A suspension is one of the most important and expressive devices of classical harmony. Its essence is that one of the notes of the previous chord is “held over” and sounds together with the new chord, to which it does not belong, creating a sharp dissonance, and then resolves smoothly — most often descending by a step.
A classic suspension consists of three phases: the preparation (the note sounds as a consonance), the suspension proper (the same note becomes a dissonance on a strong beat), and the resolution (the move to a stable note). This device creates a sense of “sighing,” tension, and sweet pain, so composers from the Baroque to the Romantic era used it widely to heighten emotional expressiveness. The suspension is the soul of expressive voice leading.
