We have 12 notes available to us in Western music.
7 of these notes have just one name:
A B C D E F G
5 of these note have two names:
A#/Bb C#/Db D#/Eb F#/Gb G#/Ab
A# (A-sharp) means “the note that’s higher than A.”
Bb (B-flat) means “the note that’s lower than B.”
The Chromatic Scale
The Chromatic Scale uses all twelve notes, all spaced exactly the same distance apart.
A A#/Bb B C C#/Db D D#/Eb E F F#/Gb G G#/Ab
Each note is a ½ step away from the one next door.
You’ll notice that most of the plain letter names are a whole step apart, except for B to C and E to F, which are a half-step. That’s handy to keep in mind.
Building Scales
The distance from note to note is one way to build a scale.
Chromatic Scale – start anywhere, then H H H H H H H H H
Major Scale – key note, then W W H, W W W H.
Minor Scale – key note, then W H W W H W.
Remember, all the plain letter names are a whole step apart, except for B to C and E to F, which are only a half-step.
C-Major
We’ll start on C, then go W W H, W W W H
C to D is a whole step
D to E is a whole step
E to F is a half step
F to G is a whole step
G to A is a whole step
A to B is a whole step
B to C is a half step
No problem! The notes are all the right distance apart. But what if we run into a half-step when we need a whole step? Well, then we expand it by adding a sharp (#).
G-Major
We’ll start on G, and then go W W H, W W W H…
G to A is a whole step
A to B is a whole step
B to C is a half step
C to D is a whole step
D to E is a whole step
E to F is a half-step → we need a whole step here, so we’ll use F#
F# to G is a half step.
Thus the notes in a G-major scale are G A B C D E F# G.
Ok, we can expand an interval by using a sharp. What if we need to contract a whole step down to a half-step? The answer: use a flat (b).
F Major
Start on F, then go W W H, W W W H…
F to G is a whole step.
G to A is a whole step.
A to B is a whole step, but we need a half-step. We’ll use Bb.
Bb to C is a whole step.
C to D is a whole step.
D to E is a whole step.
E to F is a half step.
The notes in an F major scale are F G A Bb C D E F.
Flat Keys and Sharp Keys (Major Scales)
The keys of G D A E B F# and C# use sharps.
The keys of F Bb Eb Ab Db use flats.
The quickest way to learn which notes are flat and which are sharp in a key is to study the Circle of 5ths. We’ll talk about that in another article.
Conclusion
Learn the 12 notes in the chromatic scale, and you’ll have all the note names you need to build other types of scale. The major scale has a spacing of W W H, W W W H, and you can just count alphabetically up the note names to build it.
Remember that B to C and E to F are both half-steps. All the rest are whole steps. If you need to, you can adjust your intervals using sharps and flats.
Homework:
Build major scales on each of these key notes:
C
G
D
A
E
B
F#
F
Bb
Eb
Ab
Db