Star Wars theory;
"Jizz" obviously has Big Band influences but we've only seen small live ensembles - Max Rebo Band, Figrin D'An and the Modal Nodes and two vocalists in Solo.
Based on how big bands gave way to smaller groups in the late 40s, and how the SWverse is less obviously prosperous after the Clone Wars, I'm assuming that before jizz popular music of the Old Republic drew on 30+ musicians.