View Full Version : JBL 115H Driver Coil open and smached

10-09-2008, 11:24 AM

I got for free 2 very nice L15(?) / ProVersion = 4401

Both Drivers have rotten Surrounds.
The Old Guy have drive them anyway. :banghead::banghead::banghead:

So, now on the first the Coil is not damaged, only the Paper Tube Edge
is a bit pushed hard. Rolling Ends. Not a big Issue, (I think).

The second Warrior is comming back with broken Wing ..
- Coil pulled from the Coil-paper-Tube, scratching, broken.
- only the 3 last Windings - Winding #3 from Top is broken

I have removed the whole Cone with Spider, desoldering the Wires from the
Tap's - Looking not so bad - but, have cut a bit in the Spider Edge.

When speaking about Spider Dimensions, what's the Measure-Naming?
Inner Circle, the Hole, or the Outer Diameter??

Are the worth for Repair??
The Wood and Covers, like the Tweeter are in pristine Shape.

Is there a Cone-Kit with Spider outthere in the Wide of Marketplace?

I have repaired many Speaker Types, like JBL, Yamaha, Onkyo, Dynaudio, Lowther (:biting:)

For any Help I would very apreciate!

Best Regards,

10-09-2008, 12:13 PM
Try to find a donor pair of L15 with nasty boxes and rotten foam but good coils ????

10-09-2008, 12:47 PM

very good scottish Humor ->:blah::blah::blah:

:D - its ok, I see You!

The other Old Guy No.2. have only one big 431x something.
I pass. Too big :p for lifting, like Horns ... :p

In a Chance 15237598374709 : 1, its possible to find the invers Ones.
But Hey, here in middle-East-south-south-Nord-Center-Europe, You know,
the JBLs are pretty RARE!!! (and.. iam FSE in LFP for GSP! )

Its already a big Bonus-to Todays Find. Each 10'000 Y. You have a Chnace here for that Kind of Deal.

He need another Pair in same Dimensions. Surprise: I got a Pair of L16 Decade - He would pay 350.-Sfr. its about 330$US..
allready reconed with new Surrounds from a very good Quality.

My biggest P.I.T.A. was this PM6C from Lowthers.
What a nice little Air Gap for the VC.
Aligned with 330Hz, perfect - going deeper to 63Hz, : Scratching!

So, how's Life in the upper Midlands?
Here at Zürich, we have nice warm 19°C Today.
Good for JBL Speaker Trading :bouncy:

Best Regards,

10-09-2008, 01:34 PM
As far as I know there are no more cone kits for these ( C8R115H ) although you could try the various JBL distributors across europe. One of the forum members here might have a trashed cone with a good coil. There are a few professional repairers here. Put up a post in the product marketplace. Good luck.
Oh 13 deg and raining as usual:barf:

10-11-2008, 09:56 AM
Good After Noon, Sir Roonie!

Thank You for the good Input.

Iam very handy (:p) - I will repair this Guys, Iam shure I can do.
Have some nice Skills - Iam from Switzerland. There are a lot of
Tinny-Small Tools for all Purposes. Think about Swatches, Microelectronics etc. etc. If I need Some Special Tipps, Tools, whatever, there are here.

PLUS: Iam a very patient Guy! I can wait Years, if necessary.
Its more a Passion, then a Hobby, like Fishing - You know what I mean.

So the First Thing I need is to DE-ISOLATE the thinny Wire Ends of the broken Coil. I will not Rush.
As all Voice Coils, they are isolated with a dark-orange Insulation coating.
Mechanical isnt reely good. I could destroy, or bend more than necessary.

Whit Heat the Copper will more become harder and maybe changing the electrical Resistance a bit.

So, I feel, that only Chemicals can do a good De-Isolation Job here.
I need only 0,6 - 0,8mm blank Copper Ends for Soldering under the Microscope.

What are common Applications?

Best Regards,

10-11-2008, 02:24 PM
Guys, I did-it!

1. Scrapped only from ONE SIDE the Laquer Isolation off, to become a nice small Contact Area.
2. Soldered with my finest Pin Point Solder Pin.
3. Aligned all 3 Windnings in the right Position
4. Glued with Cyanolit Glue, only a few Tips
5. Meausured the Impedance, 4,3 Ohm (the Leadwires had 0,4 Ohm)
6. Glued so, that the fine Liquid Cyanolyt is going in to the fine Gaps
between all last 4-5 Windings

Also did:

a) Sticked some 3M Tape over the VC Gap, to avoid Contamination
b) Scrapped off all old Surrround Coats with the Old hard Glue.
c) Fixed the little Cut in the Spider outer Edge
d) Cleaned the Driver Chassis with compressed Air
e) removed the Scotch Tape from the VC Gap
f) cleaned, skinned the underneath old Glue from the Cone Edge
g) Drink a fine Coffee and smoke one Parisienne Jaune
h) Removed the Dust Cap for Centering the Cone
i) Insert the Cone in the Chassis, Voise Coil in the Gap - fits perfect
j) Shimms for Centering "injected"
k) Glued the Spider on the cleaned Basket

Tomorrow will come the next steps:applaud: