Harmonic Sequence · Jazz Wiki

A harmonic sequence takes a short chord pattern and repeats it starting from a different root, over and over, so the ear locks onto the shape and rides it somewhere new. It is the harmonic version of a rhyme scheme: once you hear the pattern once, you expect it again, and that expectation is what gives the progression its forward pull. Jazz leans on sequences constantly, because they turn a handful of chords into a whole tune’s worth of momentum and travel through key centers.

What Makes It a Sequence, Not Just a Progression

A single ii-V-I is just a progression. Stack several of them, each starting on a new root by a consistent interval, and you get a harmonic sequence — a repeated model applied systematically. This is the harmonic cousin of melodic sequence: instead of a melodic cell repeating up or down the scale, an entire chord unit repeats, carrying the root motion pattern with it.

A single ii-V-I in C: Dm7 – G7 – Cmaj7 (a progression)
The same model repeated down by fifths: Dm7–G7–Cmaj7, Gm7–C7–Fmaj7, Cm7–F7–B♭maj7 (a harmonic sequence)

Not every progression that happens to move around the circle of fifths counts. The circle is the map; a harmonic sequence is a specific, repeated route drawn on it.

Descending Fifths: The Sequence Jazz Runs On

Root motion by descending perfect fifths is the strongest pull in tonal music — it’s the same gravity that resolves any single V–I — so chaining that motion across multiple ii-V-I units, a technique called backcycling, produces long stretches of harmony that feel inevitable rather than arbitrary.

Four successive ii-V-I’s descending by fifths, starting in C:

Dm7  - G7  - Cmaj7
Gm7  - C7  - Fmaj7
Cm7  - F7  - Bbmaj7
Fm7  - Bb7 - Ebmaj7

The four ii–V–I units overlap on the circle, so their roots fuse into one unbroken counterclockwise chain of falling fifths (D–G–C–F–B♭–E♭)

Solar compresses this idea into a twelve-bar tune: after opening on its C minor tonic, it walks the ii-V-I model down through F, E♭, and D♭ — Gm7–C7–Fmaj7, then Fm7–B♭7–E♭maj7, then E♭m7–A♭7–D♭maj7 — with each arrival chord turning minor to become the next ii, so the roots trace one unbroken chain of falling fifths (G–C–F–B♭–E♭–A♭–D♭). The harmonic rhythm of Solar is fast enough that the sequence itself becomes the melody’s whole environment — see Harmonic Rhythm for how the pace of chord change shapes a tune’s feel.

The bookends of that chain — the ii-V-I in C and the ii-V-I a fifth lower in E♭ — show the same model transposed intact:

Sequences That Modulate: Thirds Instead of Fifths

Descending-fifths sequences stay diatonic and predictable; sequences built on thirds are how jazz standards travel to genuinely distant keys. All the Things You Are opens with a vi-ii-V-I model in A♭ that unexpectedly cadences a major third away, in C; the second eight bars then restate the entire model a perfect fourth lower, so the same trick lands in E♭ and then G — the sequence itself performs the Modulation, no extra glue chords needed:

Fm7 - Bbm7 - Eb7 - Abmaj7 - Dbmaj7 - Dm7 G7 - Cmaj7   (Ab, veering up a major third to C)
Cm7 - Fm7  - Bb7 - Ebmaj7 - Abmaj7 - Am7 D7 - Gmaj7   (same model a fourth lower, landing in G)

Push the major-third idea to its extreme and you get Coltrane Changes: a sequence of major-seventh chords a major third apart, each one preceded by its own secondary dominant, dividing the octave into three equal parts instead of the usual seven-note circle:

Bmaj7 – D7 – Gmaj7 – B♭7 – E♭maj7 – F♯7 – Bmaj7

That’s the harmonic backbone of Giant Steps, and it’s genuinely a different animal from fifths-based sequences — the ear has to track three unrelated tonal centers instead of one gravity well.

Stacked as pads, the three major-third-related tonic chords and their secondary dominants show the octave splitting into equal thirds (B–G–E♭–B):

What Sequences Ask of the Player

Because a sequence repeats the same shape at a new pitch level, the Voice Leading inside it usually can’t stay perfectly smooth the way a single well-crafted progression can — some voice has to leap to reset the pattern for the next round, and good arrangers pick the leap that’s least audible. It’s also worth being honest that not every fifths-heavy tune is “sequential” in the strict sense: a single turnaround or one ii-V-I borrowed via Tritone Substitution is just a progression, not a sequence, until the model actually repeats.

♫ Listen

John Coltrane — “Giant Steps” (Giant Steps, rec. May 1959, rel. 1960): the definitive major-thirds sequence; track how the tenor line has to leap to catch each new key as B, G, and E♭ major cycle past every two bars.
Miles Davis — “Solar” (Walkin’, rec. April 1954, rel. 1957): a clean descending ii-V-I sequence — follow the bass roots falling in one unbroken chain of fifths through F, E♭, and D♭ before the tune resolves home.
Bill Evans Trio — “All the Things You Are” (At Shelly’s Manne-Hole, rec. May 1963): ballad tempo makes the major-third modulations between key centers easy to hear in the piano voicings.