Melodic Minor Scale and Dominant Chords in Jazz

Introduction

The melodic minor scale is a type of minor scale that includes a major seventh interval, which gives it a distinct sound when compared to traditional minor scales like the Dorian or Aeolian modes. This scale is particularly popular in jazz due to its ability to create tension and dissonance over dominant chords, resulting in unique and interesting harmonies. In this article, we will delve into the construction of the melodic minor scale, its harmonic usage, and the concept of dominant chords, as well as discussing tritone substitutions.

Construction of the Melodic Minor Scale

The melodic minor scale consists of seven notes, similar to the major scale. However, unlike the major scale, it includes a flattened third and a raised seventh interval. This combination creates an intriguing symmetrical pattern where the major and minor intervals alternate throughout the scale. For instance, a melodic minor scale starting on C would be spelled as C–D–Eb–F–G–Ab–B–C.

Harmonic Usage of the Melodic Minor Scale

When applied over dominant chords, melodic minor scales can create tension due to the presence of dissonant intervals, particularly the major seventh interval. Over a C7 chord, for example, using a D melodic minor scale would create a G Lydian Dominant sound. The use of melodic minor scales over dominant chords allows musicians to add color and complexity to their solos and improvisations.

Dominant Chords and Their Relationship to Melodic Minor Scales

Dominant chords are chords built off the fifth degree of a major scale. In the context of the melodic minor scale, dominant chords can be created by extending the scale to include additional intervals. For example, the D melodic minor scale can be extended to include the notes D–E–F–G–A–B–C–D, forming an Am7(maj7) chord. By understanding the relationship between melodic minor scales and dominant chords, musicians can effectively incorporate these chords into their compositions and arrangements.

Tritone Substitution

Tritone substitution is a technique commonly used in jazz harmony that involves replacing a dominant chord with another chord that is a tritone away. In the context of the melodic minor scale, this could involve replacing a C7 chord with a F7 chord, as they share the same tritone (augmented fourth) interval. This substitution can create a new harmonic environment and lead to interesting harmonic developments within a composition or improvisation.

Conclusion

The melodic minor scale, with its unique combination of major and minor intervals, offers a wealth of possibilities for creating tension and complexity when applied over dominant chords. Understanding the construction of this scale, along with the principles of dominant chords and tritone substitution, opens up a vast array of harmonic choices for jazz musicians looking to push the boundaries of their craft.