2 Chronicles 5:11-12

11And it came to pass when the priests came out of the Most Holy Place (for all the priests who were present had sanctified themselves, without keeping to their divisions),

12and the Levites who were the singers, all those of Asaph and Heman and Jeduthun, with their sons and their brethren, stood at the east end of the altar, clothed in white linen, having cymbals, stringed instruments and harps, and with them one hundred and twenty priests sounding with trumpets—