The keys that "work" with a major key are those that have a strong harmonic relationship, typically represented by the diatonic chords built on each degree of the major scale. Let's explore these relationships based on the reference provided, using A major as our example.
Understanding Diatonic Harmony in A Major
Diatonic harmony refers to the chords built using only the notes present in a specific key's scale. In the case of A major, these chords create the foundation for harmonizing melodies and creating chord progressions that sound natural within the key. Here’s a breakdown:
| Scale Degree | Function | Chord | Chord Type | Relationship to A Major |
|---|---|---|---|---|
| I | Tonic | A Major | Major | Key Center |
| II | Supertonic | B Minor | Minor | Predominant |
| III | Mediant | C-sharp Minor | Minor | Less Common |
| IV | Subdominant | D Major | Major | Predominant |
| V | Dominant | E Major | Major | Creates Tension |
| VI | Submediant | F-sharp Minor | Minor | Substitutes Tonic |
| VII | Leading Tone | G-sharp Dim. | Diminished | Strong Resolution |
Common Chord Progressions
The chords above are often used in various chord progressions. Some common progressions in A major are:
- I-IV-V (A-D-E): A fundamental progression in Western music.
- I-V-vi-IV (A-E-F#m-D): A popular progression often found in pop music.
- ii-V-I (Bm-E-A): A jazzy progression that creates smooth voice leading.
Examples and Practical Insights
- Tonic (A Major): The starting and ending point, providing stability. It resolves the tension built by other chords.
- Supertonic (B Minor): Often leads to the dominant (E Major) or tonic (A Major).
- Subdominant (D Major): Creates movement away from the tonic and towards the dominant.
- Dominant (E Major): Creates strong tension, urging resolution back to the tonic.
- Submediant (F-sharp minor): Can substitute for the tonic chord, adding color and variety.
- Leading-tone (G-sharp Diminished): Due to containing notes close to A, G# diminished chord creates a very strong pull to A, making it an exceptional chord to resolve to tonic A Major.
Importance of Chord Quality
The chord quality (major, minor, or diminished) is crucial for establishing the tonality. Major chords typically create a bright, happy sound, while minor chords can sound sad or introspective. The diminished chord is dissonant and unstable, creating a strong desire to resolve.
