Well I have written about my L200's before so will skip to the most recent upgrade I have done with these. I added new woofers this summer, the same ones in the JBL 4367 and very close to the M2. Then I bought a Mini DSP 2x4 HD and a little Yamaha A-S 301 to drive the upper end while my 40 year old Kenwood 700M now drives the new (2216Nd1's) LF drivers.
The results have been nothing short of spectacular! Where the old original drivers weren't terrible, they did lack real deep bass and overemphasized that false bass region known as boom. The new 2216Nd1's are nothing at all like that!
I've been working with the DSP PEQ's and have the old L200's digging deep! Here is the frequency response at my listening chair. The lower end is what I have been concentrating on so the upper still needs work. I am now pretty flat down to 30 hz and a 3db dip at 25. Any notion that I needed subs have all but disappeared!
It isn't just that they dig so deep now, but the clarity of the bass, all the way up into the mid range, greatly improved imaging, and for some reason even the HF sounds remarkably better now than before!
These babies were not cheap, $1200 a pair, and I likely would never have done this if it wasn't for my friend and fellow L200 owner,
@nedseg who did his homework on this, and bought one of the drivers just to try it. His reports were so good that I just dived into the deep end of the pool.. The sound I am reproducing now from these was well worth It!
The 2216Nd1:
My L200's as they are now, 44 years since I bought them new at 19 yo.. They have 077 tweeters, rebuilt LE85's and biamped.. They now seriously have the ability to kick ass if I say so myself!