The origins of the Tabla, the twin vertical drum set, are a subject of conjecture. The Tabla surfaced around the 15th century in response to the need for a softer and more agile rhythmic accompaniment than the Pakhawaj. This need arose from the ascendancy of Khayal vocalism and, later, the arrival of modern instruments such as the Sitar. Tabla is the primary accompaniment for Hindustani music and has also gained prominence as a solo percussion instrument. It is also used in devotional music genres.