Music Theory-Notes

1 Introduction

Coder programmer, music-loving, extroverted, introverted idealist, INFJ. I like guitar and piano. I haven't read music theory for a long time, and I know how to fish at work, so I just sort it out, and the sentences are easy to understand. The words are all typed by myself, so it feels rough to read.

2. Familiar with the piano keyboard and note names

Why is it not called Guitar Window in the software? Because the piano is awesome.

Generally, 88 keys are enough for you.

Divided into seven groups, one group is a CDEFGAB, corresponding to 1234567.

Seven white and five black as a group.

3. Up and down number, recovery number

Only EF and BC have a semitone relationship, because the two keys are next to each other, and there is no black key in the middle.
For example, there is a black key between CDs, C to black key is a semitone, and black key to D key is a semitone, so CD is directly a whole tone.

The black key between the two white keys is the white key C# to the left of the rise, and the white key Db to the right of the fall. But they are different, and they cannot be equal, because there is a "restore key", because one is C and the other is D.


There is no black key between EF and BC, and the relationship between them is semitone, so E is also Fb (F flat), and F is also E# (E sharp). So B is also Cb (C lower), and C is also B# (B sharp).

It is raised by two semitones (one whole step) and lowered by two semitones (one whole step), which is a bit out of line, so we can use it later.

4. How to distinguish different keys with the same note name?

Then group. .

The red arrow below is d2

and there is a simpler way to write it.

5. The relationship between the duration of various notes

Here X can be any one of 1234567. A whole note is twice as long as a half note and four times as long as a quarter note.

6. Song time signature

Denominator: A beat is a fraction of a note.
Numerator: How many beats per measure.

For example, the picture below: denominator: 1 quarter note is taken as 1 beat. Numerator: 4 beats per measure.

If it is 4/4 beat, the whole note is 4 beats, half is 2 beats, and so on as shown in the figure below.

Equally, each measure is 4 beats.

Below this is the most common. A measure in 4/4 time, each of which is a whole note.


Below are 8 eighth notes, also in 4 beats. Because a quarter note is a beat, an eighth note is a half beat.

7. The strength and weakness of the time signature

This is not very important, let's see.
How to keep time?

8. Song speed (BPM)

60BPM, 60 beats per minute.

60BPM is one beat per second.

Below is an 8th note as a beat, and 120BPM is a beat of 0.5 seconds.

9. Dotted notes

Add (extend) half of the original note's duration to the original note's duration.

Based on the time value of the original quarter note, extend half of the quarter note, that is, the eighth note, which is equivalent to adding an eighth note.

The representation is as follows:

10. Triplet

Remember first: the total number of beats of the three generations of twos and triplets represents the total number of beats of the two regular notes below it.

Below are triplets of quarter notes.

A quarter note triplet equals a half note.

A quarter note split into an eighth note triplet. The total number of beats is 1 beat.
Triplet Two: The total number of beats of a triplet represents the total number of rows of the two regular notes below it.
For example, in the triplet below, 3 out of 2, two eighth notes are 1 beat, so the total number of beats is 1 beat.

12. Roll call and numbered notation

CDEFGAB does not necessarily correspond to 1234567, but the roll call must correspond to 1234567.
CDEFGAB corresponds to 1234567 only when 1=C.

Add 1 dot to the top, 1 octave higher. Add 2 points, two octaves higher.

13. Natural major (white key)

That is, 1=c, no matter which octave rule is consistent internally.

Remember the following: whole half whole whole whole half, because the following G and D majors can be inferred by this formula.

According to: whole half whole whole whole half to derive the following G major, 1=G, G followed by a whole tone is A, A followed by a whole tone is B, B followed by a half tone is C, C followed by a whole tone is D, D followed by a whole step is E, E followed by a whole step is F sharp (#F), #F followed by a semitone is G.
Note: Why doesn't #F drop G? Because the seven phonetic names are required to appear in sequence.


Based on the same reasoning: whole whole half whole whole whole half to push to D major.

14. Natural Major (Black Keys)

The previous sections all start from the white keys, and can also start from the black keys.
The black key does not have its own sound name. Its sound name is obtained through the rising or falling of the left and right white keys. When starting with a black key, it is usually represented by falling x, because falling is easier to express than rising, see the explanation below.


For example, C sharp and D flat are one, but D flat (bD) is simple. look down

For another example, both D sharp and E flat represent the same black key, but E flat is written simply.

15. Natural Minor

It is too troublesome to remember this: full half full half full

can find out its relationship with the major key through the minor key. (Push back one whole tone and one semitone first, find the scale corresponding to the major, and then move the last two scales of the major to the front, to be precise, move 67)

For example: A minor, look for its relative major, one whole tone and one semitone backward, it is C, the corresponding scale of C is: CDEFGAB, and moving AB to the front is the scale of A minor - ABCDEFG. The steps are as follows:
1. Find the major key related to A:

2. Find the scale corresponding to C major:
3. Move the last two corresponding to the major to the front (to be precise, move 67 to the front), which is the scale corresponding to the minor :

In the same way, here is another example: 1 in E minor
. The major key related to E minor is G (a whole tone and a semitone in the back)

2. Write the scale corresponding to G major

3. Move the last two corresponding to the major to the front (To be precise, move 67 two to the front) is the scale of E minor.

One more card: D minor
1. Find the corresponding major key as F (one whole step backward, one semitone)

2. Find the scale corresponding to major F:

3. Move: (to be precise, move 67 two to the front )

17. The basic concept of interval

Interval: The distance between sounds, in degrees.
For example, how many degrees does CA have? There are several white keys between them, including the white keys where they are located.

There are several degrees of white keys, but it should be noted that it includes the white keys where they are located.


So how many degrees are there between the black keys below? You need to restore the black key first, and then count. If you don’t restore it by writing, the counting is different. If you raise d, you will restore it to the left, and if you drop E at the same position, you will restore it to the right. Therefore, the same position has different writing methods (D#, Eb ) the degree of output is not the same as

Example: How many degrees is there from C# to E? First restore to C, and then count to 3 degrees.

How many degrees from Db to E? First restore to D, and then count to 2 degrees.

18. Attributes of intervals (pure, large)

21. The name of the music

22. Three chords

23 Seventh chords

24. Nine chords

25. Suspension chord

26. Inversion chords

29. Medieval mode