Harmony Discussion #1: Dominant Chords - How do they work??


Music takes its listener on a journey with every note, changing a listener’s response at every junction, through the highs and then to the lows. Ever wondered how composers and arrangers achieve this? And how music endings let you feel at peace after a joy ride through the past few minutes? One of the tools composers commonly employ is the use of dominant chords. Dominant chords are used in every piece of music, as it is an effective way to signal a cadence or a change in mood. To understand this, we must first discuss the conception of tertian harmony in the common practice period.


In the Western tradition after the 17th century, harmony is generally defined through the use of chords. The tertian harmony, formed by stacking intervals of thirds on top of one another gained popularity due to the blend of consonance and dissonance it brought. The dominant chord is an important member of this family of chords, achieved by starting the sequence mentioned from the fifth scale degree of any key. Take C Major as an example. By counting till the fifth degree, we would get G, which is dominant of C Major. A common way of voicing the dominant chord would be to use triads, stacking 2 other notes on top of G. in our case, we would be able to form G, B and D or simply, G Major Triad. We could also stack more thirds to our triad, up to four more to form more complex sounding chords. However, for now, let’e just stick with our G Major triad first.

Moving on to the common practice period, though there are no exact dates for this phenomenon, musicians generally agree that this period started from the mid-Baroque period lasting until the Impressionist period, widely considered as the decline of tonal harmony. However, during the common practice period, tonal harmony or conventional harmony dictates that a piece of music should have a blend of consonance and dissonance, or in common terms tension and release. Frank Zappa once said that “The creation and destruction of harmonic and 'statistical' tensions is essential to the maintenance of compositional drama. Any composition (or improvisation) which remains consistent and 'regular' throughout is, for me, equivalent to watching a movie with only 'good guys' in it, or eating cottage cheese”.

Dominant chords contribute to this standard by providing all the tension that composers need in their composition. Dominant chords by themselves sound volatile and has a need to be resolved to a more grounded or consonant chord, for example, the tonic. This particular relationship is what composers refer to as a perfect cadence. Listeners are terribly familiar with this cadence, as this is normally what we hear on the endings in commercial recordings.

Dominant chords also act as the pivot chord, or in simple terms the bridge in between 2 keys. This arrangement happens very often in music that has a modulation, a change of key. The common practice period embraced the modulation to provide interest and drama to musical pieces. Usually, the dominant chord of the new key is used in order to prepare the listeners for the change of key.


As music evolved through time, so did harmony. Still based on tertian harmony, dominant chords began to embrace the additional ‘tension’ notes as discussed earlier. By including these notes into the dominant chord, what they produced was a new sound palette ready to spark the composers’ creativity. This new sound palette would lead to more harmony-enriched works which began to show prominence starting from the Romantic era.

If you are interested to learn more about music theory and harmony, consult your music teacher!

Play on and Tinkle Away!!