John Gill Commentary Nehemiah 12:42

"and Maaseiah, and Shemaiah, and Eleazar, and Uzzi, and Jehohanan, and Malchijah, and Elam, and Ezer. And the singers sang loud, with Jezrahiah their overseer." — Nehemiah 12:42 (ASV)

And Maaseiah, and Shemaiah, and Eleazar, and Uzzi, and
Jehohanan, and Malchijah, and Elam, and Ezer
These seem to be all priests that blew the trumpets:

and the singers sang loud, with Jezrahiah their overseer ;
these were the Levites, that sung the songs of praise vocally, and raised their voices very high, Jezrahiah being precentor, who led the tune, as well as played on instruments.