6/4 Chord Function: Your Ultimate Guide 🚀

Hey there, future AP Music Theory master! Let's break down 6/4 chords and make sure you're totally confident for the exam. It's crunch time, but don't worry, we've got this! 💪

Understanding 6/4 Chords: More Than Just Inversions

Remember how we've been exploring chord functions? Well, 6/4 chords are a special case. They don't always act like their root position counterparts. A I6/4 doesn't sound very tonic, a V6/4 doesn't sound very dominant, and so on. Instead, they usually act as embellishments to existing harmonies. Think of them as musical decorations rather than structural pillars. We'll explore four types of 6/4 chords:

• Cadential 6/4
• Neighboring/Pedal 6/4
• Passing 6/4
• Arpeggiated 6/4

Cadential 6/4 Chords: The Dominant Imposter

What is it?

The cadential 6/4 is a I6/4 chord that comes right before a root position V chord, usually at a cadence. It looks like a tonic chord, but it acts like a dominant chord, briefly expanding the dominant area. We notate it as V 6–5/4–3 to show it's part of the dominant function, not an independent tonic. 💡

How does it work?

• The upper voices of the 6/4 chord move down step-wise to the V chord.
• In A Major, a I6/4 with E-A-C# moves to E-G#-B (V chord) where A goes to G# and C# goes to B.
• Double the bass (the 5th scale degree) in the 6/4 chord to emphasize its dominant function. This is a MUST for the AP exam!

Caption: Example of a cadential 6/4 chord resolving to a V chord. Notice the stepwise descending motion in the upper voices.

Resolving to the Dominant Seventh

Yes, you can resolve a cadential 6/4 to a V7! Here’s how:

• Keep the common tone (the doubled bass note) from the 6/4 chord in the V7 chord.
• Move one of the doubled bass notes down step-wise to create the 7th of the V7 chord.
• Notate this as V 8–7/6–5/4–3, indicating the stepwise movement of the upper voices.

Caption: Example of a cadential 6/4 chord resolving to a V7 chord. Notice how one of the doubled bass notes moves down to create the 7th.

Voice Leading with Cadential 6/4 Chords

• Always double the bass of the 6/4 chord. This is non-negotiable!
• Approach the 6/4 with a predominant harmony (IV or ii6). This creates a stronger sense of harmonic tension and resolution.
• Place the cadential 6/4 on a strong beat for maximum impact.
• Watch out for parallel fifths and octaves, especially since the upper voices move in parallel motion.

Caption: Examples of cadential 6/4 chords resolving to V and V7 chords. Note the doubled bass and stepwise motion.

Neighboring or Pedal 6/4 Chords: The Embellisher

These 6/4 chords embellish the top lines of a piece. The bass note stays the same (like a pedal tone), while the upper voices briefly change and then return. For example, a I-IV6/4-I progression in C Major has a constant C in the bass, while the upper notes move to create the IV6/4 chord and then return to the I chord.

Passing 6/4 Chords: The Connector

Passing 6/4 chords occur when the bass line moves up or down, usually by a third. The 6/4 chord fills in this skip, creating a stepwise motion in the bass. For example, in a I-V6/4-I6 progression in C Major, the bass line moves C-D-E, with the V6/4 filling the gap between C and E.

Arpeggiated 6/4 Chords: The Same Chord, Different Bass

Arpeggiated 6/4 chords embellish the same triad by changing the bass note. For example, a I-I6-I6/4 progression uses inversions of the tonic chord to create a more interesting bass line. The 6/4 chord has the same function as the other inversions but is used for embellishment rather than harmonic change.

Final Exam Focus 🎯

Okay, let's get down to brass tacks. Here's what you really need to nail for the AP exam:

• Cadential 6/4 chords: Know their function, voice leading rules (especially doubling the bass), and notation (V 6–5/4–3 or V 8-7/6-5/4-3).
• Distinguish between different types of 6/4 chords: Understand the context for cadential, neighboring, passing, and arpeggiated 6/4 chords.
• Voice Leading: Pay attention to stepwise motion, common tones, and avoiding parallel fifths and octaves.
• Predominant Harmonies: Remember that cadential 6/4 chords are best preceded by a predominant harmony.

Cadential 6/4 chords are a frequent topic on the AP exam, so make sure you understand them thoroughly.

Last-Minute Tips

• Time Management: Don't spend too long on any one question. If you're stuck, move on and come back later.
• Double-Check: Always double-check your voice leading, especially for parallel fifths and octaves.
• Read Carefully: Make sure you understand what the question is asking before you start writing.
• Stay Calm: You've got this! Take deep breaths and trust your preparation.

Practice Question

Multiple Choice Questions

1. In a cadential 6/4 chord, which note of the chord should always be doubled? (A) The root (B) The third (C) The fifth (D) The seventh

2. A cadential 6/4 chord typically resolves to which chord? (A) I (B) ii (C) IV (D) V

3. Which type of 6/4 chord involves a bass line that remains stationary while the upper voices move? (A) Passing 6/4 (B) Arpeggiating 6/4 (C) Neighboring/Pedal 6/4 (D) Cadential 6/4

Free Response Question

Compose a four-part harmonization for the following melody in C major. Include a cadential 6/4 chord before the final cadence. Provide a Roman numeral analysis below the staff.

[Image of a four-bar melody in C major with the following notes: G4-A4-G4-E4 | F4-G4-F4-D4 | E4-F4-E4-C5 | B4-C5-B4-G4]

Scoring Breakdown:

• Melody: (1 point) Correctly notated melody.
• Harmony: (4 points) Correctly harmonized the melody using appropriate chords, including a cadential 6/4 chord before the final cadence. Correct Roman numeral analysis.
  • 1 point for correct use of predominant harmony before the cadential 6/4
  • 1 point for correct cadential 6/4 chord (doubled bass, correct notes)
  • 1 point for correct V chord following the cadential 6/4
  • 1 point for correct final I chord
• Voice Leading: (3 points) Correct voice leading throughout the progression, including:
  • 1 point for no parallel fifths or octaves
  • 1 point for smooth voice leading (stepwise motion where possible)
  • 1 point for correct resolution of the cadential 6/4 to the dominant

Answer Key

Multiple Choice:

1. (C)
2. (D)
3. (C) Free Response Question:

• Melody: (1 point) The melody is correctly written.
• Harmony: (4 points)
  • Measure 1: I
  • Measure 2: ii6
  • Measure 3: V 6-5/4-3
  • Measure 4: I
• Voice Leading: (3 points)
  • No parallel fifths or octaves present.
  • Voices move smoothly, with stepwise motion.
  • Cadential 6/4 resolves correctly to the dominant.

(Note: There may be multiple correct answers for the FRQ, this is just one example)

Alright, you've got this! Go ace that exam! 🎉