1 Chronicles 25:7-9

Amplified Bible

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.

⁹ The first lot for Asaph fell to Joseph; the second to Gedaliah, to him, his relatives and his sons, twelve;