They actually get a fair bit of love in the pro audio world as they are a very acoustically efficient cabinet design. However they are are more complex to design and much harder to fine tune than ported, Im can’t be much help in the design process of one at this time unfortunately.
I can reach out some of my contacts in the pro audio speaker manufacturer world and see if anyone is willing to share some secrets on the magic of band pass cabinet design, no promises but I’ll see what I can dig up
Josh Evans, Professional Live Sound Engineer, High End Commercial AV Install Technician
