Got a old pair of 4425, damaged... Can they be revived?

[MGV101]

My family has a pair of JBL 4425 at home purchased 10+ years ago that were rarely used. I am trying to build a home theater system myself and after finding out how nice these speakers were, I was planning to put them back into use.

After removing the font grill, this meets the eyes (see attached picture)... the foam seal around the cone seemed to have rotted away and crumbles on touch. Will this have any significant impact on the speaker themselves?? or it is OK. If it is not, is there anyway to fix it? It's sad to see such nice speakers go to waste.

I have yet to connect up my system in fear of causing more damage so I cannot test them.

While searching around this forum, I have heard someone mentioned the word refoaming in this post http://www.audioheritage.org/vbulletin/showthread.php?t=14283&highlight=4425 while searching in this form. Is this what I need to do for my speakers?

Thank you.

[sourceoneaudio]

MGV101
Well that's one hell of a find/gift. There are foruum members that can help you one, I believe is Edgewound.

Here is also a link to a re-foamer out of Cali.

http://www.speakerrepair.com/


You will have to pull the drivers and ship them, make sure to double box them so they don't get damaged.

Also here is another set for you to use on your rear channel.

http://cls.audiogon.com/cgi-bin/cls.pl?spkrmoni&1179187901

Good luck and enjoy the music.

P.S. Don't play them in that condition. After pulling the woofers you could hook them up to test the HF driver, just don't let the unhooked leads touch while testing.

J/S-S1A :applaud:

[MGV101]

cool, glad to hear they could still be repaired.

Thank you for the link but unfortunately I do not live in the states and shipping those drivers all the way to the states might not be that economical.

I'll see if I could get these repaired locally first. If not, I'll just have to order the kit from that site you've linked and pray that I do not mess things up while at it.

[hjames]

cool, glad to hear they could still be repaired.

Thank you for the link but unfortunately I do not live in the states and shipping those drivers all the way to the states might not be that economical.

I'll see if I could get these repaired locally first. If not, I'll just have to order the kit from that site you've linked and pray that I do not mess things up while at it.

I got an old subwoofer in Feb and the foam surround looked cracked and crumbling like yours does. The folks here recommended a guy on ebay who sells replacement speaker surround foam kits

You need to find out what drivers are in your speakers, then order a pair of new surrounds. If you are reasonably handy, are willing to follow directions and be careful with your speakers, its not that hard to replace the surrounds - which is what that foam area is called.

Contact Rick Cobb (looneytune2001 on eBay, and at [email protected]) - His kit helped me fix my woofer!

Here is a thread showing the basic process on some smaller drivers:
http://audioheritage.csdco.com/vbulletin/showthread.php?t=469&page=2

Here is a link to before and after pictures of my woofer:
http://audioheritage.org/vbulletin/showpost.php?p=150406&postcount=17

Good luck!!

[Chris Brown]

Yeah, the foam thing is pretty normal for speakers that old. When I first got my L150's home, I was happy that the foam was still intact after all those years. Unfortunately the instant I put on some music the foam blew right off of the speakers! (I guess because the L150's are a sealed cabinet)

[Titanium Dome]

On this page you will find two authorized JBL service stations in Hong Kong that might be able to help you. Especially if you don't want to do the refoam yourself, they may have the facilities to do it for you.

http://jbl.com/home/product_support/int_service.aspx?product=4428&Language=ENG&Country=HK&Region=ASIA

Once the woofers are refoamed, those 4425s will be very nice for you.

BTW, good instincts on not driving them with rotten foam. That could ruin the voice coils and require a complete recone or replacement.

[johnaec]

Just be sure the foam surrounds are installed correctly on the BACK side of the cone. Some places take the easy way out and glue them to the front...

John

[MGV101]

grr... I was planning to glue those surround onto the front of the cone after reading the instructions for the surround kits sold at orange county. Guess I'll have to do it the hard way then.

oh, and thank you to everyone who had posted here for their help!

[John]

I have performed about a half dozen pairs of refoams and always glued to back of cone. I think that is the easy way of doing it. I am not sure how attaching it to the front of cone makes it easier??? I would think it would be harder??? When glueing to back of cone it seems to be easy to keep everything lined up as far as foam to cone goes.:blink:

[hjames]

grr... I was planning to glue those surround onto the front of the cone after reading the instructions for the surround kits sold at orange county. Guess I'll have to do it the hard way then.

oh, and thank you to everyone who had posted here for their help!

When I rebuilt my 2235H I glued the surround to the back - it takes a bit more time, but its really not hard to do it right. The payoff is better sound, and knowing your speaker is done right.
If the speaker surround wasn't glued to the front before, doing so now changes the way the cone sets at rest, and that can affect the way it works. But the speaker rebuilders in the list here can tell you more about that better than I can. If you can do it right, why do anything different?

[johnaec]

When glueing to back of cone it seems to be easy to keep everything lined up as far as foam to cone goes.:blink:I agree! Plus, you don't risk the chance of smearing glue on the front of the cones!

John

[jbl]

Mgv101,
Where were those speakers stored? I believe that Hong Kong is a humid environment. Your speakers appear to have been stored in a dry, hot area of the house. That's the reason I never use the heat in winter in the audio room. It would dry everything out. I keep the windows colsed on the coldest days.
While you have the woofers out, it would be a good idea to check the condition of the wires. The rubber insulation may be dried as well.

Ron

[RKLee]

Mgv101,
Where were those speakers stored? I believe that Hong Kong is a humid environment. Your speakers appear to have been stored in a dry, hot area of the house. That's the reason I never use the heat in winter in the audio room. It would dry everything out. I keep the windows colsed on the coldest days.
.
.
Ron
Gosh Ron, that is bit extreme isn't it. I think the foam surround will only last a bit longer, beside if you refoam your speakers, they will good for another 10 years or so, and you will have refoam them again regardless of the room temps.
Ron

[mech986]

grr... I was planning to glue those surround onto the front of the cone after reading the instructions for the surround kits sold at orange county. Guess I'll have to do it the hard way then.

oh, and thank you to everyone who had posted here for their help!

Hi MGV101,

How did the resurrounding go on your 4425's? Did you also do any refinishing on the cabinets? Let us know and post some pics on your handiwork. I'm sure it went well.

Regards,

Bart