Intervals by Ear

An interval is the distance from one note to another. That is all. When a melody jumps, it jumps by an interval. When two people sing harmony, they are singing an interval. And every chord is a stack of intervals. If you can hear the difference between a third and a fifth, you can work out melodies by ear, sing harmony on purpose, and tell a bass player "go up a fourth" instead of humming at them.

Naming intervals by counting

Intervals get two parts to their name. The number counts letter names, including both ends. C to E covers C, D, E, so it is a third. C to G covers C, D, E, F, G, so it is a fifth. The quality word (major, minor, perfect) tells you the exact size, which you check by counting half steps.

Here is the whole set within one octave, measured up from C:

On a guitar, counting half steps is counting frets. Put a finger on any fret, then count up the same string. Three frets up is a minor third. Seven frets up is a fifth. You can check every row of that table on one string in a couple of minutes.

Memory hooks

Nobody learns intervals from a table. You learn them by tying each one to the start of a tune you already hear in your head. Here are hooks that work for most people raised on American folk, church and campfire music. Hum the first two notes of the tune, not the whole thing. The interval is the jump between those two notes unless I say otherwise.

Going up

• Minor second: the shark theme from the movie "Jaws." Two low notes, a half step apart, rocking back and forth.
• Major second: "Happy Birthday." The first two notes are the same pitch. The third note steps up a whole step. That step is your major second.
• Minor third: "Greensleeves." The very first leap, from the pickup note up to the first strong beat.
• Major third: "When the Saints Go Marching In." The first two notes. Also the first two notes of "Kumbaya."
• Perfect fourth: "Amazing Grace." The opening jump from the low pickup up to the long note. Also "Here Comes the Bride" and the bugle call "Taps," which starts with two quick notes on the same pitch and then jumps up a fourth.
• Tritone: "Maria" from "West Side Story." The first two notes of the title word. It sounds like it is about to fall over, and it is supposed to.
• Perfect fifth: "Twinkle, Twinkle, Little Star." First note twice, then the leap up. Also the first big jump in the main "Star Wars" theme.
• Minor sixth: "The Entertainer," the Scott Joplin rag. Skip the first two little pickup notes. The jump from the third note up to the fourth is a minor sixth.
• Major sixth: "My Bonnie Lies Over the Ocean." The first two notes. Also the three-note NBC chime, first to second note.
• Minor seventh: the opening of the original "Star Trek" television theme, the first two notes of the fanfare.
• Major seventh: "Over the Rainbow" from "The Wizard of Oz," but measured from the first note to the third. The first jump is an octave, then the melody drops a half step. First note to that third note is a major seventh.
• Octave: "Over the Rainbow" again, first two notes.

Going down

• Major second down: "Mary Had a Little Lamb," first two notes.
• Minor third down: "Hey Jude," first two notes. Also the playground taunt everyone knows, the singsong two-note "nyah nyah."
• Major third down: "Swing Low, Sweet Chariot," first two notes.
• Perfect fifth down: the theme from "The Flintstones," first two notes.

If a hook does not work for you, swap it. Your own hooks stick better. A Baptist kid and a punk kid will have different lists, and both lists are correct as long as the intervals check out. To check a hook, pick out its first two notes on a guitar string and count the frets between them.

Why songwriters care

Melody shape is mostly intervals. Steps (seconds) feel like talking. Leaps feel like shouting, pleading or praising. A chorus that opens with a big leap, a fourth, fifth or sixth, announces itself. A verse that moves mostly by steps sounds conversational, which is exactly what a story verse wants. Listen to old gospel and you will hear choruses jump up a fourth or fifth on the first word, then walk back down by steps. That shape is no accident.

Harmony singing is intervals too. The standard country and bluegrass harmony sits a third above the melody most of the time, sometimes moving to a fourth or fifth so it stays inside the chord. If you can hear thirds, you can find a harmony part. Sing the melody note, then sing up to the next note of the chord, and you are most of the way there.

Thirds and fifths are the ones that matter most

If you only learn three intervals this month, learn the major third, the minor third and the perfect fifth. Every chord in the next lesson is built from them. A major chord is a major third with a minor third stacked on top. A minor chord flips that order. The outer edge of both is a perfect fifth. Hear those three, and you can tell major from minor by ear, which is the single most useful ear skill for a folk player working out a song from a recording.