1 Chronicles 25:5-7 New American Standard Bible (NASB)

5. All these were the sons of Heman the king's seer to exalt him according to the words of God, for God gave fourteen sons and three daughters to Heman.

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 direction of the king.

7. Their number who were trained in singing to the Lord, with their relatives, all who were skillful, was 288.

1 Chronicles 25