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sus4, add9 and 7: the colours worship players use

By Adrian · 9 October 2026 · 7 min read

sus4 delays a chord, add9 decorates it, and 7 adds tension. They're colours on top of the chords you already know. Each one has its own job, and once you know the job, you know when to reach for it.

(If the numbers are new to you, start with Nashville numbers explained.)

sus4: the chord arrives a little later

sus4 delays the satisfaction of a clean chord. The 3rd of the chord is replaced by the 4th, and the ear waits for it to come back. I usually choose it when a chord will be held for several beats: it keeps the music from standing still, and it makes the chord's arrival a little later.

If you have a whole bar of G, you can play two beats of Gsus4 and two beats of G. If you have two bars of G, play one bar of Gsus4 and one bar of G.

In a song: Amazing Grace

Here's the first half of the verse of Amazing Grace in G. On "me", the melody holds one long note for two bars, over 5. Switch to sus4 and the first of those bars becomes 5sus4: the line waits a little longer before it lands.

A sus4 can go anywhere it's needed, as long as it resolves correctly when the situation asks for it. It doesn't always have to: you'll see one later that goes straight on to the next chord.

add9: a decoration

add9 is just decorative. It doesn't really have a function, and the chord does the same job with or without it. But it can give you one more note in common with the chord before or after it, so the two sit closer together.

Where to put the 9th: it sounds very nice a 7th above the 3rd. In Gadd9, that's B with the A above it. But it sounds just as good squeezed between 1 and 3: G, A, B.

7: tension that asks to be resolved

A 7 (the minor 7th, as in G7 or D7) creates extra tension. It turns the chord into a dominant. I use it when I want tension, and when I want a chord that isn't the dominant to have the effect of one and ask for a resolution.

How to play it: I usually put the 7th under the right-hand thumb. And keep in mind that the minor 7th really has to resolve downwards: in G7 to C, the F steps down to E.

7 on a minor chord

On a minor chord, like Em7 or Bm7, the 7 doesn't make a dominant. There's no pull to resolve; it's closer to add9, a softer colour on top of the chord.

The mistakes I see

I think students don't give colours enough importance. They don't experiment with them enough, and because they play them rarely, mistakes slip in when they do: they mean to play Gsus4 but play the wrong notes, or they have to play E7 and, from lack of experience, play a major 7th instead (D♯ instead of D).

The cure is simple: play them more often, on purpose, until they feel as natural as the plain chords.

Be Thou My Vision, with colours

You may know this one from What does 5/7 mean: Be Thou My Vision in D. Here's how I play it with colours. Switch to plain chords to hear the same verse without them. The chords in gold are the ones that change.

What to listen for:

• Line 1: D is held for two bars, so Dsus4 keeps it from standing still and resolves back to D on "Lord". Then A7 pulls home, and its G steps down to F♯, the melody note on "heart". Dmaj7 there is the dreamy one.
• Line 2: in Dadd9/F♯, the melody sings the 9th itself: the E on "else". Then the line ends on Asus4 and doesn't resolve. It goes straight on to Gadd9 in line 3. They share A and D, so nothing has to move far.
• Line 3: Gadd9 and Bm7 share the A. In Bm7, the melody itself sings that A.
• Line 4: A7 is the real dominant, and its G steps down to F♯ in the final D. The last chord is a plain D: the melody sits on D, and a major 7th right under it would rub.

Next: colours sit on top of the numbers, so the numbers come first. If you can't hear them yet, start with How to play worship songs by ear.