What this section is
documented concepts, original exercises
This lab studies a documented harmonic idea: dividing the octave into three equal major thirds and treating each resulting note as a temporary tonal centre, each approached by its own dominant. The harmonic system is popularly called “Coltrane changes” after its association with John Coltrane’s late-1950s writing. Attribution of who first used which device, and how deliberately, is historically debated — treat the naming as convention rather than settled fact. No transcriptions or copyrighted material are reproduced here; every exercise below is generated from the interval structure itself.
The cycle
Cmaj7→B7→Emaj7→E♭7→A♭maj7→G7→Cmaj7
Exercise: the cell through all three centres
1-2-3-5 on each tonic
C centre
ABC♯E
approach dominant guide tonesG♯D
E centre
D♭E♭FA♭
approach dominant guide tonesCG♭
A♭ centre
FGAC
approach dominant guide tonesEB♭
Why am I practising this?expand
- What it teaches
- Rapid identification of a new tonal centre when the harmony moves by major third rather than by fourth.
- Problem it solves
- Cadences that move in equal major thirds give the ear no diatonic ladder to climb; you must know each centre outright.
- Physical skill
- Three widely spaced keys in quick succession, which exposes any key you have not practised evenly.
- Theory reinforced
- Twelve semitones divided by four gives three centres. Each is preceded by its own dominant, so each resolution is conventional even though the overall motion is symmetrical.
- Improvisation
- Short, chord-tone-based cells survive fast harmonic motion; long scalar lines do not.
- Ear training
- Sing the target root before the dominant resolves. That anticipation is the whole skill.
- Common mistakes
- Trying to play continuous eighth-note lines through the changes before the three centres are secure; ignoring the dominants and only arpeggiating the tonics.
- Recommended tempo
- Very slow — one chord per bar at 60 BPM — until the centres are automatic. Speed is meaningless here without accuracy.
- Increasing difficulty
- Start the cycle from all twelve notes, then descend in major thirds, then approach each chord tone with an enclosure.
- Mastered when
- You can name and play the next tonal centre before the dominant sounds, from any of the twelve starting notes.
How to practise it
- 01Play only the three tonic roots, in time, until the major-third distance is in your ear.
- 02Add the maj7 arpeggio on each centre.
- 03Insert the approach dominant before each centre and play only its guide tones.
- 04Apply the melodic cell to each centre without stopping.
- 05Change the starting note and repeat; there are twelve starting points.