The singers, the sons of Asaph, were also at their stations according to the command of David, Asaph, Heman, and Jeduthun the king’s seer; and the gatekeepers at each gate did not have to depart from their service, because the Levites their brethren prepared for them.

and all the Levitical singers, Asaph, Heman, Jeduthun, and their sons and kinsmen, clothed in fine linen, with cymbals, harps and lyres, standing east of the altar, and with them one hundred and twenty priests blowing trumpets

and from the sons of Heman, Jehiel and Shimei; and from the sons of Jeduthun, Shemaiah and Uzziel.