Got it. My JBL 4435 and 4430 studio monitors use a JBL 2344 Bi-Radial horn design, specifically for those two monitors. See below:
https://www.lansingheritage.org/html/jbl/specs/pro-comp/2344.htm]\
Also see: Sound Producers vs. Sound Reproducers. See article below page five:
Mike
https://www.lansingheritage.org/html/jbl/reference/notes/tech1-3a.htm