Module 21 — Reharmonization: Changing the Chords Without Losing the Song
This is where a lot of the material from Modules 5–20 comes together.
The big idea is:
Reharmonization means changing the harmonic interpretation of a melody while preserving enough of the melody, phrase structure, and tonal logic that the result still feels intentional.
The goal is not:
“How many fancy chords can I insert?”
The goal is:
“Can I make the same melody feel more tender, darker, jazzier, more dramatic, more modern, or more surprising?”
21.1Start with a plain progressionWe’ll use a simple C-major framework:21.2Rule 1: preserve the melodyBefore replacing a chord, ask:21.3Rule 2: preserve the phraseA cadence is not just a chord.21.4Functional substitutionChords within the same functional family can often substitute for each other.21.5Tonic substitution: C ↔ AmSuppose melody note is E.21.6Tonic substitution: C ↔ EmIf melody note is G or E:21.7Predominant substitution: F ↔ DmF:21.8Dominant substitution: G7 ↔ B°G7:21.9First reharmonization levelOriginal:21.10Secondary dominantsNow make destinations stronger.21.11The hidden voice-leading linesThis reharmonization works partly because of:21.12Secondary dominant as reharmonization testSuppose melody note over Am is A.21.13ii–V insertionWant to approach a destination more elegantly?21.14ii–V into GDestination G:21.15Minor ii–V into DmDestination Dm:21.16Reharmonization by back-cyclingSuppose destination is C.21.17Build tension by lengthening the routeCompare:21.18More chords do not automatically mean betterIf the melody is slow and intimate, the simple version may be stronger.21.19Passing diminished chordsOriginal:21.20Another passing diminishedOriginal:21.21Diminished versus secondary dominantTo reach Dm, compare:21.22Borrowed chordsOriginal:21.23Borrowed ♭VIInstead of going directly to G7:21.24Borrowed ♭VIITry:21.25Reharmonization by bass-line designThis is one of the most powerful techniques.21.26Extend the descending lineBass:21.27Inner-line reharmonizationYou can do the same in an inner voice.21.28Melody-driven reharmonizationSuppose melody note is A.21.29One melody note, several moodsHold melody:21.30Held note CTry C over:21.31Repeated melody notes invite harmonic motionSuppose melody repeats G for four bars.21.32Static harmony versus moving harmonyTwo extremes:21.33Reharmonization by extension onlyYou don't always need to change chord roots.21.34Reharmonization by inversion onlyOriginal:21.35Reharmonization by chord qualitySometimes change major to minor or vice versa.21.36Common-tone reharmonizationChoose a new chord because it shares melody or inner notes.21.37Chromatic mediants as color reharmonizationTake:21.38Reharmonization and melody tensionSuppose melody is G.21.39The consonance ladderWhen choosing a chord under a melody note, think roughly:21.40Reharmonize backward from the destinationSuppose melody phrase must end on Cmaj7.21.41Reharmonize from phrase architectureSuppose eight bars:21.42Don't use your strongest cadence too earlyIf every two bars ends:21.43Deceptive reharmonizationExpected:21.44Extend a cadenceBasic:21.45Tritone substitution previewHere is an important jazz reharmonization device we'll study more fully in Module 22.21.46Hear G7 → C versus D♭7 → CPlay:21.47A chromatic ii–V possibilityInstead of:21.48Reharmonization by pedal pointKeep bass C.21.49Dominant pedalKeep G in bass:21.50Reharmonization by suspended harmonyInstead of:21.51Same melody, three reharmonization levelsSuppose a simple phrase fits:21.52A reharmonization should have a reasonGood reasons include:21.53Reharmonize repeated sections differentlyIf a melody repeats:21.54Example form strategySuppose melody has A-A-B-A form.21.55Reharmonization can simplify tooImportant:21.56Melody can remain while bass changes radicallySuppose melody note is E.21.57Bass-note-over-melody exerciseHold RH E.21.58Reharmonization workflowFor a real melody:21.59The “remove it tomorrow” testWhen you find a clever reharmonization, record it.21.60Your reharmonization toolbox so farYou now have:21.61A full exampleStart:21.62Now create an inner voiceIn the progression above, deliberately hear:•Homework for Module 21Start:•Module 21 mini-test1. What is reharmonization?