Introduction: The C2552 Pentatonic Parallel Scales provide an alternative set of notes that can be used to compose melodies (note sequences), chords (sets of simultaneous notes), and cadences (sequences of chords) for compositions expressed within an overall tonal feel. The use of 5-note instead of 7-note scales can result in pleasing new compositions especially when adding techniques of using parallel scales together.
Basics: The C2552 Pentatonic Parallel Scales consist of two 5-note scales each starting on C. The minor scale starts on C and goes next to D (2 tone interval). The major scale starts on C and goes next to F (5 tone interval). Both scales continue with G. They differ then repeat beginning at octave C’. Here are the C2552 Pentatonic Parallel Scales:
|C25 Pentatonic Minor||C D G Ab Bb|
|C52 Pentatonic Major||C F G A B|
Theory: C25 and C52 are parallel minor and major pentatonic 5-note scales. Written in tone (pitch) notation they are C D G Ab Bb and C F G A B. Written in interval (pitch difference) notation they are C25122 and C52221. C25 is minor because its first characteristic interval is smaller (2). C52 is major because its first characteristic interval is larger (5). C is the root tone of both scales, D and F are the modes, G is neutral, and Ab and B are active. Ab is active because it immediately follows neutral G. B is active because it immediately precedes root C.
Comparison: C25122 and C52221 are analogous to the C minor and C major parallel minor and major diatonic 7-note scales. Written in interval notation those scales are C2122122 and C2212221. That they are minor and major can be seen by reexpressing them as 5-note scales C34122 and C43221. For those scales C is the root, Eb and E are the modes, G is neutral, and Ab and B are active.
Mirror Scales: C25122 and C52221 are mirror reflections of each other as can be seen by reexpressing them as C25122 <=> C22152. Continuing the comparison, C minor and C major are also mirror reflections (C34122 <=> C22143).
Negative Harmony: Mirror reflection is also called Negative Harmony. A note or chord selected from a minor scale can be reflected to a parallel note or chord in the parallel major scale.
Here are the C25122 and C52221 5-note scales shown using Negative Harmony where C reflects to G and back, D to F, and B to Ab. (Bb and A also reflect though they have no labeled function.)
|B active||D mode|
|Ab active||F mode|
Continuing the comparison, here are the C minor and C major 7-note scales shown using Negative Harmony where C reflects to G and back, Eb to E, and B to Ab. (D to F and Bb to A also reflect though they have no labeled function.)
Tonality/Borrowing: A note, note progression, chord, or chord progression can be written using a) only the minor scale, b) only the major scale, or c) both. Using chords from both scales together is called borrowing. A composition using both minor and major scales and their chords can be said to be written using their full tonality.
Tonality Benefits: Using minor and major scales together gives additional note (melody) and chord (cadence) options for writing songs while staying within an overall tonal feel. C25122 and C52221 have 5 notes each—together they have a total of 8. C minor and C major have 7 notes each—together they have 10. C25122 and C52221 have 5 trichords each—together they have a total of 24 (see table below).
Pentatonic Parallel Scale Motivation: The original motivation was to have a set of notes with which to compose tone sestets where, in each composition, six (6) musical expressions would be separated by five (5) musical spaces. This motivation has since been extended.
Chords: The use of trichords can be extended to include 2-tone intervals:
|Scale||Scale Tones||Chords||Chord Tones|
|C25122||C D G Ab Bb||C25|
|C D G|
G Bb D
G Bb C
Ab Bb D
Ab C D
|C52221||C F G A B||C52|
|C F G|
F A C
G A C
F A B
F G B
|Combined||C D F G Ab A Bb B||C23|
|C D F|
D F G
D F A
Bb D F
D G A
Bb C F
A C D
F G Bb
D F Ab
B D F
A B D
F Ab Bb
Ab B D
F Ab B
Chord Functions: The use of trichord functions can be extended to include ambivalence:
|Note Type||Chord Type||Energy|
|Root and/or Mode||Tonic||Rest|
|No Mode + No Active||Subdominant||Float|
|No Mode + Active||Dominant||Urge|
|Root and/or Mode + Active||Ambivalent||Clash|
Cadences: The use of cadences (chord sequences) can be extended to include ambivalence, statence, and driftance:
|Chord Sequence||Cadence Type||Movement Energy|
Additional Scales: Here are eight identified-to-date penatonic parallel scale mirror pairs and their tonalities:
|Tonality||Scales||Number of Tones||Number of Trichords|
Transposing: The C2552 Pentatonic Parallel Scale Tones and Chords can be moved up or down in pitch to start on / be associated with a different root tone.
Example Composition: Morning Aire F2552 – Figures & Cadences & Dynamics
Fine Print: This post summarizes work and studies by James G Neville / Sitearm Madonna over the last 19 months. Adaptations and extensions of traditional music theory topics and notation as expressed in this post and associated scores are mine. Comments, questions, corrections are welcome.