@michaelgreenaudio I too am curious about this tuning method that you reference. I am always open minded to any possibilities, and look forward to reading your posts, once posted. As a guitarist, I disagree somewhat on your comment on tuning being accurate in one room, and moving to another room makes the instrument sound out of tune (if I am understanding you correctly) I agree that an acoustic guitar will "sound" different, room to room, but not out of tune. I'm also curious about your drivers being tuned to the cabinet, AND the room. So, if a potential customer were to purchase your speakers, how do you determine the correct tuning methodology for that individuals room?
As for the original question from the OP, I have a little story about my vintage/modern comparison. Back in the mid seventies, as a budding young (but poor) audio enthusiast my first "decent" pair of speakers where the Altec Lansing Model 3's (don't laugh, I was just a kid). Now at that point in time the shop I was dealing with also had a pair of the Model 15's. For me at the time, they were my unattainable Holy Grail. Time marches on, and now decades later, and many different speakers, I am running a pair of Wilson Maxx 2's, and also have a set of Wilson Watt Puppies in reserve.. Recently I had an opportunity to purchase a pair of decent Altec Model 3's. I did so purely out of a sense of nostalgia. The same weekend I also found a pristine set of the Altec Model 15's. I just HAD to have them. Brought them home and built a pair of custom "pig-tails" for spade connecting, so as not to modify the stock binding posts on the 15's. Well, after listening for a while, my thoughts were; WOW !! These really sound awful !! LOL
Sorry for being so long winded. My Bad!!