A Major Triad
Chord Tones: A Major Triad
Symbol: M, maj, (none) — Formula: 1-3-5
| Degree | Note | Frequency (A=440, Equal) |
|---|---|---|
| 1 | A | 440.000 Hz |
| 3 | C# | 277.183 Hz |
| 5 | E | 329.628 Hz |
Chord Notation
| Notation Type | Symbol / Value |
|---|---|
| Lead Sheet Symbol | AM |
| All Common Symbols | M, maj, (none) |
| Interval Formula | 1-3-5 |
| Harmonic Category | consonant |
Roman numeral (e.g. I, IV, V) and Nashville Number notation are key-dependent. See Keys pages for chord function within specific keys.
Inversions
| Inversion | Notes (low to high) | Bass Note | Slash Notation |
|---|---|---|---|
| Root Position | A – C# – E | A | A Major Triad |
| First Inversion | C# – E – A | C# | A Major Triad/C# |
| Second Inversion | E – A – C# | E | A Major Triad/E |
Harmonic Function
The A major chord commonly functions as the submediant (vi) in C major or dominant (V) in D major. Its harmonic role varies by key — in major keys it provides stable harmonic grounding.
The major triad is the most fundamental chord in Western music, built from the root, major third, and perfect fifth. It has a bright, stable, and resolved sound.
Common Progressions
The A Major Triad frequently appears in these progression patterns (shown in Roman numeral notation relative to key):
I-IV-V-II-V-vi-IV
Songs Featuring the Major Triad
Well-known songs where the A Major Triad — or this chord type — plays a prominent role:
- Let It Be – Beatles
- Don't Stop Believin' – Journey
- Imagine – John Lennon
Tuning Frequencies Across Temperaments
Frequencies shown at A=440 Hz. View full temperament data for any note.
| Note | Equal Temp. | Pythagorean | Just Intonation |
|---|---|---|---|
| A | 440.000 Hz | 440.000 Hz | 436.043 Hz |
| C# | 277.183 Hz | 278.437 Hz | 279.067 Hz |
| E | 329.628 Hz | 330.001 Hz | 327.032 Hz |
Scales Containing the A Major Triad
These scales include the A Major Triad as a diatonic or characteristic chord: