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stupidhead
01-31-2014, 06:33 PM
Hello to all! I am new here on this forum and am looking for a little guidance. Today I came across a pair of L110's for pretty short money. Of course the woofers need to be refoamed and I have no experience in this chore. I don't think I want to use these potentially wonderful speakers as a training ground for such a task either. I live in southern New Hampshire, and am happy to travel 100 miles if need be to bring these to a qualified person. I have done some searching on the web, but I figure a forum like this will provide the best answer to this question. I do intend to rehab the cabs, and also the grill material has a few minor flaws, but the badges are both there, the frames are OK and I am looking forward to this project. Posting a few pics so you get a flavor of what I have here.
Thanx in advance.614216142261423

thanx in advance for any help!
Looking forward to participating in this community!

stupidhead
01-31-2014, 06:35 PM
The vinyl, if you were wondering, was also attained from the speaker seller. I am happy with this score for sure!:applaud:

wpod
02-01-2014, 05:09 AM
The L110s in my opinion , are a much more accurate speaker than it's bigger and more famous brother, the L100 Century. I am certain that you will like the sound of these speakers once they are repaired. There are a few authorized JBL dealers in Massachusetts , however unless things have changed, they may want to offer you a recone kit , which could cost a couple of hundered bucks each (if available). The more practical approach would be to buy a surround kit from Rick Cobb (looneytune2001) on Ebay and find a competent installer. I have bought several kits from Rick over the years and they are always a perfect fit. Something else you may want to do is verify that all three drivers in each speaker are passing signal, just don't apply too much volume as you could possibly dislodge the voice coil on the woofer if the surrounds are non-existant. If you can't find anyone close to you to do the recone , I could do it for you. PM me if you need assistance, I'm in Providence, RI. Paul

hjames
02-01-2014, 07:03 AM
The L110s in my opinion , are a much more accurate speaker than it's bigger and more famous brother, the L100 Century. I am certain that you will like the sound of these speakers once they are repaired. There are a few authorized JBL dealers in Massachusetts , however unless things have changed, they may want to offer you a recone kit , which could cost a couple of hundered bucks each (if available). The more practical approach would be to buy a surround kit from Rick Cobb (looneytune2001) on Ebay and find a competent installer. I have bought several kits from Rick over the years and they are always a perfect fit. Something else you may want to do is verify that all three drivers in each speaker are passing signal, just don't apply too much volume as you could possibly dislodge the voice coil on the woofer if the surrounds are non-existent. If you can't find anyone close to you to do the recone , I could do it for you. PM me if you need assistance, I'm in Providence, RI. Paul

And patience - Rick Cobb is very careful to make sure his customers have the best experience with his product.
That means no shipments to northern customers in winter when the glue might freeze in shipment or on your doorstep.

stupidhead
02-01-2014, 08:31 AM
Hi folks,

Thanx for the responses so far, and I will not be using these as my first venture into refoaming! I do want to learn this discipline however. I am also curious about the mids. They appear t be different and not sure if the pic I posted shows it but one is an innie and one is an outie (with some dimples). Is one or the other better/original/desirable/undesirable?

wpod
02-01-2014, 01:40 PM
the "innie" midrange looks to be an LE5-2, which would make it an older AlNiCo model of that midrange (my favorite). If memory serves me, the "correct" midrange for the L110 is the LE5-10, which is a ferrite magnet version. Without doing a search,I think that the LE5-2 is more effecient than the LE 5-10, but you could probably equalize with the L-pad on the mid. To be certain, carefully remove the two mids and examine the backs of them , they will probably be labeled as well. Let us know what you find. Paul ps- Google Images is great for identifying drivers, give it a try.

stupidhead
02-02-2014, 08:59 AM
Hello Paul et al,

So I have torn apart the first speaker. Serial 9584.61431
I have metered out all three drivers with good readings on all! Nice! 61432
Both pots spin freely and sound good. The board that holds the xover tells me somebody has been in here before. I don't really know what I am looking at here, 61433
but I am happy and willing to learn. What components on this board are suspect and what can be left alone. 61434
Are there any mods that can be made to better this speaker? Also, how about the cabs.61435
This appears to be a walnut veneer, but my sense is it is very thin material. Very thin!!! Of course I will want to restore these as best I can, so some insights on this would be greatly appreciated as well!

stupidhead
02-02-2014, 09:08 AM
Paul, you were spot on! Should I look for an LE5-2 to replace the 10? They seem to be readily available on the auction site, or is there a better resource?

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I am not necessarily committed to restoring these to be exact originals, unless that can't be bettered!

wpod
02-02-2014, 02:34 PM
If it were me, I would look for another LE 5-2, as I think it is a better looking, better sounding, and more effecient mid than all of the other variants (except 2105 which is the same). The LE 5-2 seem to sell for a higher price as well, but for what it is, I still think that it is a heck of a bargain. I would look on eBay to get an idea of what they are selling for these days, and perhaps post a "wanted "ad here on the Lansing Product MarketPlace.....Something else you might want to read: http://www.audioheritage.org/vbulletin/showthread.php?5706-The-LE5-Matrix . Regarding the stock L110 crossover , I think it is highly regarded as is (from a design perspective), however, I'd replace the stock capacitors with some film and foil type , as the originals are probably dried out and out of spec by now. The "white coffin" resistors are probably still OK, but check them with an ohm meter to be sure of thier value. I almost always replace those type of resistors with Mills MRA12 WW non-inductive resistors, but some people would consider this overkill in a crossover.I got into this habit from restoring old vacuum tube amplifiers . Inductors are probably fine as well and don't need replacing, but if you want to go crazy , copper foil air core is the way to go, but these get pricey as well. Keep up the good work and keep those pictures coming. Paul

stupidhead
02-02-2014, 03:57 PM
So I have taken apart the second cabinet, which was much easier than the first because now I knew what to expect. This one is serial 9781. These seem to be close in serial range, the numbers seem low-ish, is there a resource to tell vintage?
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So, a couple observations. The mid in fact is an LE5-9,
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not a 2! Looks like I may need to acquire a set of 2's. Both of these mids ohm out in the upper 6's if anybody needs them!
No surprises with the other two drivers and they check fine with my meter.
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I am encouraged already by this project, both woofers (while needing refoaming) are in good shape and the tweets have undimpled domes!
The cab on this one needs some attention as well, but that can wait.
The grille frame on this one is a little worse for the wear
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nothing that a little spray paint can't fix!

I will update this post as things proceed, but I need to finish up a pair of AR 4x's first.

Mr. Widget
02-02-2014, 04:43 PM
So, a couple observations. The mid in fact is an LE5-9, not a 2! Looks like I may need to acquire a set of 2's. Both of these mids ohm out in the upper 6's if anybody needs them! My recommendation is to avoid the temptation to out engineer the engineers who designed the system originally… I would look for another LE5-10 or two. These are the correct drivers for this design and will work best with your crossovers.

Any driver substitution will most likely not work as well even if the replacement is a theoretically superior driver… in this case, I don't think the LE5-2 is even that. It certainly cost more to produce, but the driver engineers at JBL generally do make improvements on their drivers even when they improve manufacturing efficiency. Not always of course, but in this case… I think you'd be adding distortion and losing a bit of neutrality.


Widget

wpod
02-02-2014, 05:16 PM
if the other mid was an LE5-2, I would have grabbed a second one and been done with it. I just have a love for this driver, stemming back from the early nineties? , when Bruce Edgar posted plans in Speaker Builder Magazine on how to build a wooden Tractrix Horn and how to couple a JBL LE 5-2 to it , for some of the most glorious midrange I had ever heard. He also used the Dynaudio D-54 midrange for the same application. I digress. In any case, grab youself a good used LE5-10 and keep that baby stock for now. You can always try the LE5-2 at a later date when the "upgrade bug" bites you. You'll be looking for 250 TIs or 4345s in no time!! Have fun!!! Paul

stupidhead
02-04-2014, 05:43 AM
Thanx for the responses folks. I have a few feelers out for a pair of 10's. Can anyone speak to the dimpling on the one I have, and the fact that it has a pinhole in the center.

Mr. Widget
02-04-2014, 08:15 AM
The pin hole may have been put there by a pinhead trying to fix it.... sorry, couldn't resist. ;)


Widget

stupidhead
02-04-2014, 09:08 AM
Good one Mr. Widget! I wondered about the origin of the hole as well. My gut tells me that the dome is compromised and should be discarded/replaced. Or does it not effect the performance? And the same question applies to the dimples, is it just aesthetic?

hjames
02-04-2014, 09:15 AM
Good one Mr. Widget! I wondered about the origin of the hole as well. My gut tells me that the dome is compromised and should be discarded/replaced. Or does it not effect the performance? And the same question applies to the dimples, is it just aesthetic?

Why not use a toothpick to apply just a small spot of glue to cover the pinhole?
probably best to put a matching dot on the same driver on the other speaker just so they are tonally weighted.

Maron Horonzakz
02-04-2014, 11:45 AM
good one mr. Widget! I wondered about the origin of the hole as well. My gut tells me that the dome is compromised and should be discarded/replaced. Or does it not effect the performance? And the same question applies to the dimples, is it just aesthetic? dimples are cute..

stupidhead
04-26-2014, 04:14 PM
So, two and a half months later here is the progress. I did order the surrounds from Rick Cobb, purchased a pair of LE5-6 mids from the bay and also a full compliment of Solen caps to redo the boards. Paul (wpod) graciously offered to walk me through the refoam process. This speaks to an aspect of this forum, and other related forums. The willingness of members to share knowledge, expertise and time with beginners is such a refreshing and encouraging aspect of this forum and has greatly enhanced my experience during this vintage audio rebirth I have been on! Thanx to one and all who have participated and especially Paul.
With that being said, after a few attempts to coordinate a time to visit Paul for the work, we finally came up with a mutually good date a few weeks ago, so Rhode trip on. The first pic here is of one of the patients with the replacement foam. Note the rubber retainer is still in place

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next, removal of the ring and cleaning of the previously glued surfaces

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and of course a dry fit is called for before anything to assure we have the appropriate materials

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and checking the backside for fit. Note the replacement matches up very closely with the old glue line. All signs are we have a good fit here!

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So now Paul's experience starts revealing itself. We take a hunk of foam rubber and wedge it between the cone and spider

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explanation of why and more pics to follow after dinner. Mrs. Stupidhead has made a fabulous smelling potroast and it is ready!

stupidhead
04-27-2014, 03:59 AM
Wow, that pot roast was awesome. Now, back to this post.

The foam acts as a bumper and wedges the cone into a higher position than normal, making it easier to glue under the cone and on the surround, and other manipulations during this part of the procedure. In this picture which was taken later in the process, you can see the cone extended above the frame from the foam bumper.

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This gap created from the foam also allows for better access to the back side of the cone and you are not constantly having to peel back the surround.

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after making some adjustments and cleaning any excess glue, we have a newly glued surround, at least on the inner edge! Time to let these sit and cure for a while!

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