Triads and Inversions

Three notes sound together. Move just the middle one a small step down, and the combined sound changes. The top and bottom notes have not moved. What changed inside the chord?

Major and minor triads can share a root and fifth while differing in their third. This lesson makes that relationship audible, then separates a chord’s root from its lowest sounding note. Allow about ten minutes. Use the staff-reading skills from the earlier lessons to check the chord spellings.

Listen inside the stack

Compare Major · together with Minor · together. Do not worry about attaching an emotion to either sound. First ask whether you can notice a difference. Then use the two “one by one” versions to find which pitch moved.

The major triad is C–E–G. The minor triad is C–E♭–G. In both, C to G spans seven semitones. What changes is C to the middle note: four semitones for E, three for E♭.

When we arrange a triad in consecutive thirds, we call its notes the root, third, and fifth. These are names for chord members. “Third” does not mean three semitones: a major third spans four semitones, while a minor third spans three. Introduction to triads

Try following just the top note in the first pair. It stays G. Then follow the lowest: it stays C. Finally attend to the changing middle. This is a useful listening habit: a whole sonority can change because one internal relationship changes.

The broken versions spread the same notes across three beats, producing an arpeggio, or broken chord. They alter the onset pattern, so compare major with minor within the same playback style. Comparing a simultaneous major chord with an arpeggiated minor chord would change two things at once.

The root is an identity; the bass is a position

It is tempting to call the lowest note “the root” every time. That works for root position, but a chord can put another member at the bottom.

Play the three arrangements below. Read the pitches from low to high and track the lowest one. The pitch classes remain C, E, and G throughout, although particular notes move to different octaves.

With C at the bottom, the chord is in root position. With E at the bottom, it is in first inversion. With G at the bottom, it is in second inversion. The root is C in all three. The chord’s overall register, spacing, and bass change, so the versions need not feel identical.

This explains chord symbols such as C/E: a C-major chord with E in the bass. It does not mean “a C note followed by an E chord.” In later listening, a bass line can move smoothly through chord inversions while the chord identity stays the same.

Transfer the construction, not the mood label

Here are two new checks. First, change F–A–C from major to minor while preserving its root and fifth. Second, name the root and bass of A–C–F, arranged from low to high.

Build it yourself, then read the stack

Use the staff-reading skill from earlier: a triad in root position skips alternate letter positions. Choose F major, change only its quality to minor, then put its third in the bass. Predict both the written notes and the lowest note before playing.

For that sequence, F–A–C becomes F–A♭–C, then A♭–C–F. The flat belongs to A, not to the neighboring line: the third's spelling remains visible. Try D minor next and explain why its third is F rather than F♭.

When you hear a chord change in a song, ask whether the bass moved, whether an upper note moved, or whether both did. You may not be able to name every note yet. Even hearing that distinction prepares you to understand how a melody interacts with the harmony beneath it—the subject of the next lesson.