0005. Types of chords vs types of pentatonics

Everybody knows that minor pentatonic reflects features of most minor chords, scales or modes (must be with b7 and 4), because of it`s evident structure: 1 b3 4 5 b7.

Measured from b3 (considered as new root), the same tones give structure of major pentatonic: b3 4 5 b7 1 = 1 2 3 5 6. It covers qualities of many major chords, scales or modes.

Following explanation is written with particular letters, to emphasize close relation between pairs of relative pentatonics, which in fact are the same thing.

  1. Minor pentatonic equaly reflects features of m7, maj7 and similar chords:

Am7 fits Cmaj7 as 1 b3 4 5 b7 (A C D E G) fits 1 2 3 5 6 (C D E G A)

Let`s discuss remaining asymmetric seventh chord types: dom7, 7alt, m7b5, m maj7, maj7#5.

  1. Features of dominant seventh chords are well reflected by minor pentatonic with major third (M3). Measured from 3rd degree it also perfectly fits with 7alt (enharmonically = m7b5).

A7 fits C#7alt (= C#m7b5) as 1 3 4 5 b7 (A C# D E G) fits 1 b2 #2(b3) b5 #5(b6) (C# D E G A)

  1. m maj7 features are reflected by minor pentatonic with major seventh (M7). Measured from b3rd degree it also covers maj7#5.

Am maj7 fits Cmaj7#5 as 1 b3 4 5 7 (A C D E G#) fits 1 2 3 #5 6 (A C D E G#)

Newly introduced types of pentatonic contain not only plenty of missing m2, M7 and tritone intervals, but also all four possible kinds of triad: major, minor, diminished and augmented. I dare to state, that three types of pentatonics, shown above, are various and versatile enough to act properly in whole range of musical situations.

That also could be proved by mathematical research, which shows us where pentatonics could be used as superimpositions (five-voiced chords).

pentatonics as superimpositions


0004. Density of vertical texture

Density of chosen harmonic devices (quantity of degrees within) affects few crucial parameters of music: construction of arpeggio based melodic phrases, mix of prevailing intervals and force of functional gravity.

Triads have thinnest texture; prevailing intervals are thirds, fourths and their inversions. Functional gravity is evident (heavily determined by Western cultural environment).

In seventh chords we observe denser texture and greater variety of intervals: seconds and sevenths become common, tritones are much more frequent. Functional gravity is the same, excepting dominant seventh chords – those pull even stronger.

Pentatonics also could be considered as vertical formations, with very dense texture. In such conditions fourths, seconds and their inversions start prevail. Functional gravity becomes weak. Looks like the vertical and horizontal of music got really close to each other. Some modes have no more than five harmonically stable tones (phrygian, for instance), all remaining act like passing or chromatic.

Next list shows how superimpositions could be categorized by density of texture: into triads, seventh chords and pentatonics. Pentatonics are marked in bold font; some of them are not common minor/major type and would be explained in further posts.

superimpositions as triads, 7th chords and pentatonics

Pentatonic is powerful but yet underestimated harmonic device. I think it is because of limited intervalic structure of minor/major pentatonic (which lack some of characteristic intervals: m2, M7, tritone). Musicians are trying to alter pentatonics to fit whole range of musical structures, but they often fail to discover fundamental unifying principle. Hope I found simple and sufficient method how to overcome intervalic limitations of pentatonics and control them vertically. Great deal of upcoming materials would be entirely dedicated to this subject.