'HARMONY
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HARMONY
Besides the simultaneous conception of relations, each chord of the series in Example 5 clearly expresses a definite chord relation or harmony. The first chord expresses the idea of harmonic center, harmonic point of unity, and is called the tonic harmony. The second chord expresses the idea of harmonic progression to the tonic harmony, and is called the dominant harmony. The third chord is tonic. The fourth expresses progression through the dominant (fifth chord) to the tonic harmony, and is called the subdominant harmony. Tonic is represented by I, dominant by V, subdominant by IV.
It is plain from this that melody expresses two distinct conceptions of relationships or harmony: first, those relationships constituting the unity of the simultaneous grouping of tones, called, in general, chords, as we have seen; and secondly, those relations constituting the larger unity of progressive groupings of chords, called, in general, tonality. Chord and tonality are, therefore, distinctly harmonic ideas.
These three harmonies and their chords express not only a general but a specific idea of tonality, called diatonic tonality, and is illustrated in the following example:
EXAMPLE 6
Besides the three harmonies, diatonic tonality involves seven melodic incidents: I» 3> 5 = tonic chord; 5, 7, 2 = dominant chord; 4, 6, i = subdominant chord. Chord also involves the harmonic unit called interval—the relation of any two of these melodic incidents. These are called primes, seconds, thirds, etc., according to the number of degrees involved.
In the following example:
EXAMPLE 7
besides the tonic, subdominant and dominant harmonies, called primary harmonies, the second, third and fifth chords present three new harmonic ideas called, respectively, mediant, with its chord, e, g, b; submediant, with its chord, a, c, e; and supertonic, with its chord, d, f, a. These are designated as secondary harmonies.
Each tone in the chord-groups of the following example:
EXAMPLE 8
although in a different order of grouping, expresses essentially the same idea of relationship. F is felt to be the basic incident, called root, and defined as such by the tone c, called fifth. This root-defining nature of c becomes apparent if we substitute b (the line under the letter stands for a flat), in which case / no longer appears as the basic incident or root. The remaining incident of the chord is a variable element, illustrated in Example 9: EXAMPLE 9
•; -*- I
The tone a in Example 8 expresses a relatively bright color, called the major mode; a, in Example 9, a dark color, called the minor mode. This color incident of the chord is called the third. Chord, therefore, is a harmonic unity involving root, third and fifth, and named by the root-tone, i. e., chords of a, b, etc. Applying this dual nature of the chord to Example 6, substituting the minor for the major mode of the tonic and subdominant chords, as follows,
EXAMPLE 10
J_
J_
- I IV V I
no change is apparent in the harmonic character of each chord; the first chord is still tonic, the second chord subdominant, the third chord dominant. All that has been changed is the character, the mode of the tonic and subdominant chords. In the following example: EXAMPLE n
N. B.
we find a change, also, in the mode of the dominant (N. B.) chord. This change of the mode of the chord (N. B.) does not affect its dominant character. The inclu-
- Minor chords are represented by small numerals.
