Tenth and final lesson. Until now, we have always given you ready-made chord charts. Today, we reverse: you have a melody, and it is YOU who choose the chords. This is called harmonizing, and it is the culmination of everything we have built together, within tonality, the framework in which we harmonize. No new concept in this lesson: just your entire toolbox, finally used to create.
The Essential in 30 Seconds
Harmonizing is choosing the chords that accompany a melody. In a given tonality, we have a palette of seven chords, called diatonic chords, built on each degree of the scale (in C major: C, D minor, E minor, F, G, A minor and B diminished). To harmonize a melody note, we choose a chord that contains that note: for example, under a C melody note, we can place the C chord (I), F chord (IV) or A minor chord (vi), each giving a different color. The same melody can therefore be harmonized in several ways: it is both mechanics (the chord must contain the note) and a creative choice (the vibe sought), guided by cadences.
1. What is harmonization: from performer to arranger
Until now you executed charts. Harmonizing is creating them: starting from a melody (sung, whistled, played) and deciding which chords carry it. A vocabulary note in passing: choosing the chords is harmonization. Arrangement goes further (who plays what, with what rhythms, what texture), but harmonization is its heart. Today, you gain the heart.
And the method combines exactly two skills you already have: the mechanical (which chords contain the melody note) and the artistic (what harmonic movement you want to tell). The first is calculated; the second is chosen. This mix makes harmonization a creative act and not a math exercise.
2. The 7 diatonic chords: your chord palette
Your palette, you do not have to invent it: it comes straight from the scale. Build major and minor triads on each of the degrees of the major scale, staying within the scale: here are your 7 diatonic chords. And the order of colors is always the same, whatever the major tonality:
A word for those harmonizing in minor: remember the tonality lesson. For an ending that resolves, the dominant chord is played major (the raised leading tone): in A minor, it is E major that brings back to Am, not E minor.
3. Associating a chord with a melody note
The rule: the note must be in the chord
The fundamental rule fits in one sentence: the important melody note must belong to the chord placed underneath. “Important,” meaning the one that falls on a strong beat or that lasts. Brief notes that pass between two, they can be outside the chord: these are passing tones, they slip toward the next note and the ear hears them as a bridge, not as a clash. That is why a single chord can hold under an entire phrase.
Several possible chords under the same note
And here is the most beautiful thing: each note of the scale belongs to exactly three diatonic triads. Three candidates, three vibes. Explore:
4. Harmonizing a melody step by step
Let us move to the workshop. Simple melody: C, D, E, F, G. Two complete harmonizations, the same line, two stories:
Exercise: harmonize 4 notes of your choice
Your turn: choose four notes from the C major scale, write for each its three candidates (the palette table gives you everything), and compose two versions: one bright, one dark. Play them. Then refine with the two finishing tools: cadences to decide where to conclude and where to suspend, and inversions (the “going further” box of chords) to choose your bass notes and make the bass line walk smoothly, step by step, instead of jumping.
To compose and hear these progressions without writing anything down, the guitar progression editor (or its piano version) lets you assemble your chords and compare your two versions, directly in the browser.
And if it clashes? First check the strong beats: an important note outside the chord is heard, change the chord. But a slight clash on a brief passing note is normal, and often pretty. To test different harmonizations and see the palette of each tonality, Twelve Assistant’s Key Chords Diagrams is your workbench.
5. The entire series at a glance
Look at the path traveled. Each lesson gave you a tool, and you just used them all at once:
- Sound and Pitch: everything is vibration, each note is a frequency.
- Musical Notes: 12 pitches, the half step as unit, one fret = one half step.
- Music Intervals: the distances that build everything, from the third to the octave.
- Guitar Scales: a formula of distances, not a list of notes.
- Scale Degrees: each note of the scale has a number and a role.
- Guitar Chord Construction: root, third, fifth: the triad that generates everything.
- Guitar Modes: the same palette can take other colors depending on the center.
- Chord Cadences: the punctuation, tension and resolution.
- Key and Tonality: the system that makes everything hold together around a home.
- Harmonizing Melodies: the complete toolbox, serving your music.
And the most important thing of the entire series: you have done nothing wrong from the start. Your ear was already applying this logic without naming it. Theory replaced nothing: it put words on what your fingers and ears already knew. Now, words and intuition play together.
On your guitar: the final challenge
Single challenge, in three acts. Act 1: hum a simple melody of your invention (five or six notes). Act 2: find its key, write the candidates for each important note, choose. Act 3: play your harmonized melody, then change two chords to change the vibe. There you go: you no longer reproduce music. You make it.
And to keep your find: write your accompaniment chart cleanly and export it to PDF.
Frequently Asked Questions About Harmonization
What is harmonization in music?
Harmonization is choosing the chords that accompany a melody. Where a chord chart is provided ready-made, harmonizing means creating this accompaniment yourself from the melody and the tonality. The basic principle is simple: under each important note of the melody, we place a chord that contains that note, chosen from the tonality’s chord palette. It is the culmination of music theory, because it mobilizes the scale, degrees, chords, cadences and tonality all at once.
How to harmonize a melody?
To harmonize a melody, we proceed in three steps. First, we identify the tonality of the piece, which gives the seven available diatonic chords. Then, for each important melody note, we spot the tonality chords that contain that note, usually two or three possible choices. Finally, we choose among these options according to the desired vibe and the movement of cadences, for example a perfect cadence (V to I) to conclude. The same melody accepts several correct harmonizations, each producing a different color.
How to find the chords that go with a melody?
The fundamental rule is that important melody notes must belong to the chord placed underneath, which makes the whole sound right. We start by finding the tonality, then for each structural melody note we look for the diatonic chords that contain it. For example, in C major, the note E is found in the C chord (C E G), E minor chord (E G B) and A minor chord (A C E). It only remains to choose the one whose color and progression best suit the melody.
What are the diatonic chords of a scale?
Diatonic chords are the seven chords obtained by building a triad on each degree of a scale, only with the notes of that scale. In C major, this gives, in degree order: C major (I), D minor (ii), E minor (iii), F major (IV), G major (V), A minor (vi) and B diminished (vii°). Their quality is always the same in any major tonality: degrees I, IV and V are major, degrees ii, iii and vi are minor, and degree vii is diminished. These seven chords form the palette from which we draw to harmonize.
Can a melody be harmonized in several ways?
Yes, the same melody can be harmonized in many different ways, and this is precisely what makes harmonization a creative act. Since each note belongs to several chords of the tonality, each chord choice changes the color of the accompaniment: the same C can be placed on a stable chord (I), gentle (IV) or melancholic (vi). There is therefore not a single correct answer, but versions with distinct vibes. The role of cadences is then to guide the progression so that the whole tells something.
In Summary
- Harmonizing = choosing the chords for a melody: mechanical (the chord contains the note) + artistic (the chosen vibe).
- The palette = the 7 diatonic chords, deduced from the scale (I IV V major, ii iii vi minor, vii° diminished and rare).
- Each note has three candidates: three chords that contain it, three possible colors.
- Strong beats in the chord, passing tones free: that is the real rule.
- Cadences structure, inversions make the bass walk: the finishing tools of your accompaniment.
You started this series playing charts. You end it knowing how to write them. Welcome to the other side.
Put your first harmonization to sound
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Ten lessons, a complete toolbox, and a certainty: your intuition was right from the start. Theory is now your ally, not your exam.
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