What Is a Key? The Note That Feels Like Home
You're going to find out what the tonic is, the note that sounds like home, and exactly what the “Key” field shown by your software or by a sample site means.
In the last two lessons, you built scales: seven rows chosen out of twelve. But a scale on its own doesn't tell the whole story. You've already noticed that C major and A minor use exactly the same white keys, and yet one sounds bright and the other dark. What separates them is the note the music revolves around. That's the subject of this lesson.
Same notes, different home
Listen first. The first loop plays over a bass that holds C3. All of its notes are white keys, and it ends on C4.
The second loop uses the same melodic shape, moved down two white keys. The bass now holds A2, and the melody ends on A3.
The shaded rows are identical in both figures. Yet the first loop settles on C and sounds clear, while the second settles on A and sounds melancholy. The note the music comes to rest on, the one that gives you the feeling of having come home, is called the tonic.
The tonic and the key
The tonic is the first degree of the scale, the resting note that everything comes back to. A key, for its part, combines a tonic and a scale: we say “C major”, “A minor”, “F sharp minor”. So saying that a track is in A minor means two things at once: that its notes come mostly from the minor scale, and that A is home.
A good test is to stop the same phrase on two different notes. Listen to this phrase in C major, which ends once on the tonic and once on the second degree.
The first version closes like a sentence with a period. The second hangs in the air, like a question. That's exactly what the tonic does: it closes. The other notes of the scale aren't any less beautiful; they simply have a different role, more or less far from home.
Relative keys
Let's go back to C major and A minor. Two keys that have exactly the same notes but not the same tonic are called relative keys. A minor is the relative minor of C major, and C major is the relative major of A minor. This isn't an exception: every major key has its relative minor, and every minor key its relative major.
There are two ways to count your way to the relative. From the major tonic, go down three half steps: from C, you land on A. Or take the sixth degree of the major scale: in C major, that's A again. In the other direction, from a minor tonic, go up three half steps: from E, you land on G, so E minor is the relative of G major.
The next table gathers the pairs of relative keys you'll come across most often. Each row brings together two keys that share exactly the same seven notes.
| Major key | Relative minor | Shared sharps or flats |
|---|---|---|
| C major (C) | A minor (Am) | none |
| G major (G) | E minor (Em) | F♯ |
| D major (D) | B minor (Bm) | F♯ C♯ |
| F major (F) | D minor (Dm) | B♭ |
| B flat major (Bb) | G minor (Gm) | B♭ E♭ |
| E flat major (Eb) | C minor (Cm) | B♭ E♭ A♭ |
Don't confuse relative keys with keys that only share their tonic. C major and C minor have the same home, but not the same notes: C minor lowers three degrees, as you saw in the previous lesson. So they aren't relatives.
Note to note: whole step, whole step, half step, whole step, whole step, whole step, half step.
Characteristic note: the major third, E. It sits four half steps above the tonic and gives major its bright, stable color.
On the grid, the shaded rows are the notes of the scale across an octave and a half: any note you place on those rows stays in the scale. The pattern drawn goes up one octave, then comes back down.
The key signature, in two sentences
In sheet music, the sharps or flats of the scale are written once and for all at the start of each line: that's the key signature. So two relative keys have the same key signature, and it's the music itself, not the key signature, that tells you which of the two is the right one.
What the “Key” field means
In your software and on sample sites, you'll see a “Key” field everywhere. It tells you the key, that is, a tonic and, most of the time, whether it's major or minor. The spellings vary: “Am”, “A min”, “Amin” and “A minor” all mean A minor. A lowercase “m” after the letter signals minor; a letter on its own, or followed by “maj”, usually signals major.
This information is mainly there to tell you whether two elements will work together without any adjustment. A pad loop in A minor and an 808 line in A minor share the same home and the same notes. A loop in C major will work too, since it's the relative, as long as your bass keeps asserting A as home. A loop in E flat minor, on the other hand, has only two notes in common with A minor: it will rub almost everywhere, and you'll need to transpose it.
Am, 8A and the DJ wheel
On some sites and in DJ software, you'll sometimes see codes like “8A” or “8B” instead of key names. They come from a system called the Camelot wheel, designed to help DJs mix compatible tracks. The keys are arranged on a circle numbered from 1 to 12; the letter A stands for minor keys and the letter B for major keys.
So 8A is A minor and 8B is C major: the same number brings two relatives together. Two neighboring numbers, such as 8A and 9A, that is, A minor and E minor, differ by only one note. You don't need to learn this wheel to produce; just remember that a code like 8A names a key, written differently from “Am”.
Here's a two-bar loop. Its notes are G, A, B, C, D, E and F♯, and its bass holds E while the melody ends on E. What's its key, what's its relative, and how might a sample site display it?
Knowing what a key is is one thing; recognizing it in a track or a sample is another. That's what we'll practice in the next lesson.