4315 woofer, please help

[snoopy751]

Hello all,
I have bought recently a pair of JBL4315 from eBay, the speakers arrived yesterday, however, one of the woofer 2203A has a problem with no sound.

I took it out and swapped with the another 4315 woofer, which has no problem, meaning the crossover of the speakers are normal.

I used a multi meter to test the impedance of the woofer, and the reading is normal, however, when I use a 9w battery, it has a static sound but the cone does not pop in/out as the another one.

Now my questions :

1. Can this woofer be repaired e.g. by reconing ? As people said it can, but how about it is not the wire of the cone blow up?

2. Is there any replacement of this 2203A (some said 2202H can fit), I do not mind to replace both woofers at the same time, even sound quality is not as good as the original

Thank you

[bldozier]

I read the 2202a/h does not go as low as the
2203, however can accept 2203 cones. If you can find
a voice coil or have a custom wound coil, you should
be allowed to save your original cone, with an updated
coil. The 124a Can be used. The 2204 may need a cone kit
Can you post pictures mate.

http://www.audioheritage.org/vbullet...highlight=124a

[Don C]

I have had a couple of speakers that had close to normal resistance, but made no sound. They were LE5-2s. It turned out that the voice coil wire was not fastened to the coil formers, probably because heat had damaged the glue. It's also always possible that the magnets have no magnetism left.

[gibber]

Hello all,
I have bought recently a pair of JBL4315 from eBay, the speakers arrived yesterday, however, one of the woofer 2203A has a problem with no sound.

I took it out and swapped with the another 4315 woofer, which has no problem, meaning the crossover of the speakers are normal.

I used a multi meter to test the impedance of the woofer, and the reading is normal, however, when I use a 9w battery, it has a static sound but the cone does not pop in/out as the another one.

Now my questions :
1. Can this woofer be repaired e.g. by reconing ? As people said it can, but how about it is not the wire of the cone blow up?
2. Is there any replacement of this 2203A (some said 2202H can fit), I do not mind to replace both woofers at the same time, even sound quality is not as good as the original

Thank you

Hi,
is the foam of the other (working) 2203a still OK?
If not, maybe go for a swap to a little bit more modern pair of drivers like Beyma 12B100R. Many other brands are possible, even current production. The more recent, the more "different" the sound might be, though. Sounds strange, but newer materials have a different sound to them. Paper or alu coil formers are rare these days, Nomex might be your best bet. Choose copper wire, not alu, if given the choice.

If a JBL is what should go inside, either eBay hunting for a used 2203a/124a, or a orig. 2203 recone kit, or a pair of 2203H or maybe also a pair of 2204H units might be the way to go.

JBL 2202's will not work, those are short excursion units with stiff suspensions for stage wedge or studio monitor midrange application. 2202's will result in close to zero bass from those 4315 cabs despite their size. 2206's are better than 2202's but still far off from sounding similar

Ralph

[Flodstroem]

I used a multi meter to test the impedance of the woofer, and the reading is normal, however, when I use a 9w battery, it has a static sound but the cone does not pop in/out as the another one. Thank you

Hello snoopy

Try this: check for loose screws on the speaker terminals (inside of the basket). I have found many of those old speakers, especially those with Alnico motors (these are oldest) had loosened screws and unstable measures as a result . They can make sound but no power (dead) If you are lucky then you only had to screw the screws back again Its a little bit tricky because you had to work inside the basket where the cone is but it can be done with short screw-bits.

Check more for more details in this thread:
http://www.audioheritage.org/vbullet...ose-on-old-JBL

If that isnt the problem then it could be the speakers terminal wires/leads that could have an open circuit (when cone is moving) Try to ohm-measure right on the wires where they are connected to the cone. If broken it could be only some fibers left on those leads and the metal tinsel has ben broken or has ben corroded.

Btw, Welcome to the LHForum snoopy

[snoopy751]

Thank you for all the replies, appreciate

Ok thats what has happened, I bought this pair of 4315 from eBay, and got delivered few days ago.

After a listen I realised there was no bass from a speaker, so I took it out and have a test with multi meter, and the impedance reading was normal.

Finally, I brought to a shop in Sydney, called Speaker Hospital, and the guy was well experience and told me that, the 2203A was actually fine, however, might be due to the transportation, the paper cone got stuck and could not pop up, and he reckon the previous owner's reconing and reforming were done poorly, which caused the problem.

Therefore, they will recone both 2203A and replace the surround spider, disassemble and clean. Hope it works.

[gibber]

Thank you for all the replies, appreciate

Ok thats what has happened, I bought this pair of 4315 from eBay, and got delivered few days ago.

After a listen I realised there was no bass from a speaker, so I took it out and have a test with multi meter, and the impedance reading was normal.

Finally, I brought to a shop in Sydney, called Speaker Hospital, and the guy was well experience and told me that, the 2203A was actually fine, however, might be due to the transportation, the paper cone got stuck and could not pop up, and he reckon the previous owner's reconing and reforming were done poorly, which caused the problem.

Therefore, they will recone both 2203A and replace the surround spider, disassemble and clean. Hope it works.

Fine units no longer original unless that shop has the exact kits. Btw, re-reading the thread, i realize *the* likely cause is the pole has shifted sideways due to a strong bump during transport.

Would need de-mag, re-alignment, re-mag in this order and no new kit at all if the old one is salvaged carefully and put in again. Only new foams & dust cap, preferably on both.

[kelossus]

Thank you for all the replies, appreciate

Ok thats what has happened, I bought this pair of 4315 from eBay, and got delivered few days ago.

After a listen I realised there was no bass from a speaker, so I took it out and have a test with multi meter, and the impedance reading was normal.

Finally, I brought to a shop in Sydney, called Speaker Hospital, and the guy was well experience and told me that, the 2203A was actually fine, however, might be due to the transportation, the paper cone got stuck and could not pop up, and he reckon the previous owner's reconing and reforming were done poorly, which caused the problem.

Therefore, they will recone both 2203A and replace the surround spider, disassemble and clean. Hope it works.

Mate, I would be very wary of Speaker Hospital. They couldn't care less about old speakers, they are quite happen to stick the foam on the wrong side of the cone and build you a driver using aftermarket parts paying no attention to the original T/S specs of the driver.

I would be asking for T/S specs once they have rebuilt them.

In my experience there is no one is Sydney capable of rebuilding them properly.

Do you know where the 4315's came from? I have sold two pairs to people in Sydney, curious if they might be a set of mine.

[kelossus]

Btw, I have a set of genuine C8R2203A recones I would consider selling.

I would not let them go for nothing, they are extremely rare and cost me a fortune.

[bldozier]

Can you get some copies made

[snoopy751]

Mate, I would be very wary of Speaker Hospital. They couldn't care less about old speakers, they are quite happen to stick the foam on the wrong side of the cone and build you a driver using aftermarket parts paying no attention to the original T/S specs of the driver.

I would be asking for T/S specs once they have rebuilt them.

In my experience there is no one is Sydney capable of rebuilding them properly.

Do you know where the 4315's came from? I have sold two pairs to people in Sydney, curious if they might be a set of mine.

Understood. No I got it from USA however I am no sure whether the drivers had been reconed, reformed or serviced

[mech986]

Thank you for all the replies, appreciate

Ok thats what has happened, I bought this pair of 4315 from eBay, and got delivered few days ago.

After a listen I realised there was no bass from a speaker, so I took it out and have a test with multi meter, and the impedance reading was normal.

Finally, I brought to a shop in Sydney, called Speaker Hospital, and the guy was well experience and told me that, the 2203A was actually fine, however, might be due to the transportation, the paper cone got stuck and could not pop up, and he reckon the previous owner's reconing and reforming were done poorly, which caused the problem.

Therefore, they will recone both 2203A and replace the surround spider, disassemble and clean. Hope it works.

Fine units no longer original unless that shop has the exact kits. Btw, re-reading the thread, i realize *the* likely cause is the pole has shifted sideways due to a strong bump during transport.

Would need de-mag, re-alignment, re-mag in this order and no new kit at all if the old one is salvaged carefully and put in again. Only new foams & dust cap, preferably on both.

I would agree, the magnet probably shifted which is a much more difficult issue to address, not impossible, but requires skill. If there still is a good ohms reading on the voice coil, then have them VERY VERY carefully separate the surround and spider from the frame and, if possible, lift out the cone/voice coil assembly AND SAVE IT! It is half of the value of the driver. The voice coil should then be inspected for roundness and concentricity, plus the wire should be checked for any signs of burning, scraping, bubbling of insulation, or other damage - that will determine if it can be reused.

Then have the gap inspected and checked with a gap gauge to see if it is free of debris and is even all the way around the pole piece. If it isn't completely symmetrical, then the de-mag, alignment, and remag will need to be done to get the gap correct, of course, getting the magnet free and then regluing / bolting in place as needed.

I would check very carefully about the caveat above of the ability and skill of this shop if there already have been concerns - you want to keep the old parts, and they should not have any damage to them in the process of being removed, it isn't that difficult to preserve the parts. If they can't guarantee it, then you shouldn't be working with them and seek out someone else, even if on another continent.

[mech986]

mate, i would be very wary of speaker hospital. They couldn't care less about old speakers, they are quite happen to stick the foam on the wrong side of the cone and build you a driver using aftermarket parts paying no attention to the original t/s specs of the driver.

I would be asking for t/s specs once they have rebuilt them.

In my experience there is no one is sydney capable of rebuilding them properly.

Do you know where the 4315's came from? I have sold two pairs to people in sydney, curious if they might be a set of mine.

this^^^

[mech986]

By the way, what US state were these shipped from?

[gasfan]

Thank you for all the replies, appreciate

Ok thats what has happened, I bought this pair of 4315 from eBay, and got delivered few days ago.

After a listen I realised there was no bass from a speaker, so I took it out and have a test with multi meter, and the impedance reading was normal.

Finally, I brought to a shop in Sydney, called Speaker Hospital, and the guy was well experience and told me that, the 2203A was actually fine, however, might be due to the transportation, the paper cone got stuck and could not pop up, and he reckon the previous owner's reconing and reforming were done poorly, which caused the problem.

Therefore, they will recone both 2203A and replace the surround spider, disassemble and clean. Hope it works.

Have you checked to see if you can pull the cone forward? If you can, without scraping noises, there's a good chance that the foam dust screen on the pole piece broke up and got sucked into the vc gap and has turned to goo, causing the vc to stick in place. If this is the case, it just needs to be disassembled and cleaned. But don't put a new foam dust cap on. I would stop any reconing procedure by the shop if possible til this has been checked first. Otherwise, they'll likely just rip the original out of the basket and maybe destroy a perfectly good, extremely rare and expensive original cone.