[matthewpartrick]

Bought a functioning pair off eBay for not much, and they sound ehh.  There are some cosmetic issues I'm going to be fixing over the next few weeks, but I'm also looking for advice for changing out the drivers.  The tweeter domes are all messed up, and while I don't care about the cosmetics so much they're so banged up that they probably deserve a swap-out.  Same for the mids and the woofers. 

The question is:  Where's the best place to buy replacement parts?  The original speakers were 8 ohm resistance and the new ones are 4 ohms, so I guess it would be wise to stick with drivers that would jive with the crossover, or since the drivers are the resistance, does it really even matter?

They sell the cosmetic stuff practically everywhere eBay included, so the grills, stands, mdf veneer all not a problem.  The last time I restored a pair of speakers I was in high school 25 yrs ago so I need an applied physics lesson to make sure I buy the correct drivers.  Thanks in advance.

Matthew

[WGH]

My JBL L100's have been in daily use since 1972 and work perfectly, unless the drivers are damaged there is no need to replace them. People bought the L100 for their sound, flawed though it is with plenty of room for improvement, but if you "improve" the sound then the magic may be gone. If you change out the drivers then they will no longer be L100's, they will be something else in a L100 box

If the woofer and mid are damaged they can be re-coned. The original 1972 tweeter is a LE20-1, my manual say it can be replaced with a LE25-2 but it is not an exact acoustical replacement and should be used as a last resort. I replaced my original crossover, the new crossover is exactly the same as the old but with better caps and stuff.

Dennis Murphy, who designs the crossovers for Salk Speakers, also did a crossover mod for the L100, this page compares the Murphy mod to the Troels Gravesen crossover mod:
https://audionostalgia.co.uk/jbl-l100-crossover-upgrade/


I converted my L88 to L100 with a JBL LE5-2 midrange, which was offered as a kit in 1972.

[Wayner]

I don't recall the original L100 ever having an induction coil in it.

[Rusty Jefferson]

Actually, none of those drivers have recone kits available any longer.  They were all discontinued long ago. Second hand and NOS will be your options.

Be sure to visit Lansing Heritage. Lots of JBL info there. You'll have to join the forum to see the JBL Marketplace pages. (Items for sale)
http://www.audioheritage.org/vbulletin/

[WGH]

Lots of research will be needed, Google 123A-1 recone kit and parts are still available. Note the 123A-1 is run full range so testing individually without a crossover is no problem.

Genuine recone kit JBL C8R2212 for JBL 123A from JBL L100 Century and JBL L100 A Century speakers. The recone has the voice coil, spider, cone, braids, dustcap and glue. This is a genuine and completely assembled factory item ready to fit.  $605.77
https://www.speakerbits.com/index.php?option=com_virtuemart&page=shop.browse&category_id=1232&Itemid=146

[Rusty Jefferson]

   As I mentioned, only 2nd hand or NOS. Those (if there's actually more than 1) would be NOS. Only $1200 plus shipping. The kits from JBL are no longer available.
https://reconingspeakers.com/product/jbl-2212-c8r2212-recone-kit/

Got a link for the mid recone kits?

[matthewpartrick]

Good thoughts kids.

WGH, the mids and woofers may be ok if I refoam them, but the tweeters are shot.  There are NOS replacements on ebay and simply speakers that I might go with.  I'm also replacing the grill foam as it's shot and got some new stands that the fancy $4000 new JBLs sit on.  If the "crossovers" work well then I might leave them, but they seem like they're covered in cat hair  .  I'm also re-insulating both cabinets, placing a few buttresses inside to reduce resonance and running all new wire.

If you guys were running new wire, without going the Triode or Cardas pathway, what would be your next choice for internal wiring?

TIA.
Partrick

[WGH]

If you guys were running new wire, without going the Triode or Cardas pathway, what would be your next choice for internal wiring?

JBL didn't use foam on the 123A woofer or LE5-2 midrange, if yours has foam then I don't know what type of animal it is. Those re-coning kits are crazy expensive, I think the L100's were around $312 each in 1972 which is why I got the L88's for $186 each and added the mid-range when I could afford it.

I added internal bracing along with a sheet of 3/4" MDF on the recess in the back, routed out for the connections and knobs. The bracing really cleaned up the bass and the speakers clarity, made it more punchy too. I suggest adding a sheet or two of No Rez too while you have everything apart.

Definitely re-do the crossover, it's old, caps are shot too. Rewire with Kimber VS4 on the tweeter and midrange, and a double run on the woofer.

The L100 needs watts, 125 at the least with a high current amp, a Van Alstine amp would be excellent. A cheap solid state would be too shrieky in the midrange and treble because the L100's ain't that smooth up there.