Inversion seems like a strange word to use for music, doesn’t it? Actually it’s a very common term and is related to how chords are written. Composers use inversion in a variety of ways but primarily to make music sound smooth and subtle. Without inversion, chord changes would often sound jolting to the listener. Let’s look at how inversion works.

It’s important to understand that inversion deals with the lowest sounding pitch in a chord. Although we can invert a chord in a variety of ways, while we’re talking about inversion it’s only the bottom note that we’re moving. When we move other notes in a chord, we’re talking about voicing changes. Music theorists don’t have as many hard and fast rules for voice as they do for inversion.

If we look at a basic triad (remember the triad? C-E-G) When the first scale degree, also called the root, is the lowest sounding note, there is an absence of inversion. This is called root position. Root position is the most commonly used inversion (or lack of inversion) in popular music and used in traditional or classical music to end a phrase, movement, or entire piece of music. When you play a chord in root position, you are telling your listener that the piece is done. Other times, composers use it throughout a piece of music because it is a very pure an open sounding chord.

Next, if we take the “C” and put it at the top of the chord, we now have a chord that is spelled E-G-C. When the third of the chord (third scale degree) is the lowest sounding note, we have a first inversion chord. The most common use for this inversion is to make a chord a “passing” chord or bridge between two chords. It gives the bass voice a smooth walk up a scale as chords change.

While you may not notice first inversion chords as easily as you notice a root position chord, rest assured that they reside in your music quite frequently.

Now, let’s take our first inversion chord and flip it again. That “E” which is currently residing in the lowest spot will now be at the top. We’ve now inverted our chord again and we have a G-C-E chord. This second inversion chord is most commonly used in a “cadential” way. This is a big music theory term that means that this chord sets up a cadence.

For example, a I-V-I should look familiar to you if you read our article about cadences. The “V-I” is an authentic cadence. If the “I” chord before it is written in second inversion, it makes the “V” of the cadence even more of a cliff hanger than the “V” chord could do all by itself.

These are the three ways to write or invert a triad. As we get in to larger, more extended chords, they are even more inversions that serve specific purposes as well but for now, practice these inversions just with the basic triads. There’s plenty of time to learn the other types of inversions available to the composer.