Play Upper Structures Over a Minor ii-V-I? Move One NoteHow Do You
Take a Gm7♭5 voicing and remove the root. What's left is B♭, D♭, F — a B♭ minor triad. Now let the F fall a half step to E natural and that same shape becomes B♭ diminished, which is the sound of C7. You have just played a minor ii-V with two triads and one moving voice. Junewon Choi teaches this as the working core of upper structures at VoiceLid Jazz Guitar, and it's why his online jazz guitar lessons treat the 3rd, not the root, as the place you start looking at a chord.
The reason this works is historical as much as theoretical. Charlie Parker took the seventh chord jazz had just adopted, stacked a tension on top of it, and dropped the root out of his own line. That's the origin of the upper structure — not a chord-substitution trick, but a redistribution of who plays what.
Why does removing the root change everything?
Root motion is the bass player's information. For the soloist and the comping instrument, the useful movement lives above it: the 3rd moving to the next 7th, the 7th moving to the next 3rd, and tensions layered over that. Once you stop tracking roots, the harmony stops looking like a series of vertical stacks and starts looking horizontal.
Root: handled by the bass. Doubling it adds nothing.
3rd and 7th: the guide tones. They define the chord.
Tension above: the color Parker added — and it does not have to sit an octave up. A 9th played low, next to the 3rd, is still a tension if it functions as one.
What's left in your hand: two fingers for guide tones, the rest free.
This is also why pianists of that era — Bud Powell, Thelonious Monk, Red Garland, Wynton Kelly — went to shell voicings. They cleared the middle of the chord so the horn player's upper structures had room to speak.
Is an upper structure just a chord substitution?
No, and the difference matters. Substitution thinking keeps you inside the diatonic system: you swap one diatonic chord for another that shares notes. Upper structure thinking is about superimposition — the rhythm section plays the written change while you play a different harmony above it, moving chromatically through notes that were never in the key.
That chromatic freedom is the whole point. If you stay inside substitution logic, you never get the passing tones that make a bebop line sound like bebop. The Bridge Series maps how upper structure triads attach to chord function rather than to chord names, which is the distinction that makes superimposition safe instead of random.
How do I actually play the Gm7♭5 – C7 – Fm?
Work it in one position first, on the string set where it lies easily.
Play Gm7♭5 with the root. Then play it without — you're holding B♭ minor.
Move F down a half step to E natural. That's B♭ diminished, and it's your C7 sound (with the ♭9 and ♭13 already built in).
Resolve to Fm — minor 6 or minor 7, either works.
Now find the same two triads somewhere else on the neck. And again. They live in several places.
Play the whole thing as a line instead of as chords. That's a Wes line.
Notice what did not happen: you never spelled out a Gm7♭5 arpeggio, never thought about a locrian scale, never counted degrees. One note moved. The change announced itself.
For the major-key version of exactly this relationship, see Why Can You Play the Same Notes Over Cm7 and E♭Maj7?.
What's the trap advanced players fall into here?
Thinking vertically. Once someone learns upper structures, the instinct is to look at each chord and stack a triad on it, chord by chord, as if solving a series of small puzzles. That produces correct notes and dead music.
The point of the upper structure is the opposite: because your hand is already sitting on the right shape, you mostly stay put. You move the single voice that needs to move, and the progression plays itself. Everything else stays. That's what makes the approach linear rather than vertical — and it's why the note you moved to is so often the melody note of the tune.
For more on stacking triads over changes deliberately, Upper Structure Triads and Superimposition goes further into the mechanics.
Where does the Wes line fit?
The last thing you played in that exercise — the line that came out of the two triads — is the Wes line shape. That's not a coincidence. Wes Montgomery's vocabulary is upper-structure logic played horizontally, which is why it transfers across minor ii-V-I, major ii-V-I, and key-center playing without needing new material each time.
If you want that fretboard logic laid out in full — how the line is built, where it sits, and how it moves — Wes' Insight breaks down exactly how Wes read the neck.
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