and all the Levitical singers--Asaph, Heman, Jeduthun, their sons, their brothers, dressed [in] fine linen, with cymbals, harps, and stringed instruments--[they] were standing to the east of the altar. And with them outside [were] one hundred and twenty priests [who were] trumpet blowers.

and from the descendants of Heman: Jeiel and Shimei; and from the descendants of Jeduthun: Shemaiah and Uzziel--

And the singers, the descendants of Asaph, [were] at their stations according to the decree of David and Asaph and Heman and Jeduthun, the seer of the king. And the gatekeepers [were] at {each gate}. They did not need to depart from their service, for their brothers the Levites had made preparations for them.