LE120H in JBL Jubal?

[JesperSteen]

Hi dear forummembers

One of the 126a-woofers in my Jubals has died. Absolutely no sound.


Its difficult to get another 126a here in Denmark, and its quite expensive to buy and ship heavy speakers all the way abroad. But there is some LE120H for sale at decent prices. Is it an idea to get two of those - and could it maybe even improve the sound??

does any of you have any experiencies with LE120H - and maybe even in Jubals? Is there in fact enough space in the cabinet for a LE120H? The magnet seems to be a bit bigger than the old 126a's.

I hope somebody could help.

[Aaron]

A truly different woofer stands very little chance of playing nice with the crossover.
For that reason, would try to stick with woofers that use the same style of frame like the 128H or even the 123A to 2213H.
Barring that, the 2214H would probably at least fit in the hole.

Also, the stereo image will likely suffer if you don't have the same speakers on each side.

[speakerdave]

Tell us more about how this happened. I can't see a woofer just dying for no apparent reason. That would more likely be a failed connection or crossover component, I would think. Have you followed a systematic trouble shooting procedure to isolate the problem to the woofer?

[4343]

A truly different woofer stands very little chance of playing nice with the crossover.
For that reason, would try to stick with woofers that use the same style of frame like the 128H or even the 123A to 2213H.
Barring that, the 2214H would probably at least fit in the hole. ...

I think the 2214H measures 6mm more than those others you mention, not sure about the back side surface, but I had problems fitting a 2214H in the place of a 128H due to that extra 1/4" in a rear mount cabinet.

[BMWCCA]

The LE120H is from the L7's and is a very capable driver.

Is there a difference between the LE120H and the LE120H-1?

The LE120H crosses at 400HZ in the L90.
The LE120H1 crosses at 180HZ in the L7.
The L65/A crosses its variety of woofers at 1000HZ

[JesperSteen]

Tell us more about how this happened. I can't see a woofer just dying for no apparent reason. That would more likely be a failed connection or crossover component, I would think. Have you followed a systematic trouble shooting procedure to isolate the problem to the woofer?

Thank you all for the quick and kind replies!!

I have really no idea about the 'death-cause'. They've both worked well Since a reconing a few years ago, but suddenly the other day one of the woofers sounded like shit, like the voicecoil was scraping for a few minutes at moderate sound level, and then it just went silence. I've Since then tried to switch the two woofers and that test showed that it definetly is the one woofer that has gone.
maybe a new reconing is the best Solution? (As menthioned it has been done - by a pro - one time earlier, and maybe its a bad reconingjob then that has caused the new problem ?)

Before the Jubals I had 4311 for a long time - and in my opinion the bass was sounding 'tighter' in my old monitors than in the Jubals. So I'm ready to switch both woofers of course to a new woofersetup - if it helps. I'm well aware that I have to use same type on both sides - and that it maybe is a bit hazardous to put another type of woofer in my Jubals. But there is NO 126a's awailable here in Denmark at the moment - and it is quite expensive to fly 'solid old JBL-metal' over the ocean. On the other hand: killing my beloved Jubals is also NO option ;-)

cheers from Denmark

[hjames]

The wonder would be what could have killed a perfectly good woofer ..
Could the amp have a problem with putting DC on the output for that channel?
If it had been doing something like for a while, the voicecoil could be running hot, melt the varnish or make it bubble, and eventually "stick" in the gap.

Or maybe outputting a lot of energy into very low frequency/subsonics - which could also overheat the voicecoil.

Could be other causes, but I'd be careful and at least have the amp checked out.

Like other folks have said - its very unusual for a woofer to just die like that (they are usually pretty beefy).

Thank you all for the quick and kind replies!!

I have really no idea about the 'death-cause'. They've both worked well Since a reconing a few years ago, but suddenly the other day one of the woofers sounded like shit, like the voicecoil was scraping for a few minutes at moderate sound level, and then it just went silence. I've Since then tried to switch the two woofers and that test showed that it definetly is the one woofer that has gone.
maybe a new reconing is the best Solution? (As menthioned it has been done - by a pro - one time earlier, and maybe its a bad reconingjob then that has caused the new problem ?)

Before the Jubals I had 4311 for a long time - and in my opinion the bass was sounding 'tighter' in my old monitors than in the Jubals. So I'm ready to switch both woofers of course to a new woofersetup - if it helps. I'm well aware that I have to use same type on both sides - and that it maybe is a bit hazardous to put another type of woofer in my Jubals. But there is NO 126a's awailable here in Denmark at the moment - and it is quite expensive to fly 'solid old JBL-metal' over the ocean. On the other hand: killing my beloved Jubals is also NO option ;-)

cheers from Denmark

[JesperSteen]

The wonder would be what could have killed a perfectly good woofer ..
Could the amp have a problem with putting DC on the output for that channel?
If it had been doing something like for a while, the voicecoil could be running hot, melt the varnish or make it bubble, and eventually "stick" in the gap.

Or maybe outputting a lot of energy into very low frequency/subsonics - which could also overheat the voicecoil.

Could be other causes, but I'd be careful and at least have the amp checked out.

Like other folks have said - its very unusual for a woofer to just die like that (they are usually pretty beefy).

Yes, maybe you're right about some lowfrequent noice from the Cyrus-amp - or maybe bad cableconnections.
It would be a good idea to find the problem before I fix the Jubals

[speakerdave]

I believe the 126a cone kit is NLA. I don't know how long that's been true, but I do wonder if the recone done a few years ago used JBL factory kits.

[Aaron]

The other posters have excellent advice.
One tiny thing I can ad to their train of thought is to visually inspect the dead woofer: Maybe something happened to the tinsel leads. Also those spring loaded connectors on the woofer frame are plenty old and may have corroded enough to cause this problem. If you don't have a can of Deoxit, now would be a good time to get some and use it on pretty much all of your old audio connections.

[speakerdave]

If you change the woofer you would very likely need to change the inductor in the LF part of the crossover, and since it would be guess work what the new value should be, you probably should try to avoid getting into it.

Check with your reconer and find out whether the recones were aftermarket ones. If they were and you liked the performance, then the best solution might be to have it (or them) redone.

[JesperSteen]

I believe the 126a cone kit is NLA. I don't know how long that's been true, but I do wonder if the recone done a few years ago used JBL factory kits.

Yeah, you maybe right, but the other woofer that still works, had the same reconing and sounds fine - at the moment...;-)

I've now asked two pro reconers in Denmark for a price. If thats to expensive (or impossible) I'll guess i will try to get two JBL 128H or H-1, because they are recommended as upgrade or replacement by JBL. I guess that plan is the safest compared to experiments with e.g. LE120 or other woofer-types.

How does that plan sound in expert-ears? :-)

[speakerdave]

They are logical steps to take, I think.

Yeah, you maybe right, but the other woofer that still works, had the same reconing and sounds fine - at the moment...;-)

I've now asked two pro reconers in Denmark for a price. If thats to expensive (or impossible) I'll guess i will try to get two JBL 128H or H-1, because they are recommended as upgrade or replacement by JBL. I guess that plan is the safest compared to experiments with e.g. LE120 or other woofer-types.

How does that plan sound in expert-ears? :-)

[Audiobeer]

This is a long shot but on the back of some JBLs there is a little foam cover and they fall apart over time and can fall into the voice coil causing it to lock up. It happened to me. The coner took it apart cleaned it and it still works years later.

[JesperSteen]

This is a long shot but on the back of some JBLs there is a little foam cover and they fall apart over time and can fall into the voice coil causing it to lock up. It happened to me. The coner took it apart cleaned it and it still works years later.

Hey, maybe it was a longshot, but never the less you were completely right. I'm impressed!!! The repair-shop found some 'dirt' in the voicecoil and fixed it easily - and quite inexpensive. So now every idea about experimenting with new woofers are put aside for good. The Jubals now works brillant again with the 126A's back in business. (And I used the 'vacation', while the woofer was away for repair, to switch all the L-pads to new ones. I can really recommend that if the old ones 'schratch'. Its so easy and worked much better for me than cleaning-spray)
thanks to everybody for input in this thread.

Stay cool - play loud