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View Full Version : L200 21st century mods??



nedseg
04-19-2017, 10:09 AM
Hello!
First new thread here, but long time 'listener/learner' from all the great conversations here.
Sorry it's so long winded, but I've been thimpking about this for months and months, and finally decided to post here in the spirit of "Don't know? Don't Guess. Ask!"

Introductions wise:
I recently retired from technical/project management, and finally have time to look into maintenance/upgrades for my 1974 L200s, which had the LX16/077s added to them by my JBL dealer shortly after purchasing new. Haven't been opened since, the cabinets are pristine, and they have new foam grills on them, so they still 'look' new.
I've read all I can find on upgrades for these, and am working towards cracking them open for inspection/repair and upgrades.
(And many thanks to Heather, Toddalin, et al, for sharing their experiences!)

I'm currently working my way up the REW learning curve so as to have good 'before' and 'after' data.

But, my question is not about 'standard' upgrades, but the feasability of major mods.

Basically, from discovering that the LE15Bs were consumer versions of the 2216 (and searching on that), and following so many of the DIY M2/4365 threads, I began to wonder if it would be worth the effort to simply upgrade these cab's to the M2 drivers! Would that be cool, or what?

They are 5 cu ft cabs, after all, and the 2216ND(-1s..whats the difference?) and 2430K(?) drivers seem to be available new....which I like a lot (after 40+ years on the 'old 'uns, maybe time to change centuries and get another 20 years - all I care about - out of them?).
Plus, I'm soooo impressed with the waveguides on the LSR305s, I can't help but wonder.....

I'm experienced with cabinet/woodworking and electronics, and could even see modifying/replacing the baffles and opening up/raising the bases as per Toddalin, if necessary.

Couple of add'l factoids:
- No, I'm not interested in building new cabs; I love the way these things look, afterall have been hauling them (very carefully) from house to house for decades...and I have too many other woodworking projects cued up already. (And have a room full of walnut Eames furniture which matches nicely!)
If I'd started into this earlier in life, I would have loved to do that tho!
- Whether I make major cab/driver mods or not, I'm considering going active DSP (Venu360?) and biamping them, anyway.
- (I've researched the NelsonPass xover mods, and could do that, might even try for the sake of it anyway...but even those might require mods for the LE15Bs? If I kept them.)

- The cost of new 2216NDs seems to be about the same as properly restored 2235Hs, which, as I've stated in earlier replies, I'm just not all that sold on them since A/B'ing these modified ones against new L300s back in '75/76.
The LE15s just sounded 'richer' to me on acoustic bass (but the L300s did do 'Rock 'n Pop' a bit better).
Stubborn? Yes!

- I almost hate to admit it, but I do like the way these sound (albeit with a bit of EQ via UMC-200 currently) as is, but am tempted by all the comments I've read about the 'tightness' of the 2216NDs/M2 bass. Present amp is a Bryston 3BNRB.
- I have a 4645C/Crown 1502 subwoofer, so not too concerned about extended (say, < 80hz) LF response, and not really looking for DC to Light anyway (but these are part of a 7.1 HT system...but don't watch that many movies.)
- I listen to mostly acoustic music (but have recently discovered some interesting electronic stuff I like -esp synthetic bass), and can still hear the 077s difference (one of them is not working - it quit sometime after one of the last house moves, and is the main reason for wanting to crack them open)...my hearing is still pretty good out to 13-14khz.
The sound of 'rosin' on bowed instruments from these things still sends a chill up my spine!

- If I proceeded with this (whatever "this" ends up being), I'd do one first so as to be able to directly compare 'before & after' and measure (REW) the differences.
- Pending more REW work, the original LE15Bs still seem to work fine, tho I'm not sure how anyone could tell for sure.
I bought a spare set, thinking to have the 'best old pair' reconed, but then the 'idea light' went on, darn it.

So, my questions for the experts here are:
1. Is this just a silly notion? ("BAD IDEA" is a fair response...but would like to know 'why' just the same.)
2. Would the 2216NDs work at all well in that cabinet?
(I'm thinking in terms of 'buying and trying' that first, as it would appear to be a fairly straightforward swap), or would they require cab volume mods?
I expect lots of fussy detail on these two points...speaker modeling software is a bit beyond my current interests...again, too many other projects in flight.
3. Same question about the M2 HF drivers..though I'd expect that would require major baffle mods (or replacement).
4. The avialability of the waveguides for the HF would seem to be a problem - If answers to #2 and #3 are qualified YES's, I'd like to hear suggestions about how to obtain them, if at all possible.

I'm in no rush to jump into this, and am proceeding with REW learning, opening one of them up to investigate the non-working 077, deoxiting, etc in the meantime.

Any and all thoughts are welcome and thanks so much for all the great JBL info I've gained here (and have ya'll to thank for the LSR305s and L5s I also have now!)

Thanks again....
Todd :)