While I was working on the Mozart C major Sonata, two bars caught my attention. In my experience, often, a bar on it’s own does not generate a meaningful feeling. However, two bars, when placed next to each other, can have a profound aesthetic that the chords alone did not achieve.
You can hear the moment I’m talking about at 1:54. These chords are based off the same root, but have different modes. The first harmony is a G major chord, and the second harmony is a G minor chord. The first harmony is the end of a cadence, signalling an end of a section. The second harmony begins the next section, forging forward with a different mood.
Parallel Key Modulations
The G major section ends on a cheery note, flaunting it’s scale in flying runs. The G minor section retains this acrobatic attack, making me wonder more about how a change of mode can be used. After doing some research online, I found that music theorists call this parallel key modulations. The following video gives instructions on the variety of ways you can modulate using parallel key modulations.
I love the effect that the parallel key modulation has! I am looking forward to exploring it further the next session I play and incorporating it into my own tunes.