Hi, I've been lurking this forum and site, for years now. So...
I am building speakers since probably fourteen years old. Projects were always cheap or even no budget builds, with a lot of recycling. A log time ago, when I was starting building speakers friend borrowed me one old speaker which looked a lot like D 130 but i am not certain if it was JBL or RCF copy of JBL, it was in pretty rough shape, and I have build several enclosures for it, and then had to give it back to owner. There was something special in that driver, that i never forgot.
Six or seven years ago in one trade I have acquired two JBL K 130 driver, they were in very rough shape, so I reconed them with D 130 recone kits. Aftermarket ones. Blasphemy I know, but originals are so expensive.
On this site I have found and build few bass reflex enclosures, but that wasn't it, so at the end I have built 4530 horns. Now, that was good. Well, almost good. Those horns goes down to about 60 Hz. So I have recalculated Jensen Imperial built in horn for D 130 and that should go quite flat to 45 Hz (according to Horn response) But, those are big and WAF is near the red areaso I am thinking to build Hartsfield top loader instead. And that is where I stuck. Because it looks that plans for those speaker are drown on invisible paper.