1 Chronicles 16:42

Of Jeduthun, the sons of Jeduthun: Gedaliah, Zeri, Jeshaiah, Shimei, Hashabiah, and Mattithiah, six, under the direction of their father Jeduthun with the harp, who prophesied in giving thanks and praising Yahweh.

in unison when the trumpeters and the singers were to make themselves heard with one voice to praise and to give thanks to Yahweh, and when they lifted up their voice accompanied by trumpets and cymbals and instruments of music, and when they praised Yahweh saying, “He indeed is good for His lovingkindness endures forever,” then the house, the house of Yahweh, was filled with a cloud,

From the outside to the inner gate were chambers for the singers in the inner court, one of which was at the side of the north gate, with its front toward the south, and one at the side of the south gate facing toward the north.