Webster(i)
6 All these were under the hands of their father for song in the house of the LORD, with cymbals, psalteries, and harps, for the service of the house of God, according to the king's order to Asaph, Jeduthun, and Heman.
7 So the number of them, with their brethren that were instructed in the songs of the LORD, even all that were skillful, was two hundred and eighty eight.