Harmonizing a Major Melody without Reading Music
If you’ve written a melody while on a walk, in the shower, or playing with one hand on a keyboard, you might wonder how to pick the right chords to go along with it.
This is known as harmonizing a melody.
In this post, we’ll look at some practical techniques you can use to find chords that fit your melody. Keep in mind that you can use these same techniques to replace or improve a chord progression that isn’t working for you.
Many resources on harmonization assume that you can read music. In this post, we’ll assume you can’t. But these techniques should be helpful for anyone.
Determining the scale and chords related to your melody
I’ve written in detail about how to find the key for a melody. If you don’t know what key your melody is in and don’t know how to figure it out, start there.
In general, your melody will either be in a major key, a minor key, or in some other mode.
In this post, we’re going to focus on major key melodies. Later posts will look at how to harmonize minor key and modal melodies.
Ok, so from here on we’re assuming you have a major key melody. The first thing to do is look up the scale degrees and chords found in that key.
First, look up your key in this table (the first note is also the name of the key). Write down the scale degrees and notes for your key:
1 - 2 - 3 - 4 - 5 - 6 - 7 -------------------------------------- C - D - E - F - G - A - B Db - Eb - F - Gb - Ab - Bb - C D - E - F# - G - A - B - C# Eb - F - G - Ab - Bb - C - D E - F# - G# - A - B - C# - D# F - G - A - Bb - C - D - E Gb - Ab - Bb - Cb - Db - Eb - F G - A - B - C - D - E - F# Ab - Bb - C - Db - Eb - F - G A - B - C# - D - E - F# - G# Bb - C - D - Eb - F - G - A B - C# - D# - E - F# - G# - A#
For example, if your song is in the key of F major, you’d write down:
1 - 2 - 3 - 4 - 5 - 6 - 7
F - G - A - Bb - C - D - E
Next, look up the chords for your key:
I - ii - iii - IV - V - vi ------------------------------ C - Dm - Em - F - G - Am Db - Ebm - Fm - Gb - Ab - Bbm D - Em - F#m - G - A - Bm Eb - Fm - Gm - Ab - Bb - Cm E - F#m - G#m - A - B - C#m F - Gm - Am - Bb - C - Dm Gb - Abm - Bbm - Cb - Db - Ebm G - Am - Bm - C - D - Em Ab - Bbm - Cm - Db - Eb - Fm A - Bm - C#m - D - E - F#m Bb - Cm - Dm - Eb - F - Gm B - C#m - D#m - E - F# - G#m
If your melody is in F major, you’d write down:
I - ii - iii - IV - V - vi
F - Gm - Am - Bb - C - Dm
[Note that in the chord table above (and in this post), we’re leaving out the unstable and difficult to use diminished chord on the seventh degree (vii°).]
These notes and chords you’ve written down will come in handy in what follows.
In fact, you could stop here and just audition these six chords over your melody until you find a combination that works.
But this can be a time-consuming and random process, so we’re going to explore a more structured way to find combinations that sound good.
Harmonizing a melody with the core chords
If your melody is based entirely on the major scale, you should always be able to harmonize it with the three core chords of the major key: I, IV, and V.
A major scale has seven notes that we can number 1 to 7. Here’s how they sound in the key of C major:
Together, the core chords (I, IV, and V) contain all seven notes of the major scale:
I: 1 3 5 IV: 4 6 1 V: 5 7 2
This means that whatever major scale note you’re singing (or playing), there’s a core chord that can fit with it. Let’s look at it from that perspective:
Major scale: 1 2 3 4 5 6 7
I: ✓ ✓ ✓
IV: ✓ ✓ ✓
V: ✓ ✓ ✓
So, for example, if you’re singing the 1st note of your scale, you can choose either the I or the IV chord to harmonize with it.
You can write a more specific version of these tables for the key your melody is in. For example, if we use the key of F major again, you could transform the above table to:
Major scale: 1 2 3 4 5 6 7
F G A Bb C D E
(I) F: ✓ ✓ ✓
(IV) Bb: ✓ ✓ ✓
(V) C: ✓ ✓ ✓
The core chords in the key of F major are F (I), Bb (IV), and C (V).
Using the core chords intuitively
You might be thinking that you need to have all this theory in mind to use the core chords effectively. But that is not at all true.
What the theory tells us is that at any point in our major scale melody, we can choose a core chord to accompany it.
And what this means in practice is that you can just try them out as you sing (or as you listen to the melody playing on repeat).
This is a great place to start when it comes to harmonizing melodies. Since you’re only working with three chords, it won’t be long before you start to get a feel for how they relate to each other.
I’d also recommend recording more than one version. This way you can compare and pick the one that works best. Plus, it’s a great way to learn.
Matching the core chords to the notes
The intuitive approach will often be all you need when it comes to harmonizing with the core chords. But you can also intentionally match chords to notes.
Not every note in a melody has equal weight. This is important to keep in mind as you choose chords.
In particular, notes that fall on the first and third beats are often more significant when it comes to harmonies.
Two of the most common ways to structure a chord progression are to choose either one or two chords per bar. In the common 4/4 time, a bar has 4 beats (think taps or counts).
So at least as a starting point, let’s adopt these principles for each bar:
- Pick one or two chords to be played over the bar (one after the other).
- If we pick one chord, it lasts the whole bar (4 beats). If we pick two chords, each lasts half the bar (2 beats)
- Pick chords that contain the notes on beats 1 and 3.
This means that if we pick two chords, the first chord will contain the note on beat 1 and the second chord will contain the note on beat 3.
But what if we pick one chord? In theory, it should contain both the note on beat 1 and the note on beat 3. If we stick to our three core chords (I, IV, and V), this will be possible if those two notes are:
Two of: 1, 3, or 5. (I)
--or--
Two of: 4, 6, or 1. (IV)
--or--
Two of: 5, 7, or 2. (V)
If none of these are true, you have two options. Either you pick a different chord to start on beat 3 or you allow for a more complex or dissonant harmony.
Don’t let all of these numbers fool you. In the end, your choices should always depends on your ears.
Adding the color chords to our palette
You should be able to harmonize any major key melody with the core chords alone. But you might quickly notice that they create a relatively neutral harmonic “feel”.
They are all major chords, and in a way they act as the skeleton of the major key (which is why I call them the core chords).
If you want to start exploring more colorful options, it’s time to introduce what I refer to as the color chords. In a major key, these are ii, iii, and vi.
They are all minor chords, and they introduce new combinations of our major scale notes:
ii: 2 4 6 iii: 3 5 7 vi: 6 1 3
Their addition to our list of chords creates a number of new options from the point of view of harmonizing a single note:
Major scale: 1 2 3 4 5 6 7
I: ✓ ✓ ✓
ii: ✓ ✓ ✓
iii: ✓ ✓ ✓
IV: ✓ ✓ ✓
V: ✓ ✓ ✓
vi: ✓ ✓ ✓
Again, you can create a more specific version of this diagram for the key your melody is in (after writing down the scale and chords of your key as described in the first section above).
For example, here’s what it would look like for the key of F major:
Major scale: 1 2 3 4 5 6 7
F G A Bb C D E
(I) F: ✓ ✓ ✓
(ii) Gm: ✓ ✓ ✓
(iii) Am: ✓ ✓ ✓
(IV) Bb: ✓ ✓ ✓
(V) C: ✓ ✓ ✓
(vi) Dm: ✓ ✓ ✓
Using the color chords through substitution
Using the color chords intuitively will be more challenging than just using the core chords.
In part that’s because most major key progressions will use at least some core chords as well. We now have many more possible combinations than we had with just three chords.
Of course, it’s worth trying anyway and there’s a lot to learn by intuitive experimentation. But there’s also a more systematic way to approach it.
That approach is called substitution.
Each color chord shares 2 notes with one of the core chords. In practical terms, this means that each color chord can be substituted for a core chord:
ii <-> IV iii <-> I vi <-> I
If you start by intuitively writing a progression using just I, IV, and V, you can then narrow your options considerably for where to play color chords.
After you have a core chord progression you like, try replacing the I chord with either iii or vi. And try replacing the IV chord with ii.
You don’t need to replace every one! Again, the best approach is to experiment and rely on your ears.
Write more than one version and compare them.
If you are writing a major key progression from scratch, there’s no need to limit yourself in this way (although you still can!).
But when you’re starting from a melody, there are far fewer chord choices that will sound good. Substitution is one way to make the challenge of choosing chords easier.
What if your melody borrows notes from outside the major scale?
It’s not uncommon for popular music to borrow chords and notes from outside a single key.
Whether you realize it or not, you might also do that when coming up with a melody, whether singing or playing on an instrument.
Nevertheless, it’s normally the case that a melody will at least mostly be in one key (at least the melody for a single section like a verse or chorus).
If your melody does borrow notes, the techniques in my post on key-finding will still help narrow down the underlying key. But you’ll find that you can’t neatly fit all of the notes into the table of scale degrees 1 to 7 found in the first section of this post.
An in-depth treatment of harmonizing more complex melodies will have to wait for a future post, but there are a couple of things you can try in the meantime.
First, if none of the borrowed notes fall on the 1st and 3rd beats of the bar, then you might be able to get away with following the exact techniques described in this post (and effectively ignoring the out-of-key notes).
In that case, the borrowed notes might function more as passing tones or embellishments. They might constrain which in-key chords sound good, but otherwise still work with the six major key chords we’ve been discussing above.
However, if they do fall on the 1st and 3rd beats, then they will probably have a more significant impact on which choices sound good.
It can still be worth exploring the core and color chords to discover if you can find an interesting dissonance or complex harmony. But at this point, you might want to try out borrowed chords.
We’ll have to leave harmonizing borrowed notes for a future post. For now, you should have enough resources to choose chords for many (if not most) of the major melodies you’ll come up with.
All that’s left is to explore!