Charles Ellicott Commentary 1 Chronicles 9:34

"These were heads of fathers` [houses] of the Levites, throughout their generations, chief men: these dwelt at Jerusalem." — 1 Chronicles 9:34 (ASV)

These chief ... generations. —Literally, These are the heads of the Levitical houses, according to their genealogies, heads. (Compare to 1 Chronicles 8:28 for the meaning.)

These dwelt in Jerusalem. —A final remark concerning all the Levites of 1 Chronicles 9:14–32. The proper names are regarded as chiefs, under whom their numerous clansmen are subsumed.