Rhythm changes · C major
This is the 32-bar AABA rhythm-changes form — here the 8-bar A section and the dominant-cycle bridge — in C, the chords are C△7 – Am7 – Dm7 – G7 – C7 – F△7 – F♯°7 – E7 – A7 – D7. In C the A section walks C△7 – Am7 – Dm7 – G7 twice, then pushes to the IV chord F△7 through C7; the passing F♯°7 lifts the bass from F to G. The bridge is a chain of dominants a fourth apart — E7 → A7 → D7 → G7 — two bars each, landing back on C△7.
The form
A section (8 bars)
Bridge (8 bars)
Generic form in Roman numerals — the harmonic skeleton, not any particular tune. Two chords in a bar are two beats each.
Interactive trainer
Piano · C△7 with Major (Ionian)
Guitar · standard tuning
Piano · Am7 with Dorian
Guitar · standard tuning
Piano · Dm7 with Dorian
Guitar · standard tuning
Piano · G7 with Mixolydian
Guitar · standard tuning
Piano · C7 with Mixolydian
Guitar · standard tuning
Piano · F△7 with Major (Ionian)
Guitar · standard tuning
Piano · F♯°7 with Diminished (whole–half)
Guitar · standard tuning
Piano · E7 with Mixolydian
Guitar · standard tuning
Piano · A7 with Mixolydian
Guitar · standard tuning
Piano · D7 with Mixolydian
Guitar · standard tuning
Click any chord card to see its scale, and tap any key or fret to hear that note. Turn on “+ Arpeggios” or “+ Scales” and the guitar or piano plays the line live over the vamp, lighting each note on the diagram as it sounds. All audio is synthesized in your browser — nothing is recorded or copyrighted.
Your next 10 minutes
At 60 bpm, first find these chord roots: C, A, D, G, C, F, F♯, E, A, D. Then play or sing the root of each sounding chord as you follow the trainer. Keep counting through the whole form. If you lose your place, return to roots before adding notes.
C△7: E and B; Am7: C and G; Dm7: F and C; G7: B and F; C7: E and B♭; F△7: A and E; F♯°7: A and E♭; E7: G♯ and D; A7: C♯ and G; D7: F♯ and C. Choose one voice and move to the nearest third or seventh in the next chord. Use your ear; not every transition is a half step.
Using the chords C△7, Am7, Dm7, G7, C7, F△7, F♯°7, E7, A7, D7, use only chord tones for one chorus. On the next chorus add a single passing note between targets. Repeat one rhythmic idea, then leave a full bar of space.
Listen for this: Resolve into C△7 without rushing. Success means keeping the form and hearing your next target, not reaching the highest tempo.
Understand the sound
Learn the A section and bridge as separate units. The bridge’s dominant cycle has a different harmonic rhythm from the quicker changes in the A section. The trainer displays the A-section and bridge material; learn how these fit into the full AABA form.
| Chord change | One possible line | Movement |
|---|---|---|
| C△7 → Am7 | B → C | Up 1 semitone |
| Am7 → Dm7 | G → F | Down 2 semitones |
| Dm7 → G7 | C → B | Down 1 semitone |
| G7 → C△7 | F → E | Down 1 semitone |
| C△7 → C7 | B → B♭ | Down 1 semitone |
Play the first pitch in each row during its chord, then move to the target as the next chord begins. Choose an octave that allows the indicated movement. Sing the line once before playing it; add the bass roots only after the upper voice feels secure.
Stop playing for one complete cycle while you keep counting. Re-enter on C△7. If you miss the entrance, simplify to roots and work at 60 bpm before adding passing notes.
Reference
| Function | Chord | Chord tones (1–3–5–7) | Chord-scale | Scale notes |
|---|---|---|---|---|
| I△ | C△7 | C – E – G – B | Major (Ionian) | C D E F G A B |
| vi⁷ | Am7 | A – C – E – G | Dorian | A B C D E F♯ G |
| ii⁷ | Dm7 | D – F – A – C | Dorian | D E F G A B C |
| V⁷ | G7 | G – B – D – F | Mixolydian | G A B C D E F |
| I⁷ | C7 | C – E – G – B♭ | Mixolydian | C D E F G A B♭ |
| IV△ | F△7 | F – A – C – E | Major (Ionian) | F G A B♭ C D E |
| ♯iv°⁷ | F♯°7 | F♯ – A – C – E♭ | Diminished (whole–half) | F♯ G♯ A B C D D♯ F |
| III⁷ | E7 | E – G♯ – B – D | Mixolydian | E F♯ G♯ A B C♯ D |
| VI⁷ | A7 | A – C♯ – E – G | Mixolydian | A B C♯ D E F♯ G |
| II⁷ | D7 | D – F♯ – A – C | Mixolydian | D E F♯ G A B C |
| Guide tones | C△7 | Am7 | Dm7 | G7 | C7 | F△7 | F♯°7 | E7 | A7 | D7 |
|---|---|---|---|---|---|---|---|---|---|---|
| 3rd | E | C | F | B | E | A | A | G♯ | C♯ | F♯ |
| 7th | B | G | C | F | B♭ | E | E♭ | D | G | C |
How to practise this
1. Arpeggios in time. Loop the vamp at 70–90 bpm and play C△7, Am7, Dm7, G7, C7, F△7, F♯°7, E7, A7, D7 as 1–3–5–7 quarter notes, one chord per bar. Use the “+ Arpeggios” loop above to hear it played and copy the line.
2. Guide tones. Play only the 3rd and 7th of each chord: E–B → C–G → F–C → B–F → E–B♭ → A–E → A–E♭ → G♯–D → C♯–G → F♯–C. Notice that F, the 7th of G7, moves to E, the 3rd of C△7 — that is the resolution.
3. Chord-scales. Run Major (Ionian) on C△7, Dorian on Am7, Dorian on Dm7, Mixolydian on G7, Mixolydian on C7, Major (Ionian) on F△7, Diminished (whole–half) on F♯°7, Mixolydian on E7, Mixolydian on A7, Mixolydian on D7, then improvise keeping chord tones on beats 1 and 3.
4. Move it. When C is clean, go to F major — a fourth up — and keep going around the circle.
Take it to the bandstand.Practice Radio streams this form and every other progression through all twelve keys, with the chord and scale shown live — plus ear-training and call & response modes.
▶ Open Practice RadioCommon questions
C△7 – Am7 – Dm7 – G7 – C7 – F△7 – F♯°7 – E7 – A7 – D7. The I chord is C△7 (C, E, G, B); The vi chord is Am7 (A, C, E, G); The ii chord is Dm7 (D, F, A, C); The V chord is G7 (G, B, D, F); The I7 chord is C7 (C, E, G, B♭); The IV chord is F△7 (F, A, C, E); The ♯iv° chord is F♯°7 (F♯, A, C, E♭); The III7 chord is E7 (E, G♯, B, D); The VI7 chord is A7 (A, C♯, E, G); The II7 chord is D7 (D, F♯, A, C).
C△7: Major (Ionian) (C D E F G A B). Am7: Dorian (A B C D E F♯ G). Dm7: Dorian (D E F G A B C). G7: Mixolydian (G A B C D E F). C7: Mixolydian (C D E F G A B♭). F△7: Major (Ionian) (F G A B♭ C D E). F♯°7: Diminished (whole–half) (F♯ G♯ A B C D D♯ F). E7: Mixolydian (E F♯ G♯ A B C♯ D). A7: Mixolydian (A B C♯ D E F♯ G). D7: Mixolydian (D E F♯ G A B C).
The thirds and sevenths: E and B over C△7, C and G over Am7, F and C over Dm7, B and F over G7, E and B♭ over C7, A and E over F△7, A and E♭ over F♯°7, G♯ and D over E7, C♯ and G over A7, F♯ and C over D7. Connect each voice to the nearest available third or seventh of the next chord; the distance depends on the progression and voicing.
Loop the vamp at a slow tempo, play each arpeggio 1–3–5–7 in time, then play each chord-scale up and down, then improvise using only chord tones on the strong beats. When it is clean, move to the next key around the circle of fourths.
All twelve keys
Related in C: ii–V–I · turnaround · jazz blues. Read the theory in What is a ii–V–I?, or see the scales on their own pages: C Major, A Dorian, D Dorian, G Mixolydian, C Mixolydian, F Major, F♯ Dim. W–H, E Mixolydian, A Mixolydian, D Mixolydian.