What on Earth are Sus Chords?

So you already know what major and minor triads are. And you know augmented and diminished triads as well. We’ve even talked about the power of dyads. But what on earth are Suspended chords (aka sus chords)?

In case you forgot, a triad is basically a chord that is a set of 3 notes that can be stacked in thirds. 

In other words, the first note to the second note is a 3rd and the second note to the third note is another third. 

Or, put another way, a triad is a 1st, 3rd, and 5th. 

Any time you see something like “C major”, “F# minor”, or “B diminished”, those are forms of triads. 

But sometimes you’ll see something like “Dsus”, “Gsus2”, “C#sus4” or “Bb minor sus”. These are suspended chords. 

Sus chords allow us to color our chords a bit more, making our music more interesting. 

What Are They?

Sus chords, like major, minor, augmented, and diminished triads, have 3 notes. 

So what are suspended chords?

Basically, they are chords were we “suspend” (or leave out) the 3rd of the chord and replace it with a 2nd or 4th. 

Let’s take a look at what a Csus4 chord would look like. 

First, we need to get our C triad. A C triad will have a C, E, and G. Because we’re going to replace the 3rd, we don’t actually care if it’s a C major or C minor triad. 

Now, we have a Csus4, so we remove the 3rd and replace it with a 4th.

The 3rd of our C chord is E, so we remove that and replace it with the 4th. The 4th in a C chord would be F, so a Csus4 chord would be a C, F, and G. (C, D, E, F, G)

So what would a Csus2 be? It would be a C, D, and G. (C, D, E, F, G)

Sus4 chords are so much more common than sus2 chords so, when you see a “sus” label without the number specified, always assume it to be a sus4.

So a “Csus” is implied to be a Csus4, not a Csus2. 

What Makes Them Interesting?

Let’s take a look at part of why these chords are so interesting. 

Our Csus4 (or just Csus) chord has a C, F, and G. So it still has the 1st and 5th from the C triad. It’s only missing the 3rd. 

But the F makes this chord very interesting, because we have both an F and a C, which make up the 1st and 5th of an F chord. 

So, in a sense, our Csus chord is a hybrid between a C chord and an F chord. 

In the key of C, this would result in a chord that shares a lot in common with both the I and the IV chord – 2 strong and important chords in any key. 

But what about our Csus2 chord? It has a C, D, and G, so it also has the 1st and 5th from the C triad. 

But this chord has a D. But the chord also has a G, and a G and D are the 1st and 5th of a G triad. 

In the key of C, this results in a chord that shares a lot with both the I and the V chord.

So, in a sense, sus4 chords are hybrids of the named chord and the chord a 4th higher, and sus2 chords are hybrids of the named chord and the chord a 5th higher. 

This gives a ton of options melodically, as well as options for interesting chord changes. 

Think about it. If you have a normal triad, your strongest melodic notes you have to work with are limited to the 3 within the triad.

But if you have 2 out of 3 notes for 2 different triads? All of a sudden you have 6 pretty strong melodic notes you can play with. 

As far as sound goes, a Sus4 chord is going to have a massive pull to resolve. So a Csus4 (or Csus) chord greatly desires to resolve to a C triad. In the key of C, playing a Csus will have an almost physical pull to resolve to a C major triad. 

So Sus4 chords are most often used to create some interest before resolving to the normal triad. 

Sus2 chords have much less of a pull to resolve than their sus4 counterparts. So much so, that I actually built an entire song off of a Csus2 chord in the right hand piano part.