Harmony Harmony is the simultaneous combination of tones, or musical notes, blended together into formations known as chords. One way to think about harmony is that it represents the vertical aspect of notes piled up on top of each other and sounding at the same time, while melody is the horizontal aspect, with the individual noted following one another in a line. If the chord results in a pleasing sound, it is called consonant. If not, it is called dissonant. Another aspect of chords is that some sound as though they want to resolve or keep moving to another chord, while others have a feeling of finality about them. The interplay between these chords creates something akin to a musical conversation, and the increase and decrease in the tension between them is what makes music compelling and interesting to listen to.