sition? Playing Your Own Changes Over the Band’sWhat Is Superimpo
Superimposition means exactly what it sounds like: the rhythm section states the tune's bass notes and chord sounds, and you play a different set of changes on top of them. It is one of the most advanced concepts in jazz soloing — and one of the most misunderstood, because it is not a license to play anything. At VoiceLid Jazz Guitar, Junewon Choi teaches superimposition in his online jazz guitar lessons as the final floor of a building whose foundation is voice leading: you earn the right to play your own changes by first knowing precisely how the written ones connect. Here's how the mechanism actually works, using All the Things You Are.
What does superimposition actually mean?
The band plays Fm7–Bbm7–Eb7–AbMaj7. You, on top, might play AbMaj7 over the Fm7 (its rootless upper structure), DbMaj7 over the Bbm7, then CMaj7 over the Eb7 — a chord that isn't in the chart at all. Your line now describes a harmony floating above the stated one. Peter Bernstein's standard for this is unforgiving: when you play a note, you should know exactly what sound it creates against what everyone else is playing. Not as arithmetic in your head — as a sound your ear already owns. That's the difference between superimposition and noise.
Why does the half-step slide keep showing up?
Look again at that move: DbMaj7 (over the ii) sliding to CMaj7 (over the V) is chromatic approach applied to whole upper structures — the same half-step logic bebop uses on single notes, scaled up to triads and 7th chords. The classic direction is approaching the I: AbMaj7's upper structure is C minor, so over the Eb7 you can play Db minor — a half step above the target — and slide down into it. That Dbm-over-Eb7 sound has a technical name in Junewon's Block Buster curriculum (the tr4b9 sound), but the concept needs no math:
Find the upper structure of the chord you're going to
Play it a half step above, over the dominant
Resolve down by half step, every voice at once
Do it over a full ii-V-I in Ab and you get DbMaj7 → Dbm → Cm: one shape, sliding home. The full shell-voicing-to-upper-structure map behind this lives in the Bridge Series, and the archive dives deeper in upper structure triads and superimposition.
Is this how you get the altered sound without the altered scale?
Yes — and it's simpler than the scale-book version. The common advice for altered dominants is "play melodic minor a half step up." Junewon simplifies further: play minor a half step up. One minor shape, one concept, transposable everywhere — over major chords, minor chords, and dominants alike. The guitar's great gift is that identical shapes carry identical concepts to any location; the work is not memorizing seven-note scales but tuning your ear to where each shape wants to resolve. For the fuller story, see getting the altered sound with no scale.
Is the tritone sub really a "substitute"?
Wrong question, says Junewon. Nothing substitutes for anything — what matters is the target. A dominant's job is to make its destination sound inevitable; any device that sets up the target as a target is fair game. That reframing also explains passing harmony everywhere in the repertoire: in There Will Never Be Another You, when Cm7 moves to Bbm7, virtually every experienced player inserts the chromatic Bm7 between them — a passing chord written in nobody's chart, demanded by everybody's ear.
How do you start practicing superimposition?
Backwards from the target. Pick one ii-V-I, find the I chord's upper structure, approach it from a half step above, and listen until the resolution feels like gravity. Then steal from the masters who did this on the instrument itself — Wes' Insight breaks down how Wes Montgomery's lines carry exactly these upper-structure moves inside seemingly simple phrases.
About the Author
Junewon Choi is a Berklee-trained jazz guitarist and the founder of VoiceLid Jazz Guitar, an online education platform teaching jazz harmony and improvisation through the Functional Diagonal Approach (FDA) — a chord-first method built on voice-leading rather than scale boxes.
Wes' Insight — Wes Montgomery's fretboard logic, in lesson form
Fundamental 1: Wes Diagonal System — the FDA from the ground up