As a musicologist with a passion for the intricacies of musical theory, I take great pleasure in unraveling the complexities of harmony and its role in shaping the emotional landscape of music. Today, we're going to delve into the concept of the secondary dominant, a fascinating subject that is fundamental to the understanding of harmonic progressions in Western music.
The secondary dominant is a type of dominant seventh chord that serves as the dominant of a chord other than the tonic. To grasp this concept, it's crucial to first understand the basic structure of chords in a key. In any given key, the tonic is the home chord, the I chord, which is the foundation upon which the key is built. The dominant, or the V chord, is the chord that creates a sense of tension and a need to resolve back to the tonic.
Now, when we speak of a secondary dominant, we are referring to a dominant seventh chord that is not the dominant of the tonic but rather the dominant of another chord within the key. This means that it is a chord that leads to a chord other than the final chord of the key (the tonic). For example, in the key of C major, the V chord is G7. If we were to create a dominant seventh chord on the note E, which is the third note of the C major scale, we would get an E7 chord. This E7 chord would act as a dominant to the A minor chord (A minor being the vi chord in the key of C major). So, in this case, E7 is a secondary dominant of A minor.
The function of a secondary dominant is to create a pivot or a bridge to another chord. It leads the harmony in a new direction, often to a chord that is a fifth away from the secondary dominant itself. This is known as a pivot chord. The use of secondary dominants is a common technique in classical music, jazz, and popular music, adding richness and depth to the harmonic structure.
Let's explore this with a more detailed example. In the key of C major, if we want to lead to the vi chord (A minor), we can use E7 as a secondary dominant. The E7 chord contains the notes E, G#, B, and D, which are the root, major third, perfect fifth, and minor seventh of the E7 chord, respectively. The G# in the E7 chord creates a leading tone to the A note, which is the root of the A minor chord. This leading tone is what gives the secondary dominant its characteristic pull towards the chord it is dominating.
The resolution of a secondary dominant is similar to that of a regular dominant. The dominant seventh chord (in this case, the secondary dominant) resolves to the chord it is a dominant of, with the seventh of the chord typically resolving down by half step and the third of the chord resolving up by half step, creating a smooth and satisfying resolution.
Secondary dominants can also be used to create a deceptive resolution, where the chord does not resolve to the expected chord but instead to another chord, often a half step away. This can add an element of surprise and keeps the listener engaged.
In jazz, the use of secondary dominants is particularly prevalent. Musicians often use them to create more complex and interesting improvisational lines. For instance, a saxophonist might use a secondary dominant to lead into a new section of a solo, or a pianist might use one to add a richer harmonic texture to an accompaniment.
In classical music, secondary dominants are often found in the works of composers like Mozart and Beethoven, where they are used to modulate to new keys or to create a sense of tension and release within a piece.
In popular music, secondary dominants are used to add harmonic interest and to create a sense of movement within a song. They can be heard in countless pop, rock, and R&B songs, often providing a moment of tension before resolving to a more stable chord.
In conclusion, the secondary dominant is a powerful tool in the harmonic palette of composers, songwriters, and musicians. It adds depth and interest to music, creating a sense of direction and movement that can be both subtle and dramatic. Understanding how to use secondary dominants can greatly enhance one's ability to appreciate and create music that is rich in harmonic content.
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A Secondary Dominant is a Dominant 7th chord that is the dominant of a diatonic chord other than the tonic. Yes I just used the word "dominant" three times. Let's see if we can clarify that a little. You'll remember from last time that in a given key the tonic is the I chord and the dominant is the V chord.Jun 18, 2012read more >>