An inversion is a chord whose notes have been reordered so that something other than the root is the lowest note. For a C chord made of C, E, and G, both E-G-C with E in the bass and G-C-E with G in the bass are inversions. The root note that gives the chord its name is still C, but the sound and the movement of the bass line change.
Why use inversions?
When the low note jumps too far in a chord progression, inversions let you connect to a neighboring note smoothly. With the same progression, the bass movement becomes smoother and the accompaniment sounds like it flows naturally.
The basic types
For a triad there is root position, with the root at the bottom, first inversion, with the third at the bottom, and second inversion, with the fifth at the bottom. The chord tones are the same, so you change only the arrangement of the notes while keeping the chord’s role.
Using them in chord progressions
When you write a chord progression, keeping the upper notes as close as possible to where they were makes the movement of the parts smoother. This idea is called voice leading, and inversions are a basic means of achieving it.
How to try it in a DAW
Write a progression such as C to Am to F to G in the piano roll and compare how it sounds as you change the lowest note of each chord. You can try it just by moving a note one octave, without changing the chord names. If you have a separate bass track, check that the low note of the inversion is not fighting with the bass part.
The relationship with slash chords
A slash chord written as C/E means a C chord with E in the bass. It is worth remembering as the standard way of writing inversions in chord symbols.
