Attack

The initial part of a sound, from its onset to the point where its amplitude reaches a maximum.

See: Click, Pulse, Transient, diagrams under Envelope, Fourier Analysis. Compare: Decay, Rise Time, Stationary State.

The attack characteristics of many sounds in the contemporary environment have changed significantly from their older counterparts, often as a result of their electroacoustic production. For example, the electronic triggering of emergency warning signals results in a very fast attack time, whereas earlier devices were constrained by mechanical inertia. See also: Impact Sound.