9a Overview - Non-chord Tones
We have already covered three of the most common types of non-chord tones (NCTs): passing tones, neighbor tones, and suspensions. In these discussions, we identified certain characteristics that we could use to classify each of the non-chord tones.
- the preparation
- type of movement used to approach the NCT
- direction from which the NCT is approached
- the non-chord tone
- must not be a member of the chord
- the resolution
- type of movement used to leave the NCT
- direction from which the NCT is left in realtion to the preparation
By describing these characteristics, we can create definitions for A passing tone (PT) is a non-chord tone which is approached by step and left by step in the same direction.
A neighbor tone (NT) is a non-chord tone which is approached by step and left by step in the opposite direction.
A suspension (SUS) is a non-chord tone which is approached by static motion and resolves downward by step.
Describing non-chord tones
This information provides a methodology and framework through which we can look at all non-chord tones, but we need further language to describe the function and characteristics of any non-chord tone.
- Accented vs unaccented
- An accented NCT occurs on a beat, and an unaccented NCT occurs on an offbeat.
- Most types of NCTs can be either accented or unaccented, but certain NCTs, such as suspensions, can only be one or the other. (For example, suspensions can only be accented.)
- Chromatic vs diatonic
- Diatonic NCTs use only the notes present in the key-signature whereas chromatic NCTs have an accidental.
- All types of NCTs can be either chromatic or diatonic, although some are extremely rare (such as a chromatic suspension).
- There are other possibilities for labeling NCTs such as ascending/descending and upper/lower. These are only applicable to certain NCTs, so it is easier to discuss these labels in those contexts.
- Passing tones can be either ascending or descending.
- Neighbor tones can be either upper or lower.