Enter Music and Design
MusicAndDesign, a web site created by John Kreskovsky, closed as of 1 Sep 2019. His contributions to the speaker building knowledge of both amateur and professional alike have been significant. His site contained a wealth of technical information with emphasis on dipole physics. I found it invaluable as a learning and reference site. My dipoles were designed using his dipole spreadsheet. I am unaware of any similar software.
Loss of this resource, despite the wayback machine access, for online searches prompted me to request his permission to host his site as an archived copy. He gratiously agreed. It will remain as long as my web site, SpeakerDesign, remains active.