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In this post we will talk about scales.

First be sure you fully understand distance between notes

Now that we know what a semi-tone and a whole-tone (two semi-tones) are, it is easy.

First, we will give the definition of what is a scale, then study the example of **C** major scale so we can learn about the "major scale pattern".

##### What is a scale ?

A scale is a set of different notes within an octave. But that is not the easiest sentence to understand, so let's begin with a well known example.

##### The C major scale

Play on your keyboard, in ascending direction, and then in descending direction, all the white notes from **C** to **C**.

That is : **C - D - E - F - G - A - B - C**

The last **C** is redundant with the first **C**, but we always play it because it gives a feeling of resolution. So, to be clear:

The **C** major scale is the set "**C - D - E - F - G - A - B**"

You know the sound of this scale, keep it in mind!

Now let's translate it in term of "distance between notes". (remember, the distance between notes are easy to see on the piano keyboard)

- between
**C**and**D**there is 1 whole-tone - between
**D**and**E**there is 1 whole-tone - between
**E**and**F**there is 1 semi-tone - between
**F**and**G**there is 1 whole-tone - between
**G**and**A**there is 1 whole-tone - between
**A**and**B**there is 1 whole-tone - between
**B**and**C**there is 1 semi-tone

If we put it in a table, writing 1 for a hole-tone and ½ for a semi-tone, we get:

the distance between | C and D | is | 1 |

the distance between | D and E | is | 1 |

the distance between | E and F | is | ½ |

the distance between | F and G | is | 1 |

the distance between | G and A | is | 1 |

the distance between | A and B | is | 1 |

the distance between | B and C | is | ½ |

##### The major scale construction

This last column is in fact the recipe to make a major scale, the "major scale pattern":

the distance between | - and - | is | 1 |

the distance between | - and - | is | 1 |

the distance between | - and - | is | ½ |

the distance between | - and - | is | 1 |

the distance between | - and - | is | 1 |

the distance between | - and - | is | 1 |

the distance between | - and - | is | ½ |

What happens if we want to start the same pattern beginning on D?

We just write D as the first note.

the distance between | D and - | is | 1 |

the distance between | - and - | is | 1 |

the distance between | - and - | is | ½ |

the distance between | - and - | is | 1 |

the distance between | - and - | is | 1 |

the distance between | - and - | is | 1 |

the distance between | - and - | is | ½ |

The last column is the recipe, so we don't want to change it ! What we have to do, is to fill the second column with the right notes.

###### first line:

Beginning on D, what is the next note if we want to have a whole-tone?

Look at your piano keyboard: it's E

the distance between | D and E | is | 1 |

the distance between | E and - | is | 1 |

###### second line:

Beginning on E, what is the next note if we want to have a whole-tone?

Look at your piano keyboard: it's F♯

the distance between | D and E | is | 1 |

the distance between | E and F♯ | is | 1 |

the distance between | F♯ and - | is | ½ |

###### third line:

Beginning on F♯, what is the next note if we want to have a semi-tone?

Look at your piano keyboard: it's G

the distance between | D and E | is | 1 |

the distance between | E and F♯ | is | 1 |

the distance between | F♯ and G | is | ½ |

the distance between | G and - | is | 1 |

###### fourth line:

Beginning on G, what is the next note if we want to have a whole-tone?

Look at your piano keyboard: it's A

the distance between | D and E | is | 1 |

the distance between | E and F♯ | is | 1 |

the distance between | F♯ and G | is | ½ |

the distance between | G and A | is | 1 |

the distance between | A and - | is | 1 |

###### fifth line:

Beginning on A, what is the next note if we want to have a whole-tone?

Look at your piano keyboard: it's B

the distance between | D and E | is | 1 |

the distance between | E and F♯ | is | 1 |

the distance between | F♯ and G | is | ½ |

the distance between | G and A | is | 1 |

the distance between | A and B | is | 1 |

the distance between | B and - | is | 1 |

###### sixth line:

Beginning on B, what is the next note if we want to have a whole-tone?

Look at your piano keyboard: it's C♯

the distance between | D and E | is | 1 |

the distance between | E and F♯ | is | 1 |

the distance between | F♯ and G | is | ½ |

the distance between | G and A | is | 1 |

the distance between | A and B | is | 1 |

the distance between | B and C♯ | is | 1 |

the distance between | C♯ and - | is | ½ |

###### last line:

Beginning on C♯, what is the next note if we want to have a whole-tone?

Look at your piano keyboard: it's D

the distance between | D and E | is | 1 |

the distance between | E and F♯ | is | 1 |

the distance between | F♯ and G | is | ½ |

the distance between | G and A | is | 1 |

the distance between | A and B | is | 1 |

the distance between | B and C♯ | is | 1 |

the distance between | C♯ and D | is | ½ |

We just constructed the scale of D major : "**D - E - F♯ - G - A - B - C♯ - D**"!

The sound is very similar to the **C** major scale, isn't it? That's because, like "**C - D - E - F - G - A - B - C**", the set of notes "**D - E - F♯ - G - A - B - C♯ - D**" is a major scale.

You may wonder : why did we call the third note **F♯**, and not **G♭**?

It is because, as a general rule (for a lot of scales, but not all of them ), we like scale with consecutive letters, nothing else.

Now that we know the rules to construct a major scale, let construct all of them...