enough to be going along with. All of these scales can be learned by adding just two notes to the "skeleton" of the Common Pentatonic b6. It would be an interesting theoretical project to do a similar calculation for every pentatonic, thus seeing every heptatonic as having a "spectral decomposition" into several overlapping pentatonics and grouping together heptatonics that share the same pentatonic kernel.
I'll have more to reveal about this "spectrum" idea soon as I'm working up a book-length set of spectra and I'll be using this one as a handy test case.
