Interval Inversion
To invert an interval means moving the lowest note an octave higher. The higher note becomes the lower and the lower note becomes the higher.
Example:
Let’s invert the interval: Diminished fifth: B – F
The inversion is: Augmented forth: F – B
When an interval is inverted:
- major intervals invert to minor intervals and minor intervals invert to major. (Major <-> Minor)
- perfect intervals invert to perfect. (Perfect <->Perfect)
- augmented intervals invert to diminished intervals and diminished intervals invert to augmented. (Augmented <->Diminished)
- the new interval is 9 minus the old interval
Triad Inversion
The lowest note is called the bass note. Triad inversion is moving the bass note an octave higher.
First inversion
First inversion means moving the root note an octave higher. The third note of the chord now becomes the bass note.
Second inversion
Second inversion moves the third note (bass note) an octave higher. The fifth note of the chord now becomes the bass note.
Seventh Chord Inversion
Same as triad inversion, the lowest note is called the bass note.
First inversion
First inversion moves the root note an octave higher. The third note of the chord becomes the bass note in first inversion.
Second inversion
Second inversion moves the third note (bass note) an octave higher. The fifth note of the chord now becomes the bass note in second inversion.
Third inversion
Third inversion moves the fifth note (bass note) an octave higher. The seventh note of the chord is now the bass note in third inversion.
If we moves the seventh note an octave higher, the chord returns to root position.
Piano Music Theory 