Accelerando

In music, a marking (usually abbreviated as Accel.) that indicates an acceleration in the speed of performance, and consequently an increase in the tempo of the piece. One task of a conductor is to determine the precise tempo of a work that she or he conducts. The conductor indicates the movements of acceleration and deceleration of the musical stream based on this chosen tempo. Musical accompaniments for cartoons frequently use the accelerando effect – for instance in establishing chase scenes where image and sound follow the same progression. Apart from the musical domain, we can observe this effect in many animal cries and salvos.