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DanMan
03-05-2007, 11:40 AM
Question about my L65's, and before you give me grief, lansing heritage automated email sent me my birthday greeting today.... so thanks and be kind ;-)

I bought these Jubal L65's on ebay long ago, so I'm way over the 30 day return policy... ;-)

It appears to me that the woofers were refoamed incorrectly - I added my comments in red in the pics below > I'm used to seeing my JBL woofer surrounds glued to the other side of the spacer onto the basket. (pardon if my terminology is incorrect).

Are these surrounds indeed on incorrectly?

The ohm meter shows 7.7 ohms across the woofer - what does that mean?

The speakers 'sound' 'ok' up to about 85db, but I wont turn it up louder than that in fear of harming either the speakers or the amp.

I bought these for the sound quality not quantity.

Am I in fact getting distortion throughout the volume range or only at the new peak excursion limits?

Is there a different mix of frequency response if they're on incorrectly?

Should they be refoamed?

Thanks.

Zilch
03-05-2007, 12:01 PM
Yes, they should be refoamed.

That's REALLY stupid what they did there. It's supposed to be UNDER the gasket at the edge, on the metal frame.

At the cone, it should be on the rear, but that takes effort by someone who knows what they are doing.

If the cone kit is available, have a full recone done by a pro.

You were screwed by an idiot.... :banghead:

SEAWOLF97
03-05-2007, 12:04 PM
they are wrong. I wud have them refoamed.

Z gave a better answer, while I was looking/typing.

grumpy
03-05-2007, 12:12 PM
ouch. clench your buttocks before pricing a recone... it would appear that an OK set
of L65's might go for about the price of a pair of recones for this driver. :blink: Think I'd be looking for either
a re-refoam (bastard side or not) or a functioning set of bass drivers that someone else
has pulled. Someone else check me on this. -grumpy

DanMan
03-05-2007, 03:07 PM
thanks guys. recone it is.

i guess that just leaves two questions that at this point are really more theoretical than functional -

1- Am I getting distortion throughout the volume range or only at the new peak excursion limits?

2 - Is there a different frequency response curve if they're on incorrectly (I'm assuming weaker in the bass region)?

grumpy
03-05-2007, 03:20 PM
thanks guys. recone it is.

i guess that just leaves two questions that at this point are really more theoretical than functional -

1- Am I getting distortion throughout the volume range or only at the new peak excursion limits?


almost certainly throughout... it appears you're already about 1/2 way out of the gap one way
(harmonic distortion, which you may or may not pick up as sounding "bad")



2 - Is there a different frequency response curve if they're on incorrectly (I'm assuming weaker in the bass region)?

I would -expect- so, and level dependent. One could look up studies on dynamic offset
for characteristics that would be mild in comparison.

Way to buck up for the recone... best way to go if these are keepers. -grumpy

Robh3606
03-05-2007, 03:27 PM
almost certainly... it appears you're already about 1/2 way out of the gap one way
(harmonic distortion, which you may or may not pick up as sounding "bad")


Hello Grumpy

You really don't know that as these are probably the wrong surrounds as well. The foams relative position has changed you need to look at the driver as a whole to determine what's actually going on. What you need to do is see where the spider is at rest. If it's flat he may not have as much of an offset issue as you would think.

Rob:)

grumpy
03-05-2007, 03:44 PM
Hello Grumpy

You really don't know that as these are probably the wrong surronds as well. The foams relative position has changed you need to look at the driver as a whole to determine what's actually going on. What you need to do is see where the spiders is at rest. If it's flat he may not have as much as an offset issue as you would think.

Rob:)

Good points, and true... I don't know about the surround history and going
from pictures is a bit of guesswork at best... a good spider is very likely to determine
cone position at rest with a soft surround.

Also true that it's way too easy for me to talk when it's someone else's $$$$.

-grumpy

mech986
03-05-2007, 04:29 PM
Wow, that's the screwiest resurround job, looks like one where the owner didn't even let the driver out of the cabinet or be unscrewed (although theoretically you could do a resurround in the cab).

Another option is to just purchase a new (to you) used pair of woofers that have th correct surrounds or can be resurrounded, might be a cheaper alternative. There has been some discussion of potential interchanges of woofers for the Jubal cabinet, do a search and see what your options might be.

Since a lot of L65/Jubals are being parted for the 077 tweeter, the correct woofers come up actually fairly often.

As for the current woofers, if the cosmetics aren't a huge issue, you could consider stripping off the incorrect surrounds off the cone and trim pieces and start over, could be a fun learning experience to correctly resurround these. If you need trim pieces, they are easily obtained as are the correct surrounds. The only problem will be a somewhat unsightly edge where the old glue was located, but that can be hidden from view with the grilles on.

Regards,

Bart

Zilch
03-05-2007, 05:02 PM
As for the current woofers, if the cosmetics aren't a huge issue, you could consider stripping off the incorrect surrounds off the cone and trim pieces and start over, could be a fun learning experience to correctly resurround these.
Good perspective Bart! :thmbsup:

edgewound
03-05-2007, 05:53 PM
Refoaming might be an option....if it's a JBL voice coil.

That's a definite hack job. Not only is the surround on top of the non-JBL gasket, it makes the voice coil forward-biased to jump out of the gap due to the fact that there can't possibly be equal travel in both directions of the cone/coil assembly.

The DC resistance is wrong too. What woofer is it? 126A, 122A or 129H

The DC resistance range of the 126A and 122A is 4.5-5.5 ohms dc. The 129H DC res is 5.3-6.1 ohms, so your voice coil is suspect.

C8R126A is no longer available, 122A and 129H both get reconed with C8R129H for $190.00ea.

Your woofers could be rebuilt with clean take-out JBL cone coil assemblies.

mech986
03-05-2007, 06:31 PM
Your woofers could be rebuilt with clean take-out JBL cone coil assemblies.

MMMMmm, JBL takeout, that's my kind of menu. Makes me hungry just thinking about it. :bouncy:

Good point about the voice coils, didn't even think about the fact these could be incorrect woofers or even really bad recone jobs with the wrong parts. As evidenced by the workmanship, anything could be possible here.

Regards,

Bart

Titanium Dome
03-05-2007, 07:18 PM
Look at the depth of the cone--or should I say lack of it? Doesn't it seem somewhat flat compared to normal?

I'd pull them out and get a good look at the spider before doing anything else. If it is pulled forward, then it's probably distorted for good, and recone is the only solution that still uses those frames.

Robh3606
03-05-2007, 08:25 PM
Here's a 122A

Rob:)

edgewound
03-06-2007, 05:57 PM
That fubar'd woofer is, in fact, a JBL factory cone.

The DC res is suspect in that maybe someone did some "fancy stealth surgery" by replacing the voice coil and reusing the intact cone/dustcap...

Hell...I dunno exactly what was done without seeing the guts of it....but it sure ain't right and it's not even pretty.

DanMan
03-07-2007, 01:00 PM
Thanks for the replies everyone. This has made me realize how fubar'd this situation really is. Details and guts to follow.

If anyone finds that that JBL takeout menu, I'll have one of everything! "better get a bucket" :D

Oh, and I must say in my defense, from the head-on pictures on ebay, i couldn't tell the gasket was on the wrong side, there were no angled pics to ascertain that (go figure) but the speakers really appeared in awesome condition and it was the best packing job ever. I should have stayed on the re-seller (an ebay store) but I lost contact so the fix $ must come from my wallet.

Ok, I pulled the woofers from the cabinets, judging from the pull force alone, they hadn't been off before (but shipment in the texas heat could have done that).

The driver is indeed a 126A from a Jubal L65 (pic #1). The spider does seem 'at rest' or completely horizontal (you can see it in pic #2). Ok, the 7.7 ohms really perplexed me. I tested that resistance numerous times b4 reporting it here and it really was 7.7 ohms. After testing it again and again I found that the resistance was changing based on the amount of pressure I used to hold the volt meter wires against the push-pin type wire connectors on the basket. Next thing I did was check the battery in the volt meter and it checks out fine. I didnt have any known resistors to test if the ohm meter was working correctly (it checks out on the ac/dc side of electricity) so I pulled woofers from L100T, L56, and L1's, and checked the resistance of those woofers - and they all check out to within specifications - regardless of how much force I use to hold the volt meter wires to the driver. So I tested the resistance again of the 126A's in 2 places (see pics) (A: at the push type connectors) and (B: at the Lshaped piece of metal that connects the wire to the cone). I get 7.7 ohms at point A and 5.5 ohms at point B. I dont see where I could be gaining that much resistance - the connectors are clean, look original,etc etc. If I mash the volt meter into the connector pins as hard as I can (without breaking them) the resistance drops from 7.7 to 5.5. Strange...

Knowing that the spider is at rest, but the surround seems placed incorrectly, I wanted to be able to determine the displacement of the cone vs the force required to displace, in both directions. As edgewound says "there cant possibly be equal travel in both directions", thats gotta have an odd impact on the sound characteristics. I dont have any real equipment here that checks cone displacement as a function of voltage or sheer force, so out of curiousity I had to devise my own method to check this.

Basically this involves using a laser attached to the cone to determine the change in distance as a function of voltage, in both directions. Pictures of this experiments below. Now, since the last terror alert was raised to crimson, I'm out of duct tape, but luckily I have scotch tape which is much lighter. Also my laser pointer is made from aircraft-grade aluminum so its lightweight, and the placeholder is balsa wood so the combination is very light weight, the tape is really used to hold the laser pointer button depressed during the experiment.

I used 2 C batteries together (around 3 volts) supplied to points A, and to points B, in the pics (the push type connector, versus the actual metal connected to the cone wire) in the positive and negative, whilst the laser pointed at the ruler in order to measure the cone's displacement.

Granted, this may be akin to holding a ruler to your monitor to measure distances, but if you're using a flat monitor, a good ruler, AND you have the image scaled on the screen correctly, its possible to get a measurement that may be semi-accurate relative to other similarly taken measurements..

Anyhow, it seemed to work well enough, and showed some interesting results:

At (A) the push type connectors (where I get 7.7 ohms):
+3 volts pushed the woofer out 3/30 of an inch
-3 volts pulled the woofer in 2/30 of an inch
Shouldn't they be the same distance?

At (B) the L-shaped cone wire connector (where I get 5.5 ohms):
+3 volts pushed the woofer out 4/30 of an inch
-3 volts pulled the woofer in 3/30 of an inch

The cone's different displacement (in vs. out) for the same applied voltage seems to me to indicate that the surround placement would indeed wreak havoc with the overall performance of the driver, (as well as the response of the entire speaker)?

Also, the push type connectors seem to have 2.2 ohms of internal resistance - that seems really odd - but the displacement experiment proves the resistance values. (granted i'm {also} bucking up for a more expensive volt meter soon.. )

Another issue I realized (and can be seen in the pics) is that the gasket is not manufactured to the same specs as the basket, so that the width of the gasket is not uniform along its length, meaning the surround, even sitting still, is deformed, and if its "out" bad enough, at volume, could deform the cone as well.

was 'fubar' the right word for this driver ?!?!

comments on the above are appreciated.. also beyond the technicals of all that, im still interested in salvaging the L65's and appreciate advice on what to do about getting the best woofer back into the cabinet - whatever that may be. thanks forum!

Hoerninger
03-07-2007, 01:13 PM
Basically this involves using a laser attached to the cone to determine the change in distance as a function of voltage, in both directions.

Thank you for the tip! :) Great things are easy.;)
____________
Peter

Zilch
03-07-2007, 01:15 PM
Buy the correct refoam kit from Rick Cobb and redo it yourself.

grumpy
03-07-2007, 02:30 PM
cool displacement test rig :) ... can't help thinking that some of the assymetry you're
seeing might be due to gravity and non-linearity of the existing foam surround,
as-installed (seeing that the gravity-assisted direction wasn't larger).
If you had a way to temporarily attach it to the cone (blu-tac?), you might be able to
separate the effects (for fun... ). Heck... blu-tac a small/lighter reflector on the cone and
measure the reflection motion...

I'd get some contact cleaner or "deoxit" into those terminals and work them a bit...
dissassemble if it's obvious how to. They should not add that much resistance to the
circuit.

FWIW, last place that I saw advertising 126A recones (which Edgewound found are
now NLA) wanted over $300/ea... part of my "clench" comment. If recones are
eventually required, you might want to run box simulations on the suggested cone
alternatives/substitutes.

-grumpy

mech986
03-07-2007, 05:55 PM
If the lead wires/tinsel is directly measured at 5.5 ohms, I'd say that is likely a true JBL voice coil. There is probably some corrosion at the wire/screw interface or there is a bad solder joint at the wire/solder ring spade connection. If it were me, I'd have a JBL authorized station replace the cnnectors with new gold plated binding posts and resolder a new ring spade to the lead wires or solder directly to the binding post. Once assembled, the binding post should be no more than 0.2 ohms above the lead wire measured directly.

Assuming the spider is mostly horizontal, I'd still opt for stripping the surround and frame trim off, check spider for condition and elasticitiy, and voice coil for centering. If all is well, I'd try refoaming correctly with the correct size foam/roll and properly placed on the cone backside. The slight cosmetic hit could be made up by salvaging a good cone. Heck, for the price of $25 worth of surrounds and some time, you're not into it for much and you can always recone if it doesn't work out.

BTW, nicely engineered optical displacement gauge you made. With the correct frequency, probably 70 hz or greater, you can easily measure the Xmax as a sort of Bar Graph Eye Tube like indicator display. I suspect though that the added mass is still making an impact though.

Regards,

Bart

DanMan
03-08-2007, 04:10 PM
thanks for the tips and the accolades on the displacement test 'rig'.

i dont normally touch or attach items to my JBL woofers - but the experiment sounded too good to pass up.

btw - the laser point makes a great instrument for aiming speakers in the right direction - i use the laser pointer attached to a t-square in order to get my surround sound speakers pointing exactly where i want em to.

the blu-tac sounds like it would be great for reflecting the laser pointer to the right spot if you're trying to bounce sound off walls in the right direction, and the deoxit also makes a great addition to my toolkit - thanks for the tips on those. i would have probably used wd-40 (just kidding) but 2.2 ohms seems like a huge loss to me - who knows maybe a bugs inside the terminal or something - thats what usually happens to our software ;-)

well while these all may sound like easy fixes to you guys - i'm really just a hack (as you can probably tell from my lack of proper terminology), a jbl nut for sure, but i'm a civil engineer, and i view my speakers as instruments, and i dont fix my own instruments, i leave that to the pros. so it sounds like these speakers need more tlc than i can give them. im currently involved in other projects (trying to get my own business into the big time) and i just dont have time for these.

honestly these jubals were my indication that i have a speaker addiction. i simply dont have room for these in my house. ive got jbl speakers in every corner of the house, that all work, and are all hooked up. i bought the jubals to replace my L100T's and while that may seem 'nuts' i was looking for the sound quality of the jubal (especially the tweets). but i missed my L100T's and putting them back in place means i have no where to put the jubals. i mean really no where. if you guys saw where the jubals are sitting now, id probably win some darwin award for the worst speaker placement ever! the L100T's were scheduled to go to my brother until he got his system going, but he's an idiot, and they're not going to be placed into his care. so i'm back to nowhere to place the jubals. i could store them but it would be years till im ready to work on them, and by then the parts would be even more scarce. (the jubals would have to be stored in a spare room - facing the wall - for protection - and it would just feel like i was constantly punishing someone that way ;-)

so for me the jubals are the speakers i couldnt have and it would just serve as a reminder that this jblnut went one overboard. im willing to sell them, probably not part them out, but just sell em whole. you guys now know what shape they're in - and the price would accomodate that - even though the rest of the speakers are almost near flawless - I'd say whoever originally owned em didnt do anything to them until the refoam, saw what job he got, and sold em to an ebay store.

if anyone is interested in making a good home for these i guess pm me as they say, or any other advise y'all have.. i will not ship these... so much trouble involved in shipping speakers correctly.. and i doubt i'd ebay them knowing the condition they're in, and my 100% feedback rating, and that i dont want to ship them. im in austin texas and you can pick up from my house or i could deliver anywhere in austin. i make the austin-houston journey every couple months and could deliver anywhere along the way (though these might not fit into my car)...

any (more) advice on selling these appreciated. thanks.

macaroonie
03-08-2007, 06:36 PM
Take your time and the advice and helping hand from the folks here. You will not regret it 65's are lovely.
:)

DanMan
03-08-2007, 07:17 PM
thanks. i love all my JBL speakers equally, i know that a space might one day open up for the jubals, and i'll probably regret selling them then. uh, change that, i'll probably regret selling them the day they're gone :o:

my dad has built some JBL speakers and I've seen him recone a lot, but i'm a little bit (ok, a lot) obsessive compulsive when it comes to symmetry, and so i've always had my recones done professionally for that reason.

i've accepted rubber when it was supposed to be foam, and vice versa, just because the parts weren't available, and its never worked out well enough.

i couldnt refoam, because i'd not be willing to suffer the cosmetic hit, guess im more ocd than i thought :nutz: . and a recone at 300 a pop is a notch more than i'd sell em for. even still, messing with the terminals would add to the price. i think fixin these is for someone other than me...

for me, the only acceptable solution would be the 128H-1 replacement. I know the 128H - I think that was a great driver. I see there's some 128H's now on ebay but again, i'm not putting a white cone in my jubals, i'm assuming the 128H-1 are the black coned versions of the 128H, am I right on this?

i see some other posts that suggest even with the 128H-1 replacement, i'd still need to modify the network, is this right? if not, i'll keep my eyes out for the 128H-1's and probably get two of them for the jubals as long as i dont have to mod the networks...

i havent seen a 128H-1 in a long time, anyone know what these go for?

grumpy
03-08-2007, 09:28 PM
hmm... if you go back to post #11 in this thread, I believe you might have
a few more options with fewer electrical and visual issues... -grumpy

here too (scroll back to check out the whole thread):
http://audioheritage.csdco.com/vbulletin/showpost.php?p=106493&postcount=16

guessing the suggested spacer gasket might be a bit shy of the thickness used on
yours, but ???

macaroonie
03-09-2007, 02:21 AM
For $30 you can refoam yourself. There is a great step by step thread here with pictures. As it stands that driver is a mess but it is anything but dead.
With a little care and some patience YOU can do it.
Worst case you mess up somewhat and are $30 out but it would be hard to have the drivers in as poor a condition as a result. All that old glue is easily removed with just a little care.
Trust me i'm a doktor...

coherent_guy
03-09-2007, 12:00 PM
Just came across this post and I couldn't resist. I'm glad you have pics of that butcher job, it should be in a hall of shame. I'm tempted to ask who the ePay'r is that sold those to you, but maybe they did not "fix" those woofers.

Please forgive me, but given that you have JBL's in every corner of the house and though characterize yourself as a hack (but came up with a nifty laser pointer excursion-o-meter) I find it kinda hard to believe you didn't take one look at those woofers and :banghead:

It did take nerve to ask about it on the forum although 99.99% of the members are very forgiving, I salute you for that :)

And who among us can say we were never surprised by what arrived via good old ePay. . .

I wish I had seen your pics about a year ago, I could of saved myself a lot of work refoaming my friends L65's. . . ;)

I'm sure your's will be good as new very soon :applaud: Consider, did you ever see the painted 077's I think T'Dome found out there somewhere? It could have been much worse :blink:

DanMan
03-09-2007, 02:09 PM
Well you guys are great. You've convinced me to give this a shot myself. Perhaps they still have a chance at finding a space in my home.

I dont want to give the ebay'er a bad name so I'm not saying who. I will say he's got around 2700 sales with 99.7% positive feedback, So hes 99.7% a good guy:) . He deals mostly in plates, im a bachelor, so i should say 'fine china' - and also vintage camera equip - all his stuff is near mint and even the plates (whatever..) go for +$300. Looks like fine vintage audio is maybe 5% of his sales or less. I seriously doubt he knew what was up - but who knows. I relooked at my old emails (im such a softee) that i never went after him.

I checked and I bought theses about 2 years ago - this was the 1st chance i've had at seriously looking at them for repairs - although i still dont currently have the time.

Yes, when the came i was flabergasted is putting it mildly. I knew i got what i deserved for putting the L100T's "facing against the wall" - it was their revenge :biting: against me!

You guys have been great consider the shape of these. Most of my time at this site is not in this forum - but reading it this week has been happily consuming. In the other forums I read daily, everyone is a genius, except everyone else who is an idiot. Statistically, I just dont see how its possible :D .

I found the resurround step-by-step links (you guys make it looks so easy) and cobb's ebay site. I know my dad will be 'over my shoulder' as i do this. Im opting for swapping out the binding posts to the gold ones. This will be my first JBL repair because even though these are minty (elsewise) theres some crackling in the control knobs. So hopefully forum is still as nice when i get back to reconditioning these puppies.

I need to learn how to effectively search these forums. And how do I get my picture under my username, it was showing up under my signature? (dont worry - i'll change the pic - it displeases me to see my L250's showing left on the right and right on the left)

c402c1
09-13-2007, 02:08 PM
:bouncy:What a great site. I got turned on to it by any ebayer that had bought a Rick Cobb kit. Fortunatly this just after I bought a pair of mint (exception of the woofer foam) L65 Jubals off ebay. I this knew when I bought them and figured I would have to drop $150 for refoaming. After poking around the site I feel very confident to purchase the items and do the work. So if anybody has any tips tricks I would welcome the input. What a wealth of information. I also have a pair of L100 Century that I bougth new 75 that I just love. Can't wait to get those Jubals going.

mech986
09-13-2007, 03:47 PM
Hi c402c1,

Welcome to Lansing Heritage! Hope you become a regular. Congrats on the Jubals, they'll be great after you get the woofers done. When you finish them, pop a few pics up and show us your handiwork. Remember to resize your pics to less than 1024 x 800 so they will upload.

Have fun, and if you need any help, just holler and someone will answer.

Regards,

Bart

mech986
09-13-2007, 03:53 PM
hi DanMan,

Did you ever get your refoams done? Inquiring minds want to know (and see!).

Bart

DanMan
09-19-2007, 12:19 PM
Hi. Yes I finished with the new surrounds, and since you asked for details... here they are...

I'll post my step by step instructions for future do it yourselfers ..

(I received the new surrounds from Rick Cobb and he was tremendously helpful with his instructions and all around nice guy.)

Well here's the way it went... to the best of my hazy recollection of the events that took place:

step 1. lay out all drivers, tools, and new parts
step 2. use xacto knife to cut into old surrounds, theres something i've never done to a speaker before....
step 3. after surround material is completely cut from the driver and basket gasket, start removing old surround from cone with xacto knife... start to realize that they must've used super glue (or some other inappropriate adhesive) as the surround material is more than extremely difficult to remove
step 4. switch to using dull tweezer to remove old surround from cone, the glue's so good that it starts to rip the cone material as it comes off with the cone
step 5. tap keg
step 6. pour first cold one, put on headlamp, and continue ripping off cone material with every tug of the tweezer
step 7. chug second beer, in order to dull the pain of the paper ripping sound the cone is making
step 8. continue tearing off surround and bits of cone material with tweezer eventually moving to super fine sandpaper to remove remaining surround
step 9. move barstool out of the way for better access to ashtray being filled with cone material
step 10. wince in pain as barstool slams into bare foot, at full speed, directly into the big toe
step 11. hobble around the house on one foot slapping self in face (in some strange pagan pain dance probably soon to show up on youtube) to more evenly distribute the pain
step 12. after the hobbling is done, muster enough courage to look down at toe and assess damage, surprised to see that the toe isnt damaged at all
step 13. look closer to find toenail was the only thing hit with barstool and is now lifted up at a 45 degree angle from the rest of the toe bed
step 14. hop over to sink for a cold water face splashing
step 15. wonder how come my jbl speakers were never as loud as the ringing noise in my ears, and also notice vision is nothing but white stars and can no longer see kitchen sink
step 16. oh i remember this from band camp in the hot sun... lie down so when I reawake I won't have a bump on my head to go along with the kinked toenail and torn woofer cones
step 17. wake up on the floor sometime later
step 18. push toenail back down 45 degrees till its flush with rest of gooey top part of the toe
step 19. call in hydrocodeine prescription
step 24. after a few days of beer and gauze, finish tearing off old surround and cone material from first driver
step 25. dont worry, i'm not including pictures of the toe
step 26. decide not to cut off old surround material from second driver and instead opt to cut only the conical surround section and leave the old surround glued onto the face of the cone, use the old surround material recut to shape and glue it back onto the first driver to cover up the ripped tweezed & sanded face of the first cone; this actually worked out quite nicely and covers up all my damages nearly perfectly and both drivers now look similarly fubared in a completely different way than original fubar.
step 27. finish gluing new surrounds to the basket and back of cones and all techniques as recommended by rick which all works out very nicely
step 28. finish and replace in cabinet
step 29. find another pair of 126A's on ebay and become the high bidder.

mission accomplished!

addendum - the toenail has come back in nicely since then (nearly 6 months now) the top half did die and come off, oh stop wincing, but the bottom half grew back nicely and you can hardly tell except for the demarcation line where it bent at 45 degrees which is nearly grown out now.

in hindsight, i wish i would've used my laser pointer displacement test rig affixed to the toenail to determine the true angle of lift, but i'm pretty sure it was nearly exactly 45 degrees...

overall, i would rate the experience 0 out of 10 stars

having a properly repaired pair of 126A's from ebay back in the cabinets... priceless!

DanMan
09-19-2007, 12:42 PM
obviously i don't recommend anyone following any of my footsteps in any of the above... ;)

c402c1
09-19-2007, 01:15 PM
Good point. I think when I do my 126A's next week I'll hold the homebrew to celebrate successful completion. However I will be checking for errant barstools though. I am fortunate in that my refoam job is subsequent to the original factory foams.

edgewound
09-19-2007, 01:17 PM
DanMan....

I hope you learned your lesson....

Drinking and drivers don't mix.

Funny story, though. Hope your toe heals up....no pics please.

JBL 4645
11-22-2007, 12:57 AM
Yes, they should be refoamed.

That's REALLY stupid what they did there. It's supposed to be UNDER the gasket at the edge, on the metal frame.

At the cone, it should be on the rear, but that takes effort by someone who knows what they are doing.

If the cone kit is available, have a full recone done by a pro.

You were screwed by an idiot.... :banghead:

Yes underneath the gasket whoa I wouldn’t be surprised if the (voice coil) is rubbing against the core, yikes. :eek:

markd51
11-22-2007, 09:02 AM
Hello Folks,
Sorry that I'm coming into this thread late, but I'd like to re-hash what's been written, and have some curious questions of my own.

Being an owner of four original L-65's since new, (You gurus know how long that is) my questions are, since the re-cone kit for the 126A Driver is no longer available, what options are there should one hypothetically blow a Driver?

An unlikely event that I'd blow a Driver, and most likely would need re-foam in the future. To inform all, my four 126A drivers were totally reconed twice in the past 34 years, never just re-foamed. They were done twice by authorized JBL repair centers, and thus as you all know, they would never just re-foam these Drivers.

So then, what would be one's option? Can the 126A be re-coned with another model # Re-cone Kit? If so, then what changes if any, are needed to be done to the X-Overs? (inductors-Caps-etc)

As you can see in my particular example, if a change would be needed to another driver, that would no doubt mean a minimum of at least both drivers in a pair, or perhaps even "times four".

Would I then have to convert to all different Drivers, L-65A, or L-65B drivers, which I assume it the 122A, or 129H? Or? Mark