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pioneer
03-02-2006, 07:37 PM
I pulled the drivers to check serial numbers on my recently purchased L300's . Upon inspection I found these two tiny holes just outside of the dustcaps ( hopefully you can see in the picture if my attachment works). They look like they were used for the wires that attach to the cones but maybe put in the wrong spot? it leads to two questions is their anything I can put on to cover them or should I leave them as is. They do not seem to be growing. Part two I was told that these are the wrong dust caps does that effect the woofers? I did a search on the site but I could not find anything in the archives although I am sure this has been asked before.
Thanks

jim campbell
03-02-2006, 07:42 PM
howz about a pic of those surrounds

pioneer
03-02-2006, 07:57 PM
here it is

57BELAIRE
03-03-2006, 09:36 AM
Here's a pic of my 136 and it does look like your dustcap might be a tad larger.

The distance from the edge of the cap to the first set of concentric rings is
1 1/4 inches also, the two leads are clearly visible.

edgewound
03-03-2006, 09:56 AM
here it is

Aftermarket recone, looks like

pioneer
03-03-2006, 10:02 AM
I was told they were reconed when I bought them and supposedly by an authorized jbl dealer but I am not so sure about that.The back of the cone has W5777108 stamped on it. The leads are not visible on the cones they are covered by the cap and on the one I took the picture of shows two tiny holes were it looks like leads had been planned but not finished.

edgewound
03-03-2006, 10:07 AM
Definitely aftermarket recone...I hate the misrepresention.:banghead:
It's just wrong.

pioneer
03-03-2006, 10:16 AM
that's the problem when you deal with long distance and have to trust the seller. although in this case the seller was only a middle man and was passing on what the original owner had told him , they did look like they were reconed in the picture with oversized caps. So they question is leave them alone fix the holes , look for replacement or recone these

Robh3606
03-03-2006, 10:38 AM
Well the number one question is how do they sound??? You know you have after market kits so to recone you end-up with 2235's as the 2231's are long gone. With the after market kits you really don't know what you have. Is the mass ring installed?? Who knows??

Rob:)

pioneer
03-03-2006, 11:08 AM
They actually sound pretty good. Without hearing another pair I am not sure if I am missing anything. Will an after market cone be bad, although hearing this makes want to recone or replace. Mass rings hmm!!!! good question since I do not know what I am looking for I will have to do some searching.
How much difference does the 2235 make in the sound compared to the original 136a or is this one of those personal preference questions.

majick47
03-04-2006, 04:06 PM
Pioneer if you decide to have the 136a reconed and done correctly contact John at Pro Sound, Braintree MA, a JBL Pro shop.

pioneer
03-04-2006, 06:51 PM
Hi Majick47
I called Braintree yesterday and they quoted $140 to recone to the 2235. Did you use them? He would let me preorder the cones(which he does not stock) and notify me when they came in and turn them around in two days.I also called a JBL pro dealer up in Stoneham who quoted me $109 which is a good price but is a shlepp to go up there and I do not know the quality of their work. I tried the dealer you mentioned in Hanson but I did not hear back from them yet.

majick47
03-05-2006, 12:30 AM
Pioneer Pro Sound Braintree reconed two pairs of 136a for me and both were very well done, the price sounds like what I payed. At this time Pro Sound is refoaming a pair of 116h for my 4301b. Stoneham would be a hike for me also. One pair of 136a had been reconed prior to my purchaseing them by a shop on the North Shore, can't remember if it was in Stoneham, the reconeing was very poorly done. I havn't done buisness with the shop in Hanson so I can't give you any recommendation re their workmanship. I remember calling them once and they said they mostly did work on cinema systems.

pioneer
03-05-2006, 07:59 AM
thanks for the reply....I assume you reconed to 2235's did you notice a difference in sound from the original 136a's? not that I have a choice if reconing, unless I can find a used pair of 136a's for sale in good condition

majick47
03-05-2006, 04:26 PM
Pioneer my L300 came with 136a woofers with the original cones and they had been refoamed correctly shortly before I purchased them. My L200b with the 136a woofers reconed with 2235a cones sounded the same to me as the L300 136a with original cones. In fact I tried a pair of 2235h woofers in the L300 for a while and still heard no measurable difference. Some members with better hearing and experience may be able to distinguish the different 15" woofers but so far I havn't been able to do so. I'm confident that you will be very happy with the results after you have the 136a reconed with 2235h cones. Like you I want to keep my L300 "original" as possible. If you check the product brochure the recommended available recone for the 136a is the 2235h cone and by this time many L300 will have been reconed with the 2235h.

pioneer
03-23-2006, 11:27 AM
It turns out the cones were definetly after market and were missing the mass rings. The depth of the voice coil windings were roughly a half inch to short and were starting to rub. The adhesive job was very messy as pointed out by John at Pro Sound in Braintree Ma.(very pleasant to deal wth). The extra holes on the aftermarket cones we cannot figure out why other than maybe they had uses with other drivers but they looked like they were put in by the manufacturer and were only on one cone.
All in all I am pumped to get them back on Saturday morning to finally hear what the L300's are really suppose to sound like.
Thanks all for the help, The experience on this board is amazing. Members were able to pin point the problem without ever hearing the drivers and looking at digital pictures. Hats off!!!

edgewound
03-23-2006, 12:32 PM
Glad to help:)

remusr
03-23-2006, 12:59 PM
Note that the 136A/2231A's have 1 step softer spiders than the 2235H's so make sure you get the right ones - probably the main difference between the 16 and 20Hz Fs's. If you are installing OEM JBL 2235H cones you don't have much choice but aftermarket kits are assembled and the installer can customize to tweak the sound to be more original.
PS - why are you doing this again - the 2 holes could have been sealed easily and I doubt the larger dustcap would audibly affect bass, probably only slight affect on dispersion of mids.
- Roy

pioneer
03-23-2006, 01:14 PM
I am having it reconed by a JBL pro Dealer with JBL 2235 cones. The holes were a concern but after looking at them closely they were not going to be a problem as they had tiny metal eyelets around them they would have stopped them from tearing(why they are there is a mystery).
The real reason was my old L100's had better low end response than the L300's.That I knew was wrong. Until we took apart the after market cone on the 136a and saw the lack of mass rings that answered part of the reason why I lacked the low end. I will know for definite saturday when I get them back. The other reason was that I wanted to restore them as close to the factory sound as I could.

edgewound
03-23-2006, 01:22 PM
As you can see....the aftermarket reconer screwed this up because he couldn't get the genuine recone kit, which for a 2231 is a C8R2235, and he couldn't even do the aftermarket job right.

Congrats, Pioneer, on giving your L300's the care and feeding that they deserve with available factory parts....now they should be done right.:applaud:

John
03-23-2006, 03:48 PM
The reason the two holes were there is because someone was going to use them to run the leads thru, but then it seems there was a change of direction???:banghead:

Zilch
03-23-2006, 05:52 PM
Sometimes, it's not the reconer:

"What's the cheapest way you can get these working so's I can unload them on eBay, Dood?"

Robh3606
03-23-2006, 07:15 PM
It's good you will be getting proper kits. Let us know what you think when you get them back together.

Rob:)

pioneer
03-25-2006, 01:17 PM
I just reinstalled the newly reconed 136a's to the 2235's into the L300's. Initial impression is "wow what a difference" from the old aftermarket kits I was stuck with, money well spent.
Unfortunately I did not have any choice in staying with the 136a as mine were long gone and I could not locate another pair of 136a's, even if I did find them I am not sure that I would not have had to recone them anyways.
The bass is now incredible, much crisper, fuller and deeper sounding . This is what I thought I was originally getting. From what I read here as they break in it will get even better especially when I add the Mcintosh MC2500 later this week.
Since I have nothing to compare on the old I do not hear a loss in the midrange but my guess is you have listened to your 4333 at lot longer then me and would be able to pick out that kind of change.

Edit: the part in this about the reconing of a 136a to a 2235 was in answer to Speakerdave who posted on this thread then moved it to it's own thread. He has the 4333 that he feels lost midrange when he reconed a 2231 to a 2235. If I could figure how to link it I would

speakerdave
03-29-2006, 11:18 PM
Since I have nothing to compare on the old I do not hear a loss in the midrange but my guess is you have listened to your 4333 at lot longer then me and would be able to pick out that kind of change.

Edit: the part in this about the reconing of a 136a to a 2235 was in answer to Speakerdave who posted on this thread then moved it to it's own thread. He has the 4333 that he feels lost midrange when he reconed a 2231 to a 2235. If I could figure how to link it I would

I just saw this. Thanks for the note. I agree with you about the bass. I'm still investigating what is happening with the lower mids. My 2231's are back in for now. I'm glad you have a solution for your L300's. I think the L300/4333 are very enjoyable speakers.

David

GordonW
03-30-2006, 03:16 PM
I just saw this. Thanks for the note. I agree with you about the bass. I'm still investigating what is happening with the lower mids. My 2231's are back in for now. I'm glad you have a solution for your L300's. I think the L300/4333 are very enjoyable speakers.

David

Any way you can have someone measure the parameters of the "offending" 2235s? If the moving mass is too high, then this type of behaviour can be expected. Testing the woofer with something like the Woofer Tester II (from Parts Express) or something along that line, can determine the effective moving mass (and therefore, the mid-band efficiency, in the midrange).

Also, it might have something to do with the fact that JBL now seems to be supplying a larger (4 7/16" roughly, as opposed to the old 4 1/8") dustcap on recent 2235 recone kits. Could be less dustcap "coupling" to the cap, which might result in less mids...

Regards,
Gordon.


Regards,
Gordon.