How Do You Connect the Changes on a Blues? Wes Montgomery’s Diagonal Line in The Thumb
You connect the changes on a blues by letting your line travel with the harmony — moving diagonally across the fretboard as the chords move — instead of parking in one position and hoping the changes come to you. Wes Montgomery's own blues The Thumb is the masterclass: a riff-and-groove tune in G, recorded on Tequila (1966), whose entire engine is that diagonal motion. At VoiceLid Jazz Guitar, Berklee-trained guitarist Junewon Choi teaches online jazz guitar lessons around this exact skill, because it's the difference between soloing on a blues and merely soloing during one.
What does "parking in a box" actually cost you?
It costs you the story. When your hand lives in one position, every chord change has to be absorbed by the same handful of shapes, so your line flattens the harmony instead of expressing it — the IV chord arrives and nothing in your playing announces it. Listeners can't name what's missing, but they feel it: the solo circles rather than travels. A blues has a small, beautiful plot — home, away, the turnaround pulling you back — and a parked line tells none of it. The fix isn't more vocabulary in the same spot. It's mobility: a line that physically moves when the harmony moves.
Why is The Thumb such a clear lesson in this?
Because the tune itself is built on groove and riff — the kind of setting where most players default to one box — and Wes instead drives the whole form with lines that cut across the neck. The melody has a question-and-answer shape, the groove locks you to the time, and the diagonal movement carries you through the changes so completely that the tune feels finished even with nothing behind it. That self-sufficiency is the point: a blues line built this way needs no safety net, because the harmony is inside the line. It's the same fretboard logic we traced in How Wes Montgomery Actually Read the Fretboard.
What is diagonal movement, concretely?
It's a way of building lines where position changes happen inside the phrase, along the length of the neck, rather than between phrases:
The line follows the voice leading — the note that must move when the chord changes decides where your hand goes next.
Position shifts land on meaningful notes — you arrive somewhere because the harmony arrives there.
One phrase can cross four or five frets diagonally — connecting regions most players treat as separate zones.
The groove stays anchored — mobility in space, stability in time.
This is the Wes Line and Django Line logic that runs through the whole FDA system; the Fundamental 1: Wes Diagonal System course builds it from the ground up. And for how these lines behave at speed on a bebop blues, see Playing Wes Line and Django Line Over Fast 2-5s: Blues for Alice.
How do you practice connecting the changes?
Take one chorus of a blues in G and refuse to let any phrase end in the position it started. Play the head, find the two or three notes that change between each chord, and build short lines that walk to those notes along the neck instead of across it. Slow is fine — the win is hearing your line announce the IV chord's arrival for the first time. Do this for a week and the blues stops being a grid you survive and becomes a road your hand actually drives.
Where can you study Wes's line note for note?
In Wes' Blues Insight — The Thumb, Junewon opens a full chorus of the tune: complete chord-melody arrangement, solo transcription, and a 10–15 minute breakdown of exactly how the diagonal phrasing and voice-leading connect the changes — full PDF with notation and TAB. It's the Line chapter of the three-tune series through Wes's own blues. If Cariba showed the sound, The Thumb shows how the sound moves.
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