Dhrupad is the oldest continuously performed genre of North Indian classical vocal music, distinguished by its unhurried, deeply meditative approach to melodic development and by a vocal style considered austere and weighty compared to the more ornamented styles that developed later from it. A dhrupad performance opens with an extended alap, an unmetered, slowly unfolding exploration of the raga's notes and characteristic phrases sung without percussion or fixed rhythm, sometimes continuing for a considerable length of time before the composition proper, set to a fixed rhythmic cycle called a tala and typically accompanied by the pakhawaj, a two-headed barrel drum, begins.
The genre traditionally sets devotional and philosophical texts, frequently addressed to a deity, and its performance style favors resonant, sustained tones and a deliberately restrained approach to ornamentation, in deliberate contrast to the more rapid, virtuosic melodic elaboration associated with khayal, the classical vocal style that later grew out of and largely supplanted dhrupad in mainstream North Indian concert practice. Dhrupad is traditionally performed by a soloist or, distinctively among Indian classical vocal genres, by pairs or small groups of singers performing the same melodic line together in unison, a texture rarely found in other North Indian vocal forms.