27: Voice Exchanges

Voice exchange is often done in the name of variety. If the same chord were voiced the same way many times in a row, the music would quickly become uninteresting. However, since we have the benefit of this tool, we can swap chord tones between voices, often changing the inversion of a chord in the process, but, in any case, making the texture of the music more interesting by the addition of movement.


Consider this sequence of chords:

A close-up of a music note AI-generated content may be incorrect.

We have two D chords in a row, but this doesn’t sound like the same chord twice. Sure, they’re both fundamentally D chords, but there is something essentially different about how a root-position chord and a first-inversion chord feel. The tenor and soprano voices don’t move at all, but the bass does (and hence we have the inversion change. It would be total legal for the alto not to move at all either, but since we’ve chosen to make the exchange, the alto does move.

Before the exchange, we had D in the bass and F# in the alto, and after the exchange, we have F# in the bass (so we’re now in first inversion) and D in the alto.

Voice exchanges are great ways to add variety and texture to otherwise repetitive parts. Just be careful, if you choose to make an exchange, that such an exchange does not result in a crossing error.

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