How Song Tempo Affects Chord Choice

Back in the early days of the existence of chord progressions, composers discovered (or at least instinctively knew) that the tempo of a piece of music greatly affected how listeners perceived and reacted to chord progressions. It should be no surprise to us that all the various elements of a song are closely tied together. We know, for example, that melody and lyric are strong partners: placing strongly emotional words in at high points in a melody will enhance the impact of those words.

And here’s what they discovered about song tempo and chord progressions:

The faster the music, the less frequently chords should change.The slower the music, the more adventurous and complex the chords can be.

These two points address an aspect of chord progressions called harmonic rhythm. When we talk about harmonic rhythm, we’re talking about how frequently the chords change. Another way of phrasing the first point is to say: The quicker you change chords (i.e., the faster the harmonic rhythm), the more frantic the music tends to sound.

The harmonic rhythm of any given song tends to be relatively stable for the entirety of the song. For example, Kelly Clarkson’s “Stronger” has a harmonic rhythm of 4 beats: essentially every chord lasts for 4 beats. Adele’s “Set Fire to the Rain” has a harmonic rhythm of 4 beats, which then switches to 8 beats for the chorus. Both songs have a similar tempo (approx. 112 b.p.m).

What you’ll notice (and what composers from centuries ago noticed) is that there is a momentary spike in musical energy every time a chord changes. Fast tempos already have a high energy level. So quick chord changes in fast tempo songs tends to make a song sound frantic and panicky.

Which brings us to the second point. Slower tempo songs are great songs for exploring more complex chord progressions, ones that feature lots of non-chord-tones, mini modulations, and harmonic twists and turns.

An example of this sort of thing from the Classical music world might be to compare Bach’s Concerto for Two Harpsichords (played here by two pianos), which wanders quite a bit harmonically, aided by the slower tempo. The slower tempo gives the listener time to “process” and understand what’s going on. If this piece were played quickly, it would sound unpleasantly worked-up and agitated.

Now listen to the 3rd movement of Bach’s Brandenburg Concerto #3, which is usually played at a very fast tempo. That fast tempo means that the chords should change in a very regular way, and should be far less complex. In this example, they rarely stray beyond simple circle-of-fifths type progressions, which are very strong and predictable.

As a writer of songs in the pop genre, you simply need to remember that the more frequently you change chords, the more energy is generated. You can purposely create that “frantic” feeling by doing just that. To see how that works, try this little experiment:

Play the following progression at a fast tempo of 136 b.p.m.: A  D  Bm  E  C#m  F#m  B7  E7. Strum each chord for 8 beats before moving on to the next one. Next, strum each chord for 4 beats, and notice the slight intensifying of energy. Next, strum each chord twice before moving on. As you keep shortening the duration of each chord, the music becomes more and more energetic. There comes a point when the intensity crosses over into the realm of “panicky”, and then you simply have to decide if that’s an effect that you want.

Of course, playing style, instrumental range, and basic rhythm also work to create energy as well, and so all aspects need to be considered together. But if your latest song is giving you that unpleasant frantic feel, try either slowing the tempo down, or simplifying the chord progression.

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