I only know Troels Gravesen based on his L100 century filters which have been very popular here in Denmark.
Having had 4 pairs of L-100 myself, restoring and showcasing them for friends and on forums i have heard more times that i like to, that "If you want them to sound better - make the Troels Gravesen filter".
While i do admire the filter Troels Gravesen makes and his way of working, the sound of the filters aren't for me - it takes away some of what i like about JBL. It might not be a "Theoretically correct" sound in terms of modern loudspeaker designs, and you can throw better crossover charts at me all day, but that doesn't change the fact that, in my mind, it takes away what i like about the sound. which leads me to my critique, because there is something I just simply cannot fathom in the approach:
If you don't like the sound of your speaker - why not buy a different speaker?
I love my JBL's for how they sound - with good and bad. There are a lot of people who love their original JBL's as well, and who has a hard time getting a pair that is still original, and in good condition.
Instead of modding or tricking out your speaker to become something else, why not sell it to someone who wants exactly that, and look for something that kills the itch? (Or buy all the components and build a clone
)
and of course, i know it is fun to tinker, and that you don't necessarily harm any part of the speaker, trying a new crossover (As long as you take care with foilcals taking out the filter screws and keep the L-pads mounted since the new filter doesn't use them) - but still?
I often compare vintage audio with vintage cars - it seems counter-productive to make your old mustang into a vintage jaguar