Intervals: The Distance Between Two Notes

So far, you've measured the distance between notes in half steps and whole steps, row by row. That's an excellent habit, and we're going to keep it. But musicians also give each distance a name, and that name tells you more than a number does: it tells you about a color. The distance between two notes is called an interval. In this lesson, you'll learn to name intervals and, above all, to hear them.

Two notes, two ways to hear them

Let's start by listening. In the figure, the same pair of notes is played twice: first one after the other, then both together. The two notes are C4 and G4.

When the two notes follow each other, we call it a melodic interval: that's what a melody or a bass line does when it jumps from one note to another. When they sound together, we call it a harmonic interval: that's the raw material of chords. The name of the interval is the same in both cases, and it doesn't change whether you go up or down either. From G4 down to C4, the distance is exactly the same as from C4 up to G4.

The number comes from counting letter names

An interval has a number first. To find it, count the letter names from the first note to the last, counting both ends. From C to G, you go through C, D, E, F and G: that's five letter names, so it's a fifth. From C to E, you count three names: it's a third. Two neighboring names make a second, four make a fourth, six a sixth, seven a seventh, and eight names bring you back to the same letter: that's the octave.

The number alone isn't enough, because the letter names aren't all the same distance apart. From C to E, there are four half steps; from D to F, there are only three, because the step from E to F is just one half step. Both are thirds, but they don't sound the same. So we add a quality to the number, which tells you the exact number of half steps.

Major, minor and perfect

Seconds, thirds, sixths and sevenths come in two sizes. The larger one is called major, and the smaller one, a half step shorter, is called minor. You already know the major third and the minor third: the third note is what makes all the difference between the major scale and the minor scale.

Fourths, fifths and octaves have only one normal size, which is called perfect. So there's no such thing as a major fifth or a minor fifth. These are the most stable intervals, the ones whose two notes blend into each other best, and we'll see why in the next lesson. Here are the twelve intervals from the minor second to the octave, all measured from C4. Read the table with the grid in mind: the number of half steps is the number of rows you move up.

Now listen to the main ones, with both notes played together. Don't try to recognize them with certainty yet. Just notice that some of them blend, like the octave and the fifth, and that others rub, like the minor second and the major seventh.

Augmented and diminished

There are two more qualities, less common, which are mostly there so we can name notes correctly. An augmented interval is one half step larger than a major or perfect interval. A diminished interval is one half step smaller than a minor or perfect interval. From C to G♯, for example, you have an augmented fifth: five letter names, but eight half steps instead of seven.

You may have noticed that eight half steps is also the minor sixth, from C to A♭. On the grid, G♯ and A♭ sit on the same row: the sound is identical, and only the name changes, depending on which letter you use. This is the enharmonic spelling you met with sharps and flats. For the sound, the detail doesn't matter; for understanding a chord, it matters a lot, and we'll come back to it with the augmented chord.

The tritone, the interval that splits the octave in half

Six half steps is exactly half an octave. This interval contains three whole steps, which is where its name comes from: the tritone. Spelled from C to F♯, it's an augmented fourth; spelled from C to G♭, it's a diminished fifth. Both names point to the same row. In the C major scale, it appears in only one place, between F and B.

Listen to it, then compare it with the perfect fifth, one half step higher. The tritone sounds unstable, as if it were waiting for something to follow. It also has a surprising quirk: if you put C above F♯ instead of below it, you still get six half steps. It's the only interval that keeps its six half steps when you flip it, even though its name changes from augmented fourth to diminished fifth. That suspended character makes it a valuable tool for building tension.

Counting an interval on the grid

On the grid, the method comes down to two moves. First, count the rows between the two notes, without counting the starting row: that gives you the number of half steps. Then check with the letter names that the number is right. With a little practice, a few visual landmarks become automatic: three rows for the minor third, four for the major third, seven for the fifth, twelve for the octave. Those four alone are enough to build almost every chord in this course.

Now let's move on to the ear, which is what matters most for a producer. Start with a few very different intervals, for example the major third, the fifth and the octave, then add one at a time. Sing or hum the second note before you check. A few minutes a day will get you much further than a long session every now and then.

You've heard that some intervals blend and others rub. The next lesson explains why, and how to use that rubbing on purpose instead of putting up with it.