Tension

Musical instability created by a chord that calls for resolution.

Tension is the musical sensation of instability created by certain chords or notes that 'call for' resolution. Dominant chords (V) create strong tension that resolves on the tonic (I). Extended chords (9, 11, 13) add colourful tensions without always demanding resolution. Understanding tension is essential to composing or improvising intentionally, by playing on the alternation between tension and release.