Parallel
1 Chronicles 9:33
Jewish Publication Society 1917 · Berean Standard Bible
And these are the singers, heads of fathers’houses of the Levites, who dwelt in the chambers and were free from other service; for they were employed in their work day and night.
Those who were musicians, the heads of Levite families, stayed in the temple chambers and were exempt from other duties because they were on duty day and night.