That's a very good question!
Apologies if this isn't the best place for this question, but I just receved a gift last night from family in the form of a pair of vintage "Jim Lansing Signature" speakers. I opened them up, and they contained 'D130s', '075' ring radiators, and '2600' crossovers. (The '030' configuration?)
I've scoured google/audioheritage.org, and--best I can tell--these are likely from the late '50s. The cabinets, as you'll see from the pics--are ginormous! (note the ruler in the pics--approx. 26" "tall" by 36" wide) Some interesting observations: The ports are in different locations in each cabinet. Also, the tweeter is in the upper right corner on each, instead of in a mirrored fashion.
I hooked them up to my vintage Denon PMA-501 last night and they sound--for their age--miraculous! But I'd love to know more about them--does anyone have any direct experience with this family of speakers? Also, I feel like they'd be well-served by bypassing the original crossovers (while preserving them in their original state) and installing an updated crossover network on the back (the bottoms and backs are unfinished, and I'm gathering these may have had feet at one point...). Any drawbacks to this?
Any insight/personal experiences would be appreciated...