Notes, Intervals and Scales

A guitar's neck holds four dozen or so different pitches, a keyboard four octaves, a bass a little fewer. Here they all are. It looks like a lot; it isn't, and what follows is why. Pick your instrument under the figure — everything below follows it.

Neighboring notes are 1 semitone apart: one fret up a string, one key to the right, black keys included. Here are two of them ♪, up and back.

The distance between two notes is called an interval. It is measured in semitones, and the ones you will meet most have names: 1 semitone ♪ is also known as a minor second — played together, the two notes sound a bit rough.

7 semitones ♪ is also known as a perfect fifth — much smoother. Count them up from the first note, a fret at a time, and you arrive at the second; then hear the two together.

But the most important interval is the octave ♪ — 12 semitones, the twelfth fret of any string. Notes that are an octave apart are maximally consonant: together they sound stable and simple, almost like one note.

Because they sound like the same note, notes an octave apart have the same name.

And they occur in every octave: here is every C on the instrument — the same note in five or six places, and the pattern of where they sit never changes.

In NoSheet, notes an octave apart always have the same color as each other. Which color that is varies with context — it follows the root, which comes next — but the rule holds: one name, one color, in every octave.

That means: 12 notes in every octave, 12 colors, repeating across the instrument. Every scale, chord and melody you will ever play is a choice of some of these twelve.

Most music doesn't use all 12 notes in any octave equally.

Most music only really uses 7 of the 12 — barely over half.

Most music also uses each note differently — most importantly by defining a root ♪: the note that is home, the one everything else is heard against.

The other notes are some interval above that root ♪, marked by a color and the interval: the 2, the 3, the 4, the 5, the 6, the 7 — one at a time, up from the root.

Which notes you use, and how you use them — that's a scale. The numbers are called scale degrees, and they are the most useful idea on this site: each scale degree has a unique sound against the root, and therefore a unique role. You're seeing the most common scale here: the C major scale.

If you shift all the notes by the same amount, you still have a major scale, but with a different root — G major ♪, D major ♪, A major ♪. Pick any root above the figure: the shape moves, the numbers don't. The major scale is the core of modern music — everything exists relative to it.

Shifting only some of the notes gives you different scale types: lower the 3, the 6 and the 7 and C major becomes C minor ♪. Tap between the two scales above the figure and watch which notes move.

In the same way, you can use smaller sets of notes. Drop the 4 and the 7 and what remains is the major pentatonic ♪; keep only the 1, the 3 and the 5 and you have the major triad ♪ — the chord, 1 3 5. Tap the sets above the figure to see how the smaller ones exist within the larger.

The key: using a scale intentionally will enable you to create stuff that sounds musical — and it will be way easier than trying to just play random notes until it sounds good. That is what NoSheet trains: hear a phrase, feel which degrees it uses, find them on the instrument. The root moves every round, so it is the numbers you learn, not the frets — and the rest of this page is about why that is the thing to learn.

Here is a short tune over four chords, twice: in C, and in G. Tap either to hear it. It is the same tune — the same rises, the same rests, the same chords doing the same jobs — a little lower the second time. Now read the labels. Every chord name changed, and every note's; nothing you can hear did. Someone who knows this song as names knows it in one key.

Flip the labels to numbers. The two pictures are now the same picture: the same chords by number, the melody starting on the same degree and resting on the same degrees, in both. That is what the numbers are for. "C to F" is one move in one key; "1 to 4" is the same move in twelve keys, and you will hear it in most songs you know. (The colors never changed: in NoSheet a color is a number.)

The numbers name a scale; they name a chord the same way. 1 3 5 ♪ is a major triad, on any root. Lower the 3 and it is a minor triad ♪ — 1 ♭3 5. Add the ♭7 to the major triad and you have the dominant seventh ♪, the chord that pulls home in most songs; add the 7 instead and it is a major seventh ♪; ♭3 and ♭7 together make the minor seventh ♪. Five chords, one short sentence each, and every sentence is true on every root and every instrument. "C7" is not a name to memorize but a recipe you can read: C, then 1 3 5 ♭7. Tap between the five above the figure and watch what moves — never more than a note or two.

Put the two together and you can say what a chord is doing in a key. Here is the G chord inside C major: its three notes plain, the rest of the scale shrunk behind them. Read it both ways at once — against the key it sits on the 5 and holds the key's 5, 7 and 2; against its own root it is 1 3 5 (the eye at the row's end hides the scale, and the labels become the chord's own). When a player says "land on a chord tone", this is the picture: the key's seven notes, and which three the chord under you is holding right now. Tap the other chords above the figure — C, Dm, Em, F, Am — and watch the three move through the same seven notes. The chords of a key have numbers of their own, the roman numerals; Chords in a key draws all of it.

If the numbers are this useful and this simple, why doesn't everyone learn them in their first month? Because every instrument teaches its own absolute thing first — the guitar its shapes, the piano its white keys, the sheet and the tab a position for every note — and a number is not a position. It is a distance from a home that is sounding. It means nothing until a root is playing, until the instrument is seen from that root, and until the root has moved often enough that a remembered shape can't stand in for it. A book shows one key, silently. A teacher can't move the root for you at your pace for an hour. So "theory" became something you read, and reading is what a beginner is right to skip — and then everything learned as names has to be learned again, once per key.

What it takes is pictures that move, sound, and a lot of doing. That is what this page has been: a root that sounds, an instrument colored from it, a root you moved twelve times with a tap, five chords built from one, a chord found inside its key. A page couldn't do that before, and a beginner who has just seen it is a month ahead.

What a page still can't do is the rest: the hundreds of repetitions with your hands and your ears, the root moving every time, until the 4 is just the 4. Two places to do that. On this site, the loop: a phrase from the major pentatonic or the whole major scale, played back on your instrument, the root jumping every round so the numbers are all you can hold on to. And in the app, the same loop listens to you play it back — and the whole curriculum, from the root and the fifth to the modes, is built on it.