“And the Priests waited on their offices: the Leuites also with instruments of musicke of the Lord, which Dauid the King had made to praise the Lord, because his mercy endureth for euer, when Dauid praised by their ministerie: and the Priests sounded trumpets before them, and all Israel stood.”
1611 King James Version (KJV)
7:6 David praised - For David composed the psalms or hymns, and appointed them to be sung by the Levites, and instrumental music to be joined to their voices.