Understanding the Practice of Ascending and Descending Melodic Minor Scales

The melodic minor scale is a fascinating concept in music theory that has been deeply ingrained in Western classical and jazz traditions. One of the most intriguing aspects of this scale is its different practices when ascending and descending, which are rooted in historical convention and musical context.

Ascending Melodic Minor Scale

When ascending the melodic minor scale, a common practice is to raise the 6th and 7th degrees compared to the natural minor scale. This is often notated as follows in C melodic minor:

Ascending:

C D E F G A# B# C 1 2 3 4 5 6 7 8

The raised 6th and 7th degrees (A# and B#) in C melodic minor create a stronger leading tone effect, leading smoothly to the tonic note (the root of the scale). This alteration is particularly useful in melodic contexts such as in jazz or classical music, where the leading tone creates tension that resolves to the tonic. The use of a raised 6th and 7th in the ascending melodic minor scale is a technique that adds color and brilliance to the music, enhancing its melodic and harmonic richness.

Descending Melodic Minor Scale

When descending the melodic minor scale, it is typically played like the natural minor scale, which includes the lowered 3rd, 6th, and 7th degrees. For C melodic minor descending, it is:

C B A G F E D C 1 7 6 5 4 3 2 1

This practice emphasizes a more stable and consonant sound when descending, which is often preferred in melodic lines. The natural minor sound is generally more comfortable and familiar in descending passages, providing a sense of resolution. The descending melodic minor scale, with its familiar minor sound, can effectively end melodic phrases on a more stable note, making it easier for listeners to recognize and appreciate the musical phrase's resolution and coherence.

Historical Context and Compositional Choices

While the practice of playing melodic minor scales differently when ascending and descending is a common guideline, it is not strictly a rule. Composers throughout history have used this technique to great effect, blending the tension and resolution of the ascending melodic minor scale with the stability and familiarity of the descending natural minor scale.

A notable example is Bach's Bouree in E minor. In the "A" section of this piece, Bach uses melodic minor to climb back to the E, and then the scale descends in natural minor. Despite the mixed use of these scales, the piece remains one of the coolest melodies in minor. This demonstrates that using just one scale isn't inherently more modern or sophisticated; the effectiveness of the composition lies in how these techniques are employed.

Another example is Bach's Presto from the B minor Partita for Solo Violin. This piece starts in natural minor and then ascends in melodic minor to reach the V7 chord (F7), after which the scale descends naturally. There are numerous other examples where the reverse technique is used, such as ascending in natural minor and descending in melodic minor. These examples show the fluidity and versatility of the melodic minor scale in different compositional contexts.

Ultimately, the practice of ascending and descending melodic minor scales is a guideline that allows musicians to exploit the unique characteristics of the scale while maintaining a sense of musical coherence. Whether a piece starts with a tense and colorful ascent or a familiar and stable descent, the key is in how these techniques are used to enhance the overall musical composition.