1 Chronicles 25:6-8

Amplified Bible

⁶ All these were under the direction of their father to sing in the house of the Lord, with cymbals, harps, and lyres, for the service of the house of God. Asaph, Jeduthun, and Heman were under the order and direction of the king. ⁷ So their number [who led the remainder of the 4,000], with their relatives who were trained in singing to the Lord, all who were skillful, was 288.^(A)

Divisions of Musicians

⁸ The musicians cast lots for their duties, everyone alike, the small (younger) as well as the great (older), the teacher as well as the student.