Written by Gary Ewer, Senior Instructor, Dalhousie University, from “The Essential Secrets of Songwriting” website.
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Substituting one chord for another is a useful way of injecting some life into an otherwise mundane chord progression. But it can’t be done haphazardly. Remember, even though the musician in you likes innovation, the listener strongly values the predictable nature of repetition, particularly when it comes to chord progressions. Chords can, however, be an area of songwriting that benefits from occasional substituting. Here are four things to keep in mind:- Chords usually act as a backdrop for something more interesting. So an unassuming chord progression may be important to maintain. Think of it this way: a wall in a house is usually painted a rather plain colour, and this works well by not drawing attention away from a more vibrant work of art that may be hanging on that wall.
- To substitute one chord for another, it’s best if the substituted chord has at least one of the same notes as the original chord. By keeping the melody notes the same, this is usually assured.
- A chord substitution usually creates a surprise to the listener, so use substitutions sparingly. As mentioned earlier, a listener needs predictability as much or more than innovation.
- Changing the last chord of a verse or chorus creates what is called a “deceptive cadence.” This can work well especially when connecting a chorus to a bridge.
Here are a couple examples of chord progressions, with some standard chord substitutions. (The examples are all given in the key of A major. Keep in mind that the chord substitutions only work if they incorporate your melody note at that moment.):
a) Original:
A D E7 A
With possible substitutions:
i) A D E7 F#m
ii) A Bm E7 F#m
iii) D A/C# Bm A
b) Original:
A F#m D Bm E7 A
With possible substitutions:
i) A F#m Dm Bdim E7 A
ii) A D Dm Bm Bdim A/C#
Some substitutions are very common. For example, in general, you can often replace a I chord (A) with a vi-chord (F#m), a IV-chord (D) with a ii-chord (Bm). Also, using a minor iv-chord (Dm) sometimes works well in place of the normal major IV-chord (D).
As a sort of universal example, try humming the first phrase of “Twinkle Twinkle Little Star” to the following standard chord progression (Remember, the note after the slash is the note that should be the lowest sounding note of the chord):
A A/C# |D A |E7 A | E A (etc…)
Try singing the same melody with these chords:
A A/C# | D A7| D A/E | E F#m (etc…)
My advice, however, is to use chord substitutions sparingly. Remember that most songs need a strong dose of predictability to work well. Substitutions should be used to freshen up a progression, particularly in the latter half of a song.
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HI Gary. I didn’t understand the substitution iii) of the example a).D A/C# Bm A
Is it a kind of displacement? thank you in advance.