Every year before the Christmas season I use some favorite seasonal songs to teach the concept of the secondary dominant chord and do ear training. Christmas songs are perfect because everyone knows the melodies and melodies indicate harmony.
Many of you will already be familiar with I IV V chord progressions as the go to chords for every singalong type situation but they don’t always work as you may have already discovered. There is a secondary group of chords that is almost as necessary as the ubiquitous I IV V and these are what we are going to look at today in the hope that you may just grab your guitar and try them out around the Christmas tree.
I want to keep this as simple and clear as possible so here we go. Let’s use C major as our example key.
The Primary Dominant
The V chord in every major key is called the dominant and is very often played as a 7th chord, or 4 note chord. Ex: C – F – G7. For today’s lesson we will play all V chords as 7ths. In terms of harmonic behavior the V7 chord wants to return to the tonic or resolve to the I. Let’s use Rudolph and Jingle Bells as examples. Sing the words in your head.
Jingle Bells (Verse)
So the G7 always returns to the I, never goes to the IV. Let’s make a rule, V7 resolves to I. This V7 is called the primary dominant chord because all of its notes are derived from the tonic scale of C.
The Secondary Dominants
What if we gave the F chord and the G7 chord their own dominants as if we were in those keys. A dominant is a fifth away from the tonic. So count 5 starting on tonic I up from F to C7 for its dominant, then count up a fifth from G7 for its dominant of D7. Now we have two new dominants that are secondary to the key because they were not derived from the scale of C. These dominants of C7 and D7 are called Secondary dominants in the key of C and they will want to return to their tonal centres.
Example I: C – C7 – F, C7 borrowed from key of F and leads to F, note the Bb note in the C7 chord borrowed from key of F.
Example II: C – D7 – G7 – C, note that D7 moves to G7 and G7 returns to C as in our rule. Also note the F# note in the D7 chord that comes from G.
So now we are still in the key of C but we have added two new chords from the closely related keys of F and G.
C – C7 – F – D7 – G7 – C. Watch the direction of the chords, the new secondary dominants will always return to their tonal centres and G7 will return to C.
Silent Night (3/4 Time)
Notice how G7 returns to the tonic and how the secondary dominant C7 sets up the F or the IV.
Frosty the Snowman (Verse and Chorus)
Again, notice how C7 resolves to F, how G7 resolves to C and how D7 resolves to G7.
This is all about being able to “hear” these progressions and this is no different than hearing and anticipating any other chord progression in any other style. Christmas tunes are a fun way to sharpen those hearing chops and with the introduction of the secondary dominant you should be able to play a number of seasonal tunes by ear.
Try: Frosty the Snowman, Jingle Bells, Rudolph, Santa Claus is Coming to Town, Silent Night, We Wish You a Merry Christmas, Go Tell it on the Mountain, Blue Christmas, Jingle Bell Rock and many others.
This is obviously not meant to be an exhaustive approach to secondary dominants and harmonization but it might provide some Christmas fun and teach you the function and concept of the secondary dominant chord at the same time. Also please note that harmonizing a melody can be a simple or complex affair, these harmonizations are simple and provide some basic examples to get you off to a start with understanding an important harmonic concept.