#AP Music Theory: Diatonic Chords & Progressions - The Night Before 🎶

Hey there, future music maestro! Let's get you feeling confident and ready to rock the AP Music Theory exam. We're going to break down diatonic chords and progressions so they feel like second nature. Think of this as your ultimate cheat sheet – all killer, no filler! Let's dive in!

#1. Diatonic Chords: The Building Blocks

#What are Diatonic Chords?

Diatonic means "within the key." Diatonic chords are built using only the notes of a specific scale. Think of them as the 'home team' for a key. 🏡
In any key, these chords can be major, minor, diminished, or (rarely) augmented. The quality of the chord depends on the intervals between the notes.

Key Concept

Remember: Diatonic chords are the foundation of harmony in tonal music. Understanding them is crucial for both multiple-choice and free-response questions.

#Diatonic Chords in Major Keys

There are seven diatonic chords in a major scale, each built on a different scale degree.
We use Roman numerals to identify these chords. Uppercase for major, lowercase for minor, and a ° symbol for diminished.

Memory Aid

Major keys have Major chords on I, IV, and V. All others are minor except for the vii°.

Here's the breakdown in any major key:
- I - Tonic (Major)
- ii - Supertonic (minor)
- iii - Mediant (minor)
- IV - Subdominant (Major)
- V - Dominant (Major)
- vi - Submediant (minor)
- vii° - Leading Tone (diminished)

#Example: C Major

Let's visualize this in C Major:

C Major Scale

Building triads on each scale degree:

C Major Triads

And finally, identifying the chord qualities:

C Major Chord Qualities

Quick Fact

The pattern of chord qualities (Major, minor, diminished) is the same for all major keys!

Exam Tip

Always double-check your Roman numerals! Uppercase = Major, lowercase = minor, ° = diminished.

#Diatonic Chords in Minor Keys

Minor keys have a different pattern of chord qualities.
The harmonic minor scale is often used to create the V (dominant) chord as a major chord. This is done by raising the 7th scale degree by a half step.

Memory Aid

In minor, think minor on i and iv, Major on III, V, and VI (with the V often altered), and diminished on ii° and vii°.

Here's the breakdown in any minor key (using harmonic minor for V and vii°):
- i - Tonic (minor)
- ii° - Supertonic (diminished)
- III - Mediant (Major)
- iv - Subdominant (minor)
- V - Dominant (Major)
- VI - Submediant (Major)
- vii° - Leading Tone (diminished)

#Example: G Minor

Let's see this in G minor:

G Minor Scale

Building triads on each scale degree:

G Minor Triads

Identifying chord qualities (note the raised 7th for V):

G Minor Chord Qualities

Common Mistake

Don't forget that the V chord in minor is usually a major chord (using the raised 7th of the harmonic minor scale). This is a common point of confusion!

#Scale Degree Names

It's also helpful to know the names of the scale degrees:

Degree	Name	Major	Minor
1	Tonic	I	i
2	Supertonic	ii	ii°
3	Mediant	iii	III
4	Subdominant	IV	iv
5	Dominant	V	V
6	Submediant	vi	VI
7	Leading Tone	vii°	vii°

Scale Degree Chart

Quick Fact

No naturally occurring augmented chords in diatonic scales! They must be altered.

#🦜 Polly Wants a Cracker 🦜

Okay, quick check! Can you spell all the diatonic triads in B Major? (B, C#m, D#m, E, F#, G#m, A#dim) How do you spell a dominant chord in A Major? (E, G#, B)

Practice Question

Multiple Choice:

In the key of E minor, what is the quality of the subdominant chord? a) Major b) minor c) diminished d) augmented
Which Roman numeral represents the leading-tone chord in a major key? a) V b) vi c) vii° d) IV

Free Response:

Given the following chord progression in C minor: i - iv - V - i

a) Identify the quality of each chord (minor, Major, diminished).
b) Write out each chord in root position, using accidentals as needed.
c) Explain the function of the V chord in this progression.

Answer Key

Multiple Choice:

b) minor
c) vii°

Free Response

a) i (minor), iv (minor), V (Major), i (minor) b) i: C Eb G, iv: F Ab C, V: G B D, i: C Eb G c) The V chord (G Major) is the dominant, which creates tension and pulls strongly towards the tonic (C minor), providing a sense of resolution.

#2. Chord Progressions and Harmonies

#What are Chord Progressions?

Chord progressions are sequences of chords that create a sense of motion and direction in music. Think of them as the 'sentences' of music. 🎼
They are the backbone of musical structure, creating mood and emotion.

#Common Chord Progressions

Tonic-Dominant (I-V): Creates a sense of stability and resolution. Like coming home after a long trip. 🏠
I-IV-V: A very common progression, creating motion and momentum. Think of it as a musical 'walk'.🚶

Memory Aid

I-IV-V is like a musical '1-2-3' – simple, versatile, and foundational.

#Complex Progressions

Composers use more complex progressions, inversions, and dissonant chords to create tension and interest.
Dissonant chords create tension, which is then resolved by consonant chords.

Exam Tip

Listen carefully to how chord progressions create different feelings in music. This will help you analyze and understand musical structure.

Practice Question

Multiple Choice:

Which of the following is a common function of the dominant chord? a) To provide a sense of stability b) To create tension and lead to the tonic c) To act as a passing chord d) To create a sense of finality
The progression I-IV-V is most similar to which other musical form? a) Fugue b) Sonata c) 12-bar blues d) Rondo

Free Response:

Analyze the following chord progression in F Major: I - vi - IV - V - I

a) Identify the quality of each chord (Major, minor, diminished).
b) Explain the function of the vi chord in this progression.
c) Describe the overall effect of this progression.

Answer Key

Multiple Choice:

b) To create tension and lead to the tonic
c) 12-bar blues

Free Response

a) I (Major), vi (minor), IV (Major), V (Major), I (Major) b) The vi chord (d minor) acts as a submediant, adding color and a slight detour before moving to the subdominant. c) The progression starts with stability, moves through a brief detour (vi), then builds tension with the IV and V chords before resolving back to the tonic, creating a satisfying sense of closure.

#Final Exam Focus 🎯

#High-Priority Topics

Diatonic Chords: Know your major and minor chord qualities inside and out! This is the foundation of everything. 🧱
Roman Numeral Analysis: Be able to identify chords and their functions using Roman numerals. Practice, practice, practice! ✍️
Chord Progressions: Understand basic progressions like I-V and I-IV-V, and how they create musical tension and release.

#Common Question Types

Multiple Choice: Expect questions on chord qualities, Roman numeral analysis, and scale degree names.
Free Response: Be prepared to analyze chord progressions, identify non-diatonic chords, and write short passages using diatonic harmony.

#Last-Minute Tips

Time Management: Don't get bogged down on one question. If you're stuck, move on and come back later. ⏰
Double-Check: Always double-check your Roman numerals, chord qualities, and accidentals. Small mistakes can cost you points. 👀
Trust Your Ear: If something doesn't sound right, it probably isn't. Use your musical instincts to guide you. 👂
Stay Calm: Take deep breaths, and remember you've got this! You've worked hard, and now it's time to show off your skills. 💪

Alright, you've got this! Go get 'em, and make some beautiful music! 🎉