Tension and Release is an often used term for analyzing music, to describe how music keeps the interest of a listener. In Western tonal music, ranging from European classical music to modern pop, tension is often thought to derive from the dominant chord. Release is said to occur when the music then reaches the tonic chord or "one chord" based from the first scale degree of the key. In atonal music or improvised music, such as free jazz or jam band music, harmonic progressions are not necessarily recognizable, but audiences still often perceive suspense and resolution, closely related to the concepts of tension and release, respectively.
Seen in terms of its phenomenology for the musician performing an improvisation, this experience can be attributed to different temporal relationships between a musician's cognitive perception of the notes played and the physical sounds from the instrument. If the musician is internally choosing the notes to be played a moment before each note is actually played, this tends to involve an active assertion of the will on the course of musical choices and will often be perceived as a kind of tension. By contrast, if a musician takes a less active role in choosing new notes, but simply repeats the same pattern while effectively only listening to the sounds after they are played, this can create a sensation of release.