Alap

The Alap (; ) is the opening section of a typical North Indian classical performance. It is a form of melodic improvisation that introduces and develops a raga. In dhrupad singing the alap is unmetered, improvised (within the raga) and unaccompanied (except for the tanpura drone), and started at a slow tempo. For people unfamiliar with the raga form, it introduces the thaat to the listener. It defines the raga, its mood, and the emphasized notes and notes with a secondary role.

Instead of wholly free improvisation, many musicians perform alap schematically, for example by way of ''vistar'', where the notes of the raga are introduced one at a time, so that phrases never travel further than one note above or below what has been covered before. In such cases, the first reach into a new octave can be a powerful event.

In instrumental music, when a steady pulse is introduced into the alap, it is called jor; when the tempo has been greatly increased, or when the rhythmic element overtakes the melodic, it is called jhala (dhrupad: ''nomtom''). The jor and jhala can be seen as separate sections of the performance, or as parts of the alap; in the same way, jhala can be seen as a part of jor. Provided by Wikipedia