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Writer's pictureOlive Ghosh

Scales, Tonality and Key

Performers often practice scales to develop their technique. The collections of pitches and recurring patterns performers use to focus attention on technical aspects are the same building blocks of musical composition.


Scale

A scale is a collection of pitches in ascending and descending order. Musicians use a scale as a convenient way of displaying the notes used in a melody or harmony.

In this Figure by Haydn, the melody consists of 24 notes but only seven different letter names.


Pitch Class

A pitch class contains all notes of the same name regardless of octave. The caret (ˆ) above each number indicates that the number represents a scale degree.


The pitch classes for the melody in this Figure are arranged in ascending order to form a scale. The caret (ˆ) above each number indicates that the number represents a scale degree.

Although an infinite variety of pitch combinations is available, the following scales represent those in most common use during the past 200 years.


Diatonic Scales

Diatonic (literally “across the tones”) defines a scale of mixed half and whole steps (and an occasional step and a half) in which each individual tone plays a role. The first tone of a scale, the tonic, is a point of rest and is considered to be the most stable. Other tones lead toward or away from it, creating varying degrees of tension or relaxation. Since the tonic is the focal point of the scale, the most stable note, and the point of greatest relaxation, diatonic melodies frequently end on the tonic note. At times the word diatonic is used to indicate a tone that is part of a particular scale pattern—as distinguished from a nondiatonic tone that does not belong to the scale pattern.


Scale Degree names

Scale Degree Names

Two different scales are shown to illustrate the application of scale degree names to diatonic tones.

Major Scale

The major scale is a scale of seven different pitch classes with whole steps separating adjacent tones, except for half steps between the third and fourth degrees and between the seventh and eighth (or first) degrees. The eighth pitch has the same letter name as the first and thus is treated as a duplication.

C Major Scale


Key Signature


The arrangement of the necessary sharps or flats is called a key signature and appears at the beginning of each staff in a composition after the clef. Notice that each successive tonic, or beginning note, is five scale degrees (called a perfect fifth) above or four scale degrees below the previous tonic. A new sharp is added to the key signature for each ascending perfect fifth (P5); in the flat signatures, a flat is dropped for each ascending P5.

Key Signature

Key Signature

Minor Scale


The minor scale is another common diatonic scale. It is more varied in pitch material because there are two different versions of both the sixth and seventh scale degrees. Traditionally, the minor scales have been described as having three distinct forms, but in practice, composers use all the scale resources of the minor scale within a single composition. The three traditional forms of the minor scale are called natural, harmonic, and melodic.


Natural Minor Scale

A Natural Minor Scale

The natural minor scale can be thought of as a major scale from the sixth to the sixth degree.


Relative Relationship
Harmonic Minor Scale

The harmonic minor scale has a raised seventh degree. The added impetus of a raised seventh degree gives more melodic thrust toward the tonic. Raising the seventh degree creates a step and a half between the sixth and seventh degrees, and a half step between the seventh and eighth degrees. Accidentals used to raise the seventh degree do not appear in the key signature.

A Harmonic Minor Scale

The Mozart excerpt in Figure below utilizes the harmonic minor scale. Notice the presence of G-sharps in every measure except 5 and 6.

The Mozart excerpt utilizes the harmonic minor scale. Notice the presence of G-sharps in every measure except 5 and 6.
Melodic Minor Scale

(discussion continued in classes)




Circle of Fifths

Another way to visualize the relationship between the major scales and their relative minors is with the circle of fifths. All of the key signatures are given within the circle. The major scale tonics are listed outside the perimeter of the circle. The relative minors appear within the inner circle. Circle of Fourths is just the opposite of circle of fifths in anti-clockwise direction, but both determines the same.



Parallel Relationship


A major and a minor scale that begin on the same tonic note are said to be in parallel relationship. Figure below shows the major scales and their parallel minors.

Tonality


Tonality refers to an organized system of tones (e.g., the tones of a major or minor scale) in which one tone (the tonic) becomes the central point to which the remaining tones are related. In tonality, the tonic (tonal center) is the tone of complete relaxation, the target toward which other tones lead.


Key


The term key refers to the tonal system based on the major and minor scales. This system is by far the most common tonal system, but tonality can be present in music not based on the major and minor scales.


Pentatonic Scale


A pentatonic scale is not considered diatonic because it is not based on the same two-step formula that major scales are based on. Pentatonic scales do not contain half steps. However, the notes contained in pentatonic scales can be considered diatonic to a key when the same notes are found in the parent major scale.


Non diatonic Scales


A scale that does not observe the interval sequence of the diatonic or pentatonic scales is called a nondiatonic scale. Many nondiatonic scales have no identifiable tonic.


Chromatic Scale

A chromatic scale is a nondiatonic scale consisting entirely of half-step intervals. Since each tone of the scale is equidistant from the next, it has no tonic.

Whole tone scale

A whole-tone scale is a six-tone scale made up entirely of whole steps between adjacent scale degrees.


Blues Scale

The blues scale is a chromatic variant of the major scale with flat third and flat seventh. These notes, alternating with the normal third and seventh scale degrees, create the blues inflection. These “blue notes” represent the influence of African scales on this music.

Non-Western Scales

Other cultures have many scales that are not diatonic. Figure below shows one of the thaats, or seven-note scales, of northern Indian music.


Octatonic or Diminished Scale

The octatonic scale is an eight-note scale composed of alternating whole steps and half steps. Jazz musicians refer to this scale as diminished because the chords resulting from this scale’s pitches are diminished.


Nontraditional Scales

A number of nontraditional scales occur occasionally in the music of the late nineteenth and twentieth centuries. Most of these scales are made of a symmetrical pattern of intervals.



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Prasenjit
Prasenjit
27 juin 2023
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Thank you Nmag India❤️

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Shubham Gupta
Shubham Gupta
27 juin 2023
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Helpful.

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