Quint circle of keys

2024 Author: Leah Sherlock | [email protected]. Last modified: 2023-12-17 05:25

The circle of fifths helps to conveniently memorize musical harmony and study parallel keys. It allows you to effectively learn modes and key signatures, so understanding how it works is extremely important for all students mastering music theory.

The concept of a quarto-quint circle

The quarto-quint circle is a special system of arrangement according to the degree of kinship, that is, the difference in the number of signs of one from the other of different keys. In graphical form, it is visually depicted as a diagram of a closed circle, in which, on the one hand, the sides are located along the ascending fifth row of tonality with sharps, and on the left, along the descending row, with flats.

If you move clockwise around the circle of fifths, the first step (tonic) of subsequent major keys will be spaced upwards from the previous ones by an interval equal to five steps, that is, by a pure fifth. In this case, one sign will always be added in the key - sharp. In the counterclockwise direction, the descending interval will also be 3.5 tones. At the same time, in each subsequent key will increasenumber of flats.

What is this system used for?

The quarto-fifth circle of keys is used to determine the number of characters (sharps, flats) in the key. It is also used to search for related keys and determine the degree of their proximity. Related tonalities of the first degree include majors and minors, which differ from the original one by one accidental sign. They also include those in the circle in the neighborhood, parallel to them and to the original one. The closer the keys are to each other in the circle, the higher the degree of their relationship. In the event that there are more than three or four steps between them, then there is no closeness. Many composers used the principle of movement in a circle when writing their works, for example, F. Chopin ("24 Preludes") and J. S. Bach ("The Well-Tempered Clavier"). In the 19th-20th centuries, it was reflected in jazz compositions and rock music, but was used in a transformed form called the "golden sequence" (not only a fifth, but also a quart was used to build chords).

The principle of finding major keys with sharps

So, let's see how the circle of fifths "works" and how accidentals are added in different keys. The principle of operation of the system is as follows: first, one initial key is taken. We know her tonic. To determine the first degree of the next key, let's count five notes up. The tonic of a related key will be on the fifth step of the original, that is, on its dominant. Thus, the interval forThe quint serves as a calculation. It is because of the use of five steps for defining keys that the circle of fifths got its name. Now let's look at accidentals. The rule is this: they are transferred from the original key to the next, plus one sign is added to them (to the sixth step) - sharp.

Let's consider the key of C major, which has no accidentals (sharps and flats). Its tonic is the note do, and the dominant is s alt. Therefore, according to the principle of the circle of fifths, the next tonality will be G-major (otherwise G-dur). Now let's define the accidental sign. In the resulting related key, step No. 6 is fa. It is on it that there will be a sharp. To determine the next tonality from G, set aside an interval equal to five steps. Its dominant is re. This means that the next key will be D-major (D-dur). It will already have two accidental signs: from the previous key (F-sharp) and C-sharp joining at the sixth step. By analogy, you can find all the other keys. When determining the one that has seven signs with the key, the circle will close enharmonically.

Major circle of fifths with flats

Flat major keys, unlike sharp ones, on the contrary, go down in pure fourths. The tonic of C major is taken as the starting point, since C-dur has no accidentals. Counting down five steps, we get the tonic of the second key after it - F-major. In flatIn keys, accidental signs appear not on the sixth, but on the fourth degree of the mode, that is, on the subdominant. In F major, it's B flat. Having passed the entire circle of fifths, we obtain the following major flat keys: C major, F major, B flat major, E flat major, A flat major, D flat major, G flat major, C -flat major. Moreover, the latter has as many as seven flats. Further, the circle is anharmonically closed. Of course, after that, other keys appear in a spiral - with double flats, but they are used quite rarely due to their complexity.

Minor keys in a circle of fifths. What is their construction principle?

So, we have considered 12 major keys. Each of them has related minors. You can see this in the circle of fifths shown in the picture above. The scale of the related minor key scale is built on the same sounds as the major one. But it starts on a different note. For example, related keys without accidentals C major and A minor are built on simple sounds. In C-dur, do, mi and sol are stable sounds. They form a major tonic triad.

The interval between the tonic and the third is the major third. At the first step in the note A, the sounds la, do and mi form a stable triad. The interval between the first and third steps is equal to 1.5 tones (small third). This makes a minor a minor key. A minor and C major are parallel: the tonic of the first is spaceda minor third down from the tonic of the second. Their important characteristic is the same number of accidentals. For example, G minor and B flat major contain two flats in the key, and E minor and G major contain one sharp. In parallel keys, the same scale is used, so a melody sounding in a major mode can quite easily transform into a minor one, and vice versa. This technique is often used in Russian folk songs (see "And we sowed millet"). Thus, if we lower the tonics of all major keys by a minor third down, we get a minor fifth circle. The figure shows accidentals that are found in each sharp and flat minor key.

Instead of a conclusion

So, in this article we examined the circle of fifths and found out that it is a system of arrangement of all keys, taking into account the degree of their relationship. Thanks to anharmonicity in music, the circle closes, forming sharp and flat, major and minor keys. Knowing the principle of the system, you can easily build any chords and find out the number of accidentals in harmony.