Basics of Secondary Dominants on the Guitar
Non-tonic-but-still-dominant chords on the guitar are called secondary dominants. The relationship between the tonic and dominant chords is so strong that composers sometimes use a dominant function on chords other than the tonic, like on the ii chord or perhaps even the V chord itself. You recognize them in chord progressions as major chords where you’re expecting minor ones and especially as dominant 7th chords where you’re expecting simple triads.
For an example, look at the C major progression: C-Am-Dm-G7. A common variation on this progression is C-Am-D7-G7, as shown here. You would normally expect a D minor chord rather than a D7 chord in C major, but if you think about this progression, you can see that the D7 chord is the dominant 7th of G.
Common secondary dominants on the guitar
Musicians use secondary dominants on almost any chord in a key to provide some variety to a progression and to give some temporary focus to another chord. For example, the D7 chord shown has a different sound quality than a simple D minor chord, which is what you normally find in the key of C.
Because the chord has a dominant function, it draws attention to the following G7 chord. It’s as if the chord progression temporarily changes keys to G.
You can lead to almost any chord with its own dominant. A chord’s dominant is a major chord or dominant 7th chord that’s a 5th away from the chord itself. Building on the previous example, you could lead to D with A7, which is five steps away from D, the interval of a 5th, as shown here.
You can see how to play the secondary dominant in Secondary Dominants.
Keep going! The 5th of A is E, and an E7 chord can lead to any type of A chord. Here is an example of E7 leading to A7 in a series of dominant 7th chords that begins on E7 and moves to C.
Another common secondary dominant progression is I7-IV. In C major, this progression is C7 moving to F. An example of this secondary dominant’s use is in the larger progression F-G-C-C7-F-G-C that you see in here. The progression is in C major, but the C7 chord is functioning as a dominant 7th of the F chord.
The most common secondary dominants are the ones you see here — those that lead to I, ii, IV, V, and vi. Musicians generally don’t use secondary dominants that lead to viif5, and although V7 of iii is possible, it isn’t very common.
Songs on the guitar that use secondary dominants
The following songs all feature chord progressions that make use of a secondary dominant either as a dominant 7th chord or, in some cases, a major chord on a minor scale degree. Secondary dominants are in parentheses.
Every Breath You Take by The Police (Chorus: II chord leads to V)
Faith by George Michael (Chorus: II chord leads to V)
Heart of Glass by Blondie (Chorus: II chord leads to V)
Hello Mary Lou by Ricky Nelson (Chorus: III chord leads to vi and II chord leads to V)
Hey Good Lookin’ by Hank Williams (Verse: II chord leads to V)
Hey Jude by The Beatles (Verse: I7 chord leads to IV)
Honky Tonk Women by The Rolling Stones (Verse: II chord leads to V)
Margaritaville by Jimmy Buffett (Verse: I7 chord leads to IV)
Patience by Guns N’ Roses (Verse: II chord leads to V)
Running on Faith by Eric Clapton (Verse: I7 chord leads to IV)
The Star-Spangled Banner (U.S. national anthem) (Verse: II chord leads to V)
That’ll Be the Day by Buddy Holly (Verse: II chord leads to V)