Harmonic Sequences: Your Ultimate AP Music Theory Guide 🎶

Hey there, future music master! Let's dive into harmonic sequences, a crucial topic for your AP Music Theory exam. Think of this as your go-to resource for a quick, confident review. Let's get started!

What are Harmonic Sequences?

Just like melodic sequences, harmonic sequences occur when a series of chords is repeated, transposed up or down by some interval. The relative motion of the chords and the voice leading are usually preserved. It's like a musical echo, but with chords! 💡

Here's a visual example:

Image via Music Theory Academy

Types of Harmonic Sequences

There are two main types:

• Descending Sequences: Each repetition of the pattern moves down by some interval. Think of it as a musical staircase going down.
• Ascending Sequences: Each repetition moves up by some interval. A musical staircase going up!

It's important to note that although the root of the chord may be ascending or descending, the actual notes may be moving in the opposite direction due to voice leading. Also, a sequence descending by fifths is the same as a sequence ascending by fourths and vice versa. The same is true for thirds and sixths.

Characterizing Harmonic Sequences

When describing a sequence, focus on fifths, thirds, or seconds. The most common types are:

• Descending Fifths
• Descending Thirds
• Ascending Seconds

If you see a sequence ascending by sixths, interpret it as descending by thirds. If you see a sequence descending by fourths, interpret it as ascending by fifths. Also, consider the melodic line: if the melody is primarily ascending, the sequence is likely ascending, and vice versa.

Fonte, Ponte, and Monte: The Emotional Arc of Sequences

These Italian terms describe the direction and function of harmonic sequences:

Monte (Mountain) ⛰️

• Meaning: Ascending harmonic sequence.
• Function: Builds tension, often leading to a climax.
• Characteristics: Melodies often ascend, typically accompanied by a crescendo and more complex embellishments.
• Example: Beethoven's Symphony No. 5 (first movement), Chopin's Prelude Op. 28 No. 15

Fonte (Fountain) ⛲

• Meaning: Descending harmonic sequence.
• Function: Creates a sense of resolution and stability.
• Characteristics: Melodies often descend, typically used to decrease tension and drama.
• Example: Mozart's Symphony No. 40 (first movement), Bach's Brandenburg Concerto No. 3

Ponte (Bridge) 🌉

• Meaning: A harmonic sequence that is neither ascending nor descending, often delaying resolution.
• Function: Increases tension by delaying a cadence, typically found in the dominant section.
• Characteristics: Often "stands" on the dominant tone and lacks a cadence.
• Example: Debussy's Prelude "La fille aux cheveux de lin