PDA

View Full Version : JBL LE-14 surrounds



NikonSP
01-13-2011, 02:38 AM
I have bought a pair of JBL LE-14 recently, with the original yellow Lanceloy surrounds. Of course, these surrounds are very ready to be changed. My problem is, that a large number of different surrounds are offered on ebay!! Which one to pick???? Can any of you help me to pick the right ones??
Regards
NikonSP
Denmark

Fangio
01-13-2011, 03:55 AM
There are several versions of LE14A, with the lansaloy halfroll mounted in different ways by the factory, either inwards or outwards. It depends... maybe you could post a pic of yours to get appropriate advise.

NikonSP
01-13-2011, 04:11 AM
I'll get some pictures made later today and try to upload them :)

NikonSP
01-13-2011, 09:24 AM
I have made 6 pictures, but I'm only able to upload 5 in 1 go. If the 6th picture is important, I'll upload it later. :)

The 2 LE-14's have got the following serial numbers: #62163 & #62180

Please let me know, if you need further information and I'll do my best ;)

Regards
Harvey

Fangio
01-13-2011, 12:30 PM
Looking good, apart from the surrounds. Certainly worth to try and rescue the cones, as long as the spiders are still in a flat position, not too tired and sagging. Here is good info to read in some more recent threads, regarding the residue issue and with two suppliers mentioned

http://www.audioheritage.org/vbulletin/showthread.php?19773-LE-14A-surround

http://www.audioheritage.org/vbulletin/showthread.php?29440-LE14A-Surrounds


I did not try one of the european kit suppliers yet that I know of, most of them are being offered on eBay in Germany. In the thread below, they were repaired with new surrounds from looneytune2001 (http://shop.ebay.com/looneytune2001/m.html?_nkw=JBL&_sacat=0&_odkw=&_osacat=0&_trksid=p3911.c0.m270.l1313) as well

http://www.audioheritage.org/vbulletin/showthread.php?27684-LE-14A-surrounds

Rick can be contacted directly and is very helpful: rcobb at tampabay.rr.com

At the weekend I should receive a pair which I have bought the other day, with white cones. They are supposed to be reconed with factory kits, not refoamed, and with the surrounds attached to the back. Maybe I could post a pic or two for comparison.

Fangio
01-17-2011, 08:10 AM
Here they are, reconed with C8RLE14A kits.

Fangio
01-17-2011, 08:15 AM
Some more. The marks in pink are hard to catch, it says LE14A in the upper line.

DCR is 6.3-6.4 on both. Came in suitable JBL LE14x boxes for optimal transport protection. Not sure what a white C8RLE14A, H or H-1 factory recone kit would cost today, let alone two plus labor IF one can find them...

tomee
01-20-2011, 04:11 PM
...... In the thread below, they were repaired with new surrounds from looneytune2001 (http://shop.ebay.com/looneytune2001/m.html?_nkw=JBL&_sacat=0&_odkw=&_osacat=0&_trksid=p3911.c0.m270.l1313) as well

http://www.audioheritage.org/vbulletin/showthread.php?27684-LE-14A-surrounds

Rick can be contacted directly and is very helpful: rcobb at tampabay.rr.com

....

I can second the recommendation for surrounds from looneytune2001. I've repaired 4 LE14A woofers with R. Cobb's surrounds, and they fit perfectly. Carefully remove the old surround, and you can glue the new one on with the roll facing outwards and glued on the front of the cone. There are aftermarket recone kits, and maybe JBL is making new kits again but I don't know.

Fangio, those reconed LE14As look great!

Triumph Don
01-20-2011, 05:24 PM
I can second the recommendation for surrounds from looneytune2001. I've repaired 4 LE14A woofers with R. Cobb's surrounds, and they fit perfectly. Carefully remove the old surround, and you can glue the new one on with the roll facing outwards and glued on the front of the cone.

That is just wrong!

NikonSP
01-21-2011, 08:36 AM
Why is it just wrong??

hjames
01-21-2011, 08:45 AM
Why is it just wrong??
JBL speakers most often have surrounds on the back of the woofer cone.
In repairs, attaching to the front is usually done because its easier and quicker
than taking the time to properly clean the back of the speaker cone so you can glue the new foam to the back.
Plus using the front instead of the back creates a (minor) offset to the speaker coil.
:crying:
But most of all - front glued foams are UGLY!:D

NikonSP
01-21-2011, 09:18 AM
I see your point, - but still, the original surrounds on my LE-14s were glued to the front of the cones from JBL(ref. the pictures below) so in that respect, attaching new surrounds to the front of the cones wouldn't be different from the original method. Besides reglueing to the front, covers the area ealier used for glueing, and covering eventual damage to the plast material(from removing ealier surrounds), - but I don't know, - that's why I'm asking the forum :dont-know:

Which supplier and which surrounds would you use, if you were repair my 14's??

grumpy
01-21-2011, 09:23 AM
Unless I'm having extreme brain fade... didn't some of the LE14's have the lansalloy
glued to the front (as in the earlier pics in this thread, with the inverted surround roll
as well? If so, what is the problem with a front re-surround job on such a unit? (assuming
a properly designed new surround).

I imagine it would be quite difficult to get a clean enough edge on the aquaplas side,
when removing the lansalloy, to get a nice looking rear-cone surround attachment.

If I'm full of it, lemme know :)


Ah... apparently, I either do too much work between posts or I type too slowly.
... still would query Rick Cobb.

See Fangio's posted links, post #5 above.

speakerdave
01-22-2011, 12:18 PM
Yes, many of the original LE14A surrounds were glued to the front. I believe I have read here somewhere Rick Cobb saying that no one is making a surround for that particular installation these days and the one available usually needs to be glued to the front of necessity for appearance, as has been said. I don't think it's a big issue, myself.

tomee
01-25-2011, 11:08 AM
That is just wrong!

Well, the original surrounds were glued to the front, and removing them takes off some of the white coating. So, glueing them to the front is a nice way to cover your tracks. I plan to do one pair where I paint the cones after touching up the Lansalloy in spots and glue the surround to the back, just to see what happens. I bet they work as well as the others....

Of course a proper solution is a full recone. JBL used to do that for free under warantee back in the 70s and 80, and in that case the replacement cone had a foam surround glued to the back of the cone. All the original Lansalloy LE14s (and LE15s) I see on eBay and elsewhere have the surround glued to the front. If they were reconed by JBL then they will have the surround on the back or the cone, and I sometimes see these for sale on eBay too. This is for LE14A - LE14H, H1etc will be different.

The 4 LE14s I've done so far have measured BL of over 20, so no Alnico magnet loss, and Fs is within spec as well, so no floppy spider either. My theory is that the the stiff surround protects the spider from getting floppy, as can happen when a foam surround rots out and the speaker continues to get use after the surround has gone very soft.

Wagner
01-25-2011, 02:47 PM
I recently did a pair using Rick Cobb's surrounds.
The old was on the front, so that's where I put the new. (I solicited a few opinions along the way, Thanks!)
All I know is this: the part of the surround that attaches to the cone (with Rick's anyway) terminates precisely where the old Lansalloy did, so it's a perfect "fit".
The new compliance also lays in place perfectly on the horizontal plane, just touching the cone under it's own weight and disturbing the spider from it's FLAT rest position not at all.

It makes for a VERY handsome result, despite what some opinions indicate, very precise and clean looking.
Looks a Hell of a lot better on the front than the old stuff did.

Thomas

Wagner
01-25-2011, 03:09 PM
What does "BL" translate to in English?
I understand that it is the relationship between flux density and the amount of voice coil wire in the gap, but what do the letters actually stand for?
Or are they merely symbols?

Sorry for the slight derail.
Thomas

ratitifb
01-26-2011, 12:43 AM
What does "BL" translate to in English?
I understand that it is the relationship between flux density and the amount of voice coil wire in the gap, but what do the letters actually stand for?
Or are they merely symbols?

Sorry for the slight derail.
ThomasBL is the product of magnet field strength in the voice coil gap and the length of wire in the magnetic field, in tesla-metres (Tm).

Technically BL is known as the 'force factor' because the force on the coil imposed by the magnet is BL multiplied by the current through the coil. The higher the BL value, the larger the force generated by a given current flowing through the voice coil.

So a high BL figure indicates a very strong transducer that moves the cone with authority...

brutal
01-26-2011, 04:32 PM
Here's another rebuttal to the "that's just wrong" camp on THIS particular driver. If the lansalloy was front mounted, the replacement foam should be as well. The rule here is "as close to factory," not just a general "only on the back." These were done with Rick's surrounds.

http://www.audioheritage.org/vbulletin/showthread.php?469-Resurround-Step-by-step&p=197788&viewfull=1#post197788

http://www.audioheritage.org/vbulletin/attachment.php?attachmentid=30552&stc=1&d=1200714869
http://www.audioheritage.org/vbulletin/attachment.php?attachmentid=30553&stc=1&d=1200714875
http://www.audioheritage.org/vbulletin/attachment.php?attachmentid=30554&stc=1&d=1200714881

Wagner
01-27-2011, 09:07 AM
Here's another rebuttal to the "that's just wrong" camp on THIS particular driver. If the lansalloy was front mounted, the replacement foam should be as well. The rule here is "as close to factory," not just a general "only on the back." These were done with Rick's surrounds.

http://www.audioheritage.org/vbulletin/showthread.php?469-Resurround-Step-by-step&p=197788&viewfull=1#post197788

http://www.audioheritage.org/vbulletin/attachment.php?attachmentid=30552&stc=1&d=1200714869
http://www.audioheritage.org/vbulletin/attachment.php?attachmentid=30553&stc=1&d=1200714875
http://www.audioheritage.org/vbulletin/attachment.php?attachmentid=30554&stc=1&d=1200714881

Your work (and photos) were a big part of the inspiration to start doing my own JBL drivers, and for that, I thank you.
My results were ALMOST as nice as yours. My cones were in horrible shape from nicotine stains and yellowing.
I had to cheat a little; once I had the old surrounds removed, I masked everything and lightly fogged the white areas of the cone with the white primer using an airbrush.
Again though, as if you did not already know it, beautiful work!

Thomas