C major and C natural minor share a tonic
C major contains C, D, E, F, G, A and B. C natural minor contains C, D, Eb, F, G, Ab and Bb. Both begin on C, but the natural minor scale has a lowered third, sixth and seventh relative to major. These are parallel major and minor scales because they share a tonic.
Above a held C, E and Eb make different relationships with the same bass. The same applies to A and Ab. Keeping the instrument, register and loudness constant makes these pitch differences easier to distinguish from the character of a preset or performance.
| Scale degree | C major | C natural minor |
|---|---|---|
| 1 | C | C |
| 2 | D | D |
| 3 | E | Eb |
| 4 | F | F |
| 5 | G | G |
| 6 | A | Ab |
| 7 | B | Bb |
One note changes the quality of a triad
From the root, a major triad places its third four semitones higher and its fifth seven semitones higher. A minor triad places its third three semitones above the root while keeping the same seven-semitone fifth. The starting pitch is counted as zero.
Lowering E to Eb in C–E–G changes C major to C minor. Moving all three notes down by the same distance instead would transpose the chord while preserving its major quality. A change of chord quality and a change of pitch level are therefore separate operations.
C major and A minor share notes
A natural minor uses A, B, C, D, E, F and G. That is the same collection as C major, starting from A. They are relative scales. In a piece of music, the bass, chord movement, melodic emphasis and phrase endings help establish whether C or A feels like home.
The chord sequences C–F–G–C and Am–Dm–Em–Am both use the white-note collection, but return to different home chords. Merely selecting C major or A minor in a DAW does not establish that musical centre for the listener. The written parts have to create the relationship.
Major and minor do not prescribe a single mood
Major is often introduced as happy and minor as sad. Those descriptions can help someone remember an early example, but they are not reliable rules for writing. Tempo, rhythm, register, melody, sound and musical context all contribute to how a passage feels.
A quiet major chord with a slow melody can feel reflective. A fast minor-key riff can feel energetic. The emotional impression belongs to the complete passage, so a producer has many ways to alter it without changing the key or replacing every chord.
Natural minor is a starting point
Minor-key music does not always stay inside natural minor. Raising its seventh produces the harmonic minor scale: A, B, C, D, E, F, G#. In A minor, G# is also the third of an E-major chord. The move from E major to A minor lets G# approach A by a semitone.
The distinction matters when a minor-key track contains a note outside its natural-minor scale. That note may serve a clear harmonic purpose. A scale is a useful description of a collection, while an actual piece can draw on altered notes for particular chords and phrases.