Replacement diaphragm options for 2425J

To preface my question, after ten-years I was finally able to move my 4345s to my new home. Thankfully they are now in a climate-controlled environment but I fear their former high-humidity old (non-air-conditioned) house may have deteriorated one of the 2425s. I began to have a problem getting the HF of one channel to join the party without isolating it as much as possible and jacking up the volume until it would cut in. It did not seem to be related to the L-pad. Now I'm hearing a decided lack of volume and some distortion, compared to the other side. I intend to do a driver swap from left-to-right cabinet just to make sure it isn't the crossover or L-pad, but I'm fairly confident it's the driver.

If so, what is the best choice for replacement diaphragms for the 2425J? I hear frequent praise for Radians but would value more knowledgeable opinions and experience. For years I've heard that original JBL was the best choice, other then the price. I currently see what look like OE JBL replacements here. Are they authentic? Is the often-heard issue with Mexican-made JBL parts an issue about which I should be concerned? The price seems to be in line with Radians.

Anyone here in the business that can offer replacements directly to me? I understand there's nothing keeping authorized JBL dealers and repair facilities from selling diaphragms directly to consumers. Is that correct?

I'm 66 now and still working—six-days this week—so I'll get around to more diagnosis as time and the ability to disrupt the family living space allow. Getting the house-of-our-dreams built after 30-years of planning took close to two-years of my free and hobby time. Now I'm only working on a to-do list.

Thanks in advance for any advice or experiences.

I you got sound, the problem is most certainly mechanical. Dust, mould, spider web, etc. Carfully disassemble it and clean it, especially the magentic gap. There are probably youtube videos for how to do it.

Mårten

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Originally Posted by more10

I you got sound, the problem is most certainly mechanical. Dust, mould, spider web, etc. Carfully disassemble it and clean it, especially the magentic gap. There are probably youtube videos for how to do it.

Mårten

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Thanks. That was to be my first line of investigation after doing the left-right driver swap to isolate all else. Off to work today, though.

Congratulations on completing and getting into your new house. That's gotta be a great feeling.

I did try a pair of Radian aluminum diaphragms in my 2425h but ultimately preferred the titanium JBL diaphragms. I felt the upper midrange was better with the aluminum, but the titanium had better top end. My speakers don't have anything above the 2425, so I wanted the top end. With your speakers, the Radian might be a good choice. I'd send you mine to try but they're 8ohm.

Thanks for the offer!

Hi Phil,

RE: "... I fear their former high-humidity old (non-air-conditioned) house may have deteriorated one of the 2425s.

I intend to do a driver swap from left-to-right cabinet just to make sure it isn't the crossover or L-pad, but I'm fairly confident it's the driver."


I'd tend to keep the other failure modes under investigation until the exact cause(s) is/are found.

It looks to me that two drivers from a pair of speakers being in the same high-humidity environment are likely to develop the same issue with time, though it could be at a different stage on each one for now. Meaning if one has this failure for that reason, the other driver may also have the disease to some extent.

Used in the same conditions, why would one unit fail and not the other? Any differences that might explain this logically? (e.g. bad solder or wire, in addition to XO or L-Pad parts)

It seems like a good idea to open the other compression driver as well to assess the situation. After checking the other unit you might decide you need to purchase two diaphragms "while they last", in order to insure long-term peace of mind with the 2425s.

RE: Amazon/Simply Speakers link

I dealt with Simply Speakers twice, the last time about 10 days ago, they sent the right things in nice condition and service was fast with no hassles both times.

Richard

I have used the Radian diaphragm in both the 4425s and 4333s. It is a drop in replacement with no issues. The replacement JBL diaphragms that I have used are not exactly a drop in. They will require reaming of the locater hole. Also, the quality of the JBL diaphragms is questionable. I personally think the Radians are excellent sound wise. Per my ears anyway. I did ream a pair of JBL diaphragms for the 2405s in the 4333s. Tested with a frequency generator for rubbing of the V.C. They have been good for a couple of years now, but were a pain in the ass to install. One was bad, however the supplier that I got them from made good and sent a replacement.

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Originally Posted by RMC

I'd tend to keep the other failure modes under investigation until the exact cause(s) is/are found.

It looks to me that two drivers from a pair of speakers being in the same high-humidity environment are likely to develop the same issue with time, though it could be at a different stage on each one for now. Meaning if one has this failure for that reason, the other driver may also have the disease to some extent.

Used in the same conditions, why would one unit fail and not the other? Any differences that might explain this logically? (e.g. bad solder or wire, in addition to XO or L-Pad parts)

It seems like a good idea to open the other compression driver as well to assess the situation. After checking the other unit you might decide you need to purchase two diaphragms "while they last", in order to insure long-term peace of mind with the 2425s.

I dealt with Simply Speakers twice, the last time about 10 days ago, they sent the right things in nice condition and service was fast with no hassles both times.

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Thanks for the info on Simply Speakers. I still worry about the quality of the Mexican JBL replacements.

Of course I would replace both if I had to replace one. As for humidity, the one in the outside corner of the living room (closest to outside wall, etc.) was in a far more hostile environment. Hard to believe but easily recognized by the walls, floors, and other stuff in proximity.

Nice to hear the Radians could be a reasonable alternative.

Thanks

Phil,

RE: "I still worry about the quality of the Mexican JBL replacements."

JBL original part D16R2425 is $90. at Simply Speakers and made in low-cost Mexico...

Radian # 1225 diaphragm is $78. on their web site, 8 or 16 ohms, and made in the USA!

US made cheaper than Mexico manufacturing... Must be pretty fat margin on that Mexico stuff. Have I missed something here?

Richard

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Originally Posted by RMC

JBL original part D16R2425 is $90. at Simply Speakers and made in low-cost Mexico...

Radian # 1225 diaphragm is $78. on their web site, 8 or 16 ohms, and made in the USA!

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Yeah, I'm aware of all that—which is why I'm asking the question about manufacturing quality of the Mexican parts and comparative sound quality of the Radians! The decision is no longer to select Radian as a cheaper replacement, it now comes down to which is "better" in terms of quality of manufacture and characteristics of performance.

I'd probably be inclined to replace with the original but it's questionable whether or not the current replacement is equivalent to the original, anymore.

Thanks, all.

I have the Radians in Le85 drivers. I like them. Compared to titanium these should start breaking up att a higher frequency.

Hi Phil,

Its possible there is corrosion around the diaphragm screw down contacts in the faulty driver and or debris in the gap. When you get time have a look. The diaphragm may also require centring.

You might try Edgewood for the diaphragms.

If on inspection you find the driver needs TLC and were considering another pair of drivers l would talk to Jamin Jersey in CA. Their inventory has always been AAA in my experience.

http://jamminjersey.com/speakers/jbl/component

I have not personally used Radian diaphragms yet. On paper they are a drop in replacement. Being Aluminum alloy they will sound a bit different. Less shine or glow in the highs. But you might actually prefer them after a time.

Again, thanks for the advice and shared experiences. I plan on swapping left/right and, if it confirms my theory, take the faulty driver apart and document it here with pictures.

I have yet to have time for any diagnostic but I think I'm going to pull the trigger on the Radian diaphragms anyway, just for the heck of it and so I don't pull the drivers apart and not have them, if they're needed. The project will be quite the living-room disruption.

When I pull apart the 2425J should I find a foam plug there? Should I use one with the Radians? Felt? Otherwise?

Thanks!

I expect a gray one. If it remains resilient (possible but slim chance) and not compressed or gooey, why change it?

If not, and they were mine, I would use felt or replace with foam... JBL used to have the pads for the larger format drivers. Maybe worth a call to Pro. :dont-know:
At any rate, I'd put some absorbent material in there vs leaving it without. Will be interesting to get your impression of the difference, or if a clean out of one solves your issue :)

Probably foam, you can cut to size

https://reconingspeakers.com/product...45-damper-pad/

Rob:)

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Originally Posted by Robh3606

Probably foam, you can cut to size

https://reconingspeakers.com/product...45-damper-pad/

Rob:)

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Can probably get at least two from that :)

I sent an email to JBL Pro through the contact page on their website and got an answer back the next morning. I had Googled a part number for 2425 "Dampener Pad" and got JBL part number 61286. The JBL Pro customer service rep said it was a good number and they had four in-stock today. He gave me a phone number to call to place an order.

This afternoon I made that call and the rep was very quick to confirm the part and the price and asked if I had a Pro account. I said that I was just a JBL owner for the past 60-years but he gave me an account number and was very helpful in asking if they'd quoted me shipping costs. He then told me shipping was delayed these days but I told him I'd put this job off for years already and the parts' arrival would be my sign to actually complete the work. Total price for two "dampener pads-2425" including tax and shipping was . . . $13.80—or 80¢ more than the one pad shown in the Speaker Exchange link. Gotta love it when plan comes together!

Interesting that Pro is now in Richardson, TX and the parts will come from Arizona. I guess that's closer to the Mexican manufacturing facility. :dont-know:

:thmbsup:

They arrived today. Dimensionally they are 2-1/2" in diameter and 3/4" thick (63.5mm x 19mm).

Soon we can compare them to the originals!

https://live.staticflickr.com/65535/...9c9f9daa_c.jpg


https://live.staticflickr.com/65535/...0a36a61c_c.jpg

I wonder if they changed the formulation of the foam so it does not break down in 20 years... Strangely enough I had the impression my 2426 had a felt dampener, now I have a doubt it was maybe not original.

So, I had a little time today. Too hot to mow and I'd already helped a co-worker move a couch from a city 70-miles away.

Here's what I found when I removed and disassembled the right 2425J:

https://live.staticflickr.com/65535/...43fbfe45_c.jpg

And here's what it looked like all cleaned up with the new dampener pad installed:

https://live.staticflickr.com/65535/...8b5d6ca7_c.jpg

Shot a bit of Dioxit in the pots while I was inside. Tightened all terminals. Measured DCR in-spec.
I'll do some critical listening later but for now the initial reaction is it seems to be all well.

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Originally Posted by BMWCCA

I'll do some critical listening later but for now the initial reaction is it seems to be all well.

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:thmbsup: Gotta love it when a plan comes together.

Full-time maintenance on old stuff! Cars and speakers.

Now I realize I need new surrounds on the 2122Hs. So I placed an order through Rick Cobb and he immediately responded including picture of his (original) 4345s! How cool is that??

Pushing a dozen years that I've had these. Don't really know how old the surrounds are but New Zenith had re-coned different baskets with 2122H cones when Katz built them.

Like I really needed more projects! What I need is more time. :banghead:

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Originally Posted by BMWCCA

Like I really needed more projects! What I need is more time. :banghead:

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more time does not reduce the projects . I've had "more time" since 2002 and the projects seem to be expanding. Maybe it's just me, but I hear the same from many other folks in a similar position.

project lists seem to expand to fill available time. As my Dad once said "even if you buy bigger & bigger homes ...the junk will expand to fill them" :(

Hope your experience differs.

Pulled the first 2123/2122H today. Much easier than when I pulled the 2245. Had the heat-gun ready but didn't need it. Just slipped a thin putty knife underneath and it lifted right up. Removed the plastic trim ring and then the nasty glob that was the remainder of the factory surround. What a mess. Lots of Q-tips, alcohol, and X-acto blades. Now taking a break before fitting Rick Cobb's surround. Had to run down to the old house to find my 30Hz CD and to the store for a fresh bottle of Tacky Glue.

I have to work fast since laying a 4345 on its backside in the living room creates an obvious obstacle as well as temptation for the cat!
(The glass top fits nicely over the 2245 to protect it. Pillows will cover the other holes.)

https://live.staticflickr.com/65535/...7880a49d_c.jpg

https://live.staticflickr.com/65535/...5a962b16_c.jpg

Hi Phil,

RE "... the nasty glob that was the remainder of the factory surround. What a mess. Lots of Q-tips, alcohol, and X-acto blades."

Nice job you did!

In one of their refoaming videos Simply Speakers recommended using 91% alcohol for that job. I did. But can't say it had any magic nor was it a piece of cake. Still had to work a LOT to remove that crap on 2214 using lots of Q-tips as you did plus cotton rags.

The alcohol bottle seen on your pic seems like regular one 70%?? From your experiment do you feel it might have been easier for you if you had stronger (more concentrated) alcohol, i.e. felt yours lacking in solvent power??

Trying to determine if alcohol type used does really matter in terms of less effort or any will do just as well. Never used regular 70% acohol for this. Also, wondering if worth going out of one's way to get 91% though its not expensive?

Richard

On the topic of alcohol as a solvent, the type of alcohol also matters. The 70% and 91% alcohols that you get at the drugstore are both isopropyl alcohol. Denatured alcohol which is 95% ethanol is a more effective solvent when dissolving shellac and stripping some glue residues. I am not sure about this specific application, but it might be worth a try.

Unfortunately in the last year denatured alcohol has been banned in California. It should still be available in most other places though.


Widget

when cleaning old foam from a baskets edge, I used nail polish remover.
it's now much less potent than I remember , little smell , but kinda works. :crying:

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Originally Posted by Mr. Widget

On the topic of alcohol as a solvent, the type of alcohol also matters. The 70% and 91% alcohols that you get at the drugstore are both isopropyl alcohol. Denatured alcohol which is 95% ethanol is a more effective solvent when dissolving shellac and stripping some glue residues. I am not sure about this specific application, but it might be worth a try.

Unfortunately in the last year denatured alcohol has been banned in California. It should still be available in most other places though.


Widget

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I use the 190 proof Everclear (95% alcohol) to dissolve shellac. Smells a lot better than denatured - not sure if it's sold in CA, the 190 proof isn't even sold in all parts of TX.

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Originally Posted by RMC

The alcohol bottle seen on your pic seems like regular one 70%?? From your experiment do you feel it might have been easier for you if you had stronger (more concentrated) alcohol, i.e. felt yours lacking in solvent power??

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I used an old bottle I had around. It is 91% Isopropyl I've had it so long I think the price tag on it was something like 45¢! Can't really remember what I used the last time. Don't think it was alcohol but some other cleaner. The alcohol did a pretty good job and didn't require as much work as I remember when I did my L80Ts.

I actually used 3M adhesive remover for the rotted foam plug in the 2425J. Didn't try it on the 2122H, for some reason.

Not a lot of adjustment in the 2122H surrounds. Luckily they fit perfectly. Thanks to Rick Cobb for another success. Ran the 30Hz tone just for the heck of it, with no issues. There's just not a lot of room around this basket to fit the surround or glue in either step. Battery-charging the coil helped a little bit. I'm glad it's all over and not really in a hurry to do the other side just yet. No visible damage to that one and I'm not touching it until I'm ready to replace it.

I think when it's time do do the 18's, I might make a road trip to a pro. Any suggestions on the East Coast? Gordon W?

https://live.staticflickr.com/65535/...f119b012_c.jpg

Member here, OLDMICS runs Scavenger Sound (a pro sound company) near B'More and is a JBL agent. If that's not too far to go, he's been doing my surrounds and recone work for years . Recommended

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Originally Posted by rusty jefferson

Member here, OLDMICS runs Scavenger Sound (a pro sound company) near B'More and is a JBL agent. If that's not too far to go, he's been doing my surrounds and recone work for years . Recommended

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:thmbsup: Thanks.

When the time comes—and with enough advance communication—maybe he can even handle it while I wait.

I seem to have all my experience in 10-inch drivers. I still have six 12-inch to do, and two 14-inchers, too. Not sure I trust myself on the Eighteens!

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Originally Posted by BMWCCA

I seem to have all my experience in 10-inch drivers. I still have six 12-inch to do, and two 14-inchers, too. Not sure I trust myself on the Eighteens!

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I have never reconed any woofers, but I imagine the 18" woofers are a bit trickier than the 10-12" jobs... the 18s are also quite precious, though these days all vintage JBLs are becoming more and more precious!

Looking great BTW.


Widget

Attachment 87174


BEST lens "look" EVER!!!

Very Samuri !!!

:)

Okay, so I couldn't stop, and pulled the second 2425J to find the dampener pad pretty well disintegrated. Not as bad as the first one, but just as sticky. Still can't figure out how JBL can produce an adhesive that stays stuck forever while the foam deteriorates right on schedule. The hardest part is removing the adhesive film that sticks the pad to the back plate. All done now.

Next is the other 2122H. Might as well get it over with, but might have to wait for the weekend. I already filled this day-off with chores. And I had to drive the "new" car out into the country to find some local tomatoes. Summer just isn't Summer without a tomato sandwich on toasted oatmeal bread! Found some fresh-picked peaches and apple-cider donuts, too.

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I seem to have all my experience in 10-inch drivers. I still have six 12-inch to do, and two 14-inchers, too. Not sure I trust myself on the Eighteens!

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I have done a couple of pairs of 2235's and doing any of the long excursion drivers you have to be careful the coils are not tilted or they will seem fine until you give them some real excursion and they hit. As long as you exercise them well with the 30hz CD before everything set's you should be OK. If your not sure don't would be a shame mess them up.

Rob:)