Very interesting discussion here. I thought I would pipe up with a comment on the old tweeters/ferrofluid issue. I’ve had Richard So rebuild multiple pairs, and the improvement is palpable. I’m a firm believer in home audio that if it sounds good it is good. In my case I was trying to bring my Dads old L1290 back to life, and I was hearing them as sharper, almost brittle, spitty tweeters than I remembered them from 35 years ago. I have 4 pairs of ADS speakers, and so far all of the tweeters were problematic. They weren’t quieter, but instead had a “spikier” sound with certain frequencies distorting. It’s not like they were unlistenable, but on modern production with a lot of high frequencies they just weren’t right.
Right now I have two head scratchers: the 1290s sound pretty good, but the bass seems untight, sort of underfined, not punchy I actually have two pair of 1290s and they both sound like this. But it just doesn’t seem right. I’m experimenting with some high quality parametric EQs and also some bi-amping to see if I can tighten this up. I’m also pull out some slight edge in the high mids . Just by ear, I sweep the frequencies until I hear a some ringing then notch it out. This is a new approach but I think it has huge potential to dramatically improve some of these older speakers, which are already quite excellent
