Tertia - it's not easy!

For those who have ever come across such a musical science as solfeggio, the notion of intervals is basic, and therefore quite understandable. However, even simple intervals conceal secrets about which a young musician can not guess. And are you interested in knowing the secrets that keep the intervals? Then go ahead! This article is about the secrets that are contained in the thirds.

Special interval

Tertia is an interval of three steps in a scale or a third stage of a key. The small third contains one and a half tones, the larger one - two. Everything, in general, is simple. But do not rush to conclusions.

In fact, it is the thirds that largely determine the character and mood of the entire musical work. It is necessary to change the large interval to a small one - and now there are shades of sadness in a light work. The secret, which is stored in a third, is called harmony. The large third serves as the basis of the major triad, the small one, respectively, forms a minor. Often, instead of triads, these parts are used, which do not give doubts about the fidelity of the works.

Non-standard thirds

In addition to large and small intervals, there are enlarged and reduced thirds. They are formed in connection with the increase or decrease of the fret steps and require mandatory resolution at clean intervals.

The enlarged third is the interval that is built on the 2nd lowered step of the fret (major or minor). In this case, the 4th stage is necessarily increased. Vv.3 is resolved into a pure tonic fifth. The interval itself sounds like a clean quarter, the difference will be visible only in the musical notation.

The reduced third is built around stable steps of the fret. Acoustically, the interval sounds just like a big second. Tertia in a smaller version should necessarily be resolved into a clean prima.

• The reduced interval of the 7th stage is constructed in natural major and harmonic minor at a lowering of the 2nd stage. This interval is always resolved into the tonic.
• Um.3 of the second stage is built on the 2nd higher level of the major and on the 2nd (clean) minor (with the lowering of the 4th stage) is allowed in the third stage.
• Um.3 increased 4th stage is constructed in harmonic major and natural harmonic minor, it is resolved in the 5th stage.

In fact, an enlarged or reduced third is an extremely rare phenomenon in music. And yet you need to know about them even for beginning musicians.

Major in minor

This feature, like the appearance of the big third in the final cadence of the minor work, became very popular among composers of the 16th-18th centuries. And entered the history of world music under the name "Picardian third". This unusual sound, first of all, gained its popularity because it was considered a symbol of the victory of good over evil, and therefore the use of the Picardian thirds breathed hope into a depressing minor sound.

The most famous classical example of the use of Picardian thirds was the "Well Tempered Clavier" by JS Bach, a collection of preludes and fugues written in all existing keys. Most of the minor fugues in this collection ends with an optimistic big third.

How to build thirds and triads

At first glance, everything seems simple and straightforward: a third is an interval of three steps. But a beginner musician can be confused by halftones, or easier - black keys. What is the starting point: the number of keys or the names of steps?

All doubts are dispelled when it comes to understanding that it is the steps of the scale that serve as the basis for constructing intervals, that is, building a large third from the note "to", should be considered as follows: "do-re-mi" - three steps. Similarly, intervals are built down. It remains only to calculate the number of tones and halftones, and it will immediately become clear with which of the threets it is necessary to deal with.

Tonic triads are built according to the following principle:

• The major triad consists of a large third at the bottom and a small top. As mentioned earlier, in order to understand the mood of a work, it is enough to have the lower large third.
• The minor triad is constructed directly opposite to the major triad: in its base there is a small third, over which there is always a large third.

In addition to the classical tonic triad quite often there are enlarged and reduced ones. It is not difficult to guess that when they are constructed, two large or, alternatively, two small thirds, which form the corresponding dissonant chord, are used simultaneously.

Music contains a lot of unsolved mysteries and mysteries. And if it seems to you that the theory is boring, try to look a little deeper, and you will understand what an amazing and mysterious world!