AP® Music Theory · Unit 6 · Topic 6.1
Passing Tones
A passing tone is a non-chord tone that fills the gap between two different chord tones by moving stepwise in one direction. It smooths a melodic or bass line that would otherwise leap.
Chords give you the skeleton of a line, but music rarely jumps from chord tone to chord tone with nothing in between. A passing tone is the note that fills that gap, stepping from one chord tone toward another without belonging to the chord itself. It falls on a weaker beat than the chord tones around it, which is why it sounds like decoration rather than harmony. The ear accepts it because it keeps moving in the same direction, step by step, so the dissonance passes through quickly instead of settling.
The defining feature is direction: a passing tone always continues on to a different chord tone than the one it left. If a third separates two chord tones, one passing tone fills the middle step. If the gap is a fourth, you need two passing tones in a row, each one a step apart, to cross the whole distance. Both still count as passing tones as long as the line keeps moving the same way until it lands on the new chord tone.
This sits right next to neighbor tones in the same unit, and the two are easy to confuse because both start on a chord tone and move by step. The test is what happens next: a passing tone keeps going to a new chord tone, while a neighbor tone steps away and comes straight back to where it started. Later topics like suspensions and sequences build on this same idea of stepwise motion connecting or decorating chord tones, so getting the direction test right here pays off throughout the unit.
Key terms
- Passing tone
- A non-chord tone that moves by step between two different chord tones in one direction.
- Chord tone
- A note that belongs to the current harmony, such as the root, third, or fifth.
- Neighbor tone
- A non-chord tone that steps away from a chord tone and returns to that same chord tone.
- Non-chord tone
- Any note in a melody or bass line that is not part of the underlying chord.
- Stepwise motion
- Movement from one note to an adjacent note in the scale, as opposed to a leap.
Watch it explained
- How it worksHow does a passing tone move by step in one direction from one chord tone to the next?
- Worked exampleFind the passing tones in a bass line moving C, D, E under I and I6 in C major.
- Common mistakeWhy isn't a note between two chord tones a passing tone when the line reverses direction?
- Going furtherWhat changes when two passing tones fill in a fourth instead of one filling in a third?
Check yourself
End of topic.