Interval comes from latin Intervalum and mention the distance or the space that there is from one place to another or from one time to another. For example: “Between the two meetings, I have an interval of two hours that I can use to go to visit Uncle Ramón”, "I'm going to see the doctor's agenda to see if he has any interval to assist you", “On this route there is a service station at an interval of every fifty kilometers”, "Animals usually appear at intervals of a few meters".
In the field of music , interval is the difference in height between sounds of two notes. He musical interval It can be measured in degrees or tones and expressed in a simple arithmetic ratio.
There are different types of musical intervals: tonal, modal, augmented, diminished, simple, compound, harmonic, melodic or complementary, among others. Each type depends on the characteristics of the sounds in question.
On the one hand there are intervals tonal, which may have only a fair value: first (also known as unison), fourth, fifth and eighth. The manners, on the other hand, they can be major or minor, and they are the remaining ones: second, third, sixth and seventh. In both cases, the intervals can be increased and decreased (for example: taking the fourth of DO natural to natural FA, increasing it would reach sustained FA).
Another classification separates the intervals into simple (those that do not extend for more than one octave) and compounds (those who do overcome it). It should be mentioned that the compound intervals have the same properties that the corresponding simple if an octave is subtracted; For example, since a tenth is a third to the eighth, it is considered tonal and may be greater or lesser, while a twelfth exceeds the octave by a fifth, so it should be treated as a tonal interval.
With respect to the interpretation of an interval, to its execution in a instrument, is considered melodic when the notes that compose it are played separately, successively, and harmonic If they should sound at the same time. The first type is clearly seen in an arpeggio and the second, in a chord in which all sounds are produced simultaneously.
Finally, it is known as intervals complementary to those who form an octave when combined, as is the case with a third and a sixth; It is important to highlight that at first sight the sum gives nine, because the first grade of the sixth is the last of the third, which gives us a note "duplicate" (a third from DO to MI plus a sixth from MI to DO).
An interval can also be a set of values adopted by a magnitude between two limits . In this sense, we can talk about frequency range or temperature range .
At theater, interval is a period of dead time in the middle of the development of a work . These lapses usually appear in works of very long duration, so that the spectators can take advantage of the rest and go to the bathroom, buy some candy, etc .: "I hope the interval comes soon: I'm very thirsty and I want to buy a soda.", "The intensity of the work falls after the interval", “I got bored during the interval, which lasted for more than half an hour”.
The intervals of a play also serve to assimilate the history, to reflect on the experiences lived in the last act or events and try to anticipate what will come. For many people, these pauses benefit the impact of the functions, since they renew them at the beginning of each act, generating in the public a series of sensations that keep them immersed in fiction.